From 462284e2f5768cf04d71c7abd8c01eef20cff73d Mon Sep 17 00:00:00 2001
From: Lunny Xiao <xiaolunwen@gmail.com>
Date: Sat, 29 Jun 2019 21:38:22 +0800
Subject: [PATCH] Use batch insert on migrating repository to make the process
 faster (#7050)

* Use batch insert on migrating repository to make the process faster

* fix lint

* fix tests

* fix comments
---
 models/migrate.go                   | 131 ++++++----
 modules/migrations/base/comment.go  |   1 +
 modules/migrations/base/uploader.go |  14 +-
 modules/migrations/gitea.go         | 359 ++++++++++++++++------------
 modules/migrations/github.go        |   1 +
 modules/migrations/github_test.go   |   3 +
 modules/migrations/migrate.go       |  76 ++++--
 7 files changed, 343 insertions(+), 242 deletions(-)

diff --git a/models/migrate.go b/models/migrate.go
index 54f9a3e24c..b30e6a9d1c 100644
--- a/models/migrate.go
+++ b/models/migrate.go
@@ -6,38 +6,58 @@ package models
 
 import "github.com/go-xorm/xorm"
 
-// InsertIssue insert one issue to database
-func InsertIssue(issue *Issue, labelIDs []int64) error {
+// InsertMilestones creates milestones of repository.
+func InsertMilestones(ms ...*Milestone) (err error) {
+	if len(ms) == 0 {
+		return nil
+	}
+
 	sess := x.NewSession()
-	if err := sess.Begin(); err != nil {
+	defer sess.Close()
+	if err = sess.Begin(); err != nil {
 		return err
 	}
 
-	if err := insertIssue(sess, issue, labelIDs); err != nil {
+	// to return the id, so we should not use batch insert
+	for _, m := range ms {
+		if _, err = sess.NoAutoTime().Insert(m); err != nil {
+			return err
+		}
+	}
+
+	if _, err = sess.Exec("UPDATE `repository` SET num_milestones = num_milestones + ? WHERE id = ?", len(ms), ms[0].RepoID); err != nil {
 		return err
 	}
 	return sess.Commit()
 }
 
-func insertIssue(sess *xorm.Session, issue *Issue, labelIDs []int64) error {
-	if issue.MilestoneID > 0 {
-		sess.Incr("num_issues")
-		if issue.IsClosed {
-			sess.Incr("num_closed_issues")
-		}
-		if _, err := sess.ID(issue.MilestoneID).NoAutoTime().Update(new(Milestone)); err != nil {
+// InsertIssues insert issues to database
+func InsertIssues(issues ...*Issue) error {
+	sess := x.NewSession()
+	if err := sess.Begin(); err != nil {
+		return err
+	}
+
+	for _, issue := range issues {
+		if err := insertIssue(sess, issue); err != nil {
 			return err
 		}
 	}
+	return sess.Commit()
+}
+
+func insertIssue(sess *xorm.Session, issue *Issue) error {
 	if _, err := sess.NoAutoTime().Insert(issue); err != nil {
 		return err
 	}
-	var issueLabels = make([]IssueLabel, 0, len(labelIDs))
-	for _, labelID := range labelIDs {
+	var issueLabels = make([]IssueLabel, 0, len(issue.Labels))
+	var labelIDs = make([]int64, 0, len(issue.Labels))
+	for _, label := range issue.Labels {
 		issueLabels = append(issueLabels, IssueLabel{
 			IssueID: issue.ID,
-			LabelID: labelID,
+			LabelID: label.ID,
 		})
+		labelIDs = append(labelIDs, label.ID)
 	}
 	if _, err := sess.Insert(issueLabels); err != nil {
 		return err
@@ -61,12 +81,20 @@ func insertIssue(sess *xorm.Session, issue *Issue, labelIDs []int64) error {
 	if issue.IsClosed {
 		sess.Incr("num_closed_issues")
 	}
-	if _, err := sess.In("id", labelIDs).Update(new(Label)); err != nil {
+	if _, err := sess.In("id", labelIDs).NoAutoTime().Update(new(Label)); err != nil {
 		return err
 	}
 
 	if issue.MilestoneID > 0 {
-		if _, err := sess.ID(issue.MilestoneID).SetExpr("completeness", "num_closed_issues * 100 / num_issues").Update(new(Milestone)); err != nil {
+		sess.Incr("num_issues")
+		if issue.IsClosed {
+			sess.Incr("num_closed_issues")
+		}
+
+		if _, err := sess.ID(issue.MilestoneID).
+			SetExpr("completeness", "num_closed_issues * 100 / num_issues").
+			NoAutoTime().
+			Update(new(Milestone)); err != nil {
 			return err
 		}
 	}
@@ -74,72 +102,73 @@ func insertIssue(sess *xorm.Session, issue *Issue, labelIDs []int64) error {
 	return nil
 }
 
