Use frontend fetch for branch dropdown component (#25719)

- Send request to get branch/tag list, use loading icon when waiting for
response.
- Only fetch when the first time branch/tag list shows.
- For backend, removed assignment to `ctx.Data["Branches"]` and
`ctx.Data["Tags"]` from `context/repo.go` and passed these data wherever
needed.
- Changed some `v-if` to `v-show` and used native `svg` as mentioned in
#25719 (comment) to
improve perfomance when there are a lot of branches.
- Places Used the dropdown component:

     Repo Home Page
    
<img width="1429" alt="Screen Shot 2023-07-06 at 12 17 51"
src="https://github.com/go-gitea/gitea/assets/17645053/6accc7b6-8d37-4e88-ae1a-bd2b3b927ea0">

    Commits Page

<img width="1431" alt="Screen Shot 2023-07-06 at 12 18 34"
src="https://github.com/go-gitea/gitea/assets/17645053/2d0bf306-d1e2-45a8-a784-bc424879f537">

    Specific commit -> operations -> cherry-pick
    
<img width="758" alt="Screen Shot 2023-07-06 at 12 23 28"
src="https://github.com/go-gitea/gitea/assets/17645053/1e557948-3881-4e45-a625-8ef36d45ae2d">

    Release Page
    
<img width="1433" alt="Screen Shot 2023-07-06 at 12 25 05"
src="https://github.com/go-gitea/gitea/assets/17645053/3ec82af1-15a4-4162-a50b-04a9502161bb">

- Demo


https://github.com/go-gitea/gitea/assets/17645053/d45d266b-3eb0-465a-82f9-57f78dc5f9f3

- Note:

UI of dropdown menu could be improved in another PR as it should apply
to more dropdown menus.

Fix #14180

---------

Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

modules/context/repo.go

@@ -660,13 +660,6 @@ func RepoAssignment(ctx *Context) context.CancelFunc {
 		return cancel
 	}
 
-	tags, err := repo_model.GetTagNamesByRepoID(ctx, ctx.Repo.Repository.ID)
-	if err != nil {
-		ctx.ServerError("GetTagNamesByRepoID", err)
-		return cancel
-	}
-	ctx.Data["Tags"] = tags
-
 	branchOpts := git_model.FindBranchOptions{
 		RepoID:          ctx.Repo.Repository.ID,
 		IsDeletedBranch: util.OptionalBoolFalse,
@@ -680,7 +673,7 @@ func RepoAssignment(ctx *Context) context.CancelFunc {
 		return cancel
 	}
 
-	// non empty repo should have at least 1 branch, so this repository's branches haven't been synced yet
+	// non-empty repo should have at least 1 branch, so this repository's branches haven't been synced yet
 	if branchesTotal == 0 { // fallback to do a sync immediately
 		branchesTotal, err = repo_module.SyncRepoBranches(ctx, ctx.Repo.Repository.ID, 0)
 		if err != nil {
@@ -689,24 +682,19 @@ func RepoAssignment(ctx *Context) context.CancelFunc {
 		}
 	}
 
-	// FIXME: use paganation and async loading
-	branchOpts.ExcludeBranchNames = []string{ctx.Repo.Repository.DefaultBranch}
-	brs, err := git_model.FindBranchNames(ctx, branchOpts)
-	if err != nil {
-		ctx.ServerError("GetBranches", err)
-		return cancel
-	}
-	// always put default branch on the top
-	ctx.Data["Branches"] = append(branchOpts.ExcludeBranchNames, brs...)
 	ctx.Data["BranchesCount"] = branchesTotal
 
