Make wiki default branch name changable (#29603)

Fix #29000
Fix #28685
Fix #18568

Related: #27497

And by the way fix #24036, add a Cancel button there (one line)

17 files changed, 232 insertions, 89 deletions

diff --git a/models/migrations/migrations.go b/models/migrations/migrations.go
index 9d288ec2bd..d40866f3e9 100644
--- a/models/migrations/migrations.go
+++ b/models/migrations/migrations.go
@@ -562,6 +562,8 @@ var migrations = []Migration{
 	NewMigration("Use Slug instead of ID for Badges", v1_22.UseSlugInsteadOfIDForBadges),
 	// v288 -> v289
 	NewMigration("Add user_blocking table", v1_22.AddUserBlockingTable),
+	// v289 -> v290
+	NewMigration("Add default_wiki_branch to repository table", v1_22.AddDefaultWikiBranch),
 }
 
 // GetCurrentDBVersion returns the current db version
diff --git a/models/migrations/v1_22/v289.go b/models/migrations/v1_22/v289.go
new file mode 100644
index 0000000000..e2dfc48715
--- /dev/null
+++ b/models/migrations/v1_22/v289.go
@@ -0,0 +1,18 @@
+// Copyright 2024 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package v1_22 //nolint
+
+import "xorm.io/xorm"
+
+func AddDefaultWikiBranch(x *xorm.Engine) error {
+	type Repository struct {
+		ID                int64
+		DefaultWikiBranch string
+	}
+	if err := x.Sync(&Repository{}); err != nil {
+		return err
+	}
+	_, err := x.Exec("UPDATE `repository` SET default_wiki_branch = 'master' WHERE (default_wiki_branch IS NULL) OR (default_wiki_branch = '')")
+	return err
+}
diff --git a/models/repo/repo.go b/models/repo/repo.go
index f6758f1591..1d17e565ae 100644
--- a/models/repo/repo.go
+++ b/models/repo/repo.go
@@ -136,6 +136,7 @@ type Repository struct {
 	OriginalServiceType api.GitServiceType `xorm:"index"`
 	OriginalURL         string             `xorm:"VARCHAR(2048)"`
 	DefaultBranch       string
+	DefaultWikiBranch   string
 
 	NumWatches          int
 	NumStars            int
@@ -285,6 +286,9 @@ func (repo *Repository) AfterLoad() {
 	repo.NumOpenMilestones = repo.NumMilestones - repo.NumClosedMilestones
 	repo.NumOpenProjects = repo.NumProjects - repo.NumClosedProjects
 	repo.NumOpenActionRuns = repo.NumActionRuns - repo.NumClosedActionRuns
+	if repo.DefaultWikiBranch == "" {
+		repo.DefaultWikiBranch = setting.Repository.DefaultBranch
+	}
 }
 
 // LoadAttributes loads attributes of the repository.
diff --git a/modules/git/repo_base_gogit.go b/modules/git/repo_base_gogit.go
index 3ca5eb36c6..0cd07dcdc8 100644
--- a/modules/git/repo_base_gogit.go
+++ b/modules/git/repo_base_gogit.go
@@ -8,11 +8,11 @@ package git
 
 import (
 	"context"
-	"errors"
 	"path/filepath"
 
 	gitealog "code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/util"
 
 	"github.com/go-git/go-billy/v5"
 	"github.com/go-git/go-billy/v5/osfs"
@@ -52,7 +52,7 @@ func OpenRepository(ctx context.Context, repoPath string) (*Repository, error) {
 	if err != nil {
 		return nil, err
 	} else if !isDir(repoPath) {
-		return nil, errors.New("no such file or directory")
+		return nil, util.NewNotExistErrorf("no such file or directory")
 	}
 
 	fs := osfs.New(repoPath)
diff --git a/modules/git/repo_base_nogogit.go b/modules/git/repo_base_nogogit.go
index 86b6a93567..7f6512200b 100644
--- a/modules/git/repo_base_nogogit.go
+++ b/modules/git/repo_base_nogogit.go
@@ -9,10 +9,10 @@ package git
 import (
 	"bufio"
 	"context"
-	"errors"
 	"path/filepath"
 
 	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/util"
 )
 
 func init() {
@@ -54,7 +54,7 @@ func OpenRepository(ctx context.Context, repoPath string) (*Repository, error) {
 	if err != nil {
 		return nil, err
 	} else if !isDir(repoPath) {
-		return nil, errors.New("no such file or directory")
+		return nil, util.NewNotExistErrorf("no such file or directory")
 	}
 