-// InsertComment inserted a comment
-func InsertComment(comment *Comment) error {
+// InsertIssueComments inserts many comments of issues.
+func InsertIssueComments(comments []*Comment) error {
+	if len(comments) == 0 {
+		return nil
+	}
+
+	var issueIDs = make(map[int64]bool)
+	for _, comment := range comments {
+		issueIDs[comment.IssueID] = true
+	}
+
 	sess := x.NewSession()
 	defer sess.Close()
 	if err := sess.Begin(); err != nil {
 		return err
 	}
-	if _, err := sess.NoAutoTime().Insert(comment); err != nil {
+	if _, err := sess.NoAutoTime().Insert(comments); err != nil {
 		return err
 	}
-	if _, err := sess.ID(comment.IssueID).Incr("num_comments").Update(new(Issue)); err != nil {
-		return err
+	for issueID := range issueIDs {
+		if _, err := sess.Exec("UPDATE issue set num_comments = (SELECT count(*) FROM comment WHERE issue_id = ?) WHERE id = ?", issueID, issueID); err != nil {
+			return err
+		}
 	}
 	return sess.Commit()
 }
 
-// InsertPullRequest inserted a pull request
-func InsertPullRequest(pr *PullRequest, labelIDs []int64) error {
+// InsertPullRequests inserted pull requests
+func InsertPullRequests(prs ...*PullRequest) error {
 	sess := x.NewSession()
 	defer sess.Close()
 	if err := sess.Begin(); err != nil {
 		return err
 	}
-	if err := insertIssue(sess, pr.Issue, labelIDs); err != nil {
-		return err
-	}
-	pr.IssueID = pr.Issue.ID
-	if _, err := sess.NoAutoTime().Insert(pr); err != nil {
-		return err
+	for _, pr := range prs {
+		if err := insertIssue(sess, pr.Issue); err != nil {
+			return err
+		}
+		pr.IssueID = pr.Issue.ID
+		if _, err := sess.NoAutoTime().Insert(pr); err != nil {
+			return err
+		}
 	}
+
 	return sess.Commit()
 }
 
-// MigrateRelease migrates release
-func MigrateRelease(rel *Release) error {
+// InsertReleases migrates release
+func InsertReleases(rels ...*Release) error {
 	sess := x.NewSession()
 	if err := sess.Begin(); err != nil {
 		return err
 	}
 
-	var oriRel = Release{
-		RepoID:  rel.RepoID,
-		TagName: rel.TagName,
-	}
-	exist, err := sess.Get(&oriRel)
-	if err != nil {
-		return err
-	}
-	if !exist {
+	for _, rel := range rels {
 		if _, err := sess.NoAutoTime().Insert(rel); err != nil {
 			return err
 		}
-	} else {
-		rel.ID = oriRel.ID
-		if _, err := sess.ID(rel.ID).Cols("target, title, note, is_tag, num_commits").Update(rel); err != nil {
+
+		for i := 0; i < len(rel.Attachments); i++ {
+			rel.Attachments[i].ReleaseID = rel.ID
+		}
+
+		if _, err := sess.NoAutoTime().Insert(rel.Attachments); err != nil {
 			return err
 		}
 	}
 
-	for i := 0; i < len(rel.Attachments); i++ {
-		rel.Attachments[i].ReleaseID = rel.ID
-	}
-
-	if _, err := sess.NoAutoTime().Insert(rel.Attachments); err != nil {
-		return err
-	}
-
 	return sess.Commit()
 }
diff --git a/modules/migrations/base/comment.go b/modules/migrations/base/comment.go
index 0ff0963f07..d89ec3a3f5 100644
--- a/modules/migrations/base/comment.go
+++ b/modules/migrations/base/comment.go
@@ -9,6 +9,7 @@ import "time"
 
