feat(python): expose OAuth connection config

## Summary

Add the Rust OAuth header provider for remote LanceDB connections.

This supports client credentials and Azure managed identity flows,
handles token caching and refresh, redacts secrets in Debug output, and
wires `ConnectBuilder::oauth_config()` into the remote client while
rejecting ambiguous API-key/header-provider combinations.

.bumpversion.toml

@@ -1,5 +1,5 @@
 [tool.bumpversion]
-current_version = "0.31.0-beta.1"
+current_version = "0.31.0-beta.3"
 parse = """(?x)
     (?P<major>0|[1-9]\\d*)\\.
     (?P<minor>0|[1-9]\\d*)\\.

Cargo.lock

@@ -3432,8 +3432,8 @@ checksum = "42703706b716c37f96a77aea830392ad231f44c9e9a67872fa5548707e11b11c"
 
 [[package]]
 name = "fsst"
-version = "9.0.0-beta.2"
+version = "9.0.0-beta.8"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "arrow-array",
  "rand 0.9.4",
@@ -4735,8 +4735,8 @@ checksum = "e037a2e1d8d5fdbd49b16a4ea09d5d6401c1f29eca5ff29d03d3824dba16256a"
 
 [[package]]
 name = "lance"
-version = "9.0.0-beta.2"
+version = "9.0.0-beta.8"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "arc-swap",
  "arrow",
@@ -4771,7 +4771,7 @@ dependencies = [
  "futures",
  "half",
  "humantime",
- "itertools 0.13.0",
+ "itertools 0.14.0",
  "lance-arrow",
  "lance-core",
  "lance-datafusion",
@@ -4810,8 +4810,8 @@ dependencies = [
 
 [[package]]
 name = "lance-arrow"
-version = "9.0.0-beta.2"
+version = "9.0.0-beta.8"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "arrow-array",
  "arrow-buffer",
@@ -4832,7 +4832,7 @@ dependencies = [
 [[package]]
 name = "lance-arrow-scalar"
 version = "58.0.0"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "arrow-array",
  "arrow-buffer",
@@ -4846,7 +4846,7 @@ dependencies = [
 [[package]]
 name = "lance-arrow-stats"
 version = "58.0.0"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "arrow-array",
  "arrow-schema",
@@ -4855,8 +4855,8 @@ dependencies = [
 
 [[package]]
 name = "lance-bitpacking"
-version = "9.0.0-beta.2"
+version = "9.0.0-beta.8"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "arrayref",
  "paste",
@@ -4865,8 +4865,8 @@ dependencies = [
 
 [[package]]
 name = "lance-core"
-version = "9.0.0-beta.2"
+version = "9.0.0-beta.8"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "arrow-array",
  "arrow-buffer",
@@ -4878,7 +4878,7 @@ dependencies = [
  "datafusion-common",
  "datafusion-sql",
  "futures",
- "itertools 0.13.0",
+ "itertools 0.14.0",
  "lance-arrow",
  "lance-derive",
  "libc",
@@ -4904,8 +4904,8 @@ dependencies = [
 
 [[package]]
 name = "lance-datafusion"
-version = "9.0.0-beta.2"
+version = "9.0.0-beta.8"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "arrow",
  "arrow-array",
@@ -4935,8 +4935,8 @@ dependencies = [
 
 [[package]]
 name = "lance-datagen"
-version = "9.0.0-beta.2"
+version = "9.0.0-beta.8"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "arrow",
  "arrow-array",
@@ -4953,8 +4953,8 @@ dependencies = [
 
 [[package]]
 name = "lance-derive"
-version = "9.0.0-beta.2"
+version = "9.0.0-beta.8"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -4963,8 +4963,8 @@ dependencies = [
 
 [[package]]
 name = "lance-encoding"
-version = "9.0.0-beta.2"
+version = "9.0.0-beta.8"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "arrow-arith",
  "arrow-array",
@@ -4980,7 +4980,7 @@ dependencies = [
  "futures",
  "hex",
  "hyperloglogplus",
- "itertools 0.13.0",
+ "itertools 0.14.0",
  "lance-arrow",
  "lance-bitpacking",
  "lance-core",
@@ -4999,8 +4999,8 @@ dependencies = [
 
 [[package]]
 name = "lance-file"
-version = "9.0.0-beta.2"
+version = "9.0.0-beta.8"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "arrow-arith",
  "arrow-array",
@@ -5030,8 +5030,8 @@ dependencies = [
 
 [[package]]
 name = "lance-index"
-version = "9.0.0-beta.2"
+version = "9.0.0-beta.8"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "arc-swap",
  "arrow",
@@ -5056,7 +5056,7 @@ dependencies = [
  "fst",
  "futures",
  "half",
- "itertools 0.13.0",
+ "itertools 0.14.0",
  "jieba-rs",
  "jsonb",
  "lance-arrow",
@@ -5096,8 +5096,8 @@ dependencies = [
 
 [[package]]
 name = "lance-io"
-version = "9.0.0-beta.2"
+version = "9.0.0-beta.8"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "arrow",
  "arrow-arith",
@@ -5138,8 +5138,8 @@ dependencies = [
 
 [[package]]
 name = "lance-linalg"
-version = "9.0.0-beta.2"
+version = "9.0.0-beta.8"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "arrow-array",
  "arrow-buffer",
@@ -5155,8 +5155,8 @@ dependencies = [
 
 [[package]]
 name = "lance-namespace"
-version = "9.0.0-beta.2"
+version = "9.0.0-beta.8"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "arrow",
  "async-trait",
@@ -5168,8 +5168,8 @@ dependencies = [
 
 [[package]]
 name = "lance-namespace-impls"
-version = "9.0.0-beta.2"
+version = "9.0.0-beta.8"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "arrow",
  "arrow-ipc",
@@ -5223,15 +5223,15 @@ dependencies = [
 
 [[package]]
 name = "lance-select"
-version = "9.0.0-beta.2"
+version = "9.0.0-beta.8"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "arrow-array",
  "arrow-buffer",
  "arrow-schema",
  "byteorder",
  "bytes",
- "itertools 0.13.0",
+ "itertools 0.14.0",
  "lance-core",
  "roaring",
  "tracing",
@@ -5239,8 +5239,8 @@ dependencies = [
 
 [[package]]
 name = "lance-table"
-version = "9.0.0-beta.2"
+version = "9.0.0-beta.8"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "arrow",
  "arrow-array",
@@ -5279,8 +5279,8 @@ dependencies = [
 
 [[package]]
 name = "lance-testing"
-version = "9.0.0-beta.2"
+version = "9.0.0-beta.8"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "arrow-array",
  "arrow-schema",
@@ -5293,8 +5293,8 @@ dependencies = [
 
 [[package]]
 name = "lance-tokenizer"
-version = "9.0.0-beta.2"
+version = "9.0.0-beta.8"
-source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.2#23211989de648fefc4454f5eee09ec176f0a465b"
+source = "git+https://github.com/lance-format/lance.git?tag=v9.0.0-beta.8#71c4aa2174971e98acb7e256fde1e1589024f5bc"
 dependencies = [
  "icu_segmenter",
  "jieba-rs",
@@ -5307,7 +5307,7 @@ dependencies = [
 
 [[package]]
 name = "lancedb"
-version = "0.31.0-beta.1"
+version = "0.31.0-beta.3"
 dependencies = [
  "ahash",
  "anyhow",
@@ -5384,13 +5384,14 @@ dependencies = [
  "tokenizers",
  "tokio",
  "url",
+ "urlencoding",
  "uuid",
  "walkdir",
 ]
 
 [[package]]
 name = "lancedb-nodejs"
-version = "0.31.0-beta.1"
+version = "0.31.0-beta.3"
 dependencies = [
  "arrow-array",
  "arrow-buffer",
@@ -5415,7 +5416,7 @@ dependencies = [
 
 [[package]]
 name = "lancedb-python"
-version = "0.34.0-beta.1"
+version = "0.34.0-beta.3"
 dependencies = [
  "arrow",
  "async-trait",

Cargo.toml

@@ -13,20 +13,20 @@ categories = ["database-implementations"]
 rust-version = "1.91.0"
 
 [workspace.dependencies]
-lance = { "version" = "=9.0.0-beta.2", default-features = false, "tag" = "v9.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance = { "version" = "=9.0.0-beta.8", default-features = false, "tag" = "v9.0.0-beta.8", "git" = "https://github.com/lance-format/lance.git" }
-lance-core = { "version" = "=9.0.0-beta.2", "tag" = "v9.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-core = { "version" = "=9.0.0-beta.8", "tag" = "v9.0.0-beta.8", "git" = "https://github.com/lance-format/lance.git" }
-lance-datagen = { "version" = "=9.0.0-beta.2", "tag" = "v9.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-datagen = { "version" = "=9.0.0-beta.8", "tag" = "v9.0.0-beta.8", "git" = "https://github.com/lance-format/lance.git" }
-lance-file = { "version" = "=9.0.0-beta.2", "tag" = "v9.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-file = { "version" = "=9.0.0-beta.8", "tag" = "v9.0.0-beta.8", "git" = "https://github.com/lance-format/lance.git" }
-lance-io = { "version" = "=9.0.0-beta.2", default-features = false, "tag" = "v9.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-io = { "version" = "=9.0.0-beta.8", default-features = false, "tag" = "v9.0.0-beta.8", "git" = "https://github.com/lance-format/lance.git" }
-lance-index = { "version" = "=9.0.0-beta.2", "tag" = "v9.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-index = { "version" = "=9.0.0-beta.8", "tag" = "v9.0.0-beta.8", "git" = "https://github.com/lance-format/lance.git" }
-lance-linalg = { "version" = "=9.0.0-beta.2", "tag" = "v9.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-linalg = { "version" = "=9.0.0-beta.8", "tag" = "v9.0.0-beta.8", "git" = "https://github.com/lance-format/lance.git" }
-lance-namespace = { "version" = "=9.0.0-beta.2", "tag" = "v9.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-namespace = { "version" = "=9.0.0-beta.8", "tag" = "v9.0.0-beta.8", "git" = "https://github.com/lance-format/lance.git" }
-lance-namespace-impls = { "version" = "=9.0.0-beta.2", default-features = false, "tag" = "v9.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-namespace-impls = { "version" = "=9.0.0-beta.8", default-features = false, "tag" = "v9.0.0-beta.8", "git" = "https://github.com/lance-format/lance.git" }
-lance-table = { "version" = "=9.0.0-beta.2", "tag" = "v9.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-table = { "version" = "=9.0.0-beta.8", "tag" = "v9.0.0-beta.8", "git" = "https://github.com/lance-format/lance.git" }
-lance-testing = { "version" = "=9.0.0-beta.2", "tag" = "v9.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-testing = { "version" = "=9.0.0-beta.8", "tag" = "v9.0.0-beta.8", "git" = "https://github.com/lance-format/lance.git" }
-lance-datafusion = { "version" = "=9.0.0-beta.2", "tag" = "v9.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-datafusion = { "version" = "=9.0.0-beta.8", "tag" = "v9.0.0-beta.8", "git" = "https://github.com/lance-format/lance.git" }
-lance-encoding = { "version" = "=9.0.0-beta.2", "tag" = "v9.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-encoding = { "version" = "=9.0.0-beta.8", "tag" = "v9.0.0-beta.8", "git" = "https://github.com/lance-format/lance.git" }
-lance-arrow = { "version" = "=9.0.0-beta.2", "tag" = "v9.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-arrow = { "version" = "=9.0.0-beta.8", "tag" = "v9.0.0-beta.8", "git" = "https://github.com/lance-format/lance.git" }
 ahash = "0.8"
 # Note that this one does not include pyarrow
 arrow = { version = "58.0.0", optional = false }

