Add missing _routing field in SearchHit interface

CHANGELOG.md

@@ -32,6 +32,7 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 - Adds cluster.get-certs to copy admin certs out of the container ([#507](https://github.com/opensearch-project/opensearch-go/pull/507))
 - Adds the `Fields` field containing stored fields to the `DocumentGetResp` struct ([#526](https://github.com/opensearch-project/opensearch-go/pull/526))
 - Adds ism plugin ([#524](https://github.com/opensearch-project/opensearch-go/pull/524))
+- Adds the `Routing` field in SearchHit interface. ([#516](https://github.com/opensearch-project/opensearch-go/pull/516))
 
 ### Changed
 - Uses docker compose v2 instead of v1 ([#506](https://github.com/opensearch-project/opensearch-go/pull/506))

opensearchapi/api_search.go

@@ -89,6 +89,7 @@ func (r SearchResp) Inspect() Inspect {
 type SearchHit struct {
 	Index       string                  `json:"_index"`
 	ID          string                  `json:"_id"`
+	Routing     string                  `json:"_routing"`
 	Score       float32                 `json:"_score"`
 	Source      json.RawMessage         `json:"_source"`
 	Fields      json.RawMessage         `json:"fields"`

opensearchapi/api_search_test.go

@@ -110,3 +110,43 @@ func TestSearch(t *testing.T) {
 		assert.Equal(t, fmt.Sprintf("/%s/_search", index), httpReq.URL.Path)
 	})
 }
+
+func TestSearchWithRouting(t *testing.T) {
+	client, err := ostest.NewClient()
+	require.Nil(t, err)
+
+	index := "test-index-search"
+
+	_, err = client.Index(
+		nil,
+		opensearchapi.IndexReq{
+			DocumentID: "foo",
+			Index:      index,
+			Body:       strings.NewReader(`{"foo": "bar"}`),
+			Params:     opensearchapi.IndexParams{Refresh: "true", Routing: "foo"},
+		},
+	)
+	require.Nil(t, err)
+	t.Cleanup(func() {
+		client.Indices.Delete(nil, opensearchapi.IndicesDeleteReq{Indices: []string{index}})
+	})
+
+	t.Run("request to retrieve response with routing key", func(t *testing.T) {
+		resp, err := client.Search(nil, &opensearchapi.SearchReq{Indices: []string{index}, Body: strings.NewReader(`{
+		  "query": {
+			"match": {
+			  "foo": "bar"
+			}
+		  },
+		  "fields": [
+			"foo"
+		  ],
+		  "_source": false
+		}`)})
+		require.Nil(t, err)
+		assert.NotEmpty(t, resp.Hits.Hits)
+		assert.NotEmpty(t, resp.Hits.Hits[0].Fields)
+		assert.NotEmpty(t, resp.Hits.Hits[0].Routing)
+		assert.Equal(t, "foo", resp.Hits.Hits[0].Routing)
+	})
+}