 // Comment is a standard comment information
 type Comment struct {
+	IssueIndex  int64
 	PosterName  string
 	PosterEmail string
 	Created     time.Time
diff --git a/modules/migrations/base/uploader.go b/modules/migrations/base/uploader.go
index eaeb10314a..096a8ab8f0 100644
--- a/modules/migrations/base/uploader.go
+++ b/modules/migrations/base/uploader.go
@@ -5,14 +5,14 @@
 
 package base
 
-// Uploader uploads all the informations
+// Uploader uploads all the informations of one repository
 type Uploader interface {
 	CreateRepo(repo *Repository, includeWiki bool) error
-	CreateMilestone(milestone *Milestone) error
-	CreateRelease(release *Release) error
-	CreateLabel(label *Label) error
-	CreateIssue(issue *Issue) error
-	CreateComment(issueNumber int64, comment *Comment) error
-	CreatePullRequest(pr *PullRequest) error
+	CreateMilestones(milestones ...*Milestone) error
+	CreateReleases(releases ...*Release) error
+	CreateLabels(labels ...*Label) error
+	CreateIssues(issues ...*Issue) error
+	CreateComments(comments ...*Comment) error
+	CreatePullRequests(prs ...*PullRequest) error
 	Rollback() error
 }
diff --git a/modules/migrations/gitea.go b/modules/migrations/gitea.go
index 4e930fa831..7d5a50d307 100644
--- a/modules/migrations/gitea.go
+++ b/modules/migrations/gitea.go
@@ -76,238 +76,280 @@ func (g *GiteaLocalUploader) CreateRepo(repo *base.Repository, includeWiki bool)
 	return err
 }
 
-// CreateMilestone creates milestone
-func (g *GiteaLocalUploader) CreateMilestone(milestone *base.Milestone) error {
-	var deadline util.TimeStamp
-	if milestone.Deadline != nil {
-		deadline = util.TimeStamp(milestone.Deadline.Unix())
+// CreateMilestones creates milestones
+func (g *GiteaLocalUploader) CreateMilestones(milestones ...*base.Milestone) error {
+	var mss = make([]*models.Milestone, 0, len(milestones))
+	for _, milestone := range milestones {
+		var deadline util.TimeStamp
+		if milestone.Deadline != nil {
+			deadline = util.TimeStamp(milestone.Deadline.Unix())
+		}
+		if deadline == 0 {
+			deadline = util.TimeStamp(time.Date(9999, 1, 1, 0, 0, 0, 0, setting.UILocation).Unix())
+		}
+		var ms = models.Milestone{
+			RepoID:       g.repo.ID,
+			Name:         milestone.Title,
+			Content:      milestone.Description,
+			IsClosed:     milestone.State == "close",
+			DeadlineUnix: deadline,
+		}
+		if ms.IsClosed && milestone.Closed != nil {
+			ms.ClosedDateUnix = util.TimeStamp(milestone.Closed.Unix())
+		}
+		mss = append(mss, &ms)
 	}
-	if deadline == 0 {
-		deadline = util.TimeStamp(time.Date(9999, 1, 1, 0, 0, 0, 0, setting.UILocation).Unix())
-	}
-	var ms = models.Milestone{
-		RepoID:       g.repo.ID,
-		Name:         milestone.Title,
-		Content:      milestone.Description,
-		IsClosed:     milestone.State == "close",
-		DeadlineUnix: deadline,
-	}
-	if ms.IsClosed && milestone.Closed != nil {
-		ms.ClosedDateUnix = util.TimeStamp(milestone.Closed.Unix())
-	}
-	err := models.NewMilestone(&ms)
 
+	err := models.InsertMilestones(mss...)
 	if err != nil {
 		return err
 	}
-	g.milestones.Store(ms.Name, ms.ID)
+
+	for _, ms := range mss {
+		g.milestones.Store(ms.Name, ms.ID)
+	}
 	return nil
 }
 
