Editor preview support for external renderers (#23333)

Remove `[repository.editor] PREVIEWABLE_FILE_MODES` setting that seemed
like it was intended to support this but did not work. Instead, whenever
viewing a file shows a preview, also have a Preview tab in the file
editor.

Add new `/markup` web and API endpoints with `comment`, `gfm`,
`markdown` and new `file` mode that uses a file path to determine the
renderer.

Remove `/markdown` web endpoint but keep the API for backwards and
GitHub compatibility.

## ⚠️ BREAKING ⚠️

The `[repository.editor] PREVIEWABLE_FILE_MODES` setting was removed.
This setting served no practical purpose and was not working correctly.
Instead a preview tab is always shown in the file editor when supported.

---------

Co-authored-by: zeripath <art27@cantab.net>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

9 files changed, 259 insertions, 183 deletions

diff --git a/routers/api/v1/api.go b/routers/api/v1/api.go
index c3a875e737..8fd824640f 100644
--- a/routers/api/v1/api.go
+++ b/routers/api/v1/api.go
@@ -711,6 +711,7 @@ func Routes(ctx gocontext.Context) *web.Route {
 			})
 		}
 		m.Get("/signing-key.gpg", misc.SigningKey)
+		m.Post("/markup", bind(api.MarkupOption{}), misc.Markup)
 		m.Post("/markdown", bind(api.MarkdownOption{}), misc.Markdown)
 		m.Post("/markdown/raw", misc.MarkdownRaw)
 		m.Group("/settings", func() {
@@ -1034,6 +1035,7 @@ func Routes(ctx gocontext.Context) *web.Route {
 						Patch(reqToken(auth_model.AccessTokenScopeRepo), reqRepoWriter(unit.TypeIssues, unit.TypePullRequests), bind(api.EditLabelOption{}), repo.EditLabel).
 						Delete(reqToken(auth_model.AccessTokenScopeRepo), reqRepoWriter(unit.TypeIssues, unit.TypePullRequests), repo.DeleteLabel)
 				})
+				m.Post("/markup", reqToken(auth_model.AccessTokenScopeRepo), bind(api.MarkupOption{}), misc.Markup)
 				m.Post("/markdown", reqToken(auth_model.AccessTokenScopeRepo), bind(api.MarkdownOption{}), misc.Markdown)
 				m.Post("/markdown/raw", reqToken(auth_model.AccessTokenScopeRepo), misc.MarkdownRaw)
 				m.Group("/milestones", func() {
diff --git a/routers/api/v1/misc/markdown.go b/routers/api/v1/misc/markup.go
index 3ff42f08d6..93d5754444 100644
--- a/routers/api/v1/misc/markdown.go
+++ b/routers/api/v1/misc/markup.go
@@ -5,19 +5,45 @@ package misc
 
 import (
 	"net/http"
-	"strings"
 
 	"code.gitea.io/gitea/modules/context"
 	"code.gitea.io/gitea/modules/markup"
 	"code.gitea.io/gitea/modules/markup/markdown"
-	"code.gitea.io/gitea/modules/setting"
 	api "code.gitea.io/gitea/modules/structs"
-	"code.gitea.io/gitea/modules/util"
 	"code.gitea.io/gitea/modules/web"
-
-	"mvdan.cc/xurls/v2"
+	"code.gitea.io/gitea/routers/common"
 )
 
+// Markup render markup document to HTML
+func Markup(ctx *context.APIContext) {
+	// swagger:operation POST /markup miscellaneous renderMarkup
+	// ---
+	// summary: Render a markup document as HTML
+	// parameters:
+	// - name: body
+	//   in: body
+	//   schema:
+	//     "$ref": "#/definitions/MarkupOption"
+	// consumes:
+	// - application/json
+	// produces:
+	//     - text/html
+	// responses:
+	//   "200":
+	//     "$ref": "#/responses/MarkupRender"
+	//   "422":
+	//     "$ref": "#/responses/validationError"
+
+	form := web.GetForm(ctx).(*api.MarkupOption)
+
+	if ctx.HasAPIError() {
+		ctx.Error(http.StatusUnprocessableEntity, "", ctx.GetErrMsg())
+		return
+	}
+
+	common.RenderMarkup(ctx.Context, form.Mode, form.Text, form.Context, form.FilePath, form.Wiki)
+}
+
 // Markdown render markdown document to HTML
 func Markdown(ctx *context.APIContext) {
 	// swagger:operation POST /markdown miscellaneous renderMarkdown
@@ -45,55 +71,12 @@ func Markdown(ctx *context.APIContext) {
 		return
 	}
 