 	// Now because of some insanity with git cat-file not immediately failing if not run in a valid git directory we need to run git rev-parse first!
diff --git a/options/locale/locale_en-US.ini b/options/locale/locale_en-US.ini
index 3fc74959ca..59aae68cae 100644
--- a/options/locale/locale_en-US.ini
+++ b/options/locale/locale_en-US.ini
@@ -2092,6 +2092,8 @@ settings.branches.add_new_rule = Add New Rule
 settings.advanced_settings = Advanced Settings
 settings.wiki_desc = Enable Repository Wiki
 settings.use_internal_wiki = Use Built-In Wiki
+settings.default_wiki_branch_name = Default Wiki Branch Name
+settings.failed_to_change_default_wiki_branch = Failed to change the default wiki branch.
 settings.use_external_wiki = Use External Wiki
 settings.external_wiki_url = External Wiki URL
 settings.external_wiki_url_error = The external wiki URL is not a valid URL.
diff --git a/routers/web/repo/setting/setting.go b/routers/web/repo/setting/setting.go
index 992a980d9e..e045e3b8dc 100644
--- a/routers/web/repo/setting/setting.go
+++ b/routers/web/repo/setting/setting.go
@@ -488,6 +488,13 @@ func SettingsPost(ctx *context.Context) {
 			}
 		}
 
+		if form.DefaultWikiBranch != "" {
+			if err := wiki_service.ChangeDefaultWikiBranch(ctx, repo, form.DefaultWikiBranch); err != nil {
+				log.Error("ChangeDefaultWikiBranch failed, err: %v", err)
+				ctx.Flash.Warning(ctx.Tr("repo.settings.failed_to_change_default_wiki_branch"))
+			}
+		}
+
 		if form.EnableIssues && form.EnableExternalTracker && !unit_model.TypeExternalTracker.UnitGlobalDisabled() {
 			if !validation.IsValidExternalURL(form.ExternalTrackerURL) {
 				ctx.Flash.Error(ctx.Tr("repo.settings.external_tracker_url_error"))
diff --git a/routers/web/repo/wiki.go b/routers/web/repo/wiki.go
index 91cf727e2c..88b63da88d 100644
--- a/routers/web/repo/wiki.go
+++ b/routers/web/repo/wiki.go
@@ -93,17 +93,32 @@ func findEntryForFile(commit *git.Commit, target string) (*git.TreeEntry, error)
 }
 
 func findWikiRepoCommit(ctx *context.Context) (*git.Repository, *git.Commit, error) {
-	wikiRepo, err := gitrepo.OpenWikiRepository(ctx, ctx.Repo.Repository)
-	if err != nil {
-		ctx.ServerError("OpenRepository", err)
-		return nil, nil, err
+	wikiGitRepo, errGitRepo := gitrepo.OpenWikiRepository(ctx, ctx.Repo.Repository)
+	if errGitRepo != nil {
+		ctx.ServerError("OpenRepository", errGitRepo)
+		return nil, nil, errGitRepo
 	}
 
-	commit, err := wikiRepo.GetBranchCommit(wiki_service.DefaultBranch)
-	if err != nil {
-		return wikiRepo, nil, err
+	commit, errCommit := wikiGitRepo.GetBranchCommit(ctx.Repo.Repository.DefaultWikiBranch)
+	if git.IsErrNotExist(errCommit) {
+		// if the default branch recorded in database is out of sync, then re-sync it
+		gitRepoDefaultBranch, errBranch := wikiGitRepo.GetDefaultBranch()
+		if errBranch != nil {
+			return wikiGitRepo, nil, errBranch
+		}
+		// update the default branch in the database
+		errDb := repo_model.UpdateRepositoryCols(ctx, &repo_model.Repository{ID: ctx.Repo.Repository.ID, DefaultWikiBranch: gitRepoDefaultBranch}, "default_wiki_branch")
+		if errDb != nil {
+			return wikiGitRepo, nil, errDb
+		}
+		ctx.Repo.Repository.DefaultWikiBranch = gitRepoDefaultBranch
+		// retry to get the commit from the correct default branch
+		commit, errCommit = wikiGitRepo.GetBranchCommit(ctx.Repo.Repository.DefaultWikiBranch)
 	}
-	return wikiRepo, commit, nil
+	if errCommit != nil {
+		return wikiGitRepo, nil, errCommit
+	}
+	return wikiGitRepo, commit, nil
 }
 
 // wikiContentsByEntry returns the contents of the wiki page referenced by the
@@ -316,7 +331,7 @@ func renderViewPage(ctx *context.Context) (*git.Repository, *git.TreeEntry) {
 	}
 