-// CreateLabel creates label
-func (g *GiteaLocalUploader) CreateLabel(label *base.Label) error {
-	var lb = models.Label{
-		RepoID:      g.repo.ID,
-		Name:        label.Name,
-		Description: label.Description,
-		Color:       fmt.Sprintf("#%s", label.Color),
+// CreateLabels creates labels
+func (g *GiteaLocalUploader) CreateLabels(labels ...*base.Label) error {
+	var lbs = make([]*models.Label, 0, len(labels))
+	for _, label := range labels {
+		lbs = append(lbs, &models.Label{
+			RepoID:      g.repo.ID,
+			Name:        label.Name,
+			Description: label.Description,
+			Color:       fmt.Sprintf("#%s", label.Color),
+		})
 	}
-	err := models.NewLabel(&lb)
+
+	err := models.NewLabels(lbs...)
 	if err != nil {
 		return err
 	}
-	g.labels.Store(lb.Name, lb.ID)
+	for _, lb := range lbs {
+		g.labels.Store(lb.Name, lb)
+	}
 	return nil
 }
 
-// CreateRelease creates release
-func (g *GiteaLocalUploader) CreateRelease(release *base.Release) error {
-	var rel = models.Release{
-		RepoID:       g.repo.ID,
-		PublisherID:  g.doer.ID,
-		TagName:      release.TagName,
-		LowerTagName: strings.ToLower(release.TagName),
-		Target:       release.TargetCommitish,
-		Title:        release.Name,
-		Sha1:         release.TargetCommitish,
-		Note:         release.Body,
-		IsDraft:      release.Draft,
-		IsPrerelease: release.Prerelease,
-		IsTag:        false,
-		CreatedUnix:  util.TimeStamp(release.Created.Unix()),
-	}
-
-	// calc NumCommits
-	commit, err := g.gitRepo.GetCommit(rel.TagName)
-	if err != nil {
-		return fmt.Errorf("GetCommit: %v", err)
-	}
-	rel.NumCommits, err = commit.CommitsCount()
-	if err != nil {
-		return fmt.Errorf("CommitsCount: %v", err)
-	}
-
-	for _, asset := range release.Assets {
-		var attach = models.Attachment{
-			UUID:          gouuid.NewV4().String(),
-			Name:          asset.Name,
-			DownloadCount: int64(*asset.DownloadCount),
-			Size:          int64(*asset.Size),
-			CreatedUnix:   util.TimeStamp(asset.Created.Unix()),
+// CreateReleases creates releases
+func (g *GiteaLocalUploader) CreateReleases(releases ...*base.Release) error {
+	var rels = make([]*models.Release, 0, len(releases))
+	for _, release := range releases {
+		var rel = models.Release{
+			RepoID:       g.repo.ID,
+			PublisherID:  g.doer.ID,
+			TagName:      release.TagName,
+			LowerTagName: strings.ToLower(release.TagName),
+			Target:       release.TargetCommitish,
+			Title:        release.Name,
+			Sha1:         release.TargetCommitish,
+			Note:         release.Body,
+			IsDraft:      release.Draft,
+			IsPrerelease: release.Prerelease,
+			IsTag:        false,
+			CreatedUnix:  util.TimeStamp(release.Created.Unix()),
 		}
 
-		// download attachment
-		resp, err := http.Get(asset.URL)
+		// calc NumCommits
+		commit, err := g.gitRepo.GetCommit(rel.TagName)
 		if err != nil {
-			return err
+			return fmt.Errorf("GetCommit: %v", err)
 		}
-		defer resp.Body.Close()
-
-		localPath := attach.LocalPath()
-		if err = os.MkdirAll(path.Dir(localPath), os.ModePerm); err != nil {
-			return fmt.Errorf("MkdirAll: %v", err)
-		}
-
-		fw, err := os.Create(localPath)
+		rel.NumCommits, err = commit.CommitsCount()
 		if err != nil {
-			return fmt.Errorf("Create: %v", err)
-		}
-		defer fw.Close()
-
-		if _, err := io.Copy(fw, resp.Body); err != nil {
-			return err
+			return fmt.Errorf("CommitsCount: %v", err)
 		}
 
