Automatically copy changelog message to the backport or put no-change…

…log label

bot/internal/bot/backport.go

@@ -30,9 +30,10 @@ import (
 	"strings"
 	"text/template"
 
-	"github.com/gravitational/shared-workflows/bot/internal/github"
-
 	"github.com/gravitational/trace"
+	"golang.org/x/exp/slices"
+
+	"github.com/gravitational/shared-workflows/bot/internal/github"
 )
 
 // Backport will create backport Pull Requests (if requested) when a Pull
@@ -79,6 +80,11 @@ func (b *Bot) Backport(ctx context.Context) error {
 
 	var rows []row
 
+	g := git
+	if b.c.Git != nil {
+		g = b.c.Git
+	}
+
 	// Loop over all requested backport branches and create backport branch and
 	// GitHub Pull Request.
 	for _, base := range branches {
@@ -92,7 +98,7 @@ func (b *Bot) Backport(ctx context.Context) error {
 			base,
 			pull,
 			head,
-			git,
+			g,
 		)
 		if err != nil {
 			log.Printf("Failed to create backport branch:\n%v\n", trace.DebugReport(err))
@@ -104,6 +110,16 @@ func (b *Bot) Backport(ctx context.Context) error {
 			continue
 		}
 
+		labels := []string{NoChangelogLabel}
+		bodyText := fmt.Sprintf("Backport #%v to %v", b.c.Environment.Number, base)
+		if entries := b.getChangelogEntries(pull.UnsafeBody); len(entries) > 0 && !slices.Contains(pull.UnsafeLabels, NoChangelogLabel) {
+			bodyText += "\n\n"
+			labels = labels[:0]
+			for _, entry := range entries {
+				bodyText += fmt.Sprintf("%s%s\n", ChangelogPrefix, entry)
+			}
+		}
+
 		rows = append(rows, row{
 			Branch: base,
 			Failed: false,
@@ -117,7 +133,8 @@ func (b *Bot) Backport(ctx context.Context) error {
 				RawQuery: url.Values{
 					"expand": []string{"1"},
 					"title":  []string{fmt.Sprintf("[%v] %v", strings.Trim(base, "branch/"), pull.UnsafeTitle)},
-					"body":   []string{fmt.Sprintf("Backport #%v to %v", b.c.Environment.Number, base)},
+					"body":   []string{bodyText},
+					"labels": labels,
 				}.Encode(),
 			},
 		})
@@ -162,8 +179,10 @@ func (b *Bot) BackportLocal(ctx context.Context, branch string) error {
 	return nil
 }
 
+const botBackportBranchPrefix = "bot/backport"
+
 func (b *Bot) backportBranchName(base string) string {
-	return fmt.Sprintf("bot/backport-%v-%v", b.c.Environment.Number, base)
+	return fmt.Sprintf("%s-%v-%v", botBackportBranchPrefix, b.c.Environment.Number, base)
 }
 
 // findBranches looks through the labels attached to a Pull Request for all the

bot/internal/bot/backport_test.go

@@ -17,9 +17,14 @@ limitations under the License.
 package bot
 
 import (
+	"context"
 	"testing"
 
 	"github.com/stretchr/testify/require"
+
+	"github.com/gravitational/shared-workflows/bot/internal/env"
+	"github.com/gravitational/shared-workflows/bot/internal/github"
+	"github.com/gravitational/shared-workflows/bot/internal/review"
 )
 