-	if len(form.Text) == 0 {
-		_, _ = ctx.Write([]byte(""))
-		return
+	mode := "markdown"
+	if form.Mode == "comment" || form.Mode == "gfm" {
+		mode = form.Mode
 	}
 
-	switch form.Mode {
-	case "comment":
-		fallthrough
-	case "gfm":
-		urlPrefix := form.Context
-		meta := map[string]string{}
-		if !strings.HasPrefix(setting.AppSubURL+"/", urlPrefix) {
-			// check if urlPrefix is already set to a URL
-			linkRegex, _ := xurls.StrictMatchingScheme("https?://")
-			m := linkRegex.FindStringIndex(urlPrefix)
-			if m == nil {
-				urlPrefix = util.URLJoin(setting.AppURL, form.Context)
-			}
-		}
-		if ctx.Repo != nil && ctx.Repo.Repository != nil {
-			// "gfm" = Github Flavored Markdown - set this to render as a document
-			if form.Mode == "gfm" {
-				meta = ctx.Repo.Repository.ComposeDocumentMetas()
-			} else {
-				meta = ctx.Repo.Repository.ComposeMetas()
-			}
-		}
-		if form.Mode == "gfm" {
-			meta["mode"] = "document"
-		}
-
-		if err := markdown.Render(&markup.RenderContext{
-			Ctx:       ctx,
-			URLPrefix: urlPrefix,
-			Metas:     meta,
-			IsWiki:    form.Wiki,
-		}, strings.NewReader(form.Text), ctx.Resp); err != nil {
-			ctx.InternalServerError(err)
-			return
-		}
-	default:
-		if err := markdown.RenderRaw(&markup.RenderContext{
-			Ctx:       ctx,
-			URLPrefix: form.Context,
-		}, strings.NewReader(form.Text), ctx.Resp); err != nil {
-			ctx.InternalServerError(err)
-			return
-		}
-	}
+	common.RenderMarkup(ctx.Context, mode, form.Text, form.Context, "", form.Wiki)
 }
 
 // MarkdownRaw render raw markdown HTML
diff --git a/routers/api/v1/misc/markdown_test.go b/routers/api/v1/misc/markup_test.go
index 025f2f44b0..301f51eea2 100644
--- a/routers/api/v1/misc/markdown_test.go
+++ b/routers/api/v1/misc/markup_test.go
@@ -49,16 +49,37 @@ func wrap(ctx *context.Context) *context.APIContext {
 	}
 }
 
-func TestAPI_RenderGFM(t *testing.T) {
+func testRenderMarkup(t *testing.T, mode, filePath, text, responseBody string, responseCode int) {
+	setting.AppURL = AppURL
+
+	options := api.MarkupOption{
+		Mode:     mode,
+		Text:     "",
+		Context:  Repo,
+		Wiki:     true,
+		FilePath: filePath,
+	}
+	requrl, _ := url.Parse(util.URLJoin(AppURL, "api", "v1", "markup"))
+	req := &http.Request{
+		Method: "POST",
+		URL:    requrl,
+	}
+	m, resp := createContext(req)
+	ctx := wrap(m)
+
+	options.Text = text
+	web.SetForm(ctx, &options)
+	Markup(ctx)
+	assert.Equal(t, responseBody, resp.Body.String())
+	assert.Equal(t, responseCode, resp.Code)
+	resp.Body.Reset()
+}
+
+func testRenderMarkdown(t *testing.T, mode, text, responseBody string, responseCode int) {
 	setting.AppURL = AppURL
-	markup.Init(&markup.ProcessorHelper{
-		IsUsernameMentionable: func(ctx go_context.Context, username string) bool {
-			return username == "r-lyeh"
-		},
-	})
 
 	options := api.MarkdownOption{
-		Mode:    "gfm",
+		Mode:    mode,
 		Text:    "",
 		Context: Repo,
 		Wiki:    true,
@@ -71,7 +92,22 @@ func TestAPI_RenderGFM(t *testing.T) {
 	m, resp := createContext(req)
 	ctx := wrap(m)
 