-		rel.Attachments = append(rel.Attachments, &attach)
+		for _, asset := range release.Assets {
+			var attach = models.Attachment{
+				UUID:          gouuid.NewV4().String(),
+				Name:          asset.Name,
+				DownloadCount: int64(*asset.DownloadCount),
+				Size:          int64(*asset.Size),
+				CreatedUnix:   util.TimeStamp(asset.Created.Unix()),
+			}
+
+			// download attachment
+			resp, err := http.Get(asset.URL)
+			if err != nil {
+				return err
+			}
+			defer resp.Body.Close()
+
+			localPath := attach.LocalPath()
+			if err = os.MkdirAll(path.Dir(localPath), os.ModePerm); err != nil {
+				return fmt.Errorf("MkdirAll: %v", err)
+			}
+
+			fw, err := os.Create(localPath)
+			if err != nil {
+				return fmt.Errorf("Create: %v", err)
+			}
+			defer fw.Close()
+
+			if _, err := io.Copy(fw, resp.Body); err != nil {
+				return err
+			}
+
+			rel.Attachments = append(rel.Attachments, &attach)
+		}
+
+		rels = append(rels, &rel)
 	}
-
-	return models.MigrateRelease(&rel)
+	return models.InsertReleases(rels...)
 }
 
-// CreateIssue creates issue
-func (g *GiteaLocalUploader) CreateIssue(issue *base.Issue) error {
-	var labelIDs []int64
-	for _, label := range issue.Labels {
-		id, ok := g.labels.Load(label.Name)
-		if !ok {
-			return fmt.Errorf("Label %s missing when create issue", label.Name)
+// CreateIssues creates issues
+func (g *GiteaLocalUploader) CreateIssues(issues ...*base.Issue) error {
+	var iss = make([]*models.Issue, 0, len(issues))
+	for _, issue := range issues {
+		var labels []*models.Label
+		for _, label := range issue.Labels {
+			lb, ok := g.labels.Load(label.Name)
+			if ok {
+				labels = append(labels, lb.(*models.Label))
+			}
 		}
-		labelIDs = append(labelIDs, id.(int64))
-	}
 
-	var milestoneID int64
-	if issue.Milestone != "" {
-		milestone, ok := g.milestones.Load(issue.Milestone)
-		if !ok {
-			return fmt.Errorf("Milestone %s missing when create issue", issue.Milestone)
+		var milestoneID int64
+		if issue.Milestone != "" {
+			milestone, ok := g.milestones.Load(issue.Milestone)
+			if ok {
+				milestoneID = milestone.(int64)
+			}
 		}
-		milestoneID = milestone.(int64)
+
+		var is = models.Issue{
+			RepoID:      g.repo.ID,
+			Repo:        g.repo,
+			Index:       issue.Number,
+			PosterID:    g.doer.ID,
+			Title:       issue.Title,
+			Content:     issue.Content,
+			IsClosed:    issue.State == "closed",
+			IsLocked:    issue.IsLocked,
+			MilestoneID: milestoneID,
+			Labels:      labels,
+			CreatedUnix: util.TimeStamp(issue.Created.Unix()),
+		}
+		if issue.Closed != nil {
+			is.ClosedUnix = util.TimeStamp(issue.Closed.Unix())
+		}
+		// TODO: add reactions
+		iss = append(iss, &is)
 	}
 
-	var is = models.Issue{
-		RepoID:      g.repo.ID,
-		Repo:        g.repo,
-		Index:       issue.Number,
-		PosterID:    g.doer.ID,
-		Title:       issue.Title,
-		Content:     issue.Content,
-		IsClosed:    issue.State == "closed",
-		IsLocked:    issue.IsLocked,
-		MilestoneID: milestoneID,
-		CreatedUnix: util.TimeStamp(issue.Created.Unix()),
-	}
-	if issue.Closed != nil {
-		is.ClosedUnix = util.TimeStamp(issue.Closed.Unix())
-	}
-
-	err := models.InsertIssue(&is, labelIDs)
+	err := models.InsertIssues(iss...)
 	if err != nil {
 		return err
 	}
-	g.issues.Store(issue.Number, is.ID)
-	// TODO: add reactions
-	return err
+	for _, is := range iss {
+		g.issues.Store(is.Index, is.ID)
+	}
+	return nil
 }
 
