// 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
//
// http://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 main
import (
"context"
"fmt"
"log"
"net/http"
"github.com/firebase/genkit/go/ai"
"github.com/firebase/genkit/go/genkit"
"github.com/firebase/genkit/go/plugins/googlegenai"
"github.com/firebase/genkit/go/plugins/server"
"google.golang.org/genai"
)
func main() {
ctx := context.Background()
// Initialize Genkit with the Google AI plugin. When you pass nil for the
// Config parameter, the Google AI plugin will get the API key from the
// GEMINI_API_KEY or GOOGLE_API_KEY environment variable, which is the recommended
// practice.
g := genkit.Init(ctx, genkit.WithPlugins(&googlegenai.GoogleAI{}))
// Define a non-streaming flow that generates jokes about a given topic.
genkit.DefineFlow(g, "jokesFlow", func(ctx context.Context, input string) (string, error) {
if input == "" {
input = "airplane food"
}
return genkit.GenerateText(ctx, g,
ai.WithModel(googlegenai.ModelRef("gemini-2.5-flash", &genai.GenerateContentConfig{
ThinkingConfig: &genai.ThinkingConfig{
ThinkingBudget: genai.Ptr[int32](0),
},
})),
ai.WithPrompt("Share a joke about %s.", input),
)
},
)
// Define a streaming flow that generates jokes about a given topic with passthrough streaming.
genkit.DefineStreamingFlow(g, "streamingJokesFlow",
func(ctx context.Context, input string, sendChunk ai.ModelStreamCallback) (string, error) {
if input == "" {
input = "airplane food"
}
resp, err := genkit.Generate(ctx, g,
ai.WithModel(googlegenai.ModelRef("gemini-2.5-flash", &genai.GenerateContentConfig{
ThinkingConfig: &genai.ThinkingConfig{
ThinkingBudget: genai.Ptr[int32](0),
},
})),
ai.WithPrompt("Share a joke about %s.", input),
ai.WithStreaming(sendChunk),
)
if err != nil {
return "", fmt.Errorf("could not generate joke: %w", err)
}
return resp.Text(), nil
},
)
// Optionally, start a web server to make the flow callable via HTTP.
mux := http.NewServeMux()
for _, a := range genkit.ListFlows(g) {
mux.HandleFunc("POST /"+a.Name(), genkit.Handler(a))
}
log.Fatal(server.Start(ctx, "127.0.0.1:8080", mux))
}