 	// get commit count - wiki revisions
-	commitsCount, _ := wikiRepo.FileCommitsCount(wiki_service.DefaultBranch, pageFilename)
+	commitsCount, _ := wikiRepo.FileCommitsCount(ctx.Repo.Repository.DefaultWikiBranch, pageFilename)
 	ctx.Data["CommitCount"] = commitsCount
 
 	return wikiRepo, entry
@@ -368,7 +383,7 @@ func renderRevisionPage(ctx *context.Context) (*git.Repository, *git.TreeEntry)
 	ctx.Data["footerContent"] = ""
 
 	// get commit count - wiki revisions
-	commitsCount, _ := wikiRepo.FileCommitsCount(wiki_service.DefaultBranch, pageFilename)
+	commitsCount, _ := wikiRepo.FileCommitsCount(ctx.Repo.Repository.DefaultWikiBranch, pageFilename)
 	ctx.Data["CommitCount"] = commitsCount
 
 	// get page
@@ -380,7 +395,7 @@ func renderRevisionPage(ctx *context.Context) (*git.Repository, *git.TreeEntry)
 	// get Commit Count
 	commitsHistory, err := wikiRepo.CommitsByFileAndRange(
 		git.CommitsByFileAndRangeOptions{
-			Revision: wiki_service.DefaultBranch,
+			Revision: ctx.Repo.Repository.DefaultWikiBranch,
 			File:     pageFilename,
 			Page:     page,
 		})
@@ -402,20 +417,17 @@ func renderRevisionPage(ctx *context.Context) (*git.Repository, *git.TreeEntry)
 
 func renderEditPage(ctx *context.Context) {
 	wikiRepo, commit, err := findWikiRepoCommit(ctx)
-	if err != nil {
+	defer func() {
 		if wikiRepo != nil {
-			wikiRepo.Close()
+			_ = wikiRepo.Close()
 		}
+	}()
+	if err != nil {
 		if !git.IsErrNotExist(err) {
 			ctx.ServerError("GetBranchCommit", err)
 		}
 		return
 	}
-	defer func() {
-		if wikiRepo != nil {
-			wikiRepo.Close()
-		}
-	}()
 
 	// get requested pagename
 	pageName := wiki_service.WebPathFromRequest(ctx.PathParamRaw("*"))
@@ -584,17 +596,15 @@ func WikiPages(ctx *context.Context) {
 	ctx.Data["CanWriteWiki"] = ctx.Repo.CanWrite(unit.TypeWiki) && !ctx.Repo.Repository.IsArchived
 
 	wikiRepo, commit, err := findWikiRepoCommit(ctx)
-	if err != nil {
-		if wikiRepo != nil {
-			wikiRepo.Close()
-		}
-		return
-	}
 	defer func() {
 		if wikiRepo != nil {
-			wikiRepo.Close()
+			_ = wikiRepo.Close()
 		}
 	}()
+	if err != nil {
+		ctx.Redirect(ctx.Repo.RepoLink + "/wiki")
+		return
+	}
 
 	entries, err := commit.ListEntries()
 	if err != nil {
diff --git a/routers/web/repo/wiki_test.go b/routers/web/repo/wiki_test.go
index 719cca3049..52e216e6a0 100644
--- a/routers/web/repo/wiki_test.go
+++ b/routers/web/repo/wiki_test.go
@@ -9,6 +9,7 @@ import (
 	"net/url"
 	"testing"
 
+	"code.gitea.io/gitea/models/db"
 	repo_model "code.gitea.io/gitea/models/repo"
 	"code.gitea.io/gitea/models/unittest"
 	"code.gitea.io/gitea/modules/git"
@@ -221,3 +222,32 @@ func TestWikiRaw(t *testing.T) {
 		}
 	}
 }
+
+func TestDefaultWikiBranch(t *testing.T) {
+	unittest.PrepareTestEnv(t)
+
+	assert.NoError(t, repo_model.UpdateRepositoryCols(db.DefaultContext, &repo_model.Repository{ID: 1, DefaultWikiBranch: "wrong-branch"}))
+
+	ctx, _ := contexttest.MockContext(t, "user2/repo1/wiki")
+	ctx.SetParams("*", "Home")
+	contexttest.LoadRepo(t, ctx, 1)
+	assert.Equal(t, "wrong-branch", ctx.Repo.Repository.DefaultWikiBranch)
+	Wiki(ctx) // after the visiting, the out-of-sync database record will update the branch name to "master"
+	repo := unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{ID: 1})
+	assert.Equal(t, "master", ctx.Repo.Repository.DefaultWikiBranch)
+
+	// invalid branch name should fail
+	assert.Error(t, wiki_service.ChangeDefaultWikiBranch(db.DefaultContext, repo, "the bad name"))
+	repo = unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{ID: 1})
+	assert.Equal(t, "master", repo.DefaultWikiBranch)
+
+	// the same branch name, should succeed (actually a no-op)
+	assert.NoError(t, wiki_service.ChangeDefaultWikiBranch(db.DefaultContext, repo, "master"))
+	repo = unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{ID: 1})
+	assert.Equal(t, "master", repo.DefaultWikiBranch)
+
+	// change to another name
+	assert.NoError(t, wiki_service.ChangeDefaultWikiBranch(db.DefaultContext, repo, "main"))
+	repo = unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{ID: 1})
+	assert.Equal(t, "main", repo.DefaultWikiBranch)
+}
diff --git a/services/forms/repo_form.go b/services/forms/repo_form.go
index 8c3e458d2f..e45a2a1695 100644
--- a/services/forms/repo_form.go
+++ b/services/forms/repo_form.go
@@ -133,6 +133,7 @@ type RepoSettingForm struct {
 	EnableCode                            bool
 	EnableWiki                            bool
 	EnableExternalWiki                    bool
+	DefaultWikiBranch                     string
 	ExternalWikiURL                       string
 	EnableIssues                          bool
 	EnableExternalTracker                 bool
diff --git a/services/repository/create.go b/services/repository/create.go
index c47ce9c413..8d8c39197d 100644
--- a/services/repository/create.go
+++ b/services/repository/create.go
@@ -173,6 +173,7 @@ func initRepository(ctx context.Context, repoPath string, u *user_model.User, re
 	}
 