-// CreateComment creates comment
-func (g *GiteaLocalUploader) CreateComment(issueNumber int64, comment *base.Comment) error {
-	var issueID int64
-	if issueIDStr, ok := g.issues.Load(issueNumber); !ok {
-		issue, err := models.GetIssueByIndex(g.repo.ID, issueNumber)
+// CreateComments creates comments of issues
+func (g *GiteaLocalUploader) CreateComments(comments ...*base.Comment) error {
+	var cms = make([]*models.Comment, 0, len(comments))
+	for _, comment := range comments {
+		var issueID int64
+		if issueIDStr, ok := g.issues.Load(comment.IssueIndex); !ok {
+			issue, err := models.GetIssueByIndex(g.repo.ID, comment.IssueIndex)
+			if err != nil {
+				return err
+			}
+			issueID = issue.ID
+			g.issues.Store(comment.IssueIndex, issueID)
+		} else {
+			issueID = issueIDStr.(int64)
+		}
+
+		cms = append(cms, &models.Comment{
+			IssueID:     issueID,
+			Type:        models.CommentTypeComment,
+			PosterID:    g.doer.ID,
+			Content:     comment.Content,
+			CreatedUnix: util.TimeStamp(comment.Created.Unix()),
+		})
+
+		// TODO: Reactions
+	}
+
+	return models.InsertIssueComments(cms)
+}
+
+// CreatePullRequests creates pull requests
+func (g *GiteaLocalUploader) CreatePullRequests(prs ...*base.PullRequest) error {
+	var gprs = make([]*models.PullRequest, 0, len(prs))
+	for _, pr := range prs {
+		gpr, err := g.newPullRequest(pr)
 		if err != nil {
 			return err
 		}
-		issueID = issue.ID
-		g.issues.Store(issueNumber, issueID)
-	} else {
-		issueID = issueIDStr.(int64)
+		gprs = append(gprs, gpr)
 	}
-
-	var cm = models.Comment{
-		IssueID:     issueID,
-		Type:        models.CommentTypeComment,
-		PosterID:    g.doer.ID,
-		Content:     comment.Content,
-		CreatedUnix: util.TimeStamp(comment.Created.Unix()),
+	if err := models.InsertPullRequests(gprs...); err != nil {
+		return err
 	}
-	err := models.InsertComment(&cm)
-	// TODO: Reactions
-	return err
+	for _, pr := range gprs {
+		g.issues.Store(pr.Issue.Index, pr.Issue.ID)
+	}
+	return nil
 }
 
-// CreatePullRequest creates pull request
-func (g *GiteaLocalUploader) CreatePullRequest(pr *base.PullRequest) error {
-	var labelIDs []int64
+func (g *GiteaLocalUploader) newPullRequest(pr *base.PullRequest) (*models.PullRequest, error) {
+	var labels []*models.Label
 	for _, label := range pr.Labels {
-		id, ok := g.labels.Load(label.Name)
-		if !ok {
-			return fmt.Errorf("Label %s missing when create issue", label.Name)
+		lb, ok := g.labels.Load(label.Name)
+		if ok {
+			labels = append(labels, lb.(*models.Label))
 		}
-		labelIDs = append(labelIDs, id.(int64))
 	}
 
 	var milestoneID int64
 	if pr.Milestone != "" {
 		milestone, ok := g.milestones.Load(pr.Milestone)
-		if !ok {
-			return fmt.Errorf("Milestone %s missing when create issue", pr.Milestone)
+		if ok {
+			milestoneID = milestone.(int64)
 		}
-		milestoneID = milestone.(int64)
 	}
 
 	// download patch file
 	resp, err := http.Get(pr.PatchURL)
 	if err != nil {
-		return err
+		return nil, err
 	}
 	defer resp.Body.Close()
 	pullDir := filepath.Join(g.repo.RepoPath(), "pulls")
 	if err = os.MkdirAll(pullDir, os.ModePerm); err != nil {
-		return err
+		return nil, err
 	}
 	f, err := os.Create(filepath.Join(pullDir, fmt.Sprintf("%d.patch", pr.Number)))
 	if err != nil {
-		return err
+		return nil, err
 	}
 	defer f.Close()
 	_, err = io.Copy(f, resp.Body)
 	if err != nil {
-		return err
+		return nil, err
 	}
 