docs/src/java/java.md

@@ -14,7 +14,7 @@ Add the following dependency to your `pom.xml`:
 <dependency>
     <groupId>com.lancedb</groupId>
     <artifactId>lancedb-core</artifactId>
-    <version>0.31.0-beta.1</version>
+    <version>0.31.0-beta.3</version>
 </dependency>
 ```
 

java/lancedb-core/pom.xml

@@ -8,7 +8,7 @@
     <parent>
       <groupId>com.lancedb</groupId>
       <artifactId>lancedb-parent</artifactId>
-      <version>0.31.0-beta.1</version>
+      <version>0.31.0-beta.3</version>
       <relativePath>../pom.xml</relativePath>
     </parent>
 

java/pom.xml

@@ -6,7 +6,7 @@
 
     <groupId>com.lancedb</groupId>
     <artifactId>lancedb-parent</artifactId>
-    <version>0.31.0-beta.1</version>
+    <version>0.31.0-beta.3</version>
     <packaging>pom</packaging>
     <name>${project.artifactId}</name>
     <description>LanceDB Java SDK Parent POM</description>
@@ -28,7 +28,7 @@
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <arrow.version>15.0.0</arrow.version>
-        <lance-core.version>9.0.0-beta.2</lance-core.version>
+        <lance-core.version>9.0.0-beta.8</lance-core.version>
         <spotless.skip>false</spotless.skip>
         <spotless.version>2.30.0</spotless.version>
         <spotless.java.googlejavaformat.version>1.7</spotless.java.googlejavaformat.version>

nodejs/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "lancedb-nodejs"
 edition.workspace = true
-version = "0.31.0-beta.1"
+version = "0.31.0-beta.3"
 publish = false
 license.workspace = true
 description.workspace = true

nodejs/npm/darwin-arm64/package.json

@@ -1,6 +1,6 @@
 {
 	"name": "@lancedb/lancedb-darwin-arm64",
-	"version": "0.31.0-beta.1",
+	"version": "0.31.0-beta.3",
 	"os": ["darwin"],
 	"cpu": ["arm64"],
 	"main": "lancedb.darwin-arm64.node",

nodejs/npm/linux-arm64-gnu/package.json

@@ -1,6 +1,6 @@
 {
 	"name": "@lancedb/lancedb-linux-arm64-gnu",
-	"version": "0.31.0-beta.1",
+	"version": "0.31.0-beta.3",
 	"os": ["linux"],
 	"cpu": ["arm64"],
 	"main": "lancedb.linux-arm64-gnu.node",

nodejs/npm/linux-arm64-musl/package.json

@@ -1,6 +1,6 @@
 {
 	"name": "@lancedb/lancedb-linux-arm64-musl",
-	"version": "0.31.0-beta.1",
+	"version": "0.31.0-beta.3",
 	"os": ["linux"],
 	"cpu": ["arm64"],
 	"main": "lancedb.linux-arm64-musl.node",

nodejs/npm/linux-x64-gnu/package.json

@@ -1,6 +1,6 @@
 {
 	"name": "@lancedb/lancedb-linux-x64-gnu",
-	"version": "0.31.0-beta.1",
+	"version": "0.31.0-beta.3",
 	"os": ["linux"],
 	"cpu": ["x64"],
 	"main": "lancedb.linux-x64-gnu.node",

nodejs/npm/linux-x64-musl/package.json

@@ -1,6 +1,6 @@
 {
 	"name": "@lancedb/lancedb-linux-x64-musl",
-	"version": "0.31.0-beta.1",
+	"version": "0.31.0-beta.3",
 	"os": ["linux"],
 	"cpu": ["x64"],
 	"main": "lancedb.linux-x64-musl.node",

nodejs/npm/win32-arm64-msvc/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@lancedb/lancedb-win32-arm64-msvc",
-  "version": "0.31.0-beta.1",
+  "version": "0.31.0-beta.3",
   "os": [
     "win32"
   ],

nodejs/npm/win32-x64-msvc/package.json

@@ -1,6 +1,6 @@
 {
 	"name": "@lancedb/lancedb-win32-x64-msvc",
-	"version": "0.31.0-beta.1",
+	"version": "0.31.0-beta.3",
 	"os": ["win32"],
 	"cpu": ["x64"],
 	"main": "lancedb.win32-x64-msvc.node",

nodejs/package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "@lancedb/lancedb",
-  "version": "0.31.0-beta.1",
+  "version": "0.31.0-beta.3",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "@lancedb/lancedb",
-      "version": "0.31.0-beta.1",
+      "version": "0.31.0-beta.3",
       "cpu": [
         "x64",
         "arm64"

nodejs/package.json

@@ -11,7 +11,7 @@
     "ann"
   ],
   "private": false,
-  "version": "0.31.0-beta.1",
+  "version": "0.31.0-beta.3",
   "main": "dist/index.js",
   "exports": {
     ".": "./dist/index.js",

python/.bumpversion.toml

@@ -1,5 +1,5 @@
 [tool.bumpversion]
-current_version = "0.34.0-beta.2"
+current_version = "0.34.0-beta.3"
 parse = """(?x)
     (?P<major>0|[1-9]\\d*)\\.
     (?P<minor>0|[1-9]\\d*)\\.

python/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "lancedb-python"
-version = "0.34.0-beta.2"
+version = "0.34.0-beta.3"
 publish = false
 edition.workspace = true
 description = "Python bindings for LanceDB"

python/python/lancedb/__init__.py

@@ -89,6 +89,8 @@ def connect(
         If presented, connect to LanceDB cloud.
         Otherwise, connect to a database on file system or cloud storage.
         Can be set via environment variable `LANCEDB_API_KEY`.
+        OAuth configuration is currently supported only by ``connect_async``;
+        synchronous LanceDB Cloud connections require an API key.
     region: str, default "us-east-1"
         The region to use for LanceDB Cloud.
     host_override: str, optional
@@ -340,6 +342,7 @@ async def connect_async(
     session: Optional[Session] = None,
     manifest_enabled: bool = False,
     namespace_client_properties: Optional[Dict[str, str]] = None,
+    oauth_config=None,
 ) -> AsyncConnection:
     """Connect to a LanceDB database.
 
@@ -389,6 +392,10 @@ async def connect_async(
     namespace_client_properties : dict, optional
         Additional directory namespace client properties to use with
         ``manifest_enabled=True``.
+    oauth_config : OAuthConfig, optional
+        OAuth configuration for LanceDB Cloud/Enterprise. This is supported by
+        ``connect_async`` only; synchronous ``connect`` uses API key
+        authentication for ``db://`` URIs.
 
     Examples
     --------
@@ -435,6 +442,7 @@ async def connect_async(
             session,
             manifest_enabled,
             namespace_client_properties,
+            oauth_config,
         )
     )
 

python/python/lancedb/_lancedb.pyi

@@ -280,6 +280,7 @@ async def connect(
     session: Optional[Session],
     manifest_enabled: bool = False,
     namespace_client_properties: Optional[Dict[str, str]] = None,
+    oauth_config: Optional[Any] = None,
 ) -> Connection: ...
 
 class RecordBatchStream:

python/python/lancedb/embeddings/colpali.py

@@ -81,6 +81,7 @@ class ColPaliEmbeddings(EmbeddingFunction):
             warnings.warn(
                 "use_token_pooling is deprecated, use pooling_strategy=None instead",
                 DeprecationWarning,
+                stacklevel=2,
             )
             self.pooling_strategy = None
 

python/python/lancedb/namespace.py

@@ -373,6 +373,19 @@ def _convert_pyarrow_schema_to_json(schema: pa.Schema) -> JsonArrowSchema:
     return JsonArrowSchema(fields=fields, metadata=meta)
 
 
+def _builds_namespace_natively(
+    namespace_client_impl: Optional[str],
+    namespace_client_properties: Optional[Dict[str, str]],
+) -> bool:
+    """Whether ``connect_namespace_client`` builds the namespace client natively
+    in Rust (installing the read-freshness context provider) rather than wrapping
+    the pre-built Python client.
+
+    Must mirror Rust ``build_namespace_natively`` in ``python/src/connection.rs``.
+    """
+    return namespace_client_impl == "rest" and bool(namespace_client_properties)
+
+
 class LanceNamespaceDBConnection(DBConnection):
     """
     A LanceDB connection that uses a namespace for table management.
@@ -432,6 +445,13 @@ class LanceNamespaceDBConnection(DBConnection):
         )
         self._namespace_client_impl = namespace_client_impl
         self._namespace_client_properties = namespace_client_properties
+        # When the namespace client is built natively (see Rust
+        # ``build_namespace_natively``), the underlying Rust table performs
+        # QueryTable pushdown through the read-freshness context provider, which
+        # the pure-Python ``query_table`` path bypasses.
+        self._route_pushdown_to_rust = _builds_namespace_natively(
+            namespace_client_impl, namespace_client_properties
+        )
         self._inner = AsyncConnection(
             _connect_namespace_client(
                 namespace_client,
@@ -543,6 +563,7 @@ class LanceNamespaceDBConnection(DBConnection):
             namespace_path=namespace_path,
             namespace_client=self._namespace_client,
             pushdown_operations=self._namespace_client_pushdown_operations,
+            route_pushdown_to_rust=self._route_pushdown_to_rust,
             _async=async_table,
         )
 
@@ -580,6 +601,7 @@ class LanceNamespaceDBConnection(DBConnection):
             namespace_path=namespace_path,
             namespace_client=self._namespace_client,
             pushdown_operations=self._namespace_client_pushdown_operations,
+            route_pushdown_to_rust=self._route_pushdown_to_rust,
             _async=async_table,
         )
         if branch is not None:
@@ -875,6 +897,8 @@ class AsyncLanceNamespaceDBConnection:
         storage_options: Optional[Dict[str, str]] = None,
         session: Optional[Session] = None,
         namespace_client_pushdown_operations: Optional[List[str]] = None,
+        namespace_client_impl: Optional[str] = None,
+        namespace_client_properties: Optional[Dict[str, str]] = None,
     ):
         """
         Initialize an async namespace-based LanceDB connection.
@@ -900,6 +924,12 @@ class AsyncLanceNamespaceDBConnection:
               namespace.create_table() instead of using declare_table + local write.
 
             Default is None (no pushdown, all operations run locally).
+        namespace_client_impl : Optional[str]
+            The namespace implementation name used to create this connection.
+            Required (with ``namespace_client_properties``) for the Rust client to
+            be built natively and install the read-freshness provider.
+        namespace_client_properties : Optional[Dict[str, str]]
+            The namespace properties used to create this connection.
         """
         self._namespace_client = namespace_client
         self.read_consistency_interval = read_consistency_interval
@@ -908,6 +938,14 @@ class AsyncLanceNamespaceDBConnection:
         self._namespace_client_pushdown_operations = set(
             namespace_client_pushdown_operations or []
         )
+        self._namespace_client_impl = namespace_client_impl
+        self._namespace_client_properties = namespace_client_properties
+        # See LanceNamespaceDBConnection: when built natively the Rust table runs
+        # QueryTable pushdown through the read-freshness provider, so defer to it
+        # rather than the urllib3 client (which omits x-lancedb-min-timestamp).
+        self._route_pushdown_to_rust = _builds_namespace_natively(
+            namespace_client_impl, namespace_client_properties
+        )
         self._inner = AsyncConnection(
             _connect_namespace_client(
                 namespace_client,
@@ -921,8 +959,8 @@ class AsyncLanceNamespaceDBConnection:
                 namespace_client_pushdown_operations=(
                     list(self._namespace_client_pushdown_operations)
                 ),
-                namespace_client_impl=None,
+                namespace_client_impl=namespace_client_impl,
-                namespace_client_properties=None,
+                namespace_client_properties=namespace_client_properties,
             )
         )
 
@@ -992,6 +1030,7 @@ class AsyncLanceNamespaceDBConnection:
             namespace_path=namespace_path,
             namespace_client=self._namespace_client,
             pushdown_operations=self._namespace_client_pushdown_operations,
+            route_pushdown_to_rust=self._route_pushdown_to_rust,
         )
 
     async def open_table(
@@ -1029,6 +1068,7 @@ class AsyncLanceNamespaceDBConnection:
             namespace_path=namespace_path,
             namespace_client=self._namespace_client,
             pushdown_operations=self._namespace_client_pushdown_operations,
+            route_pushdown_to_rust=self._route_pushdown_to_rust,
         )
 
     async def drop_table(self, name: str, namespace_path: Optional[List[str]] = None):
@@ -1387,4 +1427,6 @@ def connect_namespace_async(
         storage_options=storage_options,
         session=session,
         namespace_client_pushdown_operations=namespace_client_pushdown_operations,
+        namespace_client_impl=namespace_client_impl,
+        namespace_client_properties=namespace_client_properties,
     )

python/python/lancedb/remote/__init__.py

@@ -9,6 +9,7 @@ from typing import List, Optional
 from lancedb import __version__
 
 from .header import HeaderProvider
+from .oauth import OAuthConfig, OAuthFlowType
 
 __all__ = [
     "TimeoutConfig",
@@ -16,6 +17,8 @@ __all__ = [
     "TlsConfig",
     "ClientConfig",
     "HeaderProvider",
+    "OAuthConfig",
+    "OAuthFlowType",
 ]
 
 

python/python/lancedb/remote/db.py

@@ -124,6 +124,7 @@ class RemoteDBConnection(DBConnection):
                 "request_thread_pool is no longer used and will be removed in "
                 "a future release.",
                 DeprecationWarning,
+                stacklevel=2,
             )
 
         if connection_timeout is not None:
@@ -132,6 +133,7 @@ class RemoteDBConnection(DBConnection):
                 "release. Please use client_config.timeout_config.connect_timeout "
                 "instead.",
                 DeprecationWarning,
+                stacklevel=2,
             )
             client_config.timeout_config.connect_timeout = timedelta(
                 seconds=connection_timeout
@@ -142,6 +144,7 @@ class RemoteDBConnection(DBConnection):