 	repo.DefaultBranch = setting.Repository.DefaultBranch
+	repo.DefaultWikiBranch = setting.Repository.DefaultBranch
 
 	if len(opts.DefaultBranch) > 0 {
 		repo.DefaultBranch = opts.DefaultBranch
@@ -240,6 +241,7 @@ func CreateRepositoryDirectly(ctx context.Context, doer, u *user_model.User, opt
 		TrustModel:                      opts.TrustModel,
 		IsMirror:                        opts.IsMirror,
 		DefaultBranch:                   opts.DefaultBranch,
+		DefaultWikiBranch:               setting.Repository.DefaultBranch,
 		ObjectFormatName:                opts.ObjectFormatName,
 	}
 
diff --git a/services/repository/migrate.go b/services/repository/migrate.go
index 51fdd90f54..aae2ddc120 100644
--- a/services/repository/migrate.go
+++ b/services/repository/migrate.go
@@ -25,6 +25,54 @@ import (
 	"code.gitea.io/gitea/modules/util"
 )
 
+func cloneWiki(ctx context.Context, u *user_model.User, opts migration.MigrateOptions, migrateTimeout time.Duration) (string, error) {
+	wikiPath := repo_model.WikiPath(u.Name, opts.RepoName)
+	wikiRemotePath := repo_module.WikiRemoteURL(ctx, opts.CloneAddr)
+	if wikiRemotePath == "" {
+		return "", nil
+	}
+
+	if err := util.RemoveAll(wikiPath); err != nil {
+		return "", fmt.Errorf("failed to remove existing wiki dir %q, err: %w", wikiPath, err)
+	}
+
+	cleanIncompleteWikiPath := func() {
+		if err := util.RemoveAll(wikiPath); err != nil {
+			log.Error("Failed to remove incomplete wiki dir %q, err: %v", wikiPath, err)
+		}
+	}
+	if err := git.Clone(ctx, wikiRemotePath, wikiPath, git.CloneRepoOptions{
+		Mirror:        true,
+		Quiet:         true,
+		Timeout:       migrateTimeout,
+		SkipTLSVerify: setting.Migrations.SkipTLSVerify,
+	}); err != nil {
+		log.Error("Clone wiki failed, err: %v", err)
+		cleanIncompleteWikiPath()
+		return "", err
+	}
+
+	if err := git.WriteCommitGraph(ctx, wikiPath); err != nil {
+		cleanIncompleteWikiPath()
+		return "", err
+	}
+
+	wikiRepo, err := git.OpenRepository(ctx, wikiPath)
+	if err != nil {
+		cleanIncompleteWikiPath()
+		return "", fmt.Errorf("failed to open wiki repo %q, err: %w", wikiPath, err)
+	}
+	defer wikiRepo.Close()
+
+	defaultBranch, err := wikiRepo.GetDefaultBranch()
+	if err != nil {
+		cleanIncompleteWikiPath()
+		return "", fmt.Errorf("failed to get wiki repo default branch for %q, err: %w", wikiPath, err)
+	}
+
+	return defaultBranch, nil
+}
+
 // MigrateRepositoryGitData starts migrating git related data after created migrating repository
 func MigrateRepositoryGitData(ctx context.Context, u *user_model.User,
 	repo *repo_model.Repository, opts migration.MigrateOptions,
@@ -44,21 +92,20 @@ func MigrateRepositoryGitData(ctx context.Context, u *user_model.User,
 
 	migrateTimeout := time.Duration(setting.Git.Timeout.Migrate) * time.Second
 
-	var err error
-	if err = util.RemoveAll(repoPath); err != nil {
-		return repo, fmt.Errorf("Failed to remove %s: %w", repoPath, err)
+	if err := util.RemoveAll(repoPath); err != nil {
+		return repo, fmt.Errorf("failed to remove existing repo dir %q, err: %w", repoPath, err)
 	}
 
