feat(genai): Add samples for Content-cache and Text-generation (#5358)

* updated genai go sdk from 1.6.0 to 1.17.0 and fix broken test

* genai:updated go sdk from 1.6.0 to 1.17.0 and fix broken test

* genai: PR comments addressed

* genai: go mod tidy

* genai: textgen_with_routing test case commented out

* genai: textgen_with_routing test case commented out

* genai: added content_cache list sample

* genai: added textgen samples

* Update genai/content_cache/content_cache_test.go

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

* Update genai/text_generation/text_generation_examples_test.go

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

* Update content_cache_test.go

* genai: PR comments

---------

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>
Co-authored-by: Sampath Kumar <[email protected]>

Author: 3 people

genai/content_cache/content_cache_test.go

@@ -45,13 +45,19 @@ func TestContentCaching(t *testing.T) {
 		t.Errorf("updateContentCache: %v", err.Error())
 	}
 
-	// 3) Use cached content with a text prompt.
+	// 3) List and inspect the content cache.
+	err = listContentCache(buf)
+	if err != nil {
+		t.Errorf("listContentCache: %v", err.Error())
+	}
+
+	// 4) Use cached content with a text prompt.
 	err = useContentCacheWithTxt(buf, cacheName)
 	if err != nil {
 		t.Errorf("useContentCacheWithTxt: %v", err.Error())
 	}
 
-	// 4) Delete the content cache.
+	// 5) Delete the content cache.
 	buf.Reset()
 	err = deleteContentCache(buf, cacheName)
 	if err != nil {

genai/content_cache/contentcache_list.go

@@ -0,0 +1,75 @@
+// Copyright 2025 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 content_cache shows examples of using content caching with the GenAI SDK.
+package content_cache
+
+// [START googlegenaisdk_contentcache_list]
+import (
+	"context"
+	"fmt"
+	"io"
+	"net/http"
+	"time"
+
+	"google.golang.org/genai"
+)
+
+// listContentCache shows how to retrieve details about cached content.
+func listContentCache(w io.Writer) error {
+	ctx := context.Background()
+
+	client, err := genai.NewClient(ctx, &genai.ClientConfig{
+		HTTPOptions: genai.HTTPOptions{APIVersion: "v1"},
+	})
+	if err != nil {
+		return fmt.Errorf("failed to create genai client: %w", err)
+	}
+
+	// Retrieve cached content metadata
+	cache, err := client.Caches.List(ctx, &genai.ListCachedContentsConfig{
+		HTTPOptions: &genai.HTTPOptions{
+			Headers:    http.Header{"X-Custom-Header": []string{"example"}},
+			APIVersion: "v1",
+		},
+	})
+	if err != nil {
+		return fmt.Errorf("failed to get content cache: %w", err)
+	}
+
+	// Print basic info about the cached content
+	fmt.Fprintf(w, "Cache name: %s\n", cache.Name)
+	fmt.Fprintf(w, "Display name: %s\n", cache.Items[0].DisplayName)
+	fmt.Fprintf(w, "Model: %s\n", cache.Items[0].Model)
+	fmt.Fprintf(w, "Create time: %s\n", cache.Items[0].CreateTime.Format(time.RFC3339))
+	fmt.Fprintf(w, "Update time: %s\n", cache.Items[0].UpdateTime.Format(time.RFC3339))
+	fmt.Fprintf(w, "Expire time: %s (in %s)\n", cache.Items[0].ExpireTime.Format(time.RFC3339), time.Until(cache.Items[0].ExpireTime).Round(time.Second))
+
+	if cache.Items[0].UsageMetadata != nil {
+		fmt.Fprintf(w, "Usage metadata: %+v\n", cache.Items[0].UsageMetadata)
+	}
+
+	// Example response:
+	// Cache name: projects/111111111111/locations/us-central1/cachedContents/1234567890123456789
+	// Display name: product_recommendations_prompt
+	// Model: models/gemini-2.5-flash
+	// Create time: 2025-04-08T02:15:23Z
+	// Update time: 2025-04-08T03:05:11Z
+	// Expire time: 2025-04-20T03:05:11Z (in 167h59m59s)
+	// Usage metadata: &{AudioDurationSeconds:0 ImageCount:167 TextCount:153 TotalTokenCount:43124 VideoDurationSeconds:0}
+
+	return nil
+}
+
+// [END googlegenaisdk_contentcache_list]

genai/text_generation/text_generation_examples_test.go

@@ -173,7 +173,8 @@ func TestTextGeneration(t *testing.T) {
 		}
 	})
 