                 "read_timeout is deprecated and will be removed in a future release. "
                 "Please use client_config.timeout_config.read_timeout instead.",
                 DeprecationWarning,
+                stacklevel=2,
             )
             client_config.timeout_config.read_timeout = timedelta(seconds=read_timeout)
 

python/python/lancedb/remote/oauth.py

@@ -0,0 +1,75 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright The LanceDB Authors
+
+from dataclasses import dataclass, field
+from enum import Enum
+from typing import List, Optional
+
+
+class OAuthFlowType(str, Enum):
+    """OAuth authentication flow types."""
+
+    CLIENT_CREDENTIALS = "client_credentials"
+    """Client Credentials grant (service-to-service / M2M)."""
+
+    AZURE_MANAGED_IDENTITY = "azure_managed_identity"
+    """Azure Managed Identity via IMDS."""
+
+
+@dataclass
+class OAuthConfig:
+    """OAuth configuration for LanceDB authentication.
+
+    All token acquisition and refresh is handled in the Rust layer.
+    This config is passed through to Rust via PyO3.
+
+    Parameters
+    ----------
+    issuer_url : str
+        OIDC issuer URL or OAuth authority URL.
+        For Azure: ``https://login.microsoftonline.com/{tenant_id}/v2.0``
+    client_id : str
+        Application / Client ID.
+    scopes : List[str]
+        OAuth scopes to request.
+        For Azure managed identity, exactly one scope or resource is required.
+        For example: ``["api://{app_id}/.default"]``
+    flow : OAuthFlowType
+        Authentication flow to use. Default: CLIENT_CREDENTIALS.
+    client_secret : Optional[str]
+        Client secret (required for CLIENT_CREDENTIALS).
+    managed_identity_client_id : Optional[str]
+        Client ID for user-assigned managed identity (AZURE_MANAGED_IDENTITY).
+    refresh_buffer_secs : Optional[int]
+        Seconds before expiry to trigger proactive refresh (default: 300).
+        Keep this well below the token TTL; if it is greater than or equal to
+        the TTL, each request refreshes the token.
+
+    Examples
+    --------
+    Client Credentials (service-to-service):
+
+    >>> config = OAuthConfig(
+    ...     issuer_url="https://login.microsoftonline.com/{tenant}/v2.0",
+    ...     client_id="app-id",
+    ...     client_secret="secret",
+    ...     scopes=["api://lancedb-api/.default"],
+    ... )
+
+    Azure Managed Identity:
+
+    >>> config = OAuthConfig(
+    ...     issuer_url="https://login.microsoftonline.com/{tenant}/v2.0",
+    ...     client_id="app-id",
+    ...     scopes=["api://lancedb-api/.default"],
+    ...     flow=OAuthFlowType.AZURE_MANAGED_IDENTITY,
+    ... )
+    """
+
+    issuer_url: str
+    client_id: str
+    scopes: List[str]
+    flow: OAuthFlowType = OAuthFlowType.CLIENT_CREDENTIALS
+    client_secret: Optional[str] = field(default=None, repr=False)
+    managed_identity_client_id: Optional[str] = None
+    refresh_buffer_secs: Optional[int] = None

python/python/lancedb/remote/table.py

@@ -845,7 +845,8 @@ class RemoteTable(Table):
         """
         warnings.warn(
             "cleanup_old_versions() is a no-op on LanceDB Cloud. "
-            "Tables are automatically cleaned up and optimized."
+            "Tables are automatically cleaned up and optimized.",
+            stacklevel=2,
         )
         pass
 
@@ -857,7 +858,8 @@ class RemoteTable(Table):
         """
         warnings.warn(
             "compact_files() is a no-op on LanceDB Cloud. "
-            "Tables are automatically compacted and optimized."
+            "Tables are automatically compacted and optimized.",
+            stacklevel=2,
         )
         pass
 
@@ -874,7 +876,8 @@ class RemoteTable(Table):
         """
         warnings.warn(
             "optimize() is a no-op on LanceDB Cloud. "
-            "Indices are optimized automatically."
+            "Indices are optimized automatically.",
+            stacklevel=2,
         )
         pass
 

python/python/lancedb/table.py

@@ -2022,6 +2022,7 @@ class LanceTable(Table):
         namespace_client: Optional[Any] = None,
         managed_versioning: Optional[bool] = None,
         pushdown_operations: Optional[set] = None,
+        route_pushdown_to_rust: bool = False,
         _async: AsyncTable = None,
     ):
         if namespace_path is None:
@@ -2031,6 +2032,14 @@ class LanceTable(Table):
         self._location = location  # Store location for use in _dataset_path
         self._namespace_client = namespace_client
         self._pushdown_operations = pushdown_operations or set()
+        # When the connection built the namespace client natively (e.g. an
+        # enterprise "rest" connection), the underlying Rust table already
+        # executes QueryTable pushdown itself -- and, unlike this Python urllib3
+        # path, it routes through the read-freshness context provider that emits
+        # the ``x-lancedb-min-timestamp`` header. So we must defer pushdown to
+        # Rust instead of calling the Python ``namespace_client.query_table``
+        # directly, or reads silently bypass read-freshness (stale results).
+        self._route_pushdown_to_rust = route_pushdown_to_rust
         if _async is not None:
             self._table = _async
         else:
@@ -2241,6 +2250,7 @@ class LanceTable(Table):
             namespace_path=self._namespace_path,
             namespace_client=self._namespace_client,
             pushdown_operations=self._pushdown_operations,
+            route_pushdown_to_rust=self._route_pushdown_to_rust,
             location=self._location,
             _async=async_table,
         )
@@ -2391,8 +2401,11 @@ class LanceTable(Table):
         Returns
         -------
         pa.Table"""
-        if _should_push_down_query_table(
+        if (
-            self._namespace_client, self._pushdown_operations
+            _should_push_down_query_table(
+                self._namespace_client, self._pushdown_operations
+            )
+            and not self._route_pushdown_to_rust
         ):
             return self._execute_query(Query()).read_all()
 
@@ -3344,6 +3357,7 @@ class LanceTable(Table):
         location: Optional[str] = None,
         namespace_client: Optional[Any] = None,
         pushdown_operations: Optional[set] = None,
+        route_pushdown_to_rust: bool = False,
     ):
         """
         Create a new table.
@@ -3406,21 +3420,24 @@ class LanceTable(Table):
         self._location = location
         self._namespace_client = namespace_client
         self._pushdown_operations = pushdown_operations or set()
+        self._route_pushdown_to_rust = route_pushdown_to_rust
 
         if data_storage_version is not None:
             warnings.warn(
-                "setting data_storage_version directly on create_table is deprecated. ",
+                "setting data_storage_version directly on create_table is deprecated. "
                 "Use database_options instead.",
                 DeprecationWarning,
+                stacklevel=2,
             )
             if storage_options is None:
                 storage_options = {}
             storage_options["new_table_data_storage_version"] = data_storage_version
         if enable_v2_manifest_paths is not None:
             warnings.warn(
-                "setting enable_v2_manifest_paths directly on create_table is ",
+                "setting enable_v2_manifest_paths directly on create_table is "
                 "deprecated. Use database_options instead.",
                 DeprecationWarning,
+                stacklevel=2,
             )
             if storage_options is None:
                 storage_options = {}
@@ -3517,6 +3534,7 @@ class LanceTable(Table):
             _should_push_down_query_table(
                 self._namespace_client, self._pushdown_operations
             )
+            and not self._route_pushdown_to_rust
             and self.current_branch() is None
         ):
             from lancedb.namespace import _execute_server_side_query
@@ -4258,6 +4276,7 @@ class AsyncTable:
         namespace_path: Optional[List[str]] = None,
         namespace_client: Optional[Any] = None,
         pushdown_operations: Optional[set] = None,
+        route_pushdown_to_rust: bool = False,
     ):
         """Create a new AsyncTable object.
 
@@ -4270,6 +4289,9 @@ class AsyncTable:
         self._namespace_path = namespace_path or []
         self._namespace_client = namespace_client
         self._pushdown_operations = pushdown_operations or set()
+        # See LanceTable.__init__: defer QueryTable pushdown to Rust (which emits
+        # the read-freshness header) for natively-built namespace clients.
+        self._route_pushdown_to_rust = route_pushdown_to_rust
 
     def _set_namespace_context(
         self,
@@ -4277,10 +4299,12 @@ class AsyncTable:
         namespace_path: Optional[List[str]] = None,
         namespace_client: Optional[Any] = None,
         pushdown_operations: Optional[set] = None,
+        route_pushdown_to_rust: bool = False,
     ) -> "AsyncTable":
         self._namespace_path = namespace_path or []
         self._namespace_client = namespace_client
         self._pushdown_operations = pushdown_operations or set()
+        self._route_pushdown_to_rust = route_pushdown_to_rust
         return self
 
     def __repr__(self):
@@ -4490,8 +4514,11 @@ class AsyncTable:
         -------
         pa.Table
         """
-        if _should_push_down_query_table(
+        if (
-            self._namespace_client, self._pushdown_operations
+            _should_push_down_query_table(
+                self._namespace_client, self._pushdown_operations
+            )
+            and not self._route_pushdown_to_rust
         ):
             return (await self._execute_query(Query())).read_all()
 
@@ -5175,8 +5202,11 @@ class AsyncTable:
         batch_size: Optional[int] = None,
         timeout: Optional[timedelta] = None,
     ) -> pa.RecordBatchReader:
-        if _should_push_down_query_table(
+        if (
-            self._namespace_client, self._pushdown_operations
+            _should_push_down_query_table(
+                self._namespace_client, self._pushdown_operations
+            )
+            and not self._route_pushdown_to_rust
         ):
             from lancedb.namespace import _execute_server_side_query
 
@@ -5662,6 +5692,7 @@ class AsyncTable:
                 "The 'retrain' parameter is deprecated and will be removed in a "
                 "future version.",
                 DeprecationWarning,
+                stacklevel=2,
             )
 
         return await self._inner.optimize(

python/python/tests/test_namespace.py

@@ -65,6 +65,9 @@ def _namespace_lance_table(namespace_client: _NamespaceClient) -> LanceTable:
     table._namespace_path = ["geneva"]
     table._namespace_client = namespace_client
     table._pushdown_operations = {"QueryTable"}
+    # This test exercises the Python-side pushdown path (non-native client), so
+    # pushdown is not routed to Rust.
+    table._route_pushdown_to_rust = False
     return table
 
 
@@ -805,6 +808,37 @@ class TestPushdownOperations:
         db = lancedb.connect_namespace("dir", {"root": self.temp_dir})
         assert len(db._namespace_client_pushdown_operations) == 0
 
+    def test_route_pushdown_to_rust_for_native_rest(self):
+        """A natively-built rest connection must defer QueryTable pushdown to
+        Rust so reads carry the x-lancedb-min-timestamp read-freshness header."""
+        db = lancedb.connect_namespace(
+            "rest",
+            {"uri": "http://localhost:12345"},
+            namespace_client_pushdown_operations=["QueryTable"],
+        )
+        assert db._route_pushdown_to_rust is True
+
+    def test_route_pushdown_to_rust_false_for_dir(self):
+        """A non-native (dir) connection keeps the Python pushdown path."""
+        db = lancedb.connect_namespace("dir", {"root": self.temp_dir})
+        assert db._route_pushdown_to_rust is False
+
+    def test_async_route_pushdown_to_rust_for_native_rest(self):
+        """The async connection must not silently bypass the read-freshness fix:
+        a natively-built rest connection defers pushdown to Rust (regression test
+        for the async path omitting the freshness header)."""
+        db = lancedb.connect_namespace_async(
+            "rest",
+            {"uri": "http://localhost:12345"},
+            namespace_client_pushdown_operations=["QueryTable"],
+        )
+        assert db._route_pushdown_to_rust is True
+
+    def test_async_route_pushdown_to_rust_false_for_dir(self):
+        """The async non-native (dir) connection keeps the Python pushdown path."""
+        db = lancedb.connect_namespace_async("dir", {"root": self.temp_dir})
+        assert db._route_pushdown_to_rust is False
+
     def test_lance_table_to_arrow_uses_query_pushdown(self):
         namespace_client = _NamespaceClient()
         table = _namespace_lance_table(namespace_client)

python/src/connection.rs

@@ -539,7 +539,7 @@ impl Connection {
 }
 
 #[pyfunction]
-#[pyo3(signature = (uri, api_key=None, region=None, host_override=None, read_consistency_interval=None, client_config=None, storage_options=None, session=None, manifest_enabled=false, namespace_client_properties=None))]