-	if err = git.Clone(ctx, opts.CloneAddr, repoPath, git.CloneRepoOptions{
+	if err := git.Clone(ctx, opts.CloneAddr, repoPath, git.CloneRepoOptions{
 		Mirror:        true,
 		Quiet:         true,
 		Timeout:       migrateTimeout,
 		SkipTLSVerify: setting.Migrations.SkipTLSVerify,
 	}); err != nil {
 		if errors.Is(err, context.DeadlineExceeded) {
-			return repo, fmt.Errorf("Clone timed out. Consider increasing [git.timeout] MIGRATE in app.ini. Underlying Error: %w", err)
+			return repo, fmt.Errorf("clone timed out, consider increasing [git.timeout] MIGRATE in app.ini, underlying err: %w", err)
 		}
-		return repo, fmt.Errorf("Clone: %w", err)
+		return repo, fmt.Errorf("clone error: %w", err)
 	}
 
 	if err := git.WriteCommitGraph(ctx, repoPath); err != nil {
@@ -66,37 +113,18 @@ func MigrateRepositoryGitData(ctx context.Context, u *user_model.User,
 	}
 
 	if opts.Wiki {
-		wikiPath := repo_model.WikiPath(u.Name, opts.RepoName)
-		wikiRemotePath := repo_module.WikiRemoteURL(ctx, opts.CloneAddr)
-		if len(wikiRemotePath) > 0 {
-			if err := util.RemoveAll(wikiPath); err != nil {
-				return repo, fmt.Errorf("Failed to remove %s: %w", wikiPath, err)
-			}
-
-			if err := git.Clone(ctx, wikiRemotePath, wikiPath, git.CloneRepoOptions{
-				Mirror:        true,
-				Quiet:         true,
-				Timeout:       migrateTimeout,
-				Branch:        "master",
-				SkipTLSVerify: setting.Migrations.SkipTLSVerify,
-			}); err != nil {
-				log.Warn("Clone wiki: %v", err)
-				if err := util.RemoveAll(wikiPath); err != nil {
-					return repo, fmt.Errorf("Failed to remove %s: %w", wikiPath, err)
-				}
-			} else {
-				if err := git.WriteCommitGraph(ctx, wikiPath); err != nil {
-					return repo, err
-				}
-			}
+		defaultWikiBranch, err := cloneWiki(ctx, u, opts, migrateTimeout)
+		if err != nil {
+			return repo, fmt.Errorf("clone wiki error: %w", err)
 		}
+		repo.DefaultWikiBranch = defaultWikiBranch
 	}
 
 	if repo.OwnerID == u.ID {
 		repo.Owner = u
 	}
 
-	if err = repo_module.CheckDaemonExportOK(ctx, repo); err != nil {
+	if err := repo_module.CheckDaemonExportOK(ctx, repo); err != nil {
 		return repo, fmt.Errorf("checkDaemonExportOK: %w", err)
 	}
 
diff --git a/services/wiki/wiki.go b/services/wiki/wiki.go
index 50d52d3140..6f1ca120b0 100644
--- a/services/wiki/wiki.go
+++ b/services/wiki/wiki.go
@@ -6,18 +6,22 @@ package wiki
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"os"
 	"strings"
 
+	"code.gitea.io/gitea/models/db"
 	repo_model "code.gitea.io/gitea/models/repo"
 	system_model "code.gitea.io/gitea/models/system"
 	"code.gitea.io/gitea/models/unit"
 	user_model "code.gitea.io/gitea/models/user"
 	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/gitrepo"
 	"code.gitea.io/gitea/modules/log"
 	repo_module "code.gitea.io/gitea/modules/repository"
 	"code.gitea.io/gitea/modules/sync"
+	"code.gitea.io/gitea/modules/util"
 	asymkey_service "code.gitea.io/gitea/services/asymkey"
 	repo_service "code.gitea.io/gitea/services/repository"
 )
@@ -25,10 +29,7 @@ import (
 // TODO: use clustered lock (unique queue? or *abuse* cache)
 var wikiWorkingPool = sync.NewExclusivePool()
 
-const (
-	DefaultRemote = "origin"
-	DefaultBranch = "master"
-)
+const DefaultRemote = "origin"
 
