add unit test

crates/meilisearch/tests/settings/get_settings.rs

@@ -197,7 +197,7 @@ test_setting_routes!(
     {
       setting: vector_store,
       update_verb: patch,
-      default_value: "stable"
+      default_value: null
     },
 );
 

crates/meilisearch/tests/vector/mod.rs

@@ -6,11 +6,13 @@ mod openai;
 mod rest;
 mod settings;
 
+use std::collections::HashMap;
 use std::str::FromStr;
 
 use meili_snap::{json_string, snapshot};
 use meilisearch::option::MaxThreads;
 pub use rest::create_mock;
+use serde_json::Value;
 
 use crate::common::index::Index;
 use crate::common::{default_settings, GetAllDocumentsOptions, Server};
@@ -781,3 +783,90 @@ async fn add_remove_one_vector_4588() {
     }
     "#);
 }
+
+#[actix_rt::test]
+async fn change_backend() {
+    let server = Server::new().await;
+    let index = server.unique_index();
+    server.set_features(json!({"vectorStoreSetting": true})).await;
+    let (response, code) = index
+        .update_settings(json!({
+          "vectorStore": "stable"
+        }))
+        .await;
+    snapshot!(code, @"202 Accepted");
+    server.wait_task(response.uid()).await.succeeded();
+
+    let (response, code) = index
+        .update_settings(json!({
+          "embedders": {
+              "manual": {
+                  "source": "userProvided",
+                  "dimensions": 3,
+                  "binaryQuantized": false,
+              }
+          },
+        }))
+        .await;
+    snapshot!(code, @"202 Accepted");
+    server.wait_task(response.uid()).await.succeeded();
+
+    let documents = json!([
+      {"id": 0, "name": "kefir", "_vectors": { "manual": [-1.2, -2.3, 3.2] }},
+      {"id": 1, "name": "echo", "_vectors": { "manual": [2.5, 1.5, -130] }},
+    ]);
+    let (value, code) = index.add_documents(documents, None).await;
+    snapshot!(code, @"202 Accepted");
+    server.wait_task(value.uid()).await.succeeded();
+
+    // Make sure the documents are binary quantized
+    let (documents, _code) = index
+        .get_all_documents(GetAllDocumentsOptions { retrieve_vectors: true, ..Default::default() })
+        .await;
+    let stable_embeddings: HashMap<Value, Value> = documents["results"]
+        .as_array()
+        .unwrap()
+        .iter()
+        .map(|o| (o["id"].clone(), o["_vectors"]["manual"]["embeddings"].clone()))
+        .collect();
+
+    let (response, code) = index
+        .update_settings(json!({
+          "vectorStore": "experimental"
+        }))
+        .await;
+    snapshot!(code, @"202 Accepted");
+    server.wait_task(response.uid()).await.succeeded();
+
+    let (documents, _code) = index
+        .get_all_documents(GetAllDocumentsOptions { retrieve_vectors: true, ..Default::default() })
+        .await;
+
+    let experimental_embeddings: HashMap<Value, Value> = documents["results"]
+        .as_array()
+        .unwrap()
+        .iter()
+        .map(|o| (o["id"].clone().clone(), o["_vectors"]["manual"]["embeddings"].clone()))
+        .collect();
+
+    let (response, code) = index
+        .update_settings(json!({
+          "vectorStore": "stable"
+        }))
+        .await;
+    snapshot!(code, @"202 Accepted");
+    server.wait_task(response.uid()).await.succeeded();
+
+    let (documents, _code) = index
+        .get_all_documents(GetAllDocumentsOptions { retrieve_vectors: true, ..Default::default() })
+        .await;
+    let back_to_stable_embeddings: HashMap<Value, Value> = documents["results"]
+        .as_array()
+        .unwrap()
+        .iter()
+        .map(|o| (o["id"].clone(), o["_vectors"]["manual"]["embeddings"].clone()))
+        .collect();
+
+    assert_eq!(stable_embeddings, experimental_embeddings);
+    assert_eq!(experimental_embeddings, back_to_stable_embeddings);
+}