Merge #4693

4693: Introduce distinct attributes at search time r=irevoire a=Kerollmops

This PR fixes #4611.

### To Do
- [x] Remove the `distinguishableAttributes` settings (not even a commit about that).
- [x] Use the `filterableAttributes` to be able to use the `distinct` parameter at search.
- [x] Work on the errors and make tests.

Co-authored-by: Clément Renault <clement@meilisearch.com>
Co-authored-by: Tamo <tamo@meilisearch.com>

meilisearch/tests/search/distinct.rs

@@ -107,6 +107,39 @@ static DOCUMENTS: Lazy<Value> = Lazy::new(|| {
     ])
 });
 
+static NESTED_DOCUMENTS: Lazy<Value> = Lazy::new(|| {
+    json!([
+      {
+        "id": 1,
+        "description": "Leather Jacket",
+        "brand": "Lee Jeans",
+        "product_id": "123456",
+        "color": { "main": "Brown", "pattern": "stripped" },
+      },
+      {
+        "id": 2,
+        "description": "Leather Jacket",
+        "brand": "Lee Jeans",
+        "product_id": "123456",
+        "color": { "main": "Black", "pattern": "stripped" },
+      },
+      {
+        "id": 3,
+        "description": "Leather Jacket",
+        "brand": "Lee Jeans",
+        "product_id": "123456",
+        "color": { "main": "Blue", "pattern": "used" },
+      },
+      {
+        "id": 4,
+        "description": "T-Shirt",
+        "brand": "Nike",
+        "product_id": "789012",
+        "color": { "main": "Blue", "pattern": "stripped" },
+      }
+    ])
+});
+
 static DOCUMENT_PRIMARY_KEY: &str = "id";
 static DOCUMENT_DISTINCT_KEY: &str = "product_id";
 
@@ -239,3 +272,35 @@ async fn distinct_search_with_pagination_no_ranking() {
     snapshot!(response["totalPages"], @"2");
     snapshot!(response["totalHits"], @"6");
 }
+
+#[actix_rt::test]
+async fn distinct_at_search_time() {
+    let server = Server::new().await;
+    let index = server.index("tamo");
+
+    let documents = NESTED_DOCUMENTS.clone();
+    index.add_documents(documents, Some(DOCUMENT_PRIMARY_KEY)).await;
+    let (task, _) = index.update_settings_filterable_attributes(json!(["color.main"])).await;
+    let task = index.wait_task(task.uid()).await;
+    snapshot!(task, name: "succeed");
+
+    fn get_hits(response: &Value) -> Vec<String> {
+        let hits_array = response["hits"]
+            .as_array()
+            .unwrap_or_else(|| panic!("{}", &serde_json::to_string_pretty(&response).unwrap()));
+        hits_array
+            .iter()
+            .map(|h| h[DOCUMENT_PRIMARY_KEY].as_number().unwrap().to_string())
+            .collect::<Vec<_>>()
+    }
+
+    let (response, code) =
+        index.search_post(json!({"page": 1, "hitsPerPage": 3, "distinct": "color.main"})).await;
+    let hits = get_hits(&response);
+    snapshot!(code, @"200 OK");
+    snapshot!(hits.len(), @"3");
+    snapshot!(format!("{:?}", hits), @r###"["1", "2", "3"]"###);
+    snapshot!(response["page"], @"1");
+    snapshot!(response["totalPages"], @"1");
+    snapshot!(response["totalHits"], @"3");
+}

meilisearch/tests/search/errors.rs

@@ -1140,3 +1140,66 @@ async fn search_on_unknown_field_plus_joker() {
         )
         .await;
 }
+
+#[actix_rt::test]
+async fn distinct_at_search_time() {
+    let server = Server::new().await;
+    let index = server.index("tamo");
+    let (task, _) = index.create(None).await;
+    let task = index.wait_task(task.uid()).await;
+    snapshot!(task, name: "task-succeed");
+
+    let (response, code) =
+        index.search_post(json!({"page": 0, "hitsPerPage": 2, "distinct": "doggo.truc"})).await;
+    snapshot!(code, @"400 Bad Request");
+    snapshot!(response, @r###"
+    {
+      "message": "Attribute `doggo.truc` is not filterable and thus, cannot be used as distinct attribute. This index does not have configured filterable attributes.",
+      "code": "invalid_search_distinct",
+      "type": "invalid_request",
+      "link": "https://docs.meilisearch.com/errors#invalid_search_distinct"
+    }
+    "###);
+
+    let (task, _) = index.update_settings_filterable_attributes(json!(["color", "machin"])).await;
+    index.wait_task(task.uid()).await;
+
+    let (response, code) =
+        index.search_post(json!({"page": 0, "hitsPerPage": 2, "distinct": "doggo.truc"})).await;
+    snapshot!(code, @"400 Bad Request");
+    snapshot!(response, @r###"
+    {
+      "message": "Attribute `doggo.truc` is not filterable and thus, cannot be used as distinct attribute. Available filterable attributes are: `color, machin`.",
+      "code": "invalid_search_distinct",
+      "type": "invalid_request",
+      "link": "https://docs.meilisearch.com/errors#invalid_search_distinct"
+    }
+    "###);
+
+    let (task, _) = index.update_settings_displayed_attributes(json!(["color"])).await;
+    index.wait_task(task.uid()).await;
+
+    let (response, code) =
+        index.search_post(json!({"page": 0, "hitsPerPage": 2, "distinct": "doggo.truc"})).await;
+    snapshot!(code, @"400 Bad Request");
+    snapshot!(response, @r###"
+    {
+      "message": "Attribute `doggo.truc` is not filterable and thus, cannot be used as distinct attribute. Available filterable attributes are: `color, <..hidden-attributes>`.",
+      "code": "invalid_search_distinct",
+      "type": "invalid_request",
+      "link": "https://docs.meilisearch.com/errors#invalid_search_distinct"
+    }
+    "###);
+
+    let (response, code) =
+        index.search_post(json!({"page": 0, "hitsPerPage": 2, "distinct": true})).await;
+    snapshot!(code, @"400 Bad Request");
+    snapshot!(response, @r###"
+    {
+      "message": "Invalid value type at `.distinct`: expected a string, but found a boolean: `true`",
+      "code": "invalid_search_distinct",
+      "type": "invalid_request",
+      "link": "https://docs.meilisearch.com/errors#invalid_search_distinct"
+    }
+    "###);
+}

meilisearch/tests/search/snapshots/distinct.rs/distinct_at_search_time/succeed.snap

@@ -0,0 +1,20 @@
+---
+source: meilisearch/tests/search/distinct.rs
+---
+{
+  "uid": 1,
+  "indexUid": "tamo",
+  "status": "succeeded",
+  "type": "settingsUpdate",
+  "canceledBy": null,
+  "details": {
+    "filterableAttributes": [
+      "color.main"
+    ]
+  },
+  "error": null,
+  "duration": "[duration]",
+  "enqueuedAt": "[date]",
+  "startedAt": "[date]",
+  "finishedAt": "[date]"
+}

meilisearch/tests/search/snapshots/errors.rs/distinct_at_search_time/task-succeed.snap

@@ -0,0 +1,18 @@
+---
+source: meilisearch/tests/search/errors.rs
+---
+{
+  "uid": 0,
+  "indexUid": "tamo",
+  "status": "succeeded",
+  "type": "indexCreation",
+  "canceledBy": null,
+  "details": {
+    "primaryKey": null
+  },
+  "error": null,
+  "duration": "[duration]",
+  "enqueuedAt": "[date]",
+  "startedAt": "[date]",
+  "finishedAt": "[date]"
+}