-	// If not branch selected, try default one.
-	// If default branch doesn't exist, fall back to some other branch.
+	// If no branch is set in the request URL, try to guess a default one.
 	if len(ctx.Repo.BranchName) == 0 {
 		if len(ctx.Repo.Repository.DefaultBranch) > 0 && gitRepo.IsBranchExist(ctx.Repo.Repository.DefaultBranch) {
 			ctx.Repo.BranchName = ctx.Repo.Repository.DefaultBranch
-		} else if len(brs) > 0 {
-			ctx.Repo.BranchName = brs[0]
+		} else {
+			ctx.Repo.BranchName, _ = gitRepo.GetDefaultBranch()
+			if ctx.Repo.BranchName == "" {
+				// If it still can't get a default branch, fall back to default branch from setting.
+				// Something might be wrong. Either site admin should fix the repo sync or Gitea should fix a potential bug.
+				ctx.Repo.BranchName = setting.Repository.DefaultBranch
+			}
 		}
 		ctx.Repo.RefName = ctx.Repo.BranchName
 	}

routers/web/repo/compare.go

@@ -754,6 +754,12 @@ func CompareDiff(ctx *context.Context) {
 	}
 	ctx.Data["HeadBranches"] = headBranches
 
+	// For compare repo branches
+	PrepareBranchList(ctx)
+	if ctx.Written() {
+		return
+	}
+
 	headTags, err := repo_model.GetTagNamesByRepoID(ctx, ci.HeadRepo.ID)
 	if err != nil {
 		ctx.ServerError("GetTagNamesByRepoID", err)

routers/web/repo/issue.go

@@ -785,18 +785,10 @@ func RetrieveRepoMetas(ctx *context.Context, repo *repo_model.Repository, isPull
 		return nil
 	}
 
-	brs, err := git_model.FindBranchNames(ctx, git_model.FindBranchOptions{
-		RepoID: ctx.Repo.Repository.ID,
-		ListOptions: db.ListOptions{
-			ListAll: true,
-		},
-		IsDeletedBranch: util.OptionalBoolFalse,
-	})
-	if err != nil {
-		ctx.ServerError("GetBranches", err)
+	PrepareBranchList(ctx)
+	if ctx.Written() {
 		return nil
 	}
-	ctx.Data["Branches"] = brs
 
 	// Contains true if the user can create issue dependencies
 	ctx.Data["CanCreateIssueDependencies"] = ctx.Repo.CanCreateIssueDependencies(ctx.Doer, isPull)
@@ -921,6 +913,13 @@ func NewIssue(ctx *context.Context) {
 
 	RetrieveRepoMetas(ctx, ctx.Repo.Repository, false)
 
+	tags, err := repo_model.GetTagNamesByRepoID(ctx, ctx.Repo.Repository.ID)
+	if err != nil {
+		ctx.ServerError("GetTagNamesByRepoID", err)
+		return
+	}
+	ctx.Data["Tags"] = tags
+
 	_, templateErrs := issue_service.GetTemplatesFromDefaultBranch(ctx.Repo.Repository, ctx.Repo.GitRepo)
 	if errs := setTemplateIfExists(ctx, issueTemplateKey, IssueTemplateCandidates); len(errs) > 0 {
 		for k, v := range errs {
@@ -1918,6 +1917,19 @@ func ViewIssue(ctx *context.Context) {
 	ctx.Data["ShouldShowCommentType"] = func(commentType issues_model.CommentType) bool {
 		return hiddenCommentTypes == nil || hiddenCommentTypes.Bit(int(commentType)) == 0
 	}
+	// For sidebar
+	PrepareBranchList(ctx)
+
+	if ctx.Written() {
+		return
+	}
+
+	tags, err := repo_model.GetTagNamesByRepoID(ctx, ctx.Repo.Repository.ID)
+	if err != nil {
+		ctx.ServerError("GetTagNamesByRepoID", err)
+		return
+	}
+	ctx.Data["Tags"] = tags
 
 	ctx.HTML(http.StatusOK, tplIssueView)
 }

routers/web/repo/pull.go

@@ -729,6 +729,11 @@ func ViewPullCommits(ctx *context.Context) {
 	ctx.Data["HasIssuesOrPullsWritePermission"] = ctx.Repo.CanWriteIssuesOrPulls(issue.IsPull)
 	ctx.Data["IsIssuePoster"] = ctx.IsSigned && issue.IsPoster(ctx.Doer.ID)
 
