chore: add new regen code (#1403)

autosynth is going away later this week so we need to migrate the
regen. This code will eventually be called by a kokoro nightly job.

internal/kokoro/discogen/go.mod

@@ -0,0 +1,16 @@
+module google.golang.org/api/internal/kokoro/discogen
+
+go 1.17
+
+require (
+	github.com/google/go-github/v42 v42.0.0
+	golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be
+)
+
+require (
+	github.com/golang/protobuf v1.3.2 // indirect
+	github.com/google/go-querystring v1.1.0 // indirect
+	golang.org/x/crypto v0.0.0-20210817164053-32db794688a5 // indirect
+	golang.org/x/net v0.0.0-20210226172049-e18ecbb05110 // indirect
+	google.golang.org/appengine v1.6.7 // indirect
+)

internal/kokoro/discogen/go.sum

@@ -0,0 +1,32 @@
+github.com/bradleyfalzon/ghinstallation/v2 v2.0.3/go.mod h1:tlgi+JWCXnKFx/Y4WtnDbZEINo31N5bcvnCoqieefmk=
+github.com/golang-jwt/jwt/v4 v4.0.0/go.mod h1:/xlHOz8bRuivTWchD4jCa+NbatV+wEUSzwAxVc6locg=
+github.com/golang/protobuf v1.3.1/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/golang/protobuf v1.3.2 h1:6nsPYzhq5kReh6QImI3k5qWzO4PEbvbIW2cwSfR/6xs=
+github.com/golang/protobuf v1.3.2/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/google/go-cmp v0.5.2/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/go-cmp v0.5.6 h1:BKbKCqvP6I+rmFHt06ZmyQtvB8xAkWdhFyr0ZUNZcxQ=
+github.com/google/go-cmp v0.5.6/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/go-github/v39 v39.0.0/go.mod h1:C1s8C5aCC9L+JXIYpJM5GYytdX52vC1bLvHEF1IhBrE=
+github.com/google/go-github/v42 v42.0.0 h1:YNT0FwjPrEysRkLIiKuEfSvBPCGKphW5aS5PxwaoLec=
+github.com/google/go-github/v42 v42.0.0/go.mod h1:jgg/jvyI0YlDOM1/ps6XYh04HNQ3vKf0CVko62/EhRg=
+github.com/google/go-querystring v1.1.0 h1:AnCroh3fv4ZBgVIf1Iwtovgjaw/GiKJo8M8yD/fhyJ8=
+github.com/google/go-querystring v1.1.0/go.mod h1:Kcdr2DB4koayq7X8pmAG4sNG59So17icRSOU623lUBU=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20210817164053-32db794688a5 h1:HWj/xjIHfjYU5nVXpTM0s39J9CbLn7Cc5a7IC5rwsMQ=
+golang.org/x/crypto v0.0.0-20210817164053-32db794688a5/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
+golang.org/x/net v0.0.0-20190603091049-60506f45cf65/go.mod h1:HSz+uSET+XFnRR8LxR5pz3Of3rY3CfYBVs4xY44aLks=
+golang.org/x/net v0.0.0-20210226172049-e18ecbb05110 h1:qWPm9rbaAMKs8Bq/9LRpbMqxWRVUAQwMI9fVrssnTfw=
+golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
+golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be h1:vEDujvNQGv4jgYKudGeI/+DAX4Jffq6hpD55MmoEvKs=
+golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
+golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
+golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+google.golang.org/appengine v1.6.7 h1:FZR1q0exgwxzPzp/aF+VccGrSfxfPpkBqjIIEq3ru6c=
+google.golang.org/appengine v1.6.7/go.mod h1:8WjMMxjGQR8xUklV/ARdw2HLXBOI7O7uCIDZVag1xfc=

