dmitri.shuralyov.com/service/change/githubapi

Add timeline pagination to ListTimeline.

This helps with displaying large PRs that have over 100 timeline items
(e.g., https://github.com/neelance/go/pull/7).

The implementation is based the similar issues service ListTimeline,
see https://github.com/shurcooL/issues/commit/4081aa59e957752abbfc6b6fdab72c3bbc1c1dec.
dmitshur committed 5 years ago commit 761d04bf40c2c9ef3f63f776a7e525c6290464a3
Showing partial commit. Full Commit
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githubapi/githubapi.go
@@ -257,38 +257,34 @@ func (s service) ListTimeline(ctx context.Context, rs string, id uint64, opt *ch
	repo, err := ghRepoSpec(rs)
	if err != nil {
		// TODO: Map to 400 Bad Request HTTP error.
		return nil, err
	}

	type comment struct { // Comment fields.
		Author          *githubV4Actor
		PublishedAt     githubv4.DateTime
		LastEditedAt    *githubv4.DateTime
		Editor          *githubV4Actor
		Body            string
		ReactionGroups  reactionGroups
		ViewerCanUpdate bool
	}
	type event struct { // Common fields for all events.
		Actor     *githubV4Actor
		CreatedAt githubv4.DateTime
	}
	var q struct {
		Repository struct {
			PullRequest struct {
				Author          *githubV4Actor
				PublishedAt     githubv4.DateTime
				LastEditedAt    *githubv4.DateTime
				Editor          *githubV4Actor
				Body            githubv4.String
				ReactionGroups  reactionGroups
				ViewerCanUpdate bool
				comment `graphql:"...@include(if:$firstPage)"` // Fetch the PR description only on first page.

				Timeline struct {
					Nodes []struct {
						Typename     string `graphql:"__typename"`
						IssueComment struct {
							DatabaseID      uint64
							Author          *githubV4Actor
							PublishedAt     githubv4.DateTime
							LastEditedAt    *githubv4.DateTime
							Editor          *githubV4Actor
							Body            string
							ReactionGroups  reactionGroups
							ViewerCanUpdate bool
							DatabaseID uint64
							comment
						} `graphql:"...on IssueComment"`
						ClosedEvent struct {
							event
							Closer struct {
								Typename    string `graphql:"__typename"`
@@ -360,11 +356,15 @@ func (s service) ListTimeline(ctx context.Context, rs string, id uint64, opt *ch
						// TODO: Wait for GitHub to add support.
						//CommentDeletedEvent struct {
						//	event
						//} `graphql:"...on CommentDeletedEvent"`
					}
				} `graphql:"timeline(first:100)"` // TODO: Pagination...
					PageInfo struct {
						EndCursor   githubv4.String
						HasNextPage githubv4.Boolean
					}
				} `graphql:"timeline(first:100,after:$timelineCursor)"`

				// Need to use PullRequest.Reviews rather than PullRequest.Timeline.PullRequestReview,
				// because the latter is missing single-inline-reply reviews (as of 2018-02-08).
				Reviews struct {
					Nodes []struct {
@@ -384,204 +384,214 @@ func (s service) ListTimeline(ctx context.Context, rs string, id uint64, opt *ch
								Body             string
								ReactionGroups   reactionGroups
							}
						} `graphql:"comments(first:100)"` // TODO: Pagination... Figure out how to make pagination across 2 resource types work...
					}
				} `graphql:"reviews(first:100)"` // TODO: Pagination... Figure out how to make pagination across 2 resource types work...
				} `graphql:"reviews(first:100)@include(if:$firstPage)"` // TODO: Pagination... Figure out how to make pagination across 2 resource types work...
