feat: add native OAuth/OIDC authentication support

Add OAuthConfig and OAuthHeaderProvider to the Rust core with support
for five OAuth flows: ClientCredentials, AuthorizationCodePKCE,
DeviceCode, AzureManagedIdentity, and WorkloadIdentity. Token
acquisition and auto-refresh happen entirely in Rust.

Python and TypeScript expose OAuthConfig as a plain config object that
maps to the Rust header provider via FFI — no dynamic callbacks cross
the language boundary.

ConnectBuilder gains an oauth_config() method that replaces the API key
requirement when OAuth is configured.

nodejs/lancedb/index.ts

@@ -52,6 +52,7 @@ export {
   SplitHashOptions,
   SplitSequentialOptions,
   ShuffleOptions,
+  OAuthConfig as NativeOAuthConfig,
 } from "./native.js";
 
 export {
@@ -130,6 +131,8 @@ export {
   TokenResponse,
 } from "./header";
 
+export { OAuthConfig, OAuthFlowType } from "./oauth";
+
 export { MergeInsertBuilder, WriteExecutionOptions } from "./merge";
 
 export * as embedding from "./embedding";

nodejs/lancedb/oauth.ts

@@ -0,0 +1,76 @@
+// SPDX-License-Identifier: Apache-2.0
+// SPDX-FileCopyrightText: Copyright The LanceDB Authors
+
+/**
+ * OAuth authentication flow types.
+ */
+export enum OAuthFlowType {
+  /** Client Credentials grant (service-to-service / M2M). */
+  ClientCredentials = "client_credentials",
+  /** Azure Managed Identity via IMDS. */
+  AzureManagedIdentity = "azure_managed_identity",
+}
+
+/**
+ * OAuth configuration for LanceDB authentication.
+ *
+ * This is the public TypeScript OAuth configuration type. The generated
+ * `NativeOAuthConfig` type has the same runtime shape but is an implementation
+ * detail of the napi-rs binding.
+ *
+ * All token acquisition and refresh is handled in the Rust layer.
+ * This config is passed through to Rust via napi-rs.
+ *
+ * @example Client Credentials (service-to-service):
+ * ```typescript
+ * const config: OAuthConfig = {
+ *   issuerUrl: "https://login.microsoftonline.com/{tenant}/v2.0",
+ *   clientId: "app-id",
+ *   clientSecret: "secret",
+ *   scopes: ["api://lancedb-api/.default"],
+ * };
+ * ```
+ *
+ * @example Azure Managed Identity:
+ * ```typescript
+ * const config: OAuthConfig = {
+ *   issuerUrl: "https://login.microsoftonline.com/{tenant}/v2.0",
+ *   clientId: "app-id",
+ *   scopes: ["api://lancedb-api/.default"],
+ *   flow: OAuthFlowType.AzureManagedIdentity,
+ * };
+ * ```
+ */
+export interface OAuthConfig {
+  /**
+   * OIDC issuer URL or OAuth authority URL.
+   * For Azure: `https://login.microsoftonline.com/{tenant_id}/v2.0`
+   */
+  issuerUrl: string;
+
+  /** Application / Client ID. */
+  clientId: string;
+
+  /**
+   * OAuth scopes to request.
+   * For Azure managed identity, exactly one scope or resource is required.
+   * For example: `["api://{app_id}/.default"]`
+   */
+  scopes: string[];
+
+  /** Authentication flow (default: ClientCredentials). */
+  flow?: OAuthFlowType;
+
+  /** Client secret (required for ClientCredentials). */
+  clientSecret?: string;
+
+  /** Client ID for user-assigned managed identity (AzureManagedIdentity). */
+  managedIdentityClientId?: string;
+
+  /**
+   * 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.
+   */
+  refreshBufferSecs?: number;
+}

nodejs/src/connection.rs

@@ -112,6 +112,12 @@ impl Connection {
 
         builder = builder.client_config(rust_config);
 