internal/kokoro/discogen/main.go

@@ -0,0 +1,180 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"os"
+	"os/exec"
+	"os/user"
+	"path"
+	"path/filepath"
+	"strings"
+
+	"github.com/google/go-github/v42/github"
+	"golang.org/x/oauth2"
+)
+
+const (
+	branchName  = "discogen"
+	commitTitle = "feat(all): auto-regenerate discovery clients"
+	owner       = "googleapis"
+	repo        = "google-api-go-client"
+)
+
+func main() {
+	ctx := context.Background()
+
+	githubAccessToken := flag.String("github-access-token", os.Getenv("GITHUB_ACCESS_TOKEN"), "The token used to open pull requests. Required.")
+	githubUsername := flag.String("github-username", os.Getenv("GITHUB_USERNAME"), "The GitHub user name for the author. Required.")
+	githubName := flag.String("github-name", os.Getenv("GITHUB_NAME"), "The name of the author for git commits. Required.")
+	githubEmail := flag.String("github-email", os.Getenv("GITHUB_EMAIL"), "The email address of the author. Required.")
+	discoDir := flag.String("discovery-dir", os.Getenv("DISCOVERY_DIR"), "Directory where sources of googleapis/google-api-go-client resides. Required.")
+
+	flag.Parse()
+
+	if *githubAccessToken == "" || *githubUsername == "" || *githubName == "" || *githubEmail == "" || *discoDir == "" {
+		log.Fatal("all required flags not set")
+	}
+
+	if err := setGitCreds(*githubName, *githubEmail, *githubUsername, *githubAccessToken); err != nil {
+		log.Fatalf("unable to set git credentials: %v", err)
+	}
+
+	if prIsOpen, err := isPROpen(ctx, *githubAccessToken, *githubUsername); err != nil || prIsOpen {
+		if err != nil {
+			log.Fatalf("unable to check PR status: %v", err)
+		}
+		log.Println("a regen PR is already open, nothing to do here")
+		os.Exit(0)
+	}
+
+	if err := generate(*discoDir); err != nil {
+		log.Fatalf("unable to generate discovery clients: %v", err)
+	}
+
+	if hasChanges, err := hasChanges(*discoDir); err != nil || !hasChanges {
+		if err != nil {
+			log.Fatalf("unable to check git status: %v", err)
+		}
+		log.Println("no local changes, exiting")
+		os.Exit(0)
+	}
+
+	if err := makePR(ctx, *githubAccessToken, *discoDir); err != nil {
+		log.Fatalf("unable to make regen PR: %v", err)
+	}
+}
+
+// setGitCreds configures credentials for GitHub.
+func setGitCreds(githubName, githubEmail, githubUsername, accessToken string) error {
+	u, err := user.Current()
+	if err != nil {
+		return err
+	}
+	gitCredentials := []byte(fmt.Sprintf("https://%s:%s@github.com", githubUsername, accessToken))
+	if err := ioutil.WriteFile(path.Join(u.HomeDir, ".git-credentials"), gitCredentials, 0644); err != nil {
+		return err
+	}
+	c := exec.Command("git", "config", "--global", "user.name", githubName)
+	if err := c.Run(); err != nil {
+		return err
+	}
+
+	c = exec.Command("git", "config", "--global", "user.email", githubEmail)
+	return c.Run()
+}
+
+// isPROpen checks if a regen PR is already open.
+func isPROpen(ctx context.Context, accessToken, username string) (bool, error) {
+	ts := oauth2.StaticTokenSource(
+		&oauth2.Token{AccessToken: accessToken},
+	)
+	tc := oauth2.NewClient(ctx, ts)
+	githubClient := github.NewClient(tc)
+	opt := &github.PullRequestListOptions{
+		ListOptions: github.ListOptions{PerPage: 50},
+		State:       "open",
+	}
+	prs, _, err := githubClient.PullRequests.List(ctx, owner, repo, opt)
+	if err != nil {
+		return false, err
+	}
+	for _, pr := range prs {
+		if !strings.Contains(pr.GetTitle(), "auto-regenerate") {
+			continue
+		}
+		if pr.GetUser().GetLogin() != username {
+			continue
+		}
+		return true, nil
+	}
+	return false, nil
+}
+
+// generate regenerates the whole project.
+func generate(dir string) error {
+	fp := filepath.Join(dir, "google-api-go-generator")
+	cmd := exec.Command("make", "all")
+	cmd.Dir = fp
+	cmd.Stderr = os.Stderr
+	cmd.Stdout = os.Stdout
+	return cmd.Run()
+}
+
+// hasChanges reports if any files have been updated.
+func hasChanges(dir string) (bool, error) {
+	c := exec.Command("git", "status", "--short")
+	c.Dir = dir
+	b, err := c.Output()
+	return len(b) > 0, err
+}
+
+// makePR commits local changes and makes a regen PR.
+func makePR(ctx context.Context, accessToken, dir string) error {
+	c := exec.Command("/bin/bash", "-c", `
+	set -ex
+	
+	git config credential.helper store
+	
+	git branch -D $BRANCH_NAME || true
+	git push -d origin $BRANCH_NAME || true
+	
+	git add -A
+	git checkout -b $BRANCH_NAME
+	git commit -m "$COMMIT_TITLE"
+	git push origin $BRANCH_NAME
+	`)
+	c.Env = []string{
+		fmt.Sprintf("COMMIT_TITLE=%s", commitTitle),
+		fmt.Sprintf("BRANCH_NAME=%s", branchName),
+	}
+	c.Dir = dir
+	if err := c.Run(); err != nil {
+		return err
+	}
+
+	ts := oauth2.StaticTokenSource(
+		&oauth2.Token{AccessToken: accessToken},
+	)
+	tc := oauth2.NewClient(ctx, ts)
+	githubClient := github.NewClient(tc)
+	head := owner + ":" + branchName
+	base := "main"
+	t := commitTitle
+	_, _, err := githubClient.PullRequests.Create(ctx, owner, repo, &github.NewPullRequest{
+		Title: &t,
+		Head:  &head,
+		Base:  &base,
+	})
+	if err != nil {
+		return err
+	}
+	return nil
+}