 // InitWiki initializes a wiki for repository,
 // it does nothing when repository already has wiki.
@@ -41,25 +42,25 @@ func InitWiki(ctx context.Context, repo *repo_model.Repository) error {
 		return fmt.Errorf("InitRepository: %w", err)
 	} else if err = repo_module.CreateDelegateHooks(repo.WikiPath()); err != nil {
 		return fmt.Errorf("createDelegateHooks: %w", err)
-	} else if _, _, err = git.NewCommand(ctx, "symbolic-ref", "HEAD", git.BranchPrefix+DefaultBranch).RunStdString(&git.RunOpts{Dir: repo.WikiPath()}); err != nil {
-		return fmt.Errorf("unable to set default wiki branch to master: %w", err)
+	} else if _, _, err = git.NewCommand(ctx, "symbolic-ref", "HEAD").AddDynamicArguments(git.BranchPrefix + repo.DefaultWikiBranch).RunStdString(&git.RunOpts{Dir: repo.WikiPath()}); err != nil {
+		return fmt.Errorf("unable to set default wiki branch to %q: %w", repo.DefaultWikiBranch, err)
 	}
 	return nil
 }
 
 // prepareGitPath try to find a suitable file path with file name by the given raw wiki name.
 // return: existence, prepared file path with name, error
-func prepareGitPath(gitRepo *git.Repository, wikiPath WebPath) (bool, string, error) {
+func prepareGitPath(gitRepo *git.Repository, defaultWikiBranch string, wikiPath WebPath) (bool, string, error) {
 	unescaped := string(wikiPath) + ".md"
 	gitPath := WebPathToGitPath(wikiPath)
 
 	// Look for both files
-	filesInIndex, err := gitRepo.LsTree(DefaultBranch, unescaped, gitPath)
+	filesInIndex, err := gitRepo.LsTree(defaultWikiBranch, unescaped, gitPath)
 	if err != nil {
-		if strings.Contains(err.Error(), "Not a valid object name master") {
-			return false, gitPath, nil
+		if strings.Contains(err.Error(), "Not a valid object name") {
+			return false, gitPath, nil // branch doesn't exist
 		}
-		log.Error("%v", err)
+		log.Error("Wiki LsTree failed, err: %v", err)
 		return false, gitPath, err
 	}
 
@@ -95,7 +96,7 @@ func updateWikiPage(ctx context.Context, doer *user_model.User, repo *repo_model
 		return fmt.Errorf("InitWiki: %w", err)
 	}
 
-	hasMasterBranch := git.IsBranchExist(ctx, repo.WikiPath(), DefaultBranch)
+	hasDefaultBranch := git.IsBranchExist(ctx, repo.WikiPath(), repo.DefaultWikiBranch)
 
 	basePath, err := repo_module.CreateTemporaryPath("update-wiki")
 	if err != nil {
@@ -112,8 +113,8 @@ func updateWikiPage(ctx context.Context, doer *user_model.User, repo *repo_model
 		Shared: true,
 	}
 
-	if hasMasterBranch {
-		cloneOpts.Branch = DefaultBranch
+	if hasDefaultBranch {
+		cloneOpts.Branch = repo.DefaultWikiBranch
 	}
 
 	if err := git.Clone(ctx, repo.WikiPath(), basePath, cloneOpts); err != nil {
@@ -128,14 +129,14 @@ func updateWikiPage(ctx context.Context, doer *user_model.User, repo *repo_model
 	}
 	defer gitRepo.Close()
 
-	if hasMasterBranch {
+	if hasDefaultBranch {
 		if err := gitRepo.ReadTreeToIndex("HEAD"); err != nil {
 			log.Error("Unable to read HEAD tree to index in: %s %v", basePath, err)
 			return fmt.Errorf("fnable to read HEAD tree to index in: %s %w", basePath, err)
 		}
 	}
 
-	isWikiExist, newWikiPath, err := prepareGitPath(gitRepo, newWikiName)
+	isWikiExist, newWikiPath, err := prepareGitPath(gitRepo, repo.DefaultWikiBranch, newWikiName)
 	if err != nil {
 		return err
 	}
@@ -151,7 +152,7 @@ func updateWikiPage(ctx context.Context, doer *user_model.User, repo *repo_model
 		isOldWikiExist := true
 		oldWikiPath := newWikiPath
 		if oldWikiName != newWikiName {
-			isOldWikiExist, oldWikiPath, err = prepareGitPath(gitRepo, oldWikiName)
+			isOldWikiExist, oldWikiPath, err = prepareGitPath(gitRepo, repo.DefaultWikiBranch, oldWikiName)
 			if err != nil {
 				return err
 			}
@@ -200,7 +201,7 @@ func updateWikiPage(ctx context.Context, doer *user_model.User, repo *repo_model
 	} else {
 		commitTreeOpts.NoGPGSign = true
 	}
-	if hasMasterBranch {
+	if hasDefaultBranch {
 		commitTreeOpts.Parents = []string{"HEAD"}
 	}
 
