cmd/gopherbot: replace maintner with GitHub API v4 in ping-early-issues

Do this here first to make the diff easier to see.
The next CL in stack moves it to relui.

Notably the GraphQL implementation here is missing the "avoid duplicate
comments" safety net implemented in maintner-powered addGitHubComment.
With maintner, it costs no API calls to check all comments in a GitHub
issue for a past comment. When using the GitHub API, this unfortunately
costs more API quota and needs to be implemented explicitly, adding to
the verbosity of the implementation.

For golang/go#58856.

Change-Id: I2757697e561cb00d041f65ba846d902c0de35e22
Reviewed-on: https://go-review.googlesource.com/c/build/+/473159
Reviewed-by: Heschi Kreinick <[email protected]>
Reviewed-by: Dmitri Shuralyov <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>
Auto-Submit: Dmitri Shuralyov <[email protected]>
Run-TryBot: Dmitri Shuralyov <[email protected]>

Author: dmitshur

cmd/gopherbot/gopherbot.go

@@ -30,6 +30,7 @@ import (
 
 	"cloud.google.com/go/compute/metadata"
 	"github.com/google/go-github/v48/github"
+	"github.com/shurcooL/githubv4"
 	"go4.org/strutil"
 	"golang.org/x/build/devapp/owners"
 	"golang.org/x/build/gerrit"
@@ -47,7 +48,7 @@ import (
 var (
 	dryRun          = flag.Bool("dry-run", false, "just report what would've been done, without changing anything")
 	daemon          = flag.Bool("daemon", false, "run in daemon mode")
-	githubTokenFile = flag.String("github-token-file", filepath.Join(os.Getenv("HOME"), "keys", "github-gobot"), `File to load Github token from. File should be of form <username>:<token>`)
+	githubTokenFile = flag.String("github-token-file", filepath.Join(os.Getenv("HOME"), "keys", "github-gobot"), `File to load GitHub token from. File should be of form <username>:<token>`)
 	// go here: https://go-review.googlesource.com/settings#HTTPCredentials
 	// click "Obtain Password"
 	// The next page will have a .gitcookies file - look for the part that has
@@ -112,7 +113,7 @@ type milestone struct {
 	Name   string
 }
 
-func getGithubToken(ctx context.Context, sc *secret.Client) (string, error) {
+func getGitHubToken(ctx context.Context, sc *secret.Client) (string, error) {
 	if metadata.OnGCE() && sc != nil {
 		ctxSc, cancel := context.WithTimeout(ctx, 10*time.Second)
 		defer cancel()
@@ -163,17 +164,18 @@ func getGerritAuth(ctx context.Context, sc *secret.Client) (username string, pas
 	return f[0], f[1], nil
 }
 
-func getGithubClient(ctx context.Context, sc *secret.Client) (*github.Client, error) {
-	token, err := getGithubToken(ctx, sc)
+func getGitHubClients(ctx context.Context, sc *secret.Client) (*github.Client, *githubv4.Client, error) {
+	token, err := getGitHubToken(ctx, sc)
 	if err != nil {
 		if *dryRun {
-			return github.NewClient(http.DefaultClient), nil
+			// Note: GitHub API v4 requires requests to be authenticated, which isn't implemented here.
+			return github.NewClient(http.DefaultClient), githubv4.NewClient(http.DefaultClient), nil
 		}
-		return nil, err
+		return nil, nil, err
 	}
 	ts := oauth2.StaticTokenSource(&oauth2.Token{AccessToken: token})
 	tc := oauth2.NewClient(context.Background(), ts)
-	return github.NewClient(tc), nil
+	return github.NewClient(tc), githubv4.NewClient(tc), nil
 }
 
 func getGerritClient(ctx context.Context, sc *secret.Client) (*gerrit.Client, error) {
@@ -230,7 +232,7 @@ func main() {
 	}
 	ctx := context.Background()
 
-	ghc, err := getGithubClient(ctx, sc)
+	ghV3, ghV4, err := getGitHubClients(ctx, sc)
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -246,10 +248,11 @@ func main() {
 	var goRepo = maintner.GitHubRepoID{Owner: "golang", Repo: "go"}
 	var vscode = maintner.GitHubRepoID{Owner: "golang", Repo: "vscode-go"}
 	bot := &gopherbot{
-		ghc:    ghc,
+		ghc:    ghV3,
+		ghV4:   ghV4,
 		gerrit: gerrit,
 		mc:     mc,
-		is:     ghc.Issues,
+		is:     ghV3.Issues,
 		deletedChanges: map[gerritChange]bool{
 			{"crypto", 35958}:  true,
 			{"scratch", 71730}: true,
@@ -408,6 +411,7 @@ func main() {
 