 func TestFindBranches(t *testing.T) {
@@ -35,3 +40,111 @@ func TestFindBranches(t *testing.T) {
 		"master",
 	})
 }
+
+func TestBackport(t *testing.T) {
+	buildTestBot := func(github Client) (*Bot, context.Context) {
+		r, _ := review.New(&review.Config{
+			CodeReviewers: map[string]review.Reviewer{"dev": review.Reviewer{
+				Team: "core",
+			}},
+			CodeReviewersOmit: map[string]bool{},
+			DocsReviewers:     map[string]review.Reviewer{},
+			DocsReviewersOmit: map[string]bool{},
+			Admins:            []string{},
+		})
+
+		return &Bot{
+			c: &Config{
+				Environment: &env.Environment{
+					Organization: "foo",
+					Author:       "dev",
+					Repository:   "bar",
+					Number:       42,
+					UnsafeBase:   "branch/v8",
+					UnsafeHead:   "fix",
+				},
+				GitHub: github,
+				Review: r,
+				Git:    gitDryRun,
+			},
+		}, context.Background()
+	}
+
+	tests := []struct {
+		desc       string
+		github     Client
+		assertFunc require.ValueAssertionFunc
+	}{
+		{
+			desc:       "pr without backport labels",
+			github:     &fakeGithub{},
+			assertFunc: require.Empty,
+		},
+		{
+			desc: "pr with backport label, no changelog",
+			github: &fakeGithub{
+				pull: github.PullRequest{
+					Author:       "dev",
+					Repository:   "Teleport",
+					Number:       42,
+					UnsafeTitle:  "Best PR",
+					UnsafeBody:   "This is PR body",
+					UnsafeLabels: []string{"backport/branch/v7"},
+				},
+				jobs: []github.Job{{Name: "Job1", ID: 1}},
+			},
+			assertFunc: func(t require.TestingT, i interface{}, i2 ...interface{}) {
+				comments, ok := i.([]github.Comment)
+				require.True(t, ok)
+				require.Len(t, comments, 1)
+				require.Equal(t,
+					`
+@dev See the table below for backport results.
+
+| Branch | Result |
+|--------|--------|
+| branch/v7 | [Create PR](https://github.com/foo/bar/compare/branch/v7...bot/backport-42-branch/v7?body=Backport+%2342+to+branch%2Fv7&expand=1&labels=no-changelog&title=%5Bv7%5D+Best+PR) |
+`, comments[0].Body)
+			},
+		},
+		{
+			desc: "pr with backport label and with changelog",
+			github: &fakeGithub{
+				pull: github.PullRequest{
+					Author:       "dev",
+					Repository:   "Teleport",
+					Number:       42,
+					UnsafeTitle:  "Best PR",
+					UnsafeBody:   "This is PR body\n\nchangelog: important change",
+					UnsafeLabels: []string{"backport/branch/v7"},
+				},
+				jobs: []github.Job{{Name: "Job1", ID: 1}},
+			},
+			assertFunc: func(t require.TestingT, i interface{}, i2 ...interface{}) {
+				comments, ok := i.([]github.Comment)
+				require.True(t, ok)
+				require.Len(t, comments, 1)
+				require.Equal(t,
+					`
+@dev See the table below for backport results.
+
+| Branch | Result |
+|--------|--------|
+| branch/v7 | [Create PR](https://github.com/foo/bar/compare/branch/v7...bot/backport-42-branch/v7?body=Backport+%2342+to+branch%2Fv7%0A%0Achangelog%3A+important+change%0A&expand=1&title=%5Bv7%5D+Best+PR) |
+`, comments[0].Body)
+			},
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.desc, func(t *testing.T) {
+			b, ctx := buildTestBot(test.github)
+
+			err := b.Backport(ctx)
+			require.NoError(t, err)
+
+			comments, _ := b.c.GitHub.ListComments(nil, "", "", 0)
+			test.assertFunc(t, comments)
+		})
+	}
+}

bot/internal/bot/bot.go

@@ -20,11 +20,11 @@ import (
 	"context"
 	"strings"
 
+	"github.com/gravitational/trace"
+
 	"github.com/gravitational/shared-workflows/bot/internal/env"
 	"github.com/gravitational/shared-workflows/bot/internal/github"
 	"github.com/gravitational/shared-workflows/bot/internal/review"
-
-	"github.com/gravitational/trace"
 )
 
 // Client implements the GitHub API.
@@ -44,7 +44,7 @@ type Client interface {
 	// GetPullRequest returns a specific Pull Request.
 	GetPullRequest(ctx context.Context, organization string, repository string, number int) (github.PullRequest, error)
 
-	// GetPullRequestWithCommitsd returns a specific Pull Request with commits.
+	// GetPullRequestWithCommits returns a specific Pull Request with commits.
 	GetPullRequestWithCommits(ctx context.Context, organization string, repository string, number int) (github.PullRequest, error)
 