@@ -212,7 +213,7 @@ func updateWikiPage(ctx context.Context, doer *user_model.User, repo *repo_model
 
 	if err := git.Push(gitRepo.Ctx, basePath, git.PushOptions{
 		Remote: DefaultRemote,
-		Branch: fmt.Sprintf("%s:%s%s", commitHash.String(), git.BranchPrefix, DefaultBranch),
+		Branch: fmt.Sprintf("%s:%s%s", commitHash.String(), git.BranchPrefix, repo.DefaultWikiBranch),
 		Env: repo_module.FullPushingEnvironment(
 			doer,
 			doer,
@@ -269,7 +270,7 @@ func DeleteWikiPage(ctx context.Context, doer *user_model.User, repo *repo_model
 	if err := git.Clone(ctx, repo.WikiPath(), basePath, git.CloneRepoOptions{
 		Bare:   true,
 		Shared: true,
-		Branch: DefaultBranch,
+		Branch: repo.DefaultWikiBranch,
 	}); err != nil {
 		log.Error("Failed to clone repository: %s (%v)", repo.FullName(), err)
 		return fmt.Errorf("failed to clone repository: %s (%w)", repo.FullName(), err)
@@ -287,7 +288,7 @@ func DeleteWikiPage(ctx context.Context, doer *user_model.User, repo *repo_model
 		return fmt.Errorf("unable to read HEAD tree to index in: %s %w", basePath, err)
 	}
 
-	found, wikiPath, err := prepareGitPath(gitRepo, wikiName)
+	found, wikiPath, err := prepareGitPath(gitRepo, repo.DefaultWikiBranch, wikiName)
 	if err != nil {
 		return err
 	}
@@ -331,7 +332,7 @@ func DeleteWikiPage(ctx context.Context, doer *user_model.User, repo *repo_model
 
 	if err := git.Push(gitRepo.Ctx, basePath, git.PushOptions{
 		Remote: DefaultRemote,
-		Branch: fmt.Sprintf("%s:%s%s", commitHash.String(), git.BranchPrefix, DefaultBranch),
+		Branch: fmt.Sprintf("%s:%s%s", commitHash.String(), git.BranchPrefix, repo.DefaultWikiBranch),
 		Env: repo_module.FullPushingEnvironment(
 			doer,
 			doer,
@@ -358,3 +359,37 @@ func DeleteWiki(ctx context.Context, repo *repo_model.Repository) error {
 	system_model.RemoveAllWithNotice(ctx, "Delete repository wiki", repo.WikiPath())
 	return nil
 }
+
+func ChangeDefaultWikiBranch(ctx context.Context, repo *repo_model.Repository, newBranch string) error {
+	if !git.IsValidRefPattern(newBranch) {
+		return fmt.Errorf("invalid branch name: %s", newBranch)
+	}
+	return db.WithTx(ctx, func(ctx context.Context) error {
+		repo.DefaultWikiBranch = newBranch
+		if err := repo_model.UpdateRepositoryCols(ctx, repo, "default_wiki_branch"); err != nil {
+			return fmt.Errorf("unable to update database: %w", err)
+		}
+
+		gitRepo, err := gitrepo.OpenWikiRepository(ctx, repo)
+		if errors.Is(err, util.ErrNotExist) {
+			return nil // no git repo on storage, no need to do anything else
+		} else if err != nil {
+			return fmt.Errorf("unable to open repository: %w", err)
+		}
+		defer gitRepo.Close()
+
+		oldDefBranch, err := gitRepo.GetDefaultBranch()
+		if err != nil {
+			return fmt.Errorf("unable to get default branch: %w", err)
+		}
+		if oldDefBranch == newBranch {
+			return nil
+		}
+
+		err = gitRepo.RenameBranch(oldDefBranch, newBranch)
+		if err != nil {
+			return fmt.Errorf("unable to rename default branch: %w", err)
+		}
+		return nil
+	})
+}
diff --git a/services/wiki/wiki_test.go b/services/wiki/wiki_test.go
index 59c77060f2..0a18cffa25 100644
--- a/services/wiki/wiki_test.go
+++ b/services/wiki/wiki_test.go
@@ -170,7 +170,7 @@ func TestRepository_AddWikiPage(t *testing.T) {
 				return
 			}
 			defer gitRepo.Close()
-			masterTree, err := gitRepo.GetTree(DefaultBranch)
+			masterTree, err := gitRepo.GetTree(repo.DefaultWikiBranch)
 			assert.NoError(t, err)
 			gitPath := WebPathToGitPath(webPath)
 			entry, err := masterTree.GetTreeEntryByPath(gitPath)
@@ -215,7 +215,7 @@ func TestRepository_EditWikiPage(t *testing.T) {
 		// Now need to show that the page has been added:
 		gitRepo, err := gitrepo.OpenWikiRepository(git.DefaultContext, repo)
 		assert.NoError(t, err)
-		masterTree, err := gitRepo.GetTree(DefaultBranch)
+		masterTree, err := gitRepo.GetTree(repo.DefaultWikiBranch)
 		assert.NoError(t, err)
 		gitPath := WebPathToGitPath(webPath)
 		entry, err := masterTree.GetTreeEntryByPath(gitPath)
@@ -242,7 +242,7 @@ func TestRepository_DeleteWikiPage(t *testing.T) {
 		return
 	}
 	defer gitRepo.Close()
-	masterTree, err := gitRepo.GetTree(DefaultBranch)
+	masterTree, err := gitRepo.GetTree(repo.DefaultWikiBranch)
 	assert.NoError(t, err)
 	gitPath := WebPathToGitPath("Home")
 	_, err = masterTree.GetTreeEntryByPath(gitPath)
@@ -280,7 +280,7 @@ func TestPrepareWikiFileName(t *testing.T) {
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			webPath := UserTitleToWebPath("", tt.arg)
-			existence, newWikiPath, err := prepareGitPath(gitRepo, webPath)
+			existence, newWikiPath, err := prepareGitPath(gitRepo, repo.DefaultWikiBranch, webPath)
 			if (err != nil) != tt.wantErr {
 				assert.NoError(t, err)
 				return
@@ -312,7 +312,7 @@ func TestPrepareWikiFileName_FirstPage(t *testing.T) {
 	}
 	defer gitRepo.Close()
 
