Merge #599

599: Accept distinct search parameter r=irevoire a=NoodleSamaChan

# Pull Request

## Related issue
#597

## What does this PR do?
#597

## PR checklist
Please check if your PR fulfills the following requirements:
- [x] Does this PR fix an existing issue, or have you listed the changes applied in the PR description (and why they are needed)?
- [x] Have you read the contributing guidelines?
- [x] Have you made sure that the title is accurate and descriptive of the changes?

Thank you so much for contributing to Meilisearch!


Co-authored-by: NoodleSamaChan <[email protected]>
Co-authored-by: NoodleSamaChan <[email protected]>

.code-samples.meilisearch.yaml

@@ -1704,3 +1704,29 @@ create_snapshot_1: |-
     .create_snapshot()
     .await
     .unwrap();
+search_parameter_reference_distinct_1: |-
+  let res = client
+    .index("INDEX_NAME")
+    .search()
+    .with_query("QUERY TERMS")
+    .with_distinct("ATTRIBUTE_A")
+    .execute()
+    .await
+    .unwrap();
+distinct_attribute_guide_filterable_1: |-
+  let task: TaskInfo = client
+    .index("products")
+    .settings()
+    .set_filterable_attributes(["product_id", "sku", "url"])
+    .execute()
+    .await
+    .unwrap();
+distinct_attribute_guide_distinct_parameter_1: |-
+  let res = client
+    .index("products")
+    .search()
+    .with_query("white shirt")
+    .with_distinct("sku")
+    .execute()
+    .await
+    .unwrap();

src/search.rs

@@ -338,6 +338,10 @@ pub struct SearchQuery<'a, Http: HttpClient> {
 
     #[serde(skip_serializing_if = "Option::is_none")]
     pub(crate) index_uid: Option<&'a str>,
+
+    ///Defines one attribute in the filterableAttributes list as a distinct attribute.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(crate) distinct: Option<&'a str>,
 }
 
 #[allow(missing_docs)]
@@ -367,6 +371,7 @@ impl<'a, Http: HttpClient> SearchQuery<'a, Http> {
             show_ranking_score_details: None,
             matching_strategy: None,
             index_uid: None,
+            distinct: None,
         }
     }
     pub fn with_query<'b>(&'b mut self, query: &'a str) -> &'b mut SearchQuery<'a, Http> {
@@ -559,6 +564,10 @@ impl<'a, Http: HttpClient> SearchQuery<'a, Http> {
         self.index_uid = Some(&self.index.uid);
         self
     }
+    pub fn with_distinct<'b>(&'b mut self, distinct: &'a str) -> &'b mut SearchQuery<'a, Http> {
+        self.distinct = Some(distinct);
+        self
+    }
     pub fn build(&mut self) -> SearchQuery<'a, Http> {
         self.clone()
     }
@@ -1182,6 +1191,20 @@ mod tests {
         Ok(())
     }
 
+    #[meilisearch_test]
+    async fn test_distinct(client: Client, index: Index) -> Result<(), Error> {
+        setup_test_index(&client, &index).await?;
+
+        let results = SearchQuery::new(&index)
+            .with_distinct("kind")
+            .execute::<Document>()
+            .await
+            .unwrap();
+
+        assert_eq!(results.hits.len(), 2);
+        Ok(())
+    }
+
     #[meilisearch_test]
     async fn test_generate_tenant_token_from_client(
         client: Client,