+	// For PR commits page
+	PrepareBranchList(ctx)
+	if ctx.Written() {
+		return
+	}
 	getBranchData(ctx, issue)
 	ctx.HTML(http.StatusOK, tplPullCommits)
 }
@@ -893,6 +898,11 @@ func ViewPullFiles(ctx *context.Context) {
 	ctx.Data["HasIssuesOrPullsWritePermission"] = ctx.Repo.CanWriteIssuesOrPulls(issue.IsPull)
 
 	ctx.Data["IsAttachmentEnabled"] = setting.Attachment.Enabled
+	// For files changed page
+	PrepareBranchList(ctx)
+	if ctx.Written() {
+		return
+	}
 	upload.AddUploadContext(ctx, "comment")
 
 	ctx.HTML(http.StatusOK, tplPullFiles)

routers/web/repo/release.go

@@ -352,6 +352,20 @@ func NewRelease(ctx *context.Context) {
 	ctx.Data["Assignees"] = MakeSelfOnTop(ctx, assigneeUsers)
 
 	upload.AddUploadContext(ctx, "release")
+
+	// For New Release page
+	PrepareBranchList(ctx)
+	if ctx.Written() {
+		return
+	}
+
+	tags, err := repo_model.GetTagNamesByRepoID(ctx, ctx.Repo.Repository.ID)
+	if err != nil {
+		ctx.ServerError("GetTagNamesByRepoID", err)
+		return
+	}
+	ctx.Data["Tags"] = tags
+
 	ctx.HTML(http.StatusOK, tplReleaseNew)
 }
 
@@ -361,6 +375,13 @@ func NewReleasePost(ctx *context.Context) {
 	ctx.Data["Title"] = ctx.Tr("repo.release.new_release")
 	ctx.Data["PageIsReleaseList"] = true
 
+	tags, err := repo_model.GetTagNamesByRepoID(ctx, ctx.Repo.Repository.ID)
+	if err != nil {
+		ctx.ServerError("GetTagNamesByRepoID", err)
+		return
+	}
+	ctx.Data["Tags"] = tags
+
 	if ctx.HasError() {
 		ctx.HTML(http.StatusOK, tplReleaseNew)
 		return

routers/web/repo/repo.go

@@ -622,3 +622,64 @@ func SearchRepo(ctx *context.Context) {
 		Data: results,
 	})
 }
+
+type branchTagSearchResponse struct {
+	Results []string `json:"results"`
+}
+
+// GetBranchesList get branches for current repo'
+func GetBranchesList(ctx *context.Context) {
+	branchOpts := git_model.FindBranchOptions{
+		RepoID:          ctx.Repo.Repository.ID,
+		IsDeletedBranch: util.OptionalBoolFalse,
+		ListOptions: db.ListOptions{
+			ListAll: true,
+		},
+	}
+	branches, err := git_model.FindBranchNames(ctx, branchOpts)
+	if err != nil {
+		ctx.JSON(http.StatusInternalServerError, err)
+		return
+	}
+	resp := &branchTagSearchResponse{}
+	// always put default branch on the top if it exists
+	if util.SliceContains(branches, ctx.Repo.Repository.DefaultBranch) {
+		branches = util.SliceRemoveAll(branches, ctx.Repo.Repository.DefaultBranch)
+		branches = append([]string{ctx.Repo.Repository.DefaultBranch}, branches...)
+	}
+	resp.Results = branches
+	ctx.JSON(http.StatusOK, resp)
+}
+
+// GetTagList get tag list for current repo
+func GetTagList(ctx *context.Context) {
+	tags, err := repo_model.GetTagNamesByRepoID(ctx, ctx.Repo.Repository.ID)
+	if err != nil {
+		ctx.JSON(http.StatusInternalServerError, err)
+		return
+	}
+	resp := &branchTagSearchResponse{}
+	resp.Results = tags
+	ctx.JSON(http.StatusOK, resp)
+}
+
+func PrepareBranchList(ctx *context.Context) {
+	branchOpts := git_model.FindBranchOptions{
+		RepoID:          ctx.Repo.Repository.ID,
+		IsDeletedBranch: util.OptionalBoolFalse,
+		ListOptions: db.ListOptions{
+			ListAll: true,
+		},
+	}
+	brs, err := git_model.FindBranchNames(ctx, branchOpts)
+	if err != nil {
+		ctx.ServerError("GetBranches", err)
+		return
+	}
+	// always put default branch on the top if it exists
+	if util.SliceContains(brs, ctx.Repo.Repository.DefaultBranch) {
+		brs = util.SliceRemoveAll(brs, ctx.Repo.Repository.DefaultBranch)
+		brs = append([]string{ctx.Repo.Repository.DefaultBranch}, brs...)
+	}
+	ctx.Data["Branches"] = brs
+}

