fix: metric type for python/node search api (#1689)

node/src/remote/client.ts

@@ -17,6 +17,7 @@ import axios, { type AxiosResponse, type ResponseType } from 'axios'
 import { tableFromIPC, type Table as ArrowTable } from 'apache-arrow'
 
 import { type RemoteResponse, type RemoteRequest, Method } from '../middleware'
+import { MetricType } from '..'
 
 interface HttpLancedbClientMiddleware {
   onRemoteRequest(
@@ -152,6 +153,7 @@ export class HttpLancedbClient {
     refineFactor?: number,
     columns?: string[],
     filter?: string,
+    metricType?: MetricType,
     fastSearch?: boolean
   ): Promise<ArrowTable<any>> {
     const result = await this.post(
@@ -160,10 +162,11 @@ export class HttpLancedbClient {
         vector,
         k,
         nprobes,
-        refineFactor,
+        refine_factor: refineFactor,
         columns,
         filter,
         prefilter,
+        metric: metricType,
         fast_search: fastSearch
       },
       undefined,

node/src/remote/index.ts

@@ -239,6 +239,7 @@ export class RemoteQuery<T = number[]> extends Query<T> {
       (this as any)._refineFactor,
       (this as any)._select,
       (this as any)._filter,
+      (this as any)._metricType,
       (this as any)._fastSearch
     )
 

python/python/lancedb/query.py

@@ -576,12 +576,12 @@ class LanceVectorQueryBuilder(LanceQueryBuilder):
         self._reranker = None
         self._str_query = str_query
 
-    def metric(self, metric: Literal["L2", "cosine"]) -> LanceVectorQueryBuilder:
+    def metric(self, metric: Literal["L2", "cosine", "dot"]) -> LanceVectorQueryBuilder:
         """Set the distance metric to use.
 
         Parameters
         ----------
-        metric: "L2" or "cosine"
+        metric: "L2" or "cosine" or "dot"
             The distance metric to use. By default "L2" is used.
 
         Returns
@@ -589,7 +589,7 @@ class LanceVectorQueryBuilder(LanceQueryBuilder):
         LanceVectorQueryBuilder
             The LanceQueryBuilder object.
         """
-        self._metric = metric
+        self._metric = metric.lower()
         return self
 
     def nprobes(self, nprobes: int) -> LanceVectorQueryBuilder:

rust/lancedb/src/lib.rs

@@ -228,6 +228,7 @@ pub use table::Table;
 
 #[derive(Debug, Copy, Clone, PartialEq, Serialize, Deserialize)]
 #[non_exhaustive]
+#[serde(rename_all = "lowercase")]
 pub enum DistanceType {
     /// Euclidean distance. This is a very common distance metric that
     /// accounts for both magnitude and direction when determining the distance