feat(vertexai): Add sample retail_v2_search_pagination

Author: amcolin

vertexai/retail/search_pagination.go

@@ -0,0 +1,88 @@
+// Copyright 2026 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package retail
+
+import (
+	"context"
+	"fmt"
+
+	retail "cloud.google.com/go/retail/apiv2"
+
+	retailpb "cloud.google.com/go/retail/apiv2/retailpb"
+)
+
+// [START retail_v2_search_pagination]
+// searchPagination method searches for products with pagination using Vertex AI Search for commerce.
+// Performs a search request, then uses the nextToken to get the next page.
+//
+// projectID: The Google Cloud project ID.
+// query: The search term for text search.
+// visitorID: A unique identifier for the user.
+func searchPagination(projectID, query, visitorID string) error {
+	ctx := context.Background()
+
+	client, err := retail.NewSearchClient(ctx)
+	if err != nil {
+		return fmt.Errorf("unable to create client: %w", err)
+	}
+	defer client.Close()
+
+	placement := fmt.Sprintf("projects/%s/locations/global/catalogs/default_catalog/placements/default_search", projectID)
+
+	// First page request
+	firstPageReq := &retailpb.SearchRequest{
+		Placement: placement,
+		Query:     query,
+		VisitorId: visitorID,
+		PageSize:  5,
+	}
+
+	it := client.Search(ctx, firstPageReq)
+
+	resp, err := it.Next()
+	if err != nil {
+		return fmt.Errorf("failed to fetch first page: %v", err)
+	}
+
+	fmt.Printf("First result from page 1: %s\n", resp.GetProduct().GetName())
+
+	nextToken := it.PageInfo().Token
+	if nextToken == "" {
+		fmt.Println("No more pages available")
+		return nil
+	}
+	fmt.Printf("Next page token: %s\n", nextToken)
+
+	// Second page request using PageToken
+	secondPageReq := &retailpb.SearchRequest{
+		Placement: placement,
+		Query:     query,
+		VisitorId: visitorID,
+		PageSize:  5,
+		PageToken: nextToken,
+	}
+
+	it2 := client.Search(ctx, secondPageReq)
+	resp2, err := it2.Next()
+	if err != nil {
+		return fmt.Errorf("failed to fetch first page: %v", err)
+	}
+
+	fmt.Printf("First result from page 2: %s\n", resp2.GetProduct().GetName())
+
+	return nil
+}
+
+// [END retail_v2_search_pagination]

vertexai/retail/search_pagination_test.go

@@ -0,0 +1,32 @@
+// Copyright 2026 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package retail
+
+import (
+	"testing"
+
+	"github.com/GoogleCloudPlatform/golang-samples/internal/testutil"
+)
+
+func Test_searchPagination(t *testing.T) {
+	tc := testutil.SystemTest(t)
+
+	query := ""
+	visitorID := "unique-visitor-id"
+
+	if err := searchPagination(tc.ProjectID, query, visitorID); err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+}

vertexai/retail/search_request.go

@@ -27,7 +27,7 @@ import (
 // [START retail_v2_search_request]
 // searchRequest method searches for products using Vertex AI Search for commerce.
 // Performs a search request for a specific placement.
-// Handles both text search (using query) and browse search (using page_categories).
+// Handles both text search (using query) and browse search (using pageCategories).
 //
 // projectID: The Google Cloud project ID.
 // query: The search term for text search.