routers/web/repo/setting/protected_branch.go

@@ -21,6 +21,7 @@ import (
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/web"
+	"code.gitea.io/gitea/routers/web/repo"
 	"code.gitea.io/gitea/services/forms"
 	pull_service "code.gitea.io/gitea/services/pull"
 	"code.gitea.io/gitea/services/repository"
@@ -44,6 +45,11 @@ func ProtectedBranchRules(ctx *context.Context) {
 	}
 	ctx.Data["ProtectedBranches"] = rules
 
+	repo.PrepareBranchList(ctx)
+	if ctx.Written() {
+		return
+	}
+
 	ctx.HTML(http.StatusOK, tplBranches)
 }
 
@@ -52,6 +58,11 @@ func SetDefaultBranchPost(ctx *context.Context) {
 	ctx.Data["Title"] = ctx.Tr("repo.settings.branches.update_default_branch")
 	ctx.Data["PageIsSettingsBranches"] = true
 
+	repo.PrepareBranchList(ctx)
+	if ctx.Written() {
+		return
+	}
+
 	repo := ctx.Repo.Repository
 
 	switch ctx.FormString("action") {

routers/web/web.go

@@ -1094,6 +1094,7 @@ func registerRoutes(m *web.Route) {
 		}, context.RepoRef(), canEnableEditor, context.RepoMustNotBeArchived())
 
 		m.Group("/branches", func() {
+			m.Get("/list", repo.GetBranchesList)
 			m.Group("/_new", func() {
 				m.Post("/branch/*", context.RepoRefByType(context.RepoRefBranch), repo.CreateBranch)
 				m.Post("/tag/*", context.RepoRefByType(context.RepoRefTag), repo.CreateBranch)
@@ -1108,6 +1109,7 @@ func registerRoutes(m *web.Route) {
 	m.Group("/{username}/{reponame}", func() {
 		m.Group("/tags", func() {
 			m.Get("", repo.TagsList)
+			m.Get("/list", repo.GetTagList)
 			m.Get(".rss", feedEnabled, repo.TagsListFeedRSS)
 			m.Get(".atom", feedEnabled, repo.TagsListFeedAtom)
 		}, ctxDataSet("EnableFeed", setting.Other.EnableFeed),

templates/repo/branch_dropdown.tmpl

@@ -44,8 +44,6 @@
 		'tagName': {{.root.TagName}},
 		'branchName': {{.root.BranchName}},
 		'noTag': {{.noTag}},
-		'branches': {{.root.Branches}},
-		'tags': {{.root.Tags}},
 		'defaultBranch': {{$defaultBranch}},
 		'enableFeed': {{.root.EnableFeed}},
 		'rssURLPrefix': '{{$.root.RepoLink}}/rss/branch/',

web_src/css/repo.css

@@ -3359,3 +3359,7 @@ tbody.commit-list {
   font-size: 18px;
   margin-left: 4px;
 }
+
+#cherry-pick-modal .scrolling.menu {
+  max-height: 200px;
+}