+#[pyo3(signature = (uri, api_key=None, region=None, host_override=None, read_consistency_interval=None, client_config=None, storage_options=None, session=None, manifest_enabled=false, namespace_client_properties=None, oauth_config=None))]
 #[allow(clippy::too_many_arguments)]
 pub fn connect(
     py: Python<'_>,
@@ -553,6 +553,7 @@ pub fn connect(
     session: Option<crate::session::Session>,
     manifest_enabled: bool,
     namespace_client_properties: Option<HashMap<String, String>>,
+    oauth_config: Option<crate::oauth::PyOAuthConfig>,
 ) -> PyResult<Bound<'_, PyAny>> {
     future_into_py(py, async move {
         let mut builder = lancedb::connect(&uri);
@@ -582,6 +583,11 @@ pub fn connect(
         if let Some(client_config) = client_config {
             builder = builder.client_config(client_config.into());
         }
+        if let Some(oauth_config) = oauth_config {
+            let config: lancedb::remote::oauth::OAuthConfig =
+                oauth_config.try_into().infer_error()?;
+            builder = builder.oauth_config(config);
+        }
         if let Some(session) = session {
             builder = builder.session(session.inner.clone());
         }
@@ -610,24 +616,38 @@ pub fn connect_namespace_client(
     namespace_client_impl: Option<String>,
     namespace_client_properties: Option<HashMap<String, String>>,
 ) -> PyResult<Connection> {
-    let namespace_client = extract_namespace_arc(py, namespace_client)?;
     let read_consistency_interval = read_consistency_interval.map(Duration::from_secs_f64);
     let namespace_client_pushdown_operations =
         parse_namespace_client_pushdown_operations(namespace_client_pushdown_operations)?;
-    let ns_impl = namespace_client_impl.unwrap_or_else(|| "python".to_string());
     let ns_properties = namespace_client_properties.unwrap_or_default();
     let storage_options = storage_options.unwrap_or_default();
     let session = session.map(|s| s.inner.clone());
 
-    let database = LanceNamespaceDatabase::from_namespace_client(
+    // Prefer building the namespace natively from (impl, properties) so the
-        namespace_client,
+    // read-freshness provider installed
-        ns_impl,
+    let database = if build_namespace_natively(namespace_client_impl.as_deref(), &ns_properties) {
-        ns_properties,
+        let ns_impl = namespace_client_impl.expect("impl present per build_namespace_natively");
-        storage_options,
+        crate::runtime::block_on(LanceNamespaceDatabase::connect(
-        read_consistency_interval,
+            &ns_impl,
-        session,
+            ns_properties,
-        namespace_client_pushdown_operations,
+            storage_options,
-    );
+            read_consistency_interval,
+            session,
+            namespace_client_pushdown_operations,
+        ))
+        .infer_error()?
+    } else {
+        let namespace_client = extract_namespace_arc(py, namespace_client)?;
+        LanceNamespaceDatabase::from_namespace_client(
+            namespace_client,
+            namespace_client_impl.unwrap_or_else(|| "python".to_string()),
+            ns_properties,
+            storage_options,
+            read_consistency_interval,
+            session,
+            namespace_client_pushdown_operations,
+        )
+    };
 
     Ok(Connection::new(LanceConnection::new(
         Arc::new(database),
@@ -635,6 +655,16 @@ pub fn connect_namespace_client(
     )))
 }
 
+/// Whether to build the namespace natively (from impl + properties) instead of
+/// wrapping a pre-built client. Native construction is required for the
+/// read-freshness provider to be installed
+fn build_namespace_natively(
+    namespace_client_impl: Option<&str>,
+    namespace_client_properties: &HashMap<String, String>,
+) -> bool {
+    matches!(namespace_client_impl, Some("rest")) && !namespace_client_properties.is_empty()
+}
+
 #[derive(FromPyObject)]
 pub struct PyClientConfig {
     user_agent: String,
@@ -733,3 +763,36 @@ impl From<PyClientConfig> for lancedb::remote::ClientConfig {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn props(pairs: &[(&str, &str)]) -> HashMap<String, String> {
+        pairs
+            .iter()
+            .map(|(k, v)| (k.to_string(), v.to_string()))
+            .collect()
+    }
+
+    #[test]
+    fn native_build_only_for_rest_with_properties() {
+        let rest = props(&[("uri", "http://localhost:10024")]);
+
+        // rest + non-empty properties -> build natively (installs the
+        // read-freshness provider so checkout_latest() busts the server cache).
+        assert!(build_namespace_natively(Some("rest"), &rest));
+
+        // dir is local (no server cache) -> wrap the pre-built client unchanged.
+        assert!(!build_namespace_natively(
+            Some("dir"),
+            &props(&[("root", "/tmp")])
+        ));
+
+        // No impl: only a pre-built client was handed in -> wrap it as-is.
+        assert!(!build_namespace_natively(None, &rest));
+
+        // rest but no properties: nothing to build a connection from -> wrap.
+        assert!(!build_namespace_natively(Some("rest"), &HashMap::new()));
+    }
+}

python/src/lib.rs

@@ -26,6 +26,7 @@ pub mod expr;
 pub mod header;
 pub mod index;
 pub mod namespace;
+pub mod oauth;
 pub mod permutation;
 pub mod query;
 pub mod runtime;

python/src/oauth.rs

@@ -0,0 +1,72 @@
+// SPDX-License-Identifier: Apache-2.0
+// SPDX-FileCopyrightText: Copyright The LanceDB Authors
+
+use pyo3::FromPyObject;
+
+use lancedb::error::Error;
+use lancedb::remote::oauth::{OAuthConfig, OAuthFlow};
+
+/// Python-side OAuth configuration, extracted via FromPyObject.
+/// Maps to `lancedb.remote.oauth.OAuthConfig` Python dataclass.
+#[derive(FromPyObject)]
+pub struct PyOAuthConfig {
+    pub issuer_url: String,
+    pub client_id: String,
+    pub scopes: Vec<String>,
+    pub flow: String,
+    pub client_secret: Option<String>,
+    pub managed_identity_client_id: Option<String>,
+    pub refresh_buffer_secs: Option<u64>,
+}
+
+impl TryFrom<PyOAuthConfig> for OAuthConfig {
+    type Error = Error;
+
+    fn try_from(py: PyOAuthConfig) -> Result<Self, Self::Error> {
+        let flow = match py.flow.as_str() {
+            "client_credentials" => OAuthFlow::ClientCredentials,
+            "azure_managed_identity" => OAuthFlow::AzureManagedIdentity {
+                client_id: py.managed_identity_client_id,
+            },
+            other => {
+                return Err(Error::InvalidInput {
+                    message: format!("Unknown OAuth flow type: {other}"),
+                });
+            }
+        };
+
+        Ok(Self {
+            issuer_url: py.issuer_url,
+            client_id: py.client_id,
+            client_secret: py.client_secret,
+            scopes: py.scopes,
+            flow,
+            refresh_buffer_secs: py.refresh_buffer_secs,
+        })
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_unknown_oauth_flow_returns_invalid_input() {
+        let config = PyOAuthConfig {
+            issuer_url: "https://issuer.example.com".to_string(),
+            client_id: "client-id".to_string(),
+            scopes: vec!["scope".to_string()],
+            flow: "typo".to_string(),
+            client_secret: None,
+            managed_identity_client_id: None,
+            refresh_buffer_secs: None,
+        };
+
+        let err = OAuthConfig::try_from(config).unwrap_err();
+        assert!(matches!(
+            err,
+            Error::InvalidInput { message }
+                if message == "Unknown OAuth flow type: typo"
+        ));
+    }
+}

python/src/runtime.rs

@@ -56,6 +56,15 @@ fn get_runtime() -> &'static runtime::Runtime {
     unsafe { &*new_ptr }
 }
 
+/// Block the current thread on a future using the shared runtime.
+///
+/// For sync `#[pyfunction]`s that need to drive an async operation (e.g.
+/// building a namespace client). Must not be called from within the runtime's
+/// own worker threads.
+pub fn block_on<F: std::future::Future>(fut: F) -> F::Output {
+    get_runtime().block_on(fut)
+}
+
 /// Runs in async-signal context after `fork()` in the child.  We can only
 /// touch atomics here; we deliberately leak the previous runtime because
 /// dropping a tokio `Runtime` would try to join its (now-dead) worker

python/tests/test_oauth.py

@@ -0,0 +1,33 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright The LanceDB Authors
+
+import importlib.util
+import sys
+from pathlib import Path
+
+
+def _load_oauth_module():
+    oauth_path = (
+        Path(__file__).parents[1] / "python" / "lancedb" / "remote" / "oauth.py"
+    )
+    spec = importlib.util.spec_from_file_location("lancedb_remote_oauth", oauth_path)
+    module = importlib.util.module_from_spec(spec)
+    assert spec.loader is not None
+    sys.modules[spec.name] = module
+    spec.loader.exec_module(module)
+    return module
+
+
+def test_oauth_config_repr_redacts_client_secret():
+    oauth = _load_oauth_module()
+
+    config = oauth.OAuthConfig(
+        issuer_url="https://issuer.example.com",
+        client_id="client-id",
+        scopes=["scope"],
+        client_secret="super-secret",
+    )
+
+    rendered = repr(config)
+    assert "super-secret" not in rendered
+    assert "client_secret" not in rendered

rust/lancedb/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "lancedb"
-version = "0.31.0-beta.1"
+version = "0.31.0-beta.3"
 edition.workspace = true
 description = "LanceDB: A serverless, low-latency vector database for AI applications"
 license.workspace = true
@@ -50,7 +50,7 @@ lance-namespace = { workspace = true }
 lance-namespace-impls = { workspace = true }
 moka = { workspace = true }
 pin-project = { workspace = true }
-tokio = { version = "1.23", features = ["rt-multi-thread"] }
+tokio = { version = "1.23", features = ["rt-multi-thread", "sync"] }
 log.workspace = true
 async-trait = "0"
 bytes = "1"
@@ -75,6 +75,7 @@ reqwest = { version = "0.12.0", default-features = false, features = [
     "stream",
 ], optional = true }
 http = { version = "1", optional = true } # Matching what is in reqwest
+urlencoding = { version = "2", optional = true }
 uuid = { version = "1.7.0", features = ["v4", "v5"] }
 polars-arrow = { version = ">=0.37,<0.40.0", optional = true }
 polars = { version = ">=0.37,<0.40.0", optional = true }
@@ -93,6 +94,7 @@ semver = { workspace = true }
 anyhow = "1"
 tempfile = "3.5.0"
 random_word = { version = "0.4.3", features = ["en"] }
+tokio = { version = "1.23", features = ["io-util", "macros", "net", "rt-multi-thread", "sync"] }
 uuid = { version = "1.7.0", features = ["v4"] }
 walkdir = "2"
 aws-sdk-dynamodb = { version = "1.55.0" }
@@ -129,7 +131,13 @@ huggingface = [
     "lance-namespace-impls/dir-huggingface",
 ]
 dynamodb = ["lance/dynamodb", "aws"]
-remote = ["dep:reqwest", "dep:http", "lance-namespace-impls/rest", "lance-namespace-impls/rest-adapter"]
+remote = [
+    "dep:reqwest",
+    "dep:http",
+    "dep:urlencoding",
+    "lance-namespace-impls/rest",
+    "lance-namespace-impls/rest-adapter",
+]
 fp16kernels = ["lance-linalg/fp16kernels"]
 s3-test = []
 bedrock = ["dep:aws-sdk-bedrockruntime"]

rust/lancedb/src/connection.rs

@@ -576,6 +576,9 @@ impl Connection {
     /// For LanceNamespaceDatabase, it is the underlying LanceNamespace.
     /// For ListingDatabase, it is the equivalent DirectoryNamespace.
     /// For RemoteDatabase, it is the equivalent RestNamespace.
+    ///
+    /// Remote connections using dynamic headers forward them through the
+    /// namespace client's per-request context provider.
     pub async fn namespace_client(&self) -> Result<Arc<dyn lance_namespace::LanceNamespace>> {
         self.internal.namespace_client().await
     }
@@ -584,6 +587,9 @@ impl Connection {
     /// Returns (impl_type, properties) where:
     /// - impl_type: "dir" for DirectoryNamespace, "rest" for RestNamespace
     /// - properties: configuration properties for the namespace
+    ///
+    /// Remote connections using dynamic headers cannot be exported because the
+    /// namespace client config only carries static headers.
     pub async fn namespace_client_config(
         &self,
     ) -> Result<(String, std::collections::HashMap<String, String>)> {
@@ -661,6 +667,8 @@ pub struct ConnectRequest {
 pub struct ConnectBuilder {
     request: ConnectRequest,
     embedding_registry: Option<Arc<dyn EmbeddingRegistry>>,
+    #[cfg(feature = "remote")]
+    oauth_config: Option<crate::remote::OAuthConfig>,
 }
 
 #[cfg(feature = "remote")]
@@ -682,6 +690,8 @@ impl ConnectBuilder {
                 session: None,
             },
             embedding_registry: None,
+            #[cfg(feature = "remote")]
+            oauth_config: None,
         }
     }
 
@@ -770,6 +780,19 @@ impl ConnectBuilder {
         self
     }
 
+    /// Configure OAuth authentication for LanceDB Cloud/Enterprise.
+    ///
+    /// This creates an [`OAuthHeaderProvider`](crate::remote::OAuthHeaderProvider)
+    /// from the given config and sets it as the header provider. OAuth cannot
+    /// be combined with an API key or another header provider.
+    ///
+    /// Token acquisition and refresh are handled in Rust.
+    #[cfg(feature = "remote")]
+    pub fn oauth_config(mut self, config: crate::remote::OAuthConfig) -> Self {
+        self.oauth_config = Some(config);
+        self
+    }
+
     /// Provide a custom [`EmbeddingRegistry`] to use for this connection.
     pub fn embedding_registry(mut self, registry: Arc<dyn EmbeddingRegistry>) -> Self {