			} `graphql:"pullRequest(number:$prNumber)"`
		} `graphql:"repository(owner:$repositoryOwner,name:$repositoryName)"`
		Viewer githubV4User
	}
	variables := map[string]interface{}{
		"repositoryOwner": githubv4.String(repo.Owner),
		"repositoryName":  githubv4.String(repo.Repo),
		"prNumber":        githubv4.Int(id),
		"firstPage":       githubv4.Boolean(true),
		"timelineCursor":  (*githubv4.String)(nil),
	}
	err = s.clV4.Query(ctx, &q, variables)
	if err != nil {
		return nil, err
	}
	var timeline []interface{}
	{
		pr := q.Repository.PullRequest
		var edited *change.Edited
		if pr.LastEditedAt != nil {
			edited = &change.Edited{
				By: ghActor(pr.Editor),
				At: pr.LastEditedAt.Time,
			}
		}
		timeline = append(timeline, change.Comment{
			ID:        prDescriptionCommentID,
			User:      ghActor(pr.Author),
			CreatedAt: pr.PublishedAt.Time,
			Edited:    edited,
			Body:      string(pr.Body),
			Reactions: ghReactions(pr.ReactionGroups, ghUser(&q.Viewer)),
			Editable:  pr.ViewerCanUpdate,
		})
	}
	for _, node := range q.Repository.PullRequest.Timeline.Nodes {
		if node.Typename != "IssueComment" {
			continue
	var timeline []interface{} // Of type change.Comment, change.Review, change.TimelineItem.
	for {
		err := s.clV4.Query(ctx, &q, variables)
		if err != nil {
			return nil, err
		}
		comment := node.IssueComment
		var edited *change.Edited
		if comment.LastEditedAt != nil {
			edited = &change.Edited{
				By: ghActor(comment.Editor),
				At: comment.LastEditedAt.Time,
		if variables["firstPage"].(githubv4.Boolean) {
			pr := q.Repository.PullRequest.comment // PR description comment.
			var edited *change.Edited
			if pr.LastEditedAt != nil {
				edited = &change.Edited{
					By: ghActor(pr.Editor),
					At: pr.LastEditedAt.Time,
				}
			}
			timeline = append(timeline, change.Comment{
				ID:        prDescriptionCommentID,
				User:      ghActor(pr.Author),
				CreatedAt: pr.PublishedAt.Time,
				Edited:    edited,
				Body:      pr.Body,
				Reactions: ghReactions(pr.ReactionGroups, ghUser(&q.Viewer)),
				Editable:  pr.ViewerCanUpdate,
			})
		}
		timeline = append(timeline, change.Comment{
			ID:        fmt.Sprintf("c%d", comment.DatabaseID),
			User:      ghActor(comment.Author),
			CreatedAt: comment.PublishedAt.Time,
			Edited:    edited,
			Body:      comment.Body,
			Reactions: ghReactions(comment.ReactionGroups, ghUser(&q.Viewer)),
			Editable:  comment.ViewerCanUpdate,
		})
	}
	for _, review := range q.Repository.PullRequest.Reviews.Nodes {
		state, ok := ghPRReviewState(review.State)
		if !ok {
			continue
		}
		var edited *change.Edited
		if review.LastEditedAt != nil {
			edited = &change.Edited{
				By: ghActor(review.Editor),
				At: review.LastEditedAt.Time,
		for _, node := range q.Repository.PullRequest.Timeline.Nodes {
			if node.Typename != "IssueComment" {
				continue
			}
		}
		var cs []change.InlineComment
		for _, comment := range review.Comments.Nodes {
			cs = append(cs, change.InlineComment{
				ID:        fmt.Sprintf("rc%d", comment.DatabaseID),
				File:      comment.Path,
				Line:      comment.OriginalPosition, // TODO: This isn't line in file, it's line *in the diff*. Take it into account, compute real line, etc.