-	testCases := []string{
+	options.Text = text
+	web.SetForm(ctx, &options)
+	Markdown(ctx)
+	assert.Equal(t, responseBody, resp.Body.String())
+	assert.Equal(t, responseCode, resp.Code)
+	resp.Body.Reset()
+}
+
+func TestAPI_RenderGFM(t *testing.T) {
+	markup.Init(&markup.ProcessorHelper{
+		IsUsernameMentionable: func(ctx go_context.Context, username string) bool {
+			return username == "r-lyeh"
+		},
+	})
+
+	testCasesCommon := []string{
 		// dear imgui wiki markdown extract: special wiki syntax
 		`Wiki! Enjoy :)
 - [[Links, Language bindings, Engine bindings|Links]]
@@ -85,6 +121,23 @@ func TestAPI_RenderGFM(t *testing.T) {
 <li>Bezier widget (by <a href="` + AppURL + `r-lyeh" rel="nofollow">@r-lyeh</a>) <a href="https://github.com/ocornut/imgui/issues/786" rel="nofollow">https://github.com/ocornut/imgui/issues/786</a></li>
 </ul>
 `,
+		// Guard wiki sidebar: special syntax
+		`[[Guardfile-DSL / Configuring-Guard|Guardfile-DSL---Configuring-Guard]]`,
+		// rendered
+		`<p><a href="` + AppSubURL + `wiki/Guardfile-DSL---Configuring-Guard" rel="nofollow">Guardfile-DSL / Configuring-Guard</a></p>
+`,
+		// special syntax
+		`[[Name|Link]]`,
+		// rendered
+		`<p><a href="` + AppSubURL + `wiki/Link" rel="nofollow">Name</a></p>
+`,
+		// empty
+		``,
+		// rendered
+		``,
+	}
+
+	testCasesDocument := []string{
 		// wine-staging wiki home extract: special wiki syntax, images
 		`## What is Wine Staging?
 **Wine Staging** on website [wine-staging.com](http://wine-staging.com).
@@ -103,29 +156,28 @@ Here are some links to the most important topics. You can find the full list of
 <p><a href="` + AppSubURL + `wiki/Configuration" rel="nofollow">Configuration</a>
 <a href="` + AppSubURL + `wiki/raw/images/icon-bug.png" rel="nofollow"><img src="` + AppSubURL + `wiki/raw/images/icon-bug.png" title="icon-bug.png" alt="images/icon-bug.png"/></a></p>
 `,
-		// Guard wiki sidebar: special syntax
-		`[[Guardfile-DSL / Configuring-Guard|Guardfile-DSL---Configuring-Guard]]`,
-		// rendered
-		`<p><a href="` + AppSubURL + `wiki/Guardfile-DSL---Configuring-Guard" rel="nofollow">Guardfile-DSL / Configuring-Guard</a></p>
-`,
-		// special syntax
-		`[[Name|Link]]`,
-		// rendered
-		`<p><a href="` + AppSubURL + `wiki/Link" rel="nofollow">Name</a></p>
-`,
-		// empty
-		``,
-		// rendered
-		``,
 	}
 
-	for i := 0; i < len(testCases); i += 2 {
-		options.Text = testCases[i]
-		web.SetForm(ctx, &options)
-		Markdown(ctx)
-		assert.Equal(t, testCases[i+1], resp.Body.String())
-		resp.Body.Reset()
+	for i := 0; i < len(testCasesCommon); i += 2 {
+		text := testCasesCommon[i]
+		response := testCasesCommon[i+1]
+		testRenderMarkdown(t, "gfm", text, response, http.StatusOK)
+		testRenderMarkup(t, "gfm", "", text, response, http.StatusOK)
+		testRenderMarkdown(t, "comment", text, response, http.StatusOK)
+		testRenderMarkup(t, "comment", "", text, response, http.StatusOK)
+		testRenderMarkup(t, "file", "path/test.md", text, response, http.StatusOK)
 	}
+
+	for i := 0; i < len(testCasesDocument); i += 2 {
+		text := testCasesDocument[i]
+		response := testCasesDocument[i+1]
+		testRenderMarkdown(t, "gfm", text, response, http.StatusOK)
+		testRenderMarkup(t, "gfm", "", text, response, http.StatusOK)
+		testRenderMarkup(t, "file", "path/test.md", text, response, http.StatusOK)
+	}
+
+	testRenderMarkup(t, "file", "path/test.unknown", "## Test", "Unsupported render extension: .unknown\n", http.StatusUnprocessableEntity)
+	testRenderMarkup(t, "unknown", "", "## Test", "Unknown mode: unknown\n", http.StatusUnprocessableEntity)
 }
 