 	// CreatePullRequest will create a Pull Request.
@@ -97,6 +97,9 @@ type Config struct {
 
 	// Review is used to get code and docs reviewers.
 	Review *review.Assignments
+
+	// Git is used to run git commands, uses dry run in tests.
+	Git func(...string) error
 }
 
 // CheckAndSetDefaults checks and sets defaults.

bot/internal/bot/bot_test.go

@@ -20,11 +20,11 @@ import (
 	"context"
 	"testing"
 
+	"github.com/stretchr/testify/require"
+
 	"github.com/gravitational/shared-workflows/bot/internal/env"
 	"github.com/gravitational/shared-workflows/bot/internal/github"
 	"github.com/gravitational/shared-workflows/bot/internal/review"
-
-	"github.com/stretchr/testify/require"
 )
 
 // TestClassifyChanges checks that PR contents are correctly parsed for docs and
@@ -311,6 +311,7 @@ func TestDoNotMerge(t *testing.T) {
 type fakeGithub struct {
 	files       []github.PullRequestFile
 	pull        github.PullRequest
+	jobs        []github.Job
 	reviewers   []string
 	reviews     []github.Review
 	orgMembers  map[string]struct{}
@@ -364,7 +365,7 @@ func (f *fakeGithub) ListWorkflowRuns(ctx context.Context, organization string,
 }
 
 func (f *fakeGithub) ListWorkflowJobs(ctx context.Context, organization string, repository string, runID int64) ([]github.Job, error) {
-	return nil, nil
+	return f.jobs, nil
 }
 
 func (f *fakeGithub) DeleteWorkflowRun(ctx context.Context, organization string, repository string, runID int64) error {
@@ -377,6 +378,10 @@ func (f *fakeGithub) IsOrgMember(ctx context.Context, user string, org string) (
 }
 
 func (f *fakeGithub) CreateComment(ctx context.Context, organization string, repository string, number int, comment string) error {
+	f.comments = append(f.comments, github.Comment{
+		Body: comment,
+	})
+
 	return nil
 }
 

bot/internal/bot/changelog.go

@@ -51,9 +51,11 @@ func (b *Bot) CheckChangelog(ctx context.Context) error {
 		return nil
 	}
 
-	changelogEntries, err := b.getChangelogEntries(ctx, pull.UnsafeBody)
-	if err != nil {
-		return trace.Wrap(err, "failed to get changelog entry")
+	changelogEntries := b.getChangelogEntries(pull.UnsafeBody)
+	if len(changelogEntries) == 0 {
+		return trace.Wrap(
+			b.logFailedCheck(ctx, "Changelog entry not found in the PR body. Please add a %q label to the PR, or changelog lines starting with `%s` followed by the changelog entries for the PR.", NoChangelogLabel, ChangelogPrefix),
+			"failed to get changelog entry")
 	}
 
 	for _, changelogEntry := range changelogEntries {
@@ -66,20 +68,18 @@ func (b *Bot) CheckChangelog(ctx context.Context) error {
 	return nil
 }
 
-func (b *Bot) getChangelogEntries(ctx context.Context, prBody string) ([]string, error) {
+func (b *Bot) getChangelogEntries(prBody string) []string {
 	changelogRegex := regexp.MustCompile(ChangelogRegex)
 
 	changelogMatches := changelogRegex.FindAllString(prBody, -1)
-	if len(changelogMatches) == 0 {
-		return nil, b.logFailedCheck(ctx, "Changelog entry not found in the PR body. Please add a %q label to the PR, or changelog lines starting with `%s` followed by the changelog entries for the PR.", NoChangelogLabel, ChangelogPrefix)
-	}
-
 	for i, changelogMatch := range changelogMatches {
 		changelogMatches[i] = changelogMatch[len(ChangelogPrefix):] // Case insensitive prefix removal
 	}
 
-	log.Printf("Found changelog entries %v", changelogMatches)
-	return changelogMatches, nil
+	if len(changelogMatches) > 0 {
+		log.Printf("Found changelog entries %v", changelogMatches)
+	}
+	return changelogMatches
 }
 
 // Checks for common issues with the changelog entry.