			comment := node.IssueComment
			var edited *change.Edited
			if comment.LastEditedAt != nil {
				edited = &change.Edited{
					By: ghActor(comment.Editor),
					At: comment.LastEditedAt.Time,
				}
			}
			timeline = append(timeline, change.Comment{
				ID:        fmt.Sprintf("c%d", comment.DatabaseID),
				User:      ghActor(comment.Author),
				CreatedAt: comment.PublishedAt.Time,
				Edited:    edited,
				Body:      comment.Body,
				Reactions: ghReactions(comment.ReactionGroups, ghUser(&q.Viewer)),
				Editable:  comment.ViewerCanUpdate,
			})
		}
		sort.Slice(cs, func(i, j int) bool {
			if cs[i].File == cs[j].File {
				return cs[i].Line < cs[j].Line
		if variables["firstPage"].(githubv4.Boolean) {
			for _, review := range q.Repository.PullRequest.Reviews.Nodes {
				state, ok := ghPRReviewState(review.State)
				if !ok {
					continue
				}
				var edited *change.Edited
				if review.LastEditedAt != nil {
					edited = &change.Edited{
						By: ghActor(review.Editor),
						At: review.LastEditedAt.Time,
					}
				}
				var cs []change.InlineComment
				for _, comment := range review.Comments.Nodes {
					cs = append(cs, change.InlineComment{
						ID:        fmt.Sprintf("rc%d", comment.DatabaseID),
						File:      comment.Path,
						Line:      comment.OriginalPosition, // TODO: This isn't line in file, it's line *in the diff*. Take it into account, compute real line, etc.
						Body:      comment.Body,
						Reactions: ghReactions(comment.ReactionGroups, ghUser(&q.Viewer)),
					})
				}
				sort.Slice(cs, func(i, j int) bool {
					if cs[i].File == cs[j].File {
						return cs[i].Line < cs[j].Line
					}
					return cs[i].File < cs[j].File
				})
				timeline = append(timeline, change.Review{
					ID:        fmt.Sprintf("r%d", review.DatabaseID),
					User:      ghActor(review.Author),
					CreatedAt: review.PublishedAt.Time,
					Edited:    edited,
					State:     state,
					Body:      review.Body,
					Editable:  review.ViewerCanUpdate,
					Comments:  cs,
				})
			}
			return cs[i].File < cs[j].File
		})
		timeline = append(timeline, change.Review{
			ID:        fmt.Sprintf("r%d", review.DatabaseID),
			User:      ghActor(review.Author),
			CreatedAt: review.PublishedAt.Time,
			Edited:    edited,
			State:     state,
			Body:      review.Body,
			Editable:  review.ViewerCanUpdate,
			Comments:  cs,
		})
	}
	for _, event := range q.Repository.PullRequest.Timeline.Nodes {
		e := change.TimelineItem{
			//ID: 0, // TODO.
		}
		switch event.Typename {
		case "ClosedEvent":
			e.Actor = ghActor(event.ClosedEvent.Actor)
			e.CreatedAt = event.ClosedEvent.CreatedAt.Time
			switch event.ClosedEvent.Closer.Typename {
			case "PullRequest":
				pr := event.ClosedEvent.Closer.PullRequest
				e.Payload = change.ClosedEvent{
					Closer: change.Change{
						State: ghPRState(pr.State),
						Title: pr.Title,
		for _, event := range q.Repository.PullRequest.Timeline.Nodes {
			e := change.TimelineItem{
				//ID: 0, // TODO.