 var simpleCases = []string{
diff --git a/routers/api/v1/swagger/options.go b/routers/api/v1/swagger/options.go
index 0c8d3d353f..1ddc93c383 100644
--- a/routers/api/v1/swagger/options.go
+++ b/routers/api/v1/swagger/options.go
@@ -57,6 +57,8 @@ type swaggerParameterBodies struct {
 	EditLabelOption api.EditLabelOption
 
 	// in:body
+	MarkupOption api.MarkupOption
+	// in:body
 	MarkdownOption api.MarkdownOption
 
 	// in:body
diff --git a/routers/common/markup.go b/routers/common/markup.go
new file mode 100644
index 0000000000..89f24e0007
--- /dev/null
+++ b/routers/common/markup.go
@@ -0,0 +1,92 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package common
+
+import (
+	"fmt"
+	"net/http"
+	"strings"
+
+	"code.gitea.io/gitea/modules/context"
+	"code.gitea.io/gitea/modules/markup"
+	"code.gitea.io/gitea/modules/markup/markdown"
+	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/util"
+
+	"mvdan.cc/xurls/v2"
+)
+
+// RenderMarkup renders markup text for the /markup and /markdown endpoints
+func RenderMarkup(ctx *context.Context, mode, text, urlPrefix, filePath string, wiki bool) {
+	markupType := ""
+	relativePath := ""
+
+	if len(text) == 0 {
+		_, _ = ctx.Write([]byte(""))
+		return
+	}
+
+	switch mode {
+	case "markdown":
+		// Raw markdown
+		if err := markdown.RenderRaw(&markup.RenderContext{
+			Ctx:       ctx,
+			URLPrefix: urlPrefix,
+		}, strings.NewReader(text), ctx.Resp); err != nil {
+			ctx.Error(http.StatusInternalServerError, err.Error())
+		}
+		return
+	case "comment":
+		// Comment as markdown
+		markupType = markdown.MarkupName
+	case "gfm":
+		// Github Flavored Markdown as document
+		markupType = markdown.MarkupName
+	case "file":
+		// File as document based on file extension
+		markupType = ""
+		relativePath = filePath
+	default:
+		ctx.Error(http.StatusUnprocessableEntity, fmt.Sprintf("Unknown mode: %s", mode))
+		return
+	}
+
+	if !strings.HasPrefix(setting.AppSubURL+"/", urlPrefix) {
+		// check if urlPrefix is already set to a URL
+		linkRegex, _ := xurls.StrictMatchingScheme("https?://")
+		m := linkRegex.FindStringIndex(urlPrefix)
+		if m == nil {
+			urlPrefix = util.URLJoin(setting.AppURL, urlPrefix)
+		}
+	}
+
+	meta := map[string]string{}
+	if ctx.Repo != nil && ctx.Repo.Repository != nil {
+		if mode == "comment" {
+			meta = ctx.Repo.Repository.ComposeMetas()
+		} else {
+			meta = ctx.Repo.Repository.ComposeDocumentMetas()
+		}
+	}
+	if mode != "comment" {
+		meta["mode"] = "document"
+	}
+
+	if err := markup.Render(&markup.RenderContext{
+		Ctx:          ctx,
+		URLPrefix:    urlPrefix,
+		Metas:        meta,
+		IsWiki:       wiki,
+		Type:         markupType,
+		RelativePath: relativePath,
+	}, strings.NewReader(text), ctx.Resp); err != nil {
+		if markup.IsErrUnsupportedRenderExtension(err) {
+			ctx.Error(http.StatusUnprocessableEntity, err.Error())
+		} else {
+			ctx.Error(http.StatusInternalServerError, err.Error())
+		}
+		return
+	}
+}
diff --git a/routers/web/misc/markdown.go b/routers/web/misc/markdown.go
deleted file mode 100644
index aaa3ed0781..0000000000
--- a/routers/web/misc/markdown.go
+++ /dev/null
@@ -1,98 +0,0 @@
-// Copyright 2014 The Gogs Authors. All rights reserved.
-// Copyright 2022 The Gitea Authors. All rights reserved.
-// SPDX-License-Identifier: MIT
-
-package misc
-
-import (
-	"net/http"
-	"strings"
-
-	"code.gitea.io/gitea/modules/context"
-	"code.gitea.io/gitea/modules/markup"
-	"code.gitea.io/gitea/modules/markup/markdown"
-	"code.gitea.io/gitea/modules/setting"
-	api "code.gitea.io/gitea/modules/structs"
-	"code.gitea.io/gitea/modules/util"
-	"code.gitea.io/gitea/modules/web"
-
-	"mvdan.cc/xurls/v2"
-)
-
-// Markdown render markdown document to HTML
-func Markdown(ctx *context.Context) {
-	// swagger:operation POST /markdown miscellaneous renderMarkdown
-	// ---
-	// summary: Render a markdown document as HTML
-	// parameters:
-	// - name: body
-	//   in: body
-	//   schema:
-	//     "$ref": "#/definitions/MarkdownOption"
-	// consumes:
-	// - application/json
-	// produces:
-	//     - text/html
-	// responses:
-	//   "200":
-	//     "$ref": "#/responses/MarkdownRender"
-	//   "422":
-	//     "$ref": "#/responses/validationError"
-
-	form := web.GetForm(ctx).(*api.MarkdownOption)
-
-	if ctx.HasAPIError() {
-		ctx.Error(http.StatusUnprocessableEntity, "", ctx.GetErrMsg())
-		return
-	}
-
-	if len(form.Text) == 0 {
-		_, _ = ctx.Write([]byte(""))
-		return
-	}
-
-	switch form.Mode {
-	case "comment":
-		fallthrough
-	case "gfm":
-		urlPrefix := form.Context
-		meta := map[string]string{}
-		if !strings.HasPrefix(setting.AppSubURL+"/", urlPrefix) {
-			// check if urlPrefix is already set to a URL
-			linkRegex, _ := xurls.StrictMatchingScheme("https?://")
-			m := linkRegex.FindStringIndex(urlPrefix)
-			if m == nil {
-				urlPrefix = util.URLJoin(setting.AppURL, form.Context)
-			}
-		}
-		if ctx.Repo != nil && ctx.Repo.Repository != nil {
-			// "gfm" = Github Flavored Markdown - set this to render as a document
-			if form.Mode == "gfm" {
-				meta = ctx.Repo.Repository.ComposeDocumentMetas()
-			} else {
-				meta = ctx.Repo.Repository.ComposeMetas()
-			}
-		}
-		if form.Mode == "gfm" {
-			meta["mode"] = "document"
-		}
-
-		if err := markdown.Render(&markup.RenderContext{
-			Ctx:       ctx,
-			URLPrefix: urlPrefix,
-			Metas:     meta,
-			IsWiki:    form.Wiki,
-		}, strings.NewReader(form.Text), ctx.Resp); err != nil {
-			ctx.Error(http.StatusInternalServerError, err.Error())
-			return
-		}
-	default:
-		if err := markdown.RenderRaw(&markup.RenderContext{
-			Ctx:       ctx,
-			URLPrefix: form.Context,
-		}, strings.NewReader(form.Text), ctx.Resp); err != nil {
-			ctx.Error(http.StatusInternalServerError, err.Error())
-			return
-		}
-	}
-}
diff --git a/routers/web/misc/markup.go b/routers/web/misc/markup.go
new file mode 100644
index 0000000000..f678316f44
--- /dev/null
+++ b/routers/web/misc/markup.go
@@ -0,0 +1,44 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Copyright 2022 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package misc
+
+import (
+	"net/http"
+
+	"code.gitea.io/gitea/modules/context"
+	api "code.gitea.io/gitea/modules/structs"
+	"code.gitea.io/gitea/modules/web"
+	"code.gitea.io/gitea/routers/common"
+)
+
+// Markup render markup document to HTML
+func Markup(ctx *context.Context) {
+	// swagger:operation POST /markup miscellaneous renderMarkup
+	// ---
+	// summary: Render a markup document as HTML
+	// parameters:
+	// - name: body
+	//   in: body
+	//   schema:
+	//     "$ref": "#/definitions/MarkupOption"
+	// consumes:
+	// - application/json
+	// produces:
+	//     - text/html
+	// responses:
+	//   "200":
+	//     "$ref": "#/responses/MarkupRender"
+	//   "422":
+	//     "$ref": "#/responses/validationError"
+
+	form := web.GetForm(ctx).(*api.MarkupOption)
+
+	if ctx.HasAPIError() {
+		ctx.Error(http.StatusUnprocessableEntity, "", ctx.GetErrMsg())
+		return
+	}
+
+	common.RenderMarkup(ctx, form.Mode, form.Text, form.Context, form.FilePath, form.Wiki)
+}
diff --git a/routers/web/repo/editor.go b/routers/web/repo/editor.go
index 07241b8870..2b66be22ae 100644
--- a/routers/web/repo/editor.go
+++ b/routers/web/repo/editor.go
@@ -20,6 +20,7 @@ import (
 	"code.gitea.io/gitea/modules/git"
 	"code.gitea.io/gitea/modules/json"
 	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/markup"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/typesniffer"
 	"code.gitea.io/gitea/modules/upload"
@@ -155,9 +156,8 @@ func editFile(ctx *context.Context, isNewFile bool) {
 	}
 	ctx.Data["new_branch_name"] = GetUniquePatchBranchName(ctx)
 	ctx.Data["last_commit"] = ctx.Repo.CommitID
-	ctx.Data["MarkdownFileExts"] = strings.Join(setting.Markdown.FileExtensions, ",")
+	ctx.Data["PreviewableExtensions"] = strings.Join(markup.PreviewableExtensions(), ",")
 	ctx.Data["LineWrapExtensions"] = strings.Join(setting.Repository.Editor.LineWrapExtensions, ",")
-	ctx.Data["PreviewableFileModes"] = strings.Join(setting.Repository.Editor.PreviewableFileModes, ",")
 	ctx.Data["Editorconfig"] = GetEditorConfig(ctx, treePath)
 
