AWS Lambdaでリポジトリの内容を書き換えるサンプル

handler.go

package main

import (
	"encoding/base64"
	"encoding/json"
	"fmt"
	"io/ioutil"
	"os"
	"time"

	"gopkg.in/src-d/go-billy.v4"

	"gopkg.in/src-d/go-git.v4/plumbing/object"
	"gopkg.in/src-d/go-git.v4/storage/memory"

	"github.com/aws/aws-lambda-go/events"
	"github.com/aws/aws-lambda-go/lambda"
	jsonpointer "github.com/mattn/go-jsonpointer"
	"gopkg.in/src-d/go-billy.v4/memfs"
	"gopkg.in/src-d/go-git.v4"
	"gopkg.in/src-d/go-git.v4/config"
	"gopkg.in/src-d/go-git.v4/plumbing"
)

var token = os.Getenv("GITHUB_ACCESS_TOKEN")
var userID = "<your-github-id>"

type Request struct {
	Version string `json:"version"`
}

func decodeBody(body string) (*Request, error) {
	var ur Request
	b, err := base64.StdEncoding.DecodeString(body)
	if err != nil {
		return nil, err
	}

	err = json.Unmarshal(b, &ur)
	if err != nil {
		return nil, err
	}
	return &ur, nil
}

func rewriteVersion(fs billy.Filesystem, version string) (err error) {
	file, err := fs.Open(".version")
	if err != nil {
		return
	}
	b, err := ioutil.ReadAll(file)
	if err != nil {
		return
	}
	err = file.Close()
	if err != nil {
		return
	}

	var obj interface{}
	json.Unmarshal(b, &obj)
	jsonpointer.Set(obj, "/version", version)
	rb, err := json.MarshalIndent(obj, "", "    ")

	if err != nil {
		return
	}
	err = fs.Remove(".version")
	if err != nil {
		return
	}

	file, err = fs.OpenFile(".version", os.O_RDWR|os.O_CREATE, 0666)
	if err != nil {
		return
	}

	_, err = file.Write(rb)
	if err != nil {
		return
	}

	_, err = file.Write([]byte("\n"))
	return
}

func Commit(req events.APIGatewayProxyRequest) (events.APIGatewayProxyResponse, error) {
	fmt.Printf("request body:%s \n", req.Body)
	f := memfs.New()
	repo, err := git.Clone(memory.NewStorage(), f, &git.CloneOptions{
		URL:           "https://" + userID + ":" + token + "@github.com/<your-user-id>/<your-repoistory>.git",
		ReferenceName: plumbing.ReferenceName("refs/heads/develop"),
	})

	ur, err := decodeBody(req.Body)
	if err != nil {
		return events.APIGatewayProxyResponse{
			StatusCode: 400,
			Body:       err.Error(),
		}, nil
	}

	if ur.Version == "" {
		return events.APIGatewayProxyResponse{
			StatusCode: 400,
			Body:       "version is empty.",
		}, nil
	}

	w, err := repo.Worktree()
	err = w.Checkout(&git.CheckoutOptions{
		Create: true,
		Branch: "feature/test-update",
	})

	if err != nil {
		return events.APIGatewayProxyResponse{
			StatusCode: 500,
			Body:       err.Error(),
		}, nil
	}

	// ファイルを書き換える
	err = rewriteVersion(f, ur.Version)
	if err != nil {
		return events.APIGatewayProxyResponse{
			StatusCode: 500,
			Body:       err.Error(),
		}, nil
	}

	// Commitする
	_, err = w.Add(".version")
	ref := plumbing.ReferenceName("feature/test-update")
	if err == nil {
		hash, _ := w.Commit("test", &git.CommitOptions{
			Author: &object.Signature{
				Name:  "<your-github-id>",
				Email: "<your-mail-address>",
				When:  time.Now(),
			},
		})
		repo.Storer.SetReference(plumbing.NewReferenceFromStrings("feature/test-update", hash.String()))
	}

	if err != nil {
		return events.APIGatewayProxyResponse{
			StatusCode: 500,
			Body:       err.Error(),
		}, nil
	}

	// Pushする
	remote, err := repo.Remote("origin")
	if err == nil {
		err = remote.Push(&git.PushOptions{
			Progress: os.Stdout,
			RefSpecs: []config.RefSpec{
				config.RefSpec(ref + ":" + plumbing.ReferenceName("refs/heads/feature/test-update")),
			},
		})
	}

	if err != nil {
		return events.APIGatewayProxyResponse{
			StatusCode: 500,
			Body:       err.Error(),
		}, nil
	}

	return events.APIGatewayProxyResponse{
		StatusCode: 200,
		Body:       "updated version",
	}, nil
}

func main() {
	lambda.Start(Commit)
}