 	// set head information
 	pullHead := filepath.Join(g.repo.RepoPath(), "refs", "pull", fmt.Sprintf("%d", pr.Number))
 	if err := os.MkdirAll(pullHead, os.ModePerm); err != nil {
-		return err
+		return nil, err
 	}
 	p, err := os.Create(filepath.Join(pullHead, "head"))
 	if err != nil {
-		return err
+		return nil, err
 	}
 	defer p.Close()
 	_, err = p.WriteString(pr.Head.SHA)
 	if err != nil {
-		return err
+		return nil, err
 	}
 
 	var head = "unknown repository"
@@ -333,16 +375,16 @@ func (g *GiteaLocalUploader) CreatePullRequest(pr *base.PullRequest) error {
 				} else {
 					headBranch := filepath.Join(g.repo.RepoPath(), "refs", "heads", pr.Head.OwnerName, pr.Head.Ref)
 					if err := os.MkdirAll(filepath.Dir(headBranch), os.ModePerm); err != nil {
-						return err
+						return nil, err
 					}
 					b, err := os.Create(headBranch)
 					if err != nil {
-						return err
+						return nil, err
 					}
 					defer b.Close()
 					_, err = b.WriteString(pr.Head.SHA)
 					if err != nil {
-						return err
+						return nil, err
 					}
 					head = pr.Head.OwnerName + "/" + pr.Head.Ref
 				}
@@ -373,6 +415,7 @@ func (g *GiteaLocalUploader) CreatePullRequest(pr *base.PullRequest) error {
 			IsPull:      true,
 			IsClosed:    pr.State == "closed",
 			IsLocked:    pr.IsLocked,
+			Labels:      labels,
 			CreatedUnix: util.TimeStamp(pr.Created.Unix()),
 		},
 	}
@@ -389,7 +432,7 @@ func (g *GiteaLocalUploader) CreatePullRequest(pr *base.PullRequest) error {
 	// TODO: reactions
 	// TODO: assignees
 
-	return models.InsertPullRequest(&pullRequest, labelIDs)
+	return &pullRequest, nil
 }
 
 // Rollback when migrating failed, this will rollback all the changes.
diff --git a/modules/migrations/github.go b/modules/migrations/github.go
index 6847787ace..e6b532df9c 100644
--- a/modules/migrations/github.go
+++ b/modules/migrations/github.go
@@ -358,6 +358,7 @@ func (g *GithubDownloaderV3) GetComments(issueNumber int64) ([]*base.Comment, er
 				reactions = convertGithubReactions(comment.Reactions)
 			}
 			allComments = append(allComments, &base.Comment{
+				IssueIndex:  issueNumber,
 				PosterName:  *comment.User.Login,
 				PosterEmail: email,
 				Content:     *comment.Body,
diff --git a/modules/migrations/github_test.go b/modules/migrations/github_test.go
index c14292ecc6..700183bdc1 100644
--- a/modules/migrations/github_test.go
+++ b/modules/migrations/github_test.go
@@ -269,6 +269,7 @@ func TestGitHubDownloadRepo(t *testing.T) {
 	assert.EqualValues(t, 35, len(comments))
 	assert.EqualValues(t, []*base.Comment{
 		{
+			IssueIndex: 6,
 			PosterName: "bkcsoft",
 			Created:    time.Date(2016, 11, 02, 18, 59, 48, 0, time.UTC),
 			Content: `I would prefer a solution that is in the backend, unless it's required to have it update without reloading. Unfortunately I can't seem to find anything that does that :unamused: 
@@ -286,6 +287,7 @@ Also this would _require_ caching, since it will fetch huge amounts of data from
 			},
 		},
 		{
+			IssueIndex: 6,
 			PosterName: "joubertredrat",
 			Created:    time.Date(2016, 11, 02, 19, 16, 56, 0, time.UTC),
 			Content: `Yes, this plugin build on front-end, with backend I don't know too, but we can consider make component for this.
@@ -303,6 +305,7 @@ In my case I use ajax to get data, but build on frontend anyway
 			},
 		},
 		{
+			IssueIndex: 6,
 			PosterName: "xinity",
 			Created:    time.Date(2016, 11, 03, 13, 04, 56, 0, time.UTC),
 			Content: `following  @bkcsoft retention strategy in cache is a must if we don't want gitea to waste ressources.
diff --git a/modules/migrations/migrate.go b/modules/migrations/migrate.go
index 4b1229f949..3a4e6b2dbe 100644
--- a/modules/migrations/migrate.go
+++ b/modules/migrations/migrate.go
@@ -91,10 +91,8 @@ func migrateRepository(downloader base.Downloader, uploader base.Uploader, opts
 			return err
 		}
 