         self.embedding_registry = Some(registry);
@@ -915,9 +938,40 @@ impl ConnectBuilder {
         let region = options.region.ok_or_else(|| Error::InvalidInput {
             message: "A region is required when connecting to LanceDb Cloud".to_string(),
         })?;
-        let api_key = options.api_key.ok_or_else(|| Error::InvalidInput {
+        let api_key = match (&self.oauth_config, &options.api_key) {
-            message: "An api_key is required when connecting to LanceDb Cloud".to_string(),
+            (Some(_), None) => String::new(),
-        })?;
+            (Some(_), Some(_)) => {
+                return Err(Error::InvalidInput {
+                    message:
+                        "api_key and oauth_config cannot both be set when connecting to LanceDb Cloud"
+                            .to_string(),
+                });
+            }
+            (None, Some(key)) => key.clone(),
+            (None, None) => {
+                return Err(Error::InvalidInput {
+                    message:
+                        "An api_key or oauth_config is required when connecting to LanceDb Cloud"
+                            .to_string(),
+                });
+            }
+        };
+
+        if self.oauth_config.is_some() && self.request.client_config.header_provider.is_some() {
+            return Err(Error::InvalidInput {
+                message:
+                    "oauth_config and client_config.header_provider cannot both be set when connecting to LanceDb Cloud"
+                        .to_string(),
+            });
+        }
+
+        let mut client_config = self.request.client_config;
+
+        if let Some(oauth_config) = self.oauth_config {
+            let provider = crate::remote::OAuthHeaderProvider::new(oauth_config)?;
+            client_config.header_provider =
+                Some(Arc::new(provider) as Arc<dyn crate::remote::HeaderProvider>);
+        }
 
         let storage_options = StorageOptions(options.storage_options.clone());
         let internal = Arc::new(crate::remote::db::RemoteDatabase::try_new(
@@ -925,7 +979,7 @@ impl ConnectBuilder {
             &api_key,
             &region,
             options.host_override,
-            self.request.client_config,
+            client_config,
             storage_options.into(),
             self.request.read_consistency_interval,
         )?);
@@ -1234,6 +1288,83 @@ mod tests {
         assert_eq!(Some(&"EXPLICIT-VALUE".to_string()), options.get(opts_key));
     }
 
+    #[cfg(feature = "remote")]
+    #[tokio::test]
+    async fn test_connect_rejects_api_key_with_oauth_config() {
+        let oauth_config = crate::remote::OAuthConfig {
+            issuer_url: "https://issuer.example.com".to_string(),
+            client_id: "client-id".to_string(),
+            client_secret: Some("secret".to_string()),
+            scopes: vec!["scope".to_string()],
+            flow: crate::remote::OAuthFlow::ClientCredentials,
+            refresh_buffer_secs: None,
+        };
+
+        let result = ConnectBuilder::new("db://my-container/my-prefix")
+            .region("us-east-1")
+            .api_key("my-api-key")
+            .oauth_config(oauth_config)
+            .execute()
+            .await;
+
+        match result {
+            Err(Error::InvalidInput { message })
+                if message
+                    == "api_key and oauth_config cannot both be set when connecting to LanceDb Cloud" =>
+                {}
+            Err(err) => panic!("expected InvalidInput, got {err:?}"),
+            Ok(_) => panic!("expected api_key and oauth_config to be rejected"),
+        }
+    }
+
+    #[cfg(feature = "remote")]
+    #[tokio::test]
+    async fn test_connect_rejects_header_provider_with_oauth_config() {
+        #[derive(Debug)]
+        struct TestHeaderProvider;
+
+        #[async_trait::async_trait]
+        impl crate::remote::HeaderProvider for TestHeaderProvider {
+            async fn get_headers(&self) -> Result<HashMap<String, String>> {
+                Ok(HashMap::from([(
+                    "authorization".to_string(),
+                    "Bearer token".to_string(),
+                )]))
+            }
+        }
+
+        let oauth_config = crate::remote::OAuthConfig {
+            issuer_url: "https://issuer.example.com".to_string(),
+            client_id: "client-id".to_string(),
+            client_secret: Some("secret".to_string()),
+            scopes: vec!["scope".to_string()],
+            flow: crate::remote::OAuthFlow::ClientCredentials,
+            refresh_buffer_secs: None,
+        };
+        let client_config = crate::remote::ClientConfig {
+            header_provider: Some(
+                Arc::new(TestHeaderProvider) as Arc<dyn crate::remote::HeaderProvider>
+            ),
+            ..Default::default()
+        };
+
+        let result = ConnectBuilder::new("db://my-container/my-prefix")
+            .region("us-east-1")
+            .client_config(client_config)
+            .oauth_config(oauth_config)
+            .execute()
+            .await;
+
+        match result {
+            Err(Error::InvalidInput { message })
+                if message
+                    == "oauth_config and client_config.header_provider cannot both be set when connecting to LanceDb Cloud" =>
+                {}
+            Err(err) => panic!("expected InvalidInput, got {err:?}"),
+            Ok(_) => panic!("expected header_provider and oauth_config to be rejected"),
+        }
+    }
+
     #[cfg(not(windows))]
     #[tokio::test]
     async fn test_connect_relative() {

rust/lancedb/src/remote.rs

@@ -8,6 +8,7 @@
 
 pub(crate) mod client;
 pub(crate) mod db;
+pub mod oauth;
 mod retry;
 pub(crate) mod table;
 pub(crate) mod util;
@@ -20,3 +21,4 @@ const JSON_CONTENT_TYPE: &str = "application/json";
 
 pub use client::{ClientConfig, HeaderProvider, RetryConfig, TimeoutConfig, TlsConfig};
 pub use db::{RemoteDatabaseOptions, RemoteDatabaseOptionsBuilder};
+pub use oauth::{OAuthConfig, OAuthFlow, OAuthHeaderProvider};

rust/lancedb/src/remote/client.rs

@@ -459,12 +459,14 @@ impl<S: HttpSend> RestfulLanceDbClient<S> {
         config: &ClientConfig,
     ) -> Result<HeaderMap> {
         let mut headers = HeaderMap::new();
-        headers.insert(
+        if !api_key.is_empty() {
-            HeaderName::from_static("x-api-key"),
+            headers.insert(
-            HeaderValue::from_str(api_key).map_err(|_| Error::InvalidInput {
+                HeaderName::from_static("x-api-key"),
-                message: "non-ascii api key provided".to_string(),
+                HeaderValue::from_str(api_key).map_err(|_| Error::InvalidInput {
-            })?,
+                    message: "non-ascii api key provided".to_string(),
-        );
+                })?,
+            );
+        }
         if region == "local" {
             let host = format!("{}.local.api.lancedb.com", db_name);
             headers.insert(
@@ -1005,6 +1007,33 @@ mod tests {
         assert!(!config_tls.assert_hostname);
     }
 
+    #[test]
+    fn test_default_headers_skip_empty_api_key() {
+        let headers = RestfulLanceDbClient::<Sender>::default_headers(
+            "",
+            "us-east-1",
+            "db-name",
+            false,
+            &RemoteOptions::default(),
+            None,
+            &ClientConfig::default(),
+        )
+        .unwrap();
+        assert!(!headers.contains_key("x-api-key"));
+
+        let headers = RestfulLanceDbClient::<Sender>::default_headers(
+            "api-key",
+            "us-east-1",
+            "db-name",
+            false,
+            &RemoteOptions::default(),
+            None,
+            &ClientConfig::default(),
+        )
+        .unwrap();
+        assert_eq!(headers.get("x-api-key").unwrap(), "api-key");
+    }
+
     // Test implementation of HeaderProvider
     #[derive(Debug, Clone)]
     struct TestHeaderProvider {

rust/lancedb/src/remote/db.rs

@@ -7,6 +7,7 @@ use std::sync::Arc;
 use async_trait::async_trait;
 use http::StatusCode;
 use lance_io::object_store::StorageOptions;
+use lance_namespace_impls::{DynamicContextProvider, OperationInfo};
 use moka::future::Cache;
 use reqwest::header::CONTENT_TYPE;
 
@@ -26,7 +27,9 @@ use crate::remote::util::stream_as_body;
 use crate::table::BaseTable;
 
 use super::ARROW_STREAM_CONTENT_TYPE;
-use super::client::{ClientConfig, HttpSend, RequestResultExt, RestfulLanceDbClient, Sender};
+use super::client::{
+    ClientConfig, HeaderProvider, HttpSend, RequestResultExt, RestfulLanceDbClient, Sender,
+};
 use super::table::RemoteTable;
 use super::util::parse_server_version;
 
@@ -194,10 +197,66 @@ pub struct RemoteDatabase<S: HttpSend = Sender> {
     uri: String,
     /// Headers to pass to the namespace client for authentication
     namespace_headers: HashMap<String, String>,
+    namespace_context_provider: Option<Arc<dyn DynamicContextProvider>>,
     /// TLS configuration for mTLS support
     tls_config: Option<super::client::TlsConfig>,
 }
 
+#[derive(Clone)]
+struct NamespaceHeaderProviderContext {
+    header_provider: Arc<dyn HeaderProvider>,
+}
+
+impl std::fmt::Debug for NamespaceHeaderProviderContext {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("NamespaceHeaderProviderContext")
+            .field("header_provider", &"Some(...)")
+            .finish()
+    }
+}
+
+impl DynamicContextProvider for NamespaceHeaderProviderContext {
+    fn provide_context(&self, _info: &OperationInfo) -> HashMap<String, String> {
+        let header_provider = Arc::clone(&self.header_provider);
+        let handle = match std::thread::Builder::new()
+            .name("lancedb-namespace-headers".to_string())
+            .spawn(move || {
+                tokio::runtime::Builder::new_current_thread()
+                    .enable_all()
+                    .build()
+                    .map_err(|e| Error::Runtime {
+                        message: format!(
+                            "Failed to create runtime for namespace header provider: {e}"
+                        ),
+                    })?
+                    .block_on(header_provider.get_headers())
+            }) {
+            Ok(handle) => handle,
+            Err(err) => {
+                log::warn!("Failed to spawn dynamic namespace header provider thread: {err}");
+                return HashMap::new();
+            }
+        };
+
+        let headers = handle.join();
+
+        match headers {
+            Ok(Ok(headers)) => headers
+                .into_iter()
+                .map(|(key, value)| (format!("headers.{key}"), value))
+                .collect(),
+            Ok(Err(err)) => {
+                log::warn!("Failed to get dynamic namespace headers: {err}");
+                HashMap::new()
+            }
+            Err(_) => {
+                log::warn!("Dynamic namespace header provider panicked");
+                HashMap::new()
+            }
+        }
+    }
+}
+
 impl RemoteDatabase {
     pub fn try_new(
         uri: &str,
@@ -228,6 +287,16 @@ impl RemoteDatabase {
             })
             .collect();
 
+        let namespace_context_provider =
+            client_config
+                .header_provider
+                .as_ref()
+                .map(|header_provider| {
+                    Arc::new(NamespaceHeaderProviderContext {
+                        header_provider: Arc::clone(header_provider),
+                    }) as Arc<dyn DynamicContextProvider>
+                });
+
         let client = RestfulLanceDbClient::try_new(
             &parsed,
             region,
@@ -247,6 +316,7 @@ impl RemoteDatabase {
             table_cache,
             uri: uri.to_owned(),
             namespace_headers,
+            namespace_context_provider,
             tls_config: client_config.tls_config,
         })
     }
@@ -271,6 +341,7 @@ mod test_utils {
                 table_cache: Cache::new(0),
                 uri: "http://localhost".to_string(),
                 namespace_headers: HashMap::new(),
+                namespace_context_provider: None,
                 tls_config: None,
             }
         }
@@ -281,11 +352,18 @@ mod test_utils {
             T: Into<reqwest::Body>,
         {
             let client = client_with_handler_and_config(handler, config.clone());
+            let namespace_context_provider =
+                config.header_provider.as_ref().map(|header_provider| {
+                    Arc::new(NamespaceHeaderProviderContext {
+                        header_provider: Arc::clone(header_provider),
+                    }) as Arc<dyn DynamicContextProvider>
+                });
             Self {
                 client,
                 table_cache: Cache::new(0),
                 uri: "http://localhost".to_string(),
                 namespace_headers: config.extra_headers.clone(),
+                namespace_context_provider,
                 tls_config: config.tls_config.clone(),
             }
         }
@@ -759,9 +837,12 @@ impl<S: HttpSend> Database for RemoteDatabase<S> {
         // Create a RestNamespace pointing to the same remote host with the same authentication headers
         let mut builder = lance_namespace_impls::RestNamespaceBuilder::new(self.client.host())
             .delimiter(&self.client.id_delimiter)
-            // TODO: support header provider