-	/*t.Run("generate with routing", func(t *testing.T) {
+	t.Run("generate with routing", func(t *testing.T) {
+		t.Skip("skipping because of model used in this test. The model 'model-optimizer-exp-04-09' is not consistently available in all test environments.")
 		buf.Reset()
 		err := generateWithRouting(buf)
 		if err != nil {
@@ -184,6 +185,58 @@ func TestTextGeneration(t *testing.T) {
 		if output == "" {
 			t.Error("expected non-empty output, got empty")
 		}
-	})*/
+	})
+
+	t.Run("generate chat stream with text prompt", func(t *testing.T) {
+		buf.Reset()
+		err := generateChatStreamWithText(buf)
+		if err != nil {
+			t.Fatalf("generateChatStreamWithText failed: %v", err)
+		}
+
+		output := buf.String()
+		if output == "" {
+			t.Error("expected non-empty output, got empty")
+		}
+	})
+
+	t.Run("generate Text With PDF", func(t *testing.T) {
+		buf.Reset()
+		err := generateTextWithPDF(buf)
+		if err != nil {
+			t.Fatalf("generateTextWithPDF failed: %v", err)
+		}
+
+		output := buf.String()
+		if output == "" {
+			t.Error("expected non-empty output, got empty")
+		}
+	})
+
+	t.Run("generate thinking with text prompt", func(t *testing.T) {
+		buf.Reset()
+		err := generateThinkingWithText(buf)
+		if err != nil {
+			t.Fatalf("generateThinkingWithText failed: %v", err)
+		}
+
+		output := buf.String()
+		if output == "" {
+			t.Error("expected non-empty output, got empty")
+		}
+	})
+
+	t.Run("generate with model optimizer", func(t *testing.T) {
+		buf.Reset()
+		err := generateModelOptimizerWithTxt(buf)
+		if err != nil {
+			t.Fatalf("generateModelOptimizerWithTxt failed: %v", err)
+		}
+
+		output := buf.String()
+		if output == "" {
+			t.Error("expected non-empty output, got empty")
+		}
+	})
 
 }

genai/text_generation/textgen_model_optimizer_with_txt.go

@@ -0,0 +1,73 @@
+// Copyright 2025 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 text_generation shows examples of generating text using the GenAI SDK.
+package text_generation
+
+// [START googlegenaisdk_model_optimizer_textgen_with_txt]
+import (
+	"context"
+	"fmt"
+	"io"
+
+	"google.golang.org/genai"
+)
+
+// generateModelOptimizerWithTxt shows how to generate text using a text prompt and model optimizer.
+func generateModelOptimizerWithTxt(w io.Writer) error {
+	ctx := context.Background()
+
+	clientConfig := &genai.ClientConfig{
+		HTTPOptions: genai.HTTPOptions{APIVersion: "v1beta1"},
+	}
+
+	client, err := genai.NewClient(ctx, clientConfig)
+
+	if err != nil {
+		return fmt.Errorf("failed to create genai client: %w", err)
+	}
+
+	modelSelectionConfig := &genai.ModelSelectionConfig{
+		FeatureSelectionPreference: genai.FeatureSelectionPreferenceBalanced,
+	}
+
+	generateContentConfig := &genai.GenerateContentConfig{
+		ModelSelectionConfig: modelSelectionConfig,
+	}
+
+	modelName := "gemini-2.5-flash"
+	contents := genai.Text("How does AI work?")
+
+	resp, err := client.Models.GenerateContent(ctx,
+		modelName,
+		contents,
+		generateContentConfig,
+	)
+	if err != nil {
+		return fmt.Errorf("failed to generate content: %w", err)
+	}
+
+	respText := resp.Text()
+
+	fmt.Fprintln(w, respText)
+	// Example response:
+	// That's a great question! Understanding how AI works can feel like ...
+	// ...
+	// **1. The Foundation: Data and Algorithms**
+	// ...
+
+	return nil
+}
+
+// [END googlegenaisdk_model_optimizer_textgen_with_txt]