-		for _, milestone := range milestones {
-			if err := uploader.CreateMilestone(milestone); err != nil {
-				return err
-			}
+		if err := uploader.CreateMilestones(milestones...); err != nil {
+			return err
 		}
 	}
 
@@ -105,10 +103,8 @@ func migrateRepository(downloader base.Downloader, uploader base.Uploader, opts
 			return err
 		}
 
-		for _, label := range labels {
-			if err := uploader.CreateLabel(label); err != nil {
-				return err
-			}
+		if err := uploader.CreateLabels(labels...); err != nil {
+			return err
 		}
 	}
 
@@ -119,10 +115,8 @@ func migrateRepository(downloader base.Downloader, uploader base.Uploader, opts
 			return err
 		}
 
-		for _, release := range releases {
-			if err := uploader.CreateRelease(release); err != nil {
-				return err
-			}
+		if err := uploader.CreateReleases(releases...); err != nil {
+			return err
 		}
 	}
 
@@ -137,15 +131,18 @@ func migrateRepository(downloader base.Downloader, uploader base.Uploader, opts
 				if !opts.IgnoreIssueAuthor {
 					issue.Content = fmt.Sprintf("Author: @%s \n\n%s", issue.PosterName, issue.Content)
 				}
+			}
 
-				if err := uploader.CreateIssue(issue); err != nil {
-					return err
-				}
+			if err := uploader.CreateIssues(issues...); err != nil {
+				return err
+			}
 
-				if !opts.Comments {
-					continue
-				}
+			if !opts.Comments {
+				continue
+			}
 
+			var allComments = make([]*base.Comment, 0, 100)
+			for _, issue := range issues {
 				comments, err := downloader.GetComments(issue.Number)
 				if err != nil {
 					return err
@@ -154,9 +151,20 @@ func migrateRepository(downloader base.Downloader, uploader base.Uploader, opts
 					if !opts.IgnoreIssueAuthor {
 						comment.Content = fmt.Sprintf("Author: @%s \n\n%s", comment.PosterName, comment.Content)
 					}
-					if err := uploader.CreateComment(issue.Number, comment); err != nil {
+				}
+				allComments = append(allComments, comments...)
+
+				if len(allComments) >= 100 {
+					if err := uploader.CreateComments(allComments...); err != nil {
 						return err
 					}
+					allComments = make([]*base.Comment, 0, 100)
+				}
+			}
+
+			if len(allComments) > 0 {
+				if err := uploader.CreateComments(allComments...); err != nil {
+					return err
 				}
 			}
 
@@ -178,13 +186,17 @@ func migrateRepository(downloader base.Downloader, uploader base.Uploader, opts
 				if !opts.IgnoreIssueAuthor {
 					pr.Content = fmt.Sprintf("Author: @%s \n\n%s", pr.PosterName, pr.Content)
 				}
-				if err := uploader.CreatePullRequest(pr); err != nil {
-					return err
-				}
-				if !opts.Comments {
-					continue
-				}
+			}
+			if err := uploader.CreatePullRequests(prs...); err != nil {
+				return err
+			}
 
+			if !opts.Comments {
+				continue
+			}
+
+			var allComments = make([]*base.Comment, 0, 100)
+			for _, pr := range prs {
 				comments, err := downloader.GetComments(pr.Number)
 				if err != nil {
 					return err
@@ -193,11 +205,23 @@ func migrateRepository(downloader base.Downloader, uploader base.Uploader, opts
 					if !opts.IgnoreIssueAuthor {
 						comment.Content = fmt.Sprintf("Author: @%s \n\n%s", comment.PosterName, comment.Content)
 					}
-					if err := uploader.CreateComment(pr.Number, comment); err != nil {
+				}
+
+				allComments = append(allComments, comments...)
+
+				if len(allComments) >= 100 {
+					if err := uploader.CreateComments(allComments...); err != nil {
 						return err
 					}
+					allComments = make([]*base.Comment, 0, 100)
 				}
 			}
+			if len(allComments) > 0 {
+				if err := uploader.CreateComments(allComments...); err != nil {
+					return err
+				}
+			}
+
 			if len(prs) < 100 {
 				break
 			}