 	ctx.HTML(http.StatusOK, tplEditFile)
@@ -207,9 +207,8 @@ func editFilePost(ctx *context.Context, form forms.EditRepoFileForm, isNewFile b
 	ctx.Data["commit_choice"] = form.CommitChoice
 	ctx.Data["new_branch_name"] = form.NewBranchName
 	ctx.Data["last_commit"] = ctx.Repo.CommitID
-	ctx.Data["MarkdownFileExts"] = strings.Join(setting.Markdown.FileExtensions, ",")
+	ctx.Data["PreviewableExtensions"] = strings.Join(markup.PreviewableExtensions(), ",")
 	ctx.Data["LineWrapExtensions"] = strings.Join(setting.Repository.Editor.LineWrapExtensions, ",")
-	ctx.Data["PreviewableFileModes"] = strings.Join(setting.Repository.Editor.PreviewableFileModes, ",")
 	ctx.Data["Editorconfig"] = GetEditorConfig(ctx, form.TreePath)
 
 	if ctx.HasError() {
diff --git a/routers/web/web.go b/routers/web/web.go
index 292268dc80..4bd2f76c57 100644
--- a/routers/web/web.go
+++ b/routers/web/web.go
@@ -1115,7 +1115,7 @@ func RegisterRoutes(m *web.Route) {
 		m.Group("/comments/{id}", func() {
 			m.Get("/attachments", repo.GetCommentAttachments)
 		})
-		m.Post("/markdown", web.Bind(structs.MarkdownOption{}), misc.Markdown)
+		m.Post("/markup", web.Bind(structs.MarkupOption{}), misc.Markup)
 		m.Group("/labels", func() {
 			m.Post("/new", web.Bind(forms.CreateLabelForm{}), repo.NewLabel)
 			m.Post("/edit", web.Bind(forms.CreateLabelForm{}), repo.UpdateLabel)