genai/text_generation/textgen_thinking_with_txt.go

@@ -0,0 +1,62 @@
+// Copyright 2025 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 text_generation shows examples of generating text using the GenAI SDK.
+package text_generation
+
+// [START googlegenaisdk_thinking_textgen_with_txt]
+import (
+	"context"
+	"fmt"
+	"io"
+
+	"google.golang.org/genai"
+)
+
+// generateThinkingWithText shows how to generate thinking using a text prompt.
+func generateThinkingWithText(w io.Writer) error {
+	ctx := context.Background()
+
+	client, err := genai.NewClient(ctx, &genai.ClientConfig{
+		HTTPOptions: genai.HTTPOptions{APIVersion: "v1"},
+	})
+	if err != nil {
+		return fmt.Errorf("failed to create genai client: %w", err)
+	}
+
+	resp, err := client.Models.GenerateContent(ctx,
+		"gemini-2.5-flash",
+		genai.Text("solve x^2 + 4x + 4 = 0"),
+		nil,
+	)
+	if err != nil {
+		return fmt.Errorf("failed to generate content: %w", err)
+	}
+
+	respText := resp.Text()
+
+	fmt.Fprintln(w, respText)
+	// Example response:
+	// To solve the quadratic equation $x^2 + 4x + 4 = 0$, we can use a few methods:
+	//
+	// **Method 1: Factoring (Recognizing a Perfect Square Trinomial)**
+	// **1. The Foundation: Data and Algorithms**
+	//
+	// Notice that the left side of the equation is a perfect square trinomial.
+	// ...
+
+	return nil
+}
+
+// [END googlegenaisdk_thinking_textgen_with_txt]

genai/text_generation/textgen_with_chat_stream.go

@@ -0,0 +1,71 @@
+// Copyright 2025 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 text_generation shows examples of generating text using the GenAI SDK.
+package text_generation
+
+// [START googlegenaisdk_textgen_chat_stream_with_txt]
+import (
+	"context"
+	"fmt"
+	"io"
+
+	"google.golang.org/genai"
+)
+
+// generateChatStreamWithText shows how to generate chat stream using a text prompt.
+func generateChatStreamWithText(w io.Writer) error {
+	ctx := context.Background()
+
+	client, err := genai.NewClient(ctx, &genai.ClientConfig{
+		HTTPOptions: genai.HTTPOptions{APIVersion: "v1"},
+	})
+	if err != nil {
+		return fmt.Errorf("failed to create genai client: %w", err)
+	}
+
+	modelName := "gemini-2.5-flash"
+
+	chatSession, err := client.Chats.Create(ctx, modelName, nil, nil)
+	if err != nil {
+		return fmt.Errorf("failed to create genai chat session: %w", err)
+	}
+
+	var streamErr error
+	contents := genai.Part{Text: "Why is the sky blue?"}
+
+	stream := chatSession.SendMessageStream(ctx, contents)
+	stream(func(resp *genai.GenerateContentResponse, err error) bool {
+		if err != nil {
+			streamErr = err
+			return false
+		}
+		for _, cand := range resp.Candidates {
+			for _, part := range cand.Content.Parts {
+				fmt.Fprintln(w, part.Text)
+			}
+		}
+		return true
+	})
+
+	// Example response:
+	// The
+	// sky appears blue due to a phenomenon called **Rayleigh scattering**.
+	// Here's a breakdown:
+	// ...
+
+	return streamErr
+}
+
+// [END googlegenaisdk_textgen_chat_stream_with_txt]