             .headers(self.namespace_headers.clone());
 
+        if let Some(context_provider) = &self.namespace_context_provider {
+            builder = builder.context_provider(Arc::clone(context_provider));
+        }
+
         // Apply mTLS configuration if present
         if let Some(tls_config) = &self.tls_config {
             if let Some(cert_file) = &tls_config.cert_file {
@@ -781,6 +862,14 @@ impl<S: HttpSend> Database for RemoteDatabase<S> {
     }
 
     async fn namespace_client_config(&self) -> Result<(String, HashMap<String, String>)> {
+        if self.namespace_context_provider.is_some() {
+            return Err(Error::NotSupported {
+                message:
+                    "Cannot export a namespace client config when dynamic headers are configured; use LanceDB connection namespace methods instead"
+                        .to_string(),
+            });
+        }
+
         let mut properties = HashMap::new();
         properties.insert("uri".to_string(), self.client.host().to_string());
         properties.insert("delimiter".to_string(), self.client.id_delimiter.clone());
@@ -832,12 +921,13 @@ impl From<StorageOptions> for RemoteOptions {
 
 #[cfg(test)]
 mod tests {
-    use super::build_cache_key;
+    use super::{NamespaceHeaderProviderContext, build_cache_key};
     use std::collections::HashMap;
     use std::sync::{Arc, OnceLock};
 
     use arrow_array::{Int32Array, RecordBatch};
     use arrow_schema::{DataType, Field, Schema};
+    use lance_namespace_impls::{DynamicContextProvider, OperationInfo};
 
     use crate::connection::ConnectBuilder;
     use crate::{
@@ -1702,6 +1792,75 @@ mod tests {
         assert!(namespace_client.is_ok());
     }
 
+    #[test]
+    fn test_namespace_header_provider_context_maps_headers() {
+        #[derive(Debug)]
+        struct TestHeaderProvider;
+
+        #[async_trait::async_trait]
+        impl HeaderProvider for TestHeaderProvider {
+            async fn get_headers(&self) -> crate::Result<HashMap<String, String>> {
+                Ok(HashMap::from([(
+                    "authorization".to_string(),
+                    "Bearer token".to_string(),
+                )]))
+            }
+        }
+
+        let context_provider = NamespaceHeaderProviderContext {
+            header_provider: Arc::new(TestHeaderProvider) as Arc<dyn HeaderProvider>,
+        };
+
+        let context =
+            context_provider.provide_context(&OperationInfo::new("list_tables", "namespace"));
+
+        assert_eq!(
+            context.get("headers.authorization"),
+            Some(&"Bearer token".to_string())
+        );
+    }
+
+    #[tokio::test]
+    async fn test_namespace_client_supports_dynamic_headers() {
+        #[derive(Debug)]
+        struct TestHeaderProvider;
+
+        #[async_trait::async_trait]
+        impl HeaderProvider for TestHeaderProvider {
+            async fn get_headers(&self) -> crate::Result<HashMap<String, String>> {
+                Ok(HashMap::from([(
+                    "authorization".to_string(),
+                    "Bearer token".to_string(),
+                )]))
+            }
+        }
+
+        let client_config = ClientConfig {
+            header_provider: Some(Arc::new(TestHeaderProvider) as Arc<dyn HeaderProvider>),
+            ..Default::default()
+        };
+
+        let conn = Connection::new_with_handler_and_config(
+            |_| {
+                http::Response::builder()
+                    .status(200)
+                    .body(r#"{"tables": []}"#)
+                    .unwrap()
+            },
+            client_config,
+        );
+
+        let namespace_client = conn.namespace_client().await;
+        assert!(namespace_client.is_ok());
+
+        match conn.namespace_client_config().await {
+            Err(Error::NotSupported { message })
+                if message.contains("dynamic headers are configured") => {}
+            Err(err) => panic!("expected NotSupported, got {err:?}"),
+            Ok(_) => panic!("expected namespace_client_config to reject dynamic headers"),
+        }
+    }
+
     /// Integration tests using RestAdapter to run RemoteDatabase against a real namespace server
     mod rest_adapter_integration {
         use super::*;

rust/lancedb/src/remote/oauth.rs

@@ -0,0 +1,907 @@
+// SPDX-License-Identifier: Apache-2.0
+// SPDX-FileCopyrightText: Copyright The LanceDB Authors
+
+use std::collections::HashMap;
+use std::net::IpAddr;
+use std::sync::Arc;
+use std::time::{Duration, Instant};
+
+use async_trait::async_trait;
+use log::debug;
+use reqwest::Client;
+use serde::Deserialize;
+use tokio::sync::RwLock;
+
+use crate::error::{Error, Result};
+use crate::remote::client::HeaderProvider;
+
+const DEFAULT_REFRESH_BUFFER_SECS: u64 = 300;
+const DEFAULT_TOKEN_TTL_SECS: u64 = 3600;
+const AZURE_IMDS_ENDPOINT: &str = "http://169.254.169.254/metadata/identity/oauth2/token";
+const AZURE_IMDS_API_VERSION: &str = "2018-02-01";
+
+/// OAuth authentication flow configuration.
+#[derive(Debug, Clone)]
+pub enum OAuthFlow {
+    /// Client Credentials grant (service-to-service / M2M).
+    /// Requires `client_secret` in [`OAuthConfig`].
+    ClientCredentials,
+
+    /// Azure Managed Identity via IMDS.
+    /// Works on Azure VMs, AKS, App Service, and Azure Functions.
+    /// IMDS requests bypass proxy settings because the endpoint is link-local.
+    AzureManagedIdentity {
+        /// Client ID for user-assigned managed identity.
+        /// Omit for system-assigned managed identity.
+        client_id: Option<String>,
+    },
+}
+
+/// OAuth configuration for LanceDB authentication.
+///
+/// All token acquisition and refresh is handled in the Rust layer.
+/// Python and TypeScript bindings expose this as a plain config object.
+#[derive(Clone)]
+pub struct OAuthConfig {
+    /// OIDC issuer URL or OAuth authority URL.
+    /// For Azure: `https://login.microsoftonline.com/{tenant_id}/v2.0`
+    pub issuer_url: String,
+
+    /// Application / Client ID.
+    pub client_id: String,
+
+    /// Client secret (required for `ClientCredentials`, optional for others).
+    pub client_secret: Option<String>,
+
+    /// OAuth scopes to request.
+    /// For Azure managed identity, exactly one scope or resource is required.
+    /// For example: `["api://{app_id}/.default"]`
+    pub scopes: Vec<String>,
+
+    /// Authentication flow to use.
+    pub flow: OAuthFlow,
+
+    /// Seconds before token expiry to trigger proactive refresh (default: 300).
+    /// Keep this well below the token TTL; if it is greater than or equal to
+    /// the TTL, each request refreshes the token.
+    pub refresh_buffer_secs: Option<u64>,
+}
+
+impl std::fmt::Debug for OAuthConfig {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("OAuthConfig")
+            .field("issuer_url", &self.issuer_url)
+            .field("client_id", &self.client_id)
+            .field(
+                "client_secret",
+                &self.client_secret.as_deref().map(|_| "<redacted>"),
+            )
+            .field("scopes", &self.scopes)
+            .field("flow", &self.flow)
+            .field("refresh_buffer_secs", &self.refresh_buffer_secs)
+            .finish()
+    }
+}
+
+// -- OIDC Discovery --
+
+#[derive(Clone, Debug, Deserialize)]
+struct OidcDiscovery {
+    token_endpoint: String,
+}
+
+// -- Token Response --
+
+#[derive(Deserialize)]
+struct TokenResponse {
+    access_token: String,
+    /// Token lifetime in seconds.
+    /// Some providers (Azure IMDS) return this as a string, so we accept both.
+    #[serde(default, deserialize_with = "deserialize_optional_u64_or_string")]
+    expires_in: Option<u64>,
+    #[serde(default)]
+    #[allow(dead_code)]
+    token_type: Option<String>,
+}
+
+impl std::fmt::Debug for TokenResponse {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("TokenResponse")
+            .field("access_token", &"<redacted>")
+            .field("expires_in", &self.expires_in)
+            .field("token_type", &self.token_type)
+            .finish()
+    }
+}
+
+fn deserialize_optional_u64_or_string<'de, D>(
+    deserializer: D,
+) -> std::result::Result<Option<u64>, D::Error>
+where
+    D: serde::Deserializer<'de>,
+{
+    use serde::de;
+
+    struct U64OrString;
+    impl<'de> de::Visitor<'de> for U64OrString {
+        type Value = Option<u64>;
+
+        fn expecting(&self, formatter: &mut std::fmt::Formatter) -> std::fmt::Result {
+            formatter.write_str("an integer, an integer-valued float, a numeric string, or null")
+        }
+
+        fn visit_u64<E: de::Error>(self, v: u64) -> std::result::Result<Self::Value, E> {
+            Ok(Some(v))
+        }
+
+        fn visit_i64<E: de::Error>(self, v: i64) -> std::result::Result<Self::Value, E> {
+            if v < 0 {
+                return Err(E::custom(format!("invalid expires_in value: {v}")));
+            }
+            Ok(Some(v as u64))
+        }
+
+        fn visit_f64<E: de::Error>(self, v: f64) -> std::result::Result<Self::Value, E> {
+            if !v.is_finite() || v < 0.0 || v.fract() != 0.0 || v > u64::MAX as f64 {
+                return Err(E::custom(format!("invalid expires_in value: {v}")));
+            }
+            Ok(Some(v as u64))
+        }
+
+        fn visit_str<E: de::Error>(self, v: &str) -> std::result::Result<Self::Value, E> {
+            v.parse::<u64>().map(Some).map_err(de::Error::custom)
+        }
+
+        fn visit_none<E: de::Error>(self) -> std::result::Result<Self::Value, E> {
+            Ok(None)
+        }
+
+        fn visit_unit<E: de::Error>(self) -> std::result::Result<Self::Value, E> {
+            Ok(None)
+        }
+    }
+
+    deserializer.deserialize_any(U64OrString)
+}
+
+// -- Internal Token State --
+
+struct TokenState {
+    access_token: Option<String>,
+    expires_at: Option<Instant>,
+}
+
+impl TokenState {
+    fn new() -> Self {
+        Self {
+            access_token: None,
+            expires_at: None,
+        }
+    }
+
+    fn is_expired(&self, buffer: Duration) -> bool {
+        match (self.access_token.as_ref(), self.expires_at) {
+            (Some(_), Some(expires_at)) => Instant::now() + buffer >= expires_at,
+            (None, _) => true,
+            (Some(_), None) => true,
+        }
+    }
+
+    fn update(&mut self, resp: &TokenResponse) {
+        self.access_token = Some(resp.access_token.clone());
+        let expires_in = resp.expires_in.unwrap_or(DEFAULT_TOKEN_TTL_SECS);
+        self.expires_at = Some(Instant::now() + Duration::from_secs(expires_in));
+    }
+}
+
+#[async_trait]
+trait TokenSource: Send + Sync + std::fmt::Debug {
+    async fn fetch_token(&self) -> Result<TokenResponse>;
+}
+
+struct ClientCredentialsSource {
+    issuer_url: String,
+    client_id: String,
+    client_secret: String,
+    scopes: Vec<String>,
+    http_client: Client,
+    discovery: RwLock<Option<OidcDiscovery>>,
+}
+
+impl std::fmt::Debug for ClientCredentialsSource {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("ClientCredentialsSource")
+            .field("issuer_url", &self.issuer_url)
+            .field("client_id", &self.client_id)
+            .field("client_secret", &"<redacted>")
+            .field("scopes", &self.scopes)
+            .finish()
+    }
+}
+
+impl ClientCredentialsSource {
+    fn new(
+        issuer_url: String,
+        client_id: String,
+        client_secret: Option<String>,
+        scopes: Vec<String>,
+    ) -> Result<Self> {
+        let client_secret = client_secret.ok_or(Error::InvalidInput {
+            message: "client_secret is required for ClientCredentials flow".to_string(),
+        })?;
+        Self::validate_issuer_transport(&issuer_url)?;
+
+        let http_client = Client::builder()
+            .timeout(Duration::from_secs(30))
+            .build()
+            .map_err(|e| Error::Runtime {
+                message: format!("Failed to create HTTP client for OAuth: {e}"),
+            })?;
+
+        Ok(Self {
+            issuer_url,
+            client_id,
+            client_secret,
+            scopes,
+            http_client,
+            discovery: RwLock::new(None),
+        })
+    }
+
+    fn validate_issuer_transport(issuer_url: &str) -> Result<()> {
+        let issuer = url::Url::parse(issuer_url).map_err(|e| Error::InvalidInput {
+            message: format!("Invalid OAuth issuer_url: {e}"),
+        })?;
+
+        match issuer.scheme() {
+            "https" => Ok(()),
+            "http" if Self::is_loopback_issuer(&issuer) => Ok(()),
+            _ => Err(Error::InvalidInput {
+                message:
+                    "ClientCredentials OAuth issuer_url must use https, except for loopback hosts"
+                        .to_string(),
+            }),
+        }
+    }
+
+    fn is_loopback_issuer(issuer: &url::Url) -> bool {
+        let Some(host) = issuer.host_str() else {
+            return false;
+        };
+
+        host.eq_ignore_ascii_case("localhost")
+            || host
+                .parse::<IpAddr>()
+                .map(|addr| addr.is_loopback())
+                .unwrap_or(false)
+    }
+
+    async fn get_discovery(&self) -> Result<OidcDiscovery> {
+        {
+            let cached = self.discovery.read().await;
+            if let Some(ref disc) = *cached {
+                return Ok(disc.clone());
+            }
+        }
+