-	existence, newWikiPath, err := prepareGitPath(gitRepo, "Home")
+	existence, newWikiPath, err := prepareGitPath(gitRepo, "master", "Home")
 	assert.False(t, existence)
 	assert.NoError(t, err)
 	assert.EqualValues(t, "Home.md", newWikiPath)
diff --git a/templates/repo/settings/options.tmpl b/templates/repo/settings/options.tmpl
index 0de42b34ea..a699396a84 100644
--- a/templates/repo/settings/options.tmpl
+++ b/templates/repo/settings/options.tmpl
@@ -335,6 +335,10 @@
 							<label>{{ctx.Locale.Tr "repo.settings.use_internal_wiki"}}</label>
 						</div>
 					</div>
+					<div class="inline field gt-pl-4">
+						<label>{{ctx.Locale.Tr "repo.settings.default_wiki_branch_name"}}</label>
+						<input name="default_wiki_branch" value="{{.Repository.DefaultWikiBranch}}">
+					</div>
 					<div class="field">
 						<div class="ui radio checkbox{{if $isExternalWikiGlobalDisabled}} disabled{{end}}"{{if $isExternalWikiGlobalDisabled}} data-tooltip-content="{{ctx.Locale.Tr "repo.unit_disabled"}}"{{end}}>
 							<input class="enable-system-radio" name="enable_external_wiki" type="radio" value="true" data-target="#external_wiki_box" {{if .Repository.UnitEnabled $.Context $.UnitTypeExternalWiki}}checked{{end}}>
diff --git a/templates/repo/wiki/new.tmpl b/templates/repo/wiki/new.tmpl
index ff31df0c32..640f8ca9cd 100644
--- a/templates/repo/wiki/new.tmpl
+++ b/templates/repo/wiki/new.tmpl
@@ -36,9 +36,8 @@
 			</div>
 			<div class="divider"></div>
 			<div class="text right">
-				<button class="ui primary button">
-					{{ctx.Locale.Tr "repo.wiki.save_page"}}
-				</button>
+				<a class="ui basic cancel button" href="{{.Link}}">{{ctx.Locale.Tr "cancel"}}</a>
+				<button class="ui primary button">{{ctx.Locale.Tr "repo.wiki.save_page"}}</button>
 			</div>
 		</form>
 	</div>
diff --git a/templates/repo/wiki/pages.tmpl b/templates/repo/wiki/pages.tmpl
index 22eb2619f9..cace0d48e0 100644
--- a/templates/repo/wiki/pages.tmpl
+++ b/templates/repo/wiki/pages.tmpl
@@ -10,6 +10,7 @@
 				{{end}}
 			</span>
 		</h2>
+		{{if .IsRepositoryAdmin}}<div>{{ctx.Locale.Tr "repo.default_branch"}}: {{.Repository.DefaultWikiBranch}}</div>{{end}}
 		<table class="ui table wiki-pages-list">
 			<tbody>
 				{{range .Pages}}