[tools] Add a new tool to auto-submit changes

The change must be authored by the user and requires the following labels:
* Code-Review+2
* Auto-Submit+2
* Kokoro+2

And must not have failed CQ with the latest patchset.

Change-Id: Ic7b76a69a8dd134c11cb1c2a9964ab11d9fdde34
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/133468
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Ben Clayton <bclayton@google.com>
Reviewed-by: Dan Sinclair <dsinclair@chromium.org>
Auto-Submit: Ben Clayton <bclayton@google.com>

tools/src/cmd/auto-submit/main.go

@@ -0,0 +1,216 @@
+// Copyright 2023 The Tint Authors.
+//
+// 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.
+
+// auto-submit applies the 'Commit-Queue+2' label to Gerrit changes authored by the user
+// that are ready to be submitted
+package main
+
+import (
+	"flag"
+	"fmt"
+	"log"
+	"os"
+	"os/exec"
+	"strings"
+	"time"
+
+	"dawn.googlesource.com/dawn/tools/src/dawn"
+	"dawn.googlesource.com/dawn/tools/src/gerrit"
+	"dawn.googlesource.com/dawn/tools/src/git"
+)
+
+const (
+	toolName       = "auto-submit"
+	cqEmailAccount = "dawn-scoped@luci-project-accounts.iam.gserviceaccount.com"
+)
+
+var (
+	// See https://dawn-review.googlesource.com/new-password for obtaining
+	// username and password for gerrit.
+	gerritUser  = flag.String("gerrit-user", "", "gerrit authentication username")
+	gerritPass  = flag.String("gerrit-pass", "", "gerrit authentication password")
+	repoFlag    = flag.String("repo", "dawn", "the repo")
+	userFlag    = flag.String("user", defaultUser(), "user name / email")
+	verboseFlag = flag.Bool("v", false, "verbose mode")
+	dryrunFlag  = flag.Bool("dry", false, "dry mode. Don't apply any labels")
+)
+
+func defaultUser() string {
+	if gitExe, err := exec.LookPath("git"); err == nil {
+		if g, err := git.New(gitExe); err == nil {
+			if cwd, err := os.Getwd(); err == nil {
+				if r, err := g.Open(cwd); err == nil {
+					if cfg, err := r.Config(nil); err == nil {
+						return cfg["user.email"]
+					}
+				}
+			}
+		}
+	}
+	return ""
+}
+
+func main() {
+	flag.Usage = func() {
+		out := flag.CommandLine.Output()
+		fmt.Fprintf(out,
+			`%v applies the 'Commit-Queue+2' label to Gerrit changes authored by the user that are ready to be submitted.
+
+The tool monitors Gerrit changes authored by the user, looking for changes that have the labels
+'Kokoro+1', 'Auto-Submit +1' and 'Code-Review +2' and applies the 'Commit-Queue +2' label.
+`, toolName)
+		fmt.Fprintf(out, "\n")
+		flag.PrintDefaults()
+	}
+	flag.Parse()
+	if err := run(); err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+}
+
+func run() error {
+	user := *userFlag
+	if user == "" {
+		return fmt.Errorf("Missing required 'user' flag")
+	}
+
+	g, err := gerrit.New(dawn.GerritURL, gerrit.Credentials{
+		Username: *gerritUser, Password: *gerritPass,
+	})
+	if err != nil {
+		return err
+	}
+
+	app := app{Gerrit: g, user: user}
+
+	log.Println("Monitoring for changes ready to be submitted...")
+
+	for {
+		err := app.submitReadyChanges()
+		if err != nil {
+			fmt.Println("error: ", err)
+			time.Sleep(time.Minute * 10)
+		}
+		time.Sleep(time.Minute * 5)
+	}
+}
+
+type app struct {
+	*gerrit.Gerrit
+	user string // User account of changes to submit
+}
+
+func (a *app) submitReadyChanges() error {
+	if *verboseFlag {
+		log.Println("Scanning for changes to submit...")
+	}
+
+	changes, _, err := a.QueryChangesWith(
+		gerrit.QueryExtraData{
+			Labels:           true,
+			Messages:         true,
+			CurrentRevision:  true,
+			DetailedAccounts: true,
+		},
+		"status:open",
+		"author:"+a.user,
+		"-is:wip",
+		"label:auto-submit",
+		"label:kokoro",
+		"repo:"+*repoFlag)
+	if err != nil {
+		return fmt.Errorf("failed to Query changes: %w", err)
+	}
+
+	for _, change := range changes {
+		// Returns true if the change has the label with the given value
+		hasLabel := func(name string, value int) bool {
+			if label, ok := change.Labels[name]; ok {
+				for _, vote := range label.All {
+					if vote.Value == value {
+						return true
+					}
+				}
+			}
+			return false
+		}
+
+		isReadyToSubmit := true &&
+			hasLabel("Kokoro", 1) &&
+			hasLabel("Auto-Submit", 1) &&
+			hasLabel("Code-Review", 2) &&
+			!hasLabel("Code-Review", -1) &&
+			!hasLabel("Code-Review", -2)
+		if !isReadyToSubmit {
+			// Change does not have all the required labels to submit
+			continue
+		}
+
+		if hasLabel("Commit-Queue", 2) {
+			// Change already in the process of submitting
+			continue
+		}
+
+		switch parseCQStatus(change) {
+		case cqUnknown, cqPassed:
+			if *dryrunFlag {
+				log.Printf("Would submit %v: %v... (--dry)\n", change.ChangeID, change.Subject)
+				continue
+			}
+
+			log.Printf("Submitting %v: %v...\n", change.ChangeID, change.Subject)
+			err := a.AddLabel(change.ChangeID, change.CurrentRevision, "Auto submitting change", "Commit-Queue", 2)
+			if err != nil {
+				return fmt.Errorf("failed to set Commit-Queue label: %w", err)
+			}
+
+		case cqFailed:
+			if *verboseFlag {
+				log.Printf("Change failed CQ: %v: %v...\n", change.ChangeID, change.Subject)
+			}
+		}
+	}
+
+	return nil
+}
+
+// CQ result status enumerator
+type cqStatus int
+
+// CQ result status enumerator values
+const (
+	cqUnknown cqStatus = iota
+	cqPassed
+	cqFailed
+)
+
+// Attempt to parse the CQ result from the latest patchset's messages from CQ
+func parseCQStatus(change gerrit.ChangeInfo) cqStatus {
+	currentPatchset := change.Revisions[change.CurrentRevision].Number
+	for _, msg := range change.Messages {
+		if msg.RevisionNumber != currentPatchset {
+			continue
+		}
+		if msg.Author.Email == cqEmailAccount {
+			if strings.Contains(msg.Message, "This CL has passed the run") {
+				return cqPassed
+			}
+			if strings.Contains(msg.Message, "This CL has failed the run") {
+				return cqFailed
+			}
+		}
+	}
+	return cqUnknown
+}