+        let mut cache = self.discovery.write().await;
+        // Double-check
+        if let Some(ref disc) = *cache {
+            return Ok(disc.clone());
+        }
+
+        let discovery_url = format!(
+            "{}/.well-known/openid-configuration",
+            self.issuer_url.trim_end_matches('/')
+        );
+
+        debug!("Fetching OIDC discovery from {}", discovery_url);
+
+        let resp = self
+            .http_client
+            .get(&discovery_url)
+            .send()
+            .await
+            .map_err(|e| Error::Runtime {
+                message: format!("Failed to fetch OIDC discovery document: {e}"),
+            })?;
+
+        if !resp.status().is_success() {
+            return Err(Error::Runtime {
+                message: format!(
+                    "OIDC discovery failed with status {}: {}",
+                    resp.status(),
+                    resp.text().await.unwrap_or_default()
+                ),
+            });
+        }
+
+        let disc: OidcDiscovery = resp.json().await.map_err(|e| Error::Runtime {
+            message: format!("Failed to parse OIDC discovery document: {e}"),
+        })?;
+
+        let result = disc.clone();
+
+        *cache = Some(disc);
+        Ok(result)
+    }
+
+    async fn get_token_endpoint(&self) -> Result<String> {
+        self.get_discovery().await.map(|disc| disc.token_endpoint)
+    }
+
+    fn scopes_string(&self) -> String {
+        self.scopes.join(" ")
+    }
+
+    async fn post_token_request(
+        &self,
+        endpoint: &str,
+        params: &[(&str, &str)],
+    ) -> Result<TokenResponse> {
+        let resp = self
+            .http_client
+            .post(endpoint)
+            .form(params)
+            .send()
+            .await
+            .map_err(|e| Error::Runtime {
+                message: format!("Token request to {endpoint} failed: {e}"),
+            })?;
+
+        if !resp.status().is_success() {
+            return Err(Error::Runtime {
+                message: format!(
+                    "Token request failed with status {}: {}",
+                    resp.status(),
+                    resp.text().await.unwrap_or_default()
+                ),
+            });
+        }
+
+        resp.json().await.map_err(|e| Error::Runtime {
+            message: format!("Failed to parse token response: {e}"),
+        })
+    }
+}
+
+#[async_trait]
+impl TokenSource for ClientCredentialsSource {
+    async fn fetch_token(&self) -> Result<TokenResponse> {
+        let token_endpoint = self.get_token_endpoint().await?;
+        let scope = self.scopes_string();
+        let params = [
+            ("grant_type", "client_credentials"),
+            ("client_id", self.client_id.as_str()),
+            ("client_secret", self.client_secret.as_str()),
+            ("scope", scope.as_str()),
+        ];
+
+        self.post_token_request(&token_endpoint, &params).await
+    }
+}
+
+struct AzureImdsSource {
+    client_id: Option<String>,
+    resource: String,
+    http_client: Client,
+}
+
+impl std::fmt::Debug for AzureImdsSource {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("AzureImdsSource")
+            .field("client_id", &self.client_id)
+            .field("resource", &self.resource)
+            .finish()
+    }
+}
+
+impl AzureImdsSource {
+    fn new(scopes: Vec<String>, client_id: Option<String>) -> Result<Self> {
+        let resource = Self::resource_from_scopes(&scopes)?;
+        let http_client = Client::builder()
+            .timeout(Duration::from_secs(30))
+            .no_proxy()
+            .build()
+            .map_err(|e| Error::Runtime {
+                message: format!("Failed to create HTTP client for Azure IMDS OAuth: {e}"),
+            })?;
+
+        Ok(Self {
+            client_id,
+            resource,
+            http_client,
+        })
+    }
+
+    fn resource_from_scopes(scopes: &[String]) -> Result<String> {
+        let [scope] = scopes else {
+            return Err(Error::InvalidInput {
+                message: "AzureManagedIdentity flow requires exactly one OAuth scope or resource"
+                    .to_string(),
+            });
+        };
+
+        Ok(scope.strip_suffix("/.default").unwrap_or(scope).to_string())
+    }
+}
+
+#[async_trait]
+impl TokenSource for AzureImdsSource {
+    async fn fetch_token(&self) -> Result<TokenResponse> {
+        let mut url = format!(
+            "{AZURE_IMDS_ENDPOINT}?api-version={AZURE_IMDS_API_VERSION}&resource={}",
+            urlencoding::encode(&self.resource),
+        );
+        if let Some(cid) = self.client_id.as_deref() {
+            url.push_str(&format!("&client_id={}", urlencoding::encode(cid)));
+        }
+
+        let resp = self
+            .http_client
+            .get(&url)
+            .header("Metadata", "true")
+            .send()
+            .await
+            .map_err(|e| Error::Runtime {
+                message: format!("Azure IMDS request failed: {e}"),
+            })?;
+
+        if !resp.status().is_success() {
+            return Err(Error::Runtime {
+                message: format!(
+                    "Azure IMDS returned status {}: {}",
+                    resp.status(),
+                    resp.text().await.unwrap_or_default()
+                ),
+            });
+        }
+
+        resp.json().await.map_err(|e| Error::Runtime {
+            message: format!("Failed to parse IMDS token response: {e}"),
+        })
+    }
+}
+
+/// OAuth header provider that manages the full token lifecycle.
+///
+/// Implements [`HeaderProvider`] to inject `Authorization: Bearer <token>`
+/// headers into every LanceDB request, with automatic token refresh.
+pub struct OAuthHeaderProvider {
+    token_source: Box<dyn TokenSource>,
+    token_state: Arc<RwLock<TokenState>>,
+    refresh_buffer: Duration,
+}
+
+impl std::fmt::Debug for OAuthHeaderProvider {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("OAuthHeaderProvider")
+            .field("token_source", &self.token_source)
+            .finish()
+    }
+}
+
+impl OAuthHeaderProvider {
+    /// Create a new OAuth header provider from configuration.
+    pub fn new(config: OAuthConfig) -> Result<Self> {
+        let OAuthConfig {
+            issuer_url,
+            client_id,
+            client_secret,
+            scopes,
+            flow,
+            refresh_buffer_secs,
+        } = config;
+
+        if scopes.is_empty() {
+            return Err(Error::InvalidInput {
+                message: "At least one OAuth scope is required".to_string(),
+            });
+        }
+
+        let refresh_buffer =
+            Duration::from_secs(refresh_buffer_secs.unwrap_or(DEFAULT_REFRESH_BUFFER_SECS));
+        let token_source: Box<dyn TokenSource> = match flow {
+            OAuthFlow::ClientCredentials => Box::new(ClientCredentialsSource::new(
+                issuer_url,
+                client_id,
+                client_secret,
+                scopes,
+            )?),
+            OAuthFlow::AzureManagedIdentity { client_id } => {
+                Box::new(AzureImdsSource::new(scopes, client_id)?)
+            }
+        };
+
+        Ok(Self {
+            token_source,
+            token_state: Arc::new(RwLock::new(TokenState::new())),
+            refresh_buffer,
+        })
+    }
+
+    /// Get a valid access token, refreshing if necessary.
+    async fn get_valid_token(&self) -> Result<String> {
+        // Fast path: check if current token is still valid
+        {
+            let state = self.token_state.read().await;
+            if !state.is_expired(self.refresh_buffer)
+                && let Some(ref token) = state.access_token
+            {
+                return Ok(token.clone());
+            }
+        }
+
+        // Slow path: acquire or refresh token
+        let mut state = self.token_state.write().await;
+
+        // Double-check after acquiring write lock
+        if !state.is_expired(self.refresh_buffer)
+            && let Some(ref token) = state.access_token
+        {
+            return Ok(token.clone());
+        }
+
+        debug!("Acquiring new OAuth token via {:?}", self.token_source);
+        let resp = self.token_source.fetch_token().await?;
+
+        state.update(&resp);
+        Ok(resp.access_token)
+    }
+}
+
+#[async_trait]
+impl HeaderProvider for OAuthHeaderProvider {
+    async fn get_headers(&self) -> Result<HashMap<String, String>> {
+        let token = self.get_valid_token().await?;
+        Ok(HashMap::from([(
+            "authorization".to_string(),
+            format!("Bearer {token}"),
+        )]))
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::sync::atomic::{AtomicUsize, Ordering};
+
+    use tokio::io::{AsyncReadExt, AsyncWriteExt};
+    use tokio::net::{TcpListener, TcpStream};
+    use tokio::task::JoinHandle;
+
+    #[test]
+    fn test_token_state_expiry() {
+        let mut state = TokenState::new();
+        assert!(state.is_expired(Duration::from_secs(0)));
+
+        state.access_token = Some("tok".to_string());
+        state.expires_at = Some(Instant::now() + Duration::from_secs(600));
+        assert!(!state.is_expired(Duration::from_secs(300)));
+        assert!(state.is_expired(Duration::from_secs(601)));
+
+        state.expires_at = None;
+        assert!(state.is_expired(Duration::from_secs(0)));
+    }
+
+    #[test]
+    fn test_token_state_uses_default_expiry() {
+        let mut state = TokenState::new();
+        let response = TokenResponse {
+            access_token: "tok".to_string(),
+            expires_in: None,
+            token_type: None,
+        };
+
+        state.update(&response);
+
+        assert!(!state.is_expired(Duration::from_secs(DEFAULT_TOKEN_TTL_SECS - 1)));
+        assert!(state.is_expired(Duration::from_secs(DEFAULT_TOKEN_TTL_SECS + 1)));
+    }
+
+    #[test]
+    fn test_token_response_accepts_float_expires_in() {
+        let response: TokenResponse =
+            serde_json::from_str(r#"{"access_token":"tok","expires_in":3600.0}"#).unwrap();
+
+        assert_eq!(response.expires_in, Some(3600));
+    }
+
+    #[test]
+    fn test_token_response_rejects_negative_expires_in() {
+        let err =
+            serde_json::from_str::<TokenResponse>(r#"{"access_token":"tok","expires_in":-1}"#)
+                .unwrap_err();
+
+        assert!(err.to_string().contains("invalid expires_in value: -1"));
+    }
+
+    #[test]
+    fn test_token_response_debug_redacts_access_token() {
+        let response = TokenResponse {
+            access_token: "secret-token".to_string(),
+            expires_in: Some(3600),
+            token_type: Some("Bearer".to_string()),
+        };
+
+        let debug = format!("{response:?}");
+        assert!(!debug.contains("secret-token"));
+        assert!(debug.contains("access_token: \"<redacted>\""));
+    }
+
+    #[test]
+    fn test_scopes_string() {
+        let source = ClientCredentialsSource::new(
+            "https://login.microsoftonline.com/tenant/v2.0".to_string(),
+            "app-id".to_string(),
+            Some("secret".to_string()),
+            vec!["scope1".to_string(), "scope2".to_string()],
+        )
+        .unwrap();
+
+        assert_eq!(source.scopes_string(), "scope1 scope2");
+    }
+
+    #[test]
+    fn test_oauth_config_debug_redacts_client_secret() {
+        let config = OAuthConfig {
+            issuer_url: "https://issuer.example.com".to_string(),
+            client_id: "client-id".to_string(),
+            client_secret: Some("super-secret".to_string()),
+            scopes: vec!["scope".to_string()],
+            flow: OAuthFlow::ClientCredentials,
+            refresh_buffer_secs: None,
+        };
+
+        let debug = format!("{config:?}");
+        assert!(!debug.contains("super-secret"));
+        assert!(debug.contains("client_secret: Some(\"<redacted>\")"));
+    }
+
+    #[test]
+    fn test_oauth_header_provider_debug_redacts_client_secret() {
+        let config = OAuthConfig {
+            issuer_url: "https://issuer.example.com".to_string(),
+            client_id: "client-id".to_string(),
+            client_secret: Some("super-secret".to_string()),
+            scopes: vec!["scope".to_string()],
+            flow: OAuthFlow::ClientCredentials,
+            refresh_buffer_secs: None,
+        };
+
+        let provider = OAuthHeaderProvider::new(config).unwrap();
+        let debug = format!("{provider:?}");
+        assert!(!debug.contains("super-secret"));
+        assert!(debug.contains("client_secret: \"<redacted>\""));
+    }
+
+    #[test]
+    fn test_managed_identity_resource_from_default_scope() {
+        assert_eq!(
+            AzureImdsSource::resource_from_scopes(&["api://test/.default".to_string()]).unwrap(),
+            "api://test"
+        );
+    }
+
+    #[test]
+    fn test_managed_identity_resource_without_default_suffix() {
+        assert_eq!(
+            AzureImdsSource::resource_from_scopes(&["api://test".to_string()]).unwrap(),
+            "api://test"
+        );
+    }
+
+    #[test]
+    fn test_managed_identity_rejects_multiple_scopes() {
+        let config = OAuthConfig {
+            issuer_url: "https://login.microsoftonline.com/tenant/v2.0".to_string(),
+            client_id: "app-id".to_string(),
+            client_secret: None,
+            scopes: vec![
+                "api://test-a/.default".to_string(),