			}
			switch event.Typename {
			case "ClosedEvent":
				e.Actor = ghActor(event.ClosedEvent.Actor)
				e.CreatedAt = event.ClosedEvent.CreatedAt.Time
				switch event.ClosedEvent.Closer.Typename {
				case "PullRequest":
					pr := event.ClosedEvent.Closer.PullRequest
					e.Payload = change.ClosedEvent{
						Closer: change.Change{
							State: ghPRState(pr.State),
							Title: pr.Title,
						},
						CloserHTMLURL: s.rtr.PullRequestURL(ctx, pr.Repository.Owner.Login, pr.Repository.Name, pr.Number),
					}
				case "Commit":
					c := event.ClosedEvent.Closer.Commit
					e.Payload = change.ClosedEvent{
						Closer: change.Commit{
							SHA:     c.OID,
							Message: c.Message,
							Author:  users.User{AvatarURL: c.Author.AvatarURL},
						},
						CloserHTMLURL: c.URL,
					}
				default:
					e.Payload = change.ClosedEvent{}
				}
			case "ReopenedEvent":
				e.Actor = ghActor(event.ReopenedEvent.Actor)
				e.CreatedAt = event.ReopenedEvent.CreatedAt.Time
				e.Payload = change.ReopenedEvent{}
			case "RenamedTitleEvent":
				e.Actor = ghActor(event.RenamedTitleEvent.Actor)
				e.CreatedAt = event.RenamedTitleEvent.CreatedAt.Time
				e.Payload = change.RenamedEvent{
					From: event.RenamedTitleEvent.PreviousTitle,
					To:   event.RenamedTitleEvent.CurrentTitle,
				}
			case "LabeledEvent":
				e.Actor = ghActor(event.LabeledEvent.Actor)
				e.CreatedAt = event.LabeledEvent.CreatedAt.Time
				e.Payload = change.LabeledEvent{
					Label: issues.Label{
						Name:  event.LabeledEvent.Label.Name,
						Color: ghColor(event.LabeledEvent.Label.Color),
					},
					CloserHTMLURL: s.rtr.PullRequestURL(ctx, pr.Repository.Owner.Login, pr.Repository.Name, pr.Number),
				}
			case "Commit":
				c := event.ClosedEvent.Closer.Commit
				e.Payload = change.ClosedEvent{
					Closer: change.Commit{
						SHA:     c.OID,
						Message: c.Message,
						Author:  users.User{AvatarURL: c.Author.AvatarURL},
			case "UnlabeledEvent":
				e.Actor = ghActor(event.UnlabeledEvent.Actor)
				e.CreatedAt = event.UnlabeledEvent.CreatedAt.Time
				e.Payload = change.UnlabeledEvent{
					Label: issues.Label{
						Name:  event.UnlabeledEvent.Label.Name,
						Color: ghColor(event.UnlabeledEvent.Label.Color),
					},
					CloserHTMLURL: c.URL,
				}
			case "ReviewRequestedEvent":
				e.Actor = ghActor(event.ReviewRequestedEvent.Actor)
				e.CreatedAt = event.ReviewRequestedEvent.CreatedAt.Time
				e.Payload = change.ReviewRequestedEvent{
					RequestedReviewer: ghUser(event.ReviewRequestedEvent.RequestedReviewer.User),
				}
			case "ReviewRequestRemovedEvent":
				e.Actor = ghActor(event.ReviewRequestRemovedEvent.Actor)
				e.CreatedAt = event.ReviewRequestRemovedEvent.CreatedAt.Time
				e.Payload = change.ReviewRequestRemovedEvent{
					RequestedReviewer: ghUser(event.ReviewRequestRemovedEvent.RequestedReviewer.User),
				}
			case "MergedEvent":
				e.Actor = ghActor(event.MergedEvent.Actor)
				e.CreatedAt = event.MergedEvent.CreatedAt.Time
				e.Payload = change.MergedEvent{
					CommitID:      event.MergedEvent.Commit.OID,
					CommitHTMLURL: event.MergedEvent.Commit.URL,
					RefName:       event.MergedEvent.MergeRefName,
				}
			case "HeadRefDeletedEvent":
				e.Actor = ghActor(event.HeadRefDeletedEvent.Actor)
				e.CreatedAt = event.HeadRefDeletedEvent.CreatedAt.Time
				e.Payload = change.DeletedEvent{
					Type: "branch",
					Name: event.HeadRefDeletedEvent.HeadRefName,
				}
			// TODO: Wait for GitHub to add support.