 type gopherbot struct {
 	ghc    *github.Client
+	ghV4   *githubv4.Client
 	gerrit *gerrit.Client
 	mc     apipb.MaintnerServiceClient
 	corpus *maintner.Corpus
@@ -949,28 +953,97 @@ func (b *gopherbot) pingEarlyIssues(ctx context.Context) error {
 	// for general Go 1.x development. Update the openTreeURLs map appropriately when
 	// running this task.
 	openTreeURLs := map[string]string{
-		"1.21": "https://groups.google.com/g/golang-dev/c/09IwUs7cxXA/m/_JHOzNjXBAAJ",
+		"1.22": "https://groups.google.com/g/golang-dev/c/FNPk2joOsXs/m/roCc_a4fBAAJ",
 	}
 	if url, ok := openTreeURLs[nextMajor]; !ok {
 		return fmt.Errorf("openTreeURLs[%q] is missing a value, please fill it in", nextMajor)
 	} else if !strings.HasPrefix(url, "https://groups.google.com/g/golang-dev/c/") {
 		return fmt.Errorf("openTreeURLs[%q] is %q, which doesn't begin with the usual prefix, so please double-check that the URL is correct", nextMajor, url)
 	}
+	var milestoneNumber int // TODO: Determine the milestone number dynamically.
+	if nextMajor == "1.22" {
+		milestoneNumber = 298
+	} else {
+		return fmt.Errorf("major to milestone number mapping is not implemented")
+	}
 
-	return b.foreachIssue(b.gorepo, open, func(gi *maintner.GitHubIssue) error {
-		if !gi.HasLabelID(earlyInCycleID) || gi.Milestone.Title != "Go"+nextMajor {
-			return nil
+	// Find all open early-in-cycle issues in the current major release milestone.
+	type issue struct {
+		ID     githubv4.ID
+		Number int
+		Title  string
+
+		TimelineItems struct {
+			Nodes []struct {
+				IssueComment struct {
+					Author struct{ Login string }
+					Body   string
+				} `graphql:"...on IssueComment"`
+			}
+		} `graphql:"timelineItems(since: $avoidDupSince, itemTypes: ISSUE_COMMENT, last: 100)"`
+	}
+	var earlyIssues []issue
+	variables := map[string]interface{}{
+		"avoidDupSince":   githubv4.DateTime{Time: time.Now().Add(-30 * 24 * time.Hour)},
+		"milestoneNumber": githubv4.String(fmt.Sprint(milestoneNumber)), // For some reason GitHub API v4 uses string type for milestone numbers.
+		"issueCursor":     (*githubv4.String)(nil),
+	}
+	for {
+		var q struct {
+			Repository struct {
+				Issues struct {
+					Nodes    []issue
+					PageInfo struct {
+						EndCursor   githubv4.String
+						HasNextPage bool
+					}
+				} `graphql:"issues(first: 100, after: $issueCursor, filterBy: {states: OPEN, labels: \"early-in-cycle\", milestoneNumber: $milestoneNumber}, orderBy: {field: CREATED_AT, direction: ASC})"`
+			} `graphql:"repository(owner: \"golang\", name: \"go\")"`
 		}
+		err := b.ghV4.Query(ctx, &q, variables)
+		if err != nil {
+			return err
+		}
+		earlyIssues = append(earlyIssues, q.Repository.Issues.Nodes...)
+		if !q.Repository.Issues.PageInfo.HasNextPage {
+			break
+		}
+		variables["issueCursor"] = githubv4.NewString(q.Repository.Issues.PageInfo.EndCursor)
+	}
+
+	// Ping them.
+EarlyIssuesLoop:
+	for _, i := range earlyIssues {
+		for _, n := range i.TimelineItems.Nodes {
+			if n.IssueComment.Author.Login == "gopherbot" && strings.Contains(n.IssueComment.Body, "friendly reminder") {
+				log.Printf("skipping early-in-cycle issue %d, it was already pinged", i.Number)
+				continue EarlyIssuesLoop
+			}
+		}
+
+		// Post a comment.
 		if *dryRun {
-			log.Printf("[dry run] would ping early-in-cycle issue %d", gi.Number)
-			return nil
+			log.Printf("[dry run] would ping early-in-cycle issue\n\t#%d %s", i.Number, i.Title)
+			continue
 		}
-		log.Printf("pinging early-in-cycle issue %d", gi.Number)
+		log.Printf("pinging early-in-cycle issue %d (%.32s…)", i.Number, i.Title)
 		time.Sleep(3 * time.Second) // Take a moment between pinging issues, since a human will be running this task manually.
-		msg := fmt.Sprintf("This issue is currently labeled as early-in-cycle for Go %s.\n"+
-			"That [time is now](%s), so a friendly reminder to look at it again.", nextMajor, openTreeURLs[nextMajor])
-		return b.addGitHubComment(ctx, b.gorepo, gi.Number, msg)
-	})
+		var m struct {
+			AddComment struct {
+				ClientMutationID string // GraphQL doesn't permit empty mutations.
+			} `graphql:"addComment(input: $input)"`
+		}
+		err := b.ghV4.Mutate(ctx, &m, githubv4.AddCommentInput{
+			SubjectID: i.ID,
+			Body: githubv4.String(fmt.Sprintf("This issue is currently labeled as early-in-cycle for Go %s.\n"+
+				"That [time is now](%s), so a friendly reminder to look at it again.", nextMajor, openTreeURLs[nextMajor])),
+		}, nil)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
 }
 
 // freezeOldIssues locks any issue that's old and closed.