tools/src/gerrit/gerrit.go

@@ -122,15 +122,39 @@ func New(url string, cred Credentials) (*Gerrit, error) {
 	return &Gerrit{client, cred.Username != ""}, nil
 }
 
+// QueryExtraData holds extra data to query for with QueryChangesWith()
+type QueryExtraData struct {
+	Labels           bool
+	Messages         bool
+	CurrentRevision  bool
+	DetailedAccounts bool
+}
+
 // QueryChanges returns the changes that match the given query strings.
 // See: https://gerrit-review.googlesource.com/Documentation/user-search.html#search-operators
-func (g *Gerrit) QueryChanges(querys ...string) (changes []gerrit.ChangeInfo, query string, err error) {
+func (g *Gerrit) QueryChangesWith(extras QueryExtraData, queries ...string) (changes []gerrit.ChangeInfo, query string, err error) {
 	changes = []gerrit.ChangeInfo{}
-	query = strings.Join(querys, "+")
+	query = strings.Join(queries, "+")
+
+	changeOpts := gerrit.ChangeOptions{}
+	if extras.Labels {
+		changeOpts.AdditionalFields = append(changeOpts.AdditionalFields, "LABELS")
+	}
+	if extras.Messages {
+		changeOpts.AdditionalFields = append(changeOpts.AdditionalFields, "MESSAGES")
+	}
+	if extras.CurrentRevision {
+		changeOpts.AdditionalFields = append(changeOpts.AdditionalFields, "CURRENT_REVISION")
+	}
+	if extras.DetailedAccounts {
+		changeOpts.AdditionalFields = append(changeOpts.AdditionalFields, "DETAILED_ACCOUNTS")
+	}
+
 	for {
 		batch, _, err := g.client.Changes.QueryChanges(&gerrit.QueryChangeOptions{
-			QueryOptions: gerrit.QueryOptions{Query: []string{query}},
+			QueryOptions:  gerrit.QueryOptions{Query: []string{query}},
-			Skip:         len(changes),
+			Skip:          len(changes),
+			ChangeOptions: changeOpts,
 		})
 		if err != nil {
 			return nil, "", g.maybeWrapError(err)
@@ -144,6 +168,23 @@ func (g *Gerrit) QueryChanges(querys ...string) (changes []gerrit.ChangeInfo, qu
 	return changes, query, nil
 }
 
+// QueryChanges returns the changes that match the given query strings.
+// See: https://gerrit-review.googlesource.com/Documentation/user-search.html#search-operators
+func (g *Gerrit) QueryChanges(queries ...string) (changes []gerrit.ChangeInfo, query string, err error) {
+	return g.QueryChangesWith(QueryExtraData{}, queries...)
+}
+
+func (g *Gerrit) AddLabel(changeID, revisionID, message, label string, value int) error {
+	_, _, err := g.client.Changes.SetReview(changeID, revisionID, &gerrit.ReviewInput{
+		Message: message,
+		Labels:  map[string]string{label: fmt.Sprint(value)},
+	})
+	if err != nil {
+		return g.maybeWrapError(err)
+	}
+	return nil
+}
+
 // Abandon abandons the change with the given changeID.
 func (g *Gerrit) Abandon(changeID string) error {
 	_, _, err := g.client.Changes.AbandonChange(changeID, &gerrit.AbandonInput{})