			//case "CommentDeletedEvent":
			//	e.Actor = ghActor(event.CommentDeletedEvent.Actor)
			//	e.CreatedAt = event.CommentDeletedEvent.CreatedAt.Time
			default:
				e.Payload = change.ClosedEvent{}
			}
		case "ReopenedEvent":
			e.Actor = ghActor(event.ReopenedEvent.Actor)
			e.CreatedAt = event.ReopenedEvent.CreatedAt.Time
			e.Payload = change.ReopenedEvent{}
		case "RenamedTitleEvent":
			e.Actor = ghActor(event.RenamedTitleEvent.Actor)
			e.CreatedAt = event.RenamedTitleEvent.CreatedAt.Time
			e.Payload = change.RenamedEvent{
				From: event.RenamedTitleEvent.PreviousTitle,
				To:   event.RenamedTitleEvent.CurrentTitle,
			}
		case "LabeledEvent":
			e.Actor = ghActor(event.LabeledEvent.Actor)
			e.CreatedAt = event.LabeledEvent.CreatedAt.Time
			e.Payload = change.LabeledEvent{
				Label: issues.Label{
					Name:  event.LabeledEvent.Label.Name,
					Color: ghColor(event.LabeledEvent.Label.Color),
				},
			}
		case "UnlabeledEvent":
			e.Actor = ghActor(event.UnlabeledEvent.Actor)
			e.CreatedAt = event.UnlabeledEvent.CreatedAt.Time
			e.Payload = change.UnlabeledEvent{
				Label: issues.Label{
					Name:  event.UnlabeledEvent.Label.Name,
					Color: ghColor(event.UnlabeledEvent.Label.Color),
				},
			}
		case "ReviewRequestedEvent":
			e.Actor = ghActor(event.ReviewRequestedEvent.Actor)
			e.CreatedAt = event.ReviewRequestedEvent.CreatedAt.Time
			e.Payload = change.ReviewRequestedEvent{
				RequestedReviewer: ghUser(event.ReviewRequestedEvent.RequestedReviewer.User),
			}
		case "ReviewRequestRemovedEvent":
			e.Actor = ghActor(event.ReviewRequestRemovedEvent.Actor)
			e.CreatedAt = event.ReviewRequestRemovedEvent.CreatedAt.Time
			e.Payload = change.ReviewRequestRemovedEvent{
				RequestedReviewer: ghUser(event.ReviewRequestRemovedEvent.RequestedReviewer.User),
				continue
			}
		case "MergedEvent":
			e.Actor = ghActor(event.MergedEvent.Actor)
			e.CreatedAt = event.MergedEvent.CreatedAt.Time
			e.Payload = change.MergedEvent{
				CommitID:      event.MergedEvent.Commit.OID,
				CommitHTMLURL: event.MergedEvent.Commit.URL,
				RefName:       event.MergedEvent.MergeRefName,
			}
		case "HeadRefDeletedEvent":
			e.Actor = ghActor(event.HeadRefDeletedEvent.Actor)
			e.CreatedAt = event.HeadRefDeletedEvent.CreatedAt.Time
			e.Payload = change.DeletedEvent{
				Type: "branch",
				Name: event.HeadRefDeletedEvent.HeadRefName,
			}
		// TODO: Wait for GitHub to add support.
		//case "CommentDeletedEvent":
		//	e.Actor = ghActor(event.CommentDeletedEvent.Actor)
		//	e.CreatedAt = event.CommentDeletedEvent.CreatedAt.Time
		default:
			continue
			timeline = append(timeline, e)
		}
		if !q.Repository.PullRequest.Timeline.PageInfo.HasNextPage {
			break
		}
		timeline = append(timeline, e)
		variables["firstPage"] = githubv4.Boolean(false)
		variables["timelineCursor"] = githubv4.NewString(q.Repository.PullRequest.Timeline.PageInfo.EndCursor)
	}

	// We can't just delegate pagination to GitHub because our timeline items don't match up 1:1,
	// we want to skip Commit in the timeline, etc.
	// We can't just delegate pagination to GitHub because our timeline items may not match up 1:1,
	// e.g., we want to skip Commit in the timeline, etc. (At least for now; may reconsider later.)
	if opt != nil {
		start := opt.Start
		if start > len(timeline) {
			start = len(timeline)
		}