+        if let Some(oauth_config) = options.oauth_config {
+            let config: lancedb::remote::oauth::OAuthConfig =
+                oauth_config.try_into().default_error()?;
+            builder = builder.oauth_config(config);
+        }
+
         if let Some(api_key) = options.api_key {
             builder = builder.api_key(&api_key);
         }

nodejs/src/lib.rs

@@ -65,6 +65,11 @@ pub struct ConnectionOptions {
     /// (For LanceDB cloud only): the host to use for LanceDB cloud. Used
     /// for testing purposes.
     pub host_override: Option<String>,
+    /// (For LanceDB cloud only): OAuth configuration for IdP-based
+    /// authentication (e.g., Azure Entra ID). When set, token acquisition
+    /// and refresh are handled entirely in Rust. TypeScript users should pass
+    /// the public `OAuthConfig` type exported from `@lancedb/lancedb`.
+    pub oauth_config: Option<remote::OAuthConfig>,
 }
 
 #[napi(object)]

nodejs/src/remote.rs

@@ -3,6 +3,7 @@
 
 use std::collections::HashMap;
 
+use lancedb::error::Error;
 use napi_derive::*;
 
 /// Timeout configuration for remote HTTP client.
@@ -140,6 +141,84 @@ impl From<TlsConfig> for lancedb::remote::TlsConfig {
     }
 }
 
+/// OAuth configuration for LanceDB authentication.
+///
+/// This is the generated napi-rs binding shape. TypeScript users should prefer
+/// the public `OAuthConfig` type exported from `@lancedb/lancedb`.
+///
+/// All token acquisition and refresh is handled in the Rust layer.
+#[napi(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,
+    /// 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: "client_credentials" or "azure_managed_identity"
+    pub flow: Option<String>,
+    /// Client secret (required for client_credentials).
+    pub client_secret: Option<String>,
+    /// Client ID for user-assigned managed identity (azure_managed_identity).
+    pub managed_identity_client_id: Option<String>,
+    /// 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.
+    pub refresh_buffer_secs: Option<u32>,
+}
+
+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("scopes", &self.scopes)
+            .field("flow", &self.flow)
+            .field(
+                "client_secret",
+                &self.client_secret.as_deref().map(|_| "<redacted>"),
+            )
+            .field(
+                "managed_identity_client_id",
+                &self.managed_identity_client_id,
+            )
+            .field("refresh_buffer_secs", &self.refresh_buffer_secs)
+            .finish()
+    }
+}
+
+impl TryFrom<OAuthConfig> for lancedb::remote::oauth::OAuthConfig {
+    type Error = Error;
+
+    fn try_from(config: OAuthConfig) -> Result<Self, Self::Error> {
+        use lancedb::remote::oauth::OAuthFlow;
+
+        let flow = match config.flow.as_deref().unwrap_or("client_credentials") {
+            "client_credentials" => OAuthFlow::ClientCredentials,
+            "azure_managed_identity" => OAuthFlow::AzureManagedIdentity {
+                client_id: config.managed_identity_client_id,
+            },
+            other => {
+                return Err(Error::InvalidInput {
+                    message: format!("Unknown OAuth flow type: {other}"),
+                });
+            }
+        };
+
+        Ok(Self {
+            issuer_url: config.issuer_url,
+            client_id: config.client_id,
+            client_secret: config.client_secret,
+            scopes: config.scopes,
+            flow,
+            refresh_buffer_secs: config.refresh_buffer_secs.map(|v| v as u64),
+        })
+    }
+}
+
 impl From<ClientConfig> for lancedb::remote::ClientConfig {
     fn from(config: ClientConfig) -> Self {
         Self {
@@ -156,3 +235,45 @@ impl From<ClientConfig> for lancedb::remote::ClientConfig {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_unknown_oauth_flow_returns_invalid_input() {
+        let config = OAuthConfig {
+            issuer_url: "https://issuer.example.com".to_string(),
+            client_id: "client-id".to_string(),
+            scopes: vec!["scope".to_string()],
+            flow: Some("typo".to_string()),
+            client_secret: None,
+            managed_identity_client_id: None,
+            refresh_buffer_secs: None,
+        };
+
+        let err = lancedb::remote::oauth::OAuthConfig::try_from(config).unwrap_err();
+        assert!(matches!(
+            err,
+            Error::InvalidInput { message }
+                if message == "Unknown OAuth flow type: typo"
+        ));
+    }
+
+    #[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(),
+            scopes: vec!["scope".to_string()],
+            flow: Some("client_credentials".to_string()),
+            client_secret: Some("super-secret".to_string()),
+            managed_identity_client_id: None,
+            refresh_buffer_secs: None,
+        };
+
+        let debug = format!("{config:?}");
+        assert!(!debug.contains("super-secret"));
+        assert!(debug.contains("client_secret: Some(\"<redacted>\")"));
+    }
+}