Cloudbuildとgoのginを使用してCloudRunとcloudFunctions(gen2)へデプロイする

ディレクトリ構造

./
├─/cmd
│ └── main.go
├─/handlers
│ └── handlers.go
├── Dockerfile
├── go.mod
├── go.sum
├── cloudbuild.yaml
└── router.go

goのソース

main.go

package main

import (
	"context"
	"log"

	router "github.com/yourname/gin"

	"github.com/GoogleCloudPlatform/functions-framework-go/funcframework"
)
func main() {

	ctx := context.Background()

	gin := router.GinHandler

	// 実行する関数の登録
	if err := funcframework.RegisterHTTPFunctionContext(ctx, "/", gin); err != nil {
		log.Fatalf("funcframework.RegisterHTTPFunctionContext: %v\n", err)
	}

	port := "8080"
	if err := funcframework.Start(port); err != nil {
		log.Fatalf("funcframework.Start: %v\n", err)
	}
}

• ginから拝借した

handlers.go

package handlers

import (
	"net/http"

	"github.com/gin-gonic/gin"
)

type album struct {
	ID     string  `json:"id"`
	Title  string  `json:"title"`
	Artist string  `json:"artist"`
	Price  float64 `json:"price"`
}

var albums = []album{
	{ID: "1", Title: "Blue Train", Artist: "John Coltrane", Price: 56.99},
	{ID: "2", Title: "Jeru", Artist: "Gerry Mulligan", Price: 17.99},
	{ID: "3", Title: "Sarah Vaughan", Artist: "Sarah Vaughan", Price: 39.99},
}

func GetAlbums(c *gin.Context) {
	c.JSON(http.StatusOK, albums)
}

func PostAlbums(c *gin.Context) {
	var newAlbum album
	if err := c.BindJSON(&newAlbum); err != nil {
		return
	}
	albums = append(albums, newAlbum)
	c.JSON(http.StatusCreated, newAlbum)
}

router.go

import (
	"net/http"

	"github.com/yourname/gin/handlers"
	"github.com/gin-gonic/gin"
)

func GinHandler(w http.ResponseWriter, r *http.Request) {
	gin.SetMode(gin.ReleaseMode)
	engine := gin.Default()

	engine.GET("/hello", func(c *gin.Context) {
		c.JSON(http.StatusOK, gin.H{
			"message": "hello world",
		})
	})
	engine.GET("/albums", handlers.GetAlbums)
	engine.ServeHTTP(w, r)
}

Dockefile

FROM golang:1.22-alpine AS builder
WORKDIR /app
COPY . .
RUN go build -o main ./cmd/main.go

FROM alpine:latest
WORKDIR /app
COPY --from=builder /app/main .
CMD ["./main"]

Cloudbuild.yaml

steps:
# Cloud Run用のビルドとデプロイ
- name: 'gcr.io/cloud-builders/docker'
  args: [ 'build', '-t', '${region}-docker.pkg.dev/${your-project-id}/${your-artifact-registry-reponame}/${image-name}:latest', '.' ]
- name: 'gcr.io/cloud-builders/docker'
  args: ['push', '${region}-docker.pkg.dev/${your-project-id}/${your-artifact-registry-reponame}/${image-name}:latest']
- name: 'gcr.io/google.com/cloudsdktool/cloud-sdk'
  entrypoint: gcloud
  args: ['run', 'deploy', '${CloudRun-name}', '--image', '${region}-docker.pkg.dev/${your-project-id}/${your-artifact-registry-reponame}/${image-name}:latest', '--region', '${region}', '--platform', 'managed', '--allow-unauthenticated']

# Cloud Functions用のデプロイ
- name: 'gcr.io/google.com/cloudsdktool/cloud-sdk'
  entrypoint: gcloud
  args: ['functions', 'deploy', '${CloudFunctions-name}','--gen2', '--runtime', 'go122', '--trigger-http', '--entry-point', 'GinHandler', '--region', 'asia-northeast1','--source','.','--allow-unauthenticated']

CloudFunctionsの注意点

deployしたい関数（今回だとrouter.goのfun）とgo.modの階層が違うとエラーになります