+                "api://test-b/.default".to_string(),
+            ],
+            flow: OAuthFlow::AzureManagedIdentity { client_id: None },
+            refresh_buffer_secs: None,
+        };
+        assert!(OAuthHeaderProvider::new(config).is_err());
+    }
+
+    #[tokio::test]
+    async fn test_token_endpoint_requires_discovery_success() {
+        let (issuer_url, server) = spawn_discovery_error_server().await;
+        let source = ClientCredentialsSource::new(
+            issuer_url,
+            "client-id".to_string(),
+            Some("secret".to_string()),
+            vec!["scope".to_string()],
+        )
+        .unwrap();
+
+        let err = source.get_token_endpoint().await.unwrap_err();
+        assert!(matches!(
+            err,
+            Error::Runtime { message }
+                if message.contains("OIDC discovery failed with status 503")
+        ));
+        server.await.unwrap();
+    }
+
+    #[test]
+    fn test_client_credentials_requires_secret() {
+        let config = OAuthConfig {
+            issuer_url: "https://login.microsoftonline.com/tenant/v2.0".to_string(),
+            client_id: "app-id".to_string(),
+            client_secret: None,
+            scopes: vec!["scope".to_string()],
+            flow: OAuthFlow::ClientCredentials,
+            refresh_buffer_secs: None,
+        };
+        assert!(OAuthHeaderProvider::new(config).is_err());
+    }
+
+    #[test]
+    fn test_client_credentials_rejects_insecure_non_loopback_issuer() {
+        let config = OAuthConfig {
+            issuer_url: "http://issuer.example.com".to_string(),
+            client_id: "app-id".to_string(),
+            client_secret: Some("secret".to_string()),
+            scopes: vec!["scope".to_string()],
+            flow: OAuthFlow::ClientCredentials,
+            refresh_buffer_secs: None,
+        };
+
+        let err = OAuthHeaderProvider::new(config).unwrap_err();
+        assert!(matches!(
+            err,
+            Error::InvalidInput { message }
+                if message == "ClientCredentials OAuth issuer_url must use https, except for loopback hosts"
+        ));
+    }
+
+    #[test]
+    fn test_empty_scopes_rejected() {
+        let config = OAuthConfig {
+            issuer_url: "https://login.microsoftonline.com/tenant/v2.0".to_string(),
+            client_id: "app-id".to_string(),
+            client_secret: None,
+            scopes: vec![],
+            flow: OAuthFlow::AzureManagedIdentity { client_id: None },
+            refresh_buffer_secs: None,
+        };
+        assert!(OAuthHeaderProvider::new(config).is_err());
+    }
+
+    #[tokio::test]
+    async fn test_client_credentials_token_lifecycle() {
+        let (issuer_url, token_requests, server) = spawn_oauth_server().await;
+        let config = OAuthConfig {
+            issuer_url,
+            client_id: "client-id".to_string(),
+            client_secret: Some("secret".to_string()),
+            scopes: vec!["scope".to_string()],
+            flow: OAuthFlow::ClientCredentials,
+            refresh_buffer_secs: Some(0),
+        };
+        let provider = OAuthHeaderProvider::new(config).unwrap();
+
+        let headers = provider.get_headers().await.unwrap();
+        assert_eq!(headers.get("authorization").unwrap(), "Bearer token-1");
+        assert_eq!(token_requests.load(Ordering::SeqCst), 1);
+
+        let headers = provider.get_headers().await.unwrap();
+        assert_eq!(headers.get("authorization").unwrap(), "Bearer token-1");
+        assert_eq!(token_requests.load(Ordering::SeqCst), 1);
+
+        provider.token_state.write().await.expires_at =
+            Some(Instant::now() - Duration::from_secs(1));
+
+        let headers = provider.get_headers().await.unwrap();
+        assert_eq!(headers.get("authorization").unwrap(), "Bearer token-2");
+        assert_eq!(token_requests.load(Ordering::SeqCst), 2);
+
+        server.await.unwrap();
+    }
+
+    async fn spawn_oauth_server() -> (String, Arc<AtomicUsize>, JoinHandle<()>) {
+        let listener = TcpListener::bind("127.0.0.1:0").await.unwrap();
+        let addr = listener.local_addr().unwrap();
+        let issuer_url = format!("http://{addr}");
+        let token_requests = Arc::new(AtomicUsize::new(0));
+        let server_token_requests = Arc::clone(&token_requests);
+
+        let server = tokio::spawn(async move {
+            for _ in 0..3 {
+                let (mut stream, _) = listener.accept().await.unwrap();
+                let (request_line, body) = read_http_request(&mut stream).await;
+
+                if request_line.starts_with("GET /.well-known/openid-configuration ") {
+                    let discovery = format!(r#"{{"token_endpoint":"http://{addr}/token"}}"#);
+                    write_json_response(&mut stream, "200 OK", &discovery).await;
+                } else if request_line.starts_with("POST /token ") {
+                    assert!(body.contains("grant_type=client_credentials"));
+                    assert!(body.contains("client_id=client-id"));
+                    assert!(body.contains("client_secret=secret"));
+                    assert!(body.contains("scope=scope"));
+
+                    let token_num = server_token_requests.fetch_add(1, Ordering::SeqCst) + 1;
+                    let token = format!(
+                        r#"{{"access_token":"token-{token_num}","expires_in":3600,"token_type":"Bearer"}}"#
+                    );
+                    write_json_response(&mut stream, "200 OK", &token).await;
+                } else {
+                    write_json_response(&mut stream, "404 Not Found", "{}").await;
+                }
+            }
+        });
+
+        (issuer_url, token_requests, server)
+    }
+
+    async fn spawn_discovery_error_server() -> (String, JoinHandle<()>) {
+        let listener = TcpListener::bind("127.0.0.1:0").await.unwrap();
+        let addr = listener.local_addr().unwrap();
+        let issuer_url = format!("http://{addr}");
+
+        let server = tokio::spawn(async move {
+            let (mut stream, _) = listener.accept().await.unwrap();
+            let (request_line, _) = read_http_request(&mut stream).await;
+            assert!(request_line.starts_with("GET /.well-known/openid-configuration "));
+            write_json_response(&mut stream, "503 Service Unavailable", "{}").await;
+        });
+
+        (issuer_url, server)
+    }
+
+    async fn read_http_request(stream: &mut TcpStream) -> (String, String) {
+        let mut buffer = Vec::new();
+        let mut header_end = None;
+
+        while header_end.is_none() {
+            let mut chunk = [0; 1024];
+            let read = stream.read(&mut chunk).await.unwrap();
+            assert_ne!(read, 0, "connection closed before request headers");
+            buffer.extend_from_slice(&chunk[..read]);
+            header_end = find_subsequence(&buffer, b"\r\n\r\n").map(|pos| pos + 4);
+        }
+
+        let header_end = header_end.unwrap();
+        let headers = String::from_utf8_lossy(&buffer[..header_end]).to_string();
+        let request_line = headers.lines().next().unwrap_or_default().to_string();
+        let content_length = headers
+            .lines()
+            .find_map(|line| {
+                let (name, value) = line.split_once(':')?;
+                name.eq_ignore_ascii_case("content-length")
+                    .then(|| value.trim().parse::<usize>().ok())
+                    .flatten()
+            })
+            .unwrap_or(0);
+
+        while buffer.len() < header_end + content_length {
+            let mut chunk = [0; 1024];
+            let read = stream.read(&mut chunk).await.unwrap();
+            assert_ne!(read, 0, "connection closed before request body");
+            buffer.extend_from_slice(&chunk[..read]);
+        }
+
+        let body =
+            String::from_utf8_lossy(&buffer[header_end..header_end + content_length]).to_string();
+
+        (request_line, body)
+    }
+
+    fn find_subsequence(haystack: &[u8], needle: &[u8]) -> Option<usize> {
+        haystack
+            .windows(needle.len())
+            .position(|window| window == needle)
+    }
+
+    async fn write_json_response(stream: &mut TcpStream, status: &str, body: &str) {
+        let response = format!(
+            "HTTP/1.1 {status}\r\ncontent-type: application/json\r\ncontent-length: {}\r\nconnection: close\r\n\r\n{body}",
+            body.len()
+        );
+        stream.write_all(response.as_bytes()).await.unwrap();
+    }
+}

rust/lancedb/src/table/query.rs

@@ -579,24 +579,45 @@ fn array_to_f32_vec(arr: &Arc<dyn arrow_array::Array>) -> Result<Vec<f32>> {
     })
 }
 
+/// Magic bytes that prefix (and suffix) the Arrow IPC *file* format.
+const ARROW_IPC_FILE_MAGIC: &[u8] = b"ARROW1";
+
 /// Parse Arrow IPC response from the namespace server.
+///
+/// The server may return either the Arrow IPC *file* format or the *stream*
+/// format. REST/phalanx returns the file format (it begins with the `ARROW1`
+/// magic); reading that with a `StreamReader` fails with "failed to fill whole
+/// buffer". Detect the magic and pick the matching reader so both are handled.
 async fn parse_arrow_ipc_response(bytes: bytes::Bytes) -> Result<DatasetRecordBatchStream> {
-    use arrow_ipc::reader::StreamReader;
+    use arrow_ipc::reader::{FileReader, StreamReader};
     use std::io::Cursor;
 
-    let cursor = Cursor::new(bytes);
+    let (schema, batches) = if bytes.starts_with(ARROW_IPC_FILE_MAGIC) {
-    let reader = StreamReader::try_new(cursor, None).map_err(|e| Error::Runtime {
+        let reader = FileReader::try_new(Cursor::new(bytes), None).map_err(|e| Error::Runtime {
-        message: format!("Failed to parse Arrow IPC response: {}", e),
+            message: format!("Failed to parse Arrow IPC file response: {}", e),
-    })?;
-
-    // Collect all record batches
-    let schema = reader.schema();
-    let batches: Vec<_> = reader
-        .into_iter()
-        .collect::<std::result::Result<Vec<_>, _>>()
-        .map_err(|e| Error::Runtime {
-            message: format!("Failed to read Arrow IPC batches: {}", e),
         })?;
+        let schema = reader.schema();
+        let batches = reader
+            .into_iter()
+            .collect::<std::result::Result<Vec<_>, _>>()
+            .map_err(|e| Error::Runtime {
+                message: format!("Failed to read Arrow IPC file batches: {}", e),
+            })?;
+        (schema, batches)
+    } else {
+        let reader =
+            StreamReader::try_new(Cursor::new(bytes), None).map_err(|e| Error::Runtime {
+                message: format!("Failed to parse Arrow IPC response: {}", e),
+            })?;
+        let schema = reader.schema();
+        let batches = reader
+            .into_iter()
+            .collect::<std::result::Result<Vec<_>, _>>()
+            .map_err(|e| Error::Runtime {
+                message: format!("Failed to read Arrow IPC batches: {}", e),
+            })?;
+        (schema, batches)
+    };
 
     // Create a stream from the batches
     let stream = futures::stream::iter(batches.into_iter().map(Ok));
@@ -624,6 +645,59 @@ mod tests {
         FixedSizeListArray::try_new_from_values(Float32Array::from(values), dimension).unwrap()
     }
 
+    #[tokio::test]
+    async fn test_parse_arrow_ipc_response_handles_file_and_stream() {
+        use arrow_array::{Int32Array, RecordBatch};
+        use arrow_ipc::writer::{FileWriter, StreamWriter};
+        use arrow_schema::{DataType, Field, Schema};
+
+        let schema = Arc::new(Schema::new(vec![Field::new("id", DataType::Int32, false)]));
+        let batch = RecordBatch::try_new(
+            schema.clone(),
+            vec![Arc::new(Int32Array::from(vec![1, 2, 3])) as ArrayRef],
+        )
+        .unwrap();
+
+        // Arrow IPC *file* format -- what REST/phalanx returns. Previously this
+        // failed with "failed to fill whole buffer" because we used a StreamReader.
+        let mut file_buf = Vec::new();
+        {
+            let mut writer = FileWriter::try_new(&mut file_buf, &schema).unwrap();
+            writer.write(&batch).unwrap();
+            writer.finish().unwrap();
+        }
+        assert!(file_buf.starts_with(ARROW_IPC_FILE_MAGIC));
+        let rows: usize = parse_arrow_ipc_response(bytes::Bytes::from(file_buf))
+            .await
+            .unwrap()
+            .try_collect::<Vec<_>>()
+            .await
+            .unwrap()
+            .iter()
+            .map(|b| b.num_rows())
+            .sum();
+        assert_eq!(rows, 3);
+
+        // Arrow IPC *stream* format must still parse.
+        let mut stream_buf = Vec::new();
+        {
+            let mut writer = StreamWriter::try_new(&mut stream_buf, &schema).unwrap();
+            writer.write(&batch).unwrap();
+            writer.finish().unwrap();
+        }
+        assert!(!stream_buf.starts_with(ARROW_IPC_FILE_MAGIC));
+        let rows: usize = parse_arrow_ipc_response(bytes::Bytes::from(stream_buf))
+            .await
+            .unwrap()
+            .try_collect::<Vec<_>>()
+            .await
+            .unwrap()
+            .iter()
+            .map(|b| b.num_rows())
+            .sum();
+        assert_eq!(rows, 3);
+    }
+
     #[test]
     fn test_convert_to_namespace_query_vector() {
         let query_vector = Arc::new(Float32Array::from(vec![1.0, 2.0, 3.0, 4.0]));