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>

custom/conf/app.example.ini

@@ -993,10 +993,6 @@ ROUTER = console
 ;; List of file extensions for which lines should be wrapped in the Monaco editor
 ;; Separate extensions with a comma. To line wrap files without an extension, just put a comma
 ;LINE_WRAP_EXTENSIONS = .txt,.md,.markdown,.mdown,.mkd,
-;;
-;; Valid file modes that have a preview API associated with them, such as api/v1/markdown
-;; Separate the values by commas. The preview tab in edit mode won't be displayed if the file extension doesn't match
-;PREVIEWABLE_FILE_MODES = markdown
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

modules/markup/renderer.go

@@ -283,6 +283,11 @@ type ErrUnsupportedRenderExtension struct {
 	Extension string
 }
 
+func IsErrUnsupportedRenderExtension(err error) bool {
+	_, ok := err.(ErrUnsupportedRenderExtension)
+	return ok
+}
+
 func (err ErrUnsupportedRenderExtension) Error() string {
 	return fmt.Sprintf("Unsupported render extension: %s", err.Extension)
 }
@@ -317,3 +322,11 @@ func IsMarkupFile(name, markup string) bool {
 	}
 	return false
 }
+
+func PreviewableExtensions() []string {
+	extensions := make([]string, 0, len(extRenderers))
+	for extension := range extRenderers {
+		extensions = append(extensions, extension)
+	}
+	return extensions
+}

modules/setting/repository.go

@@ -54,7 +54,6 @@ var (
 		// Repository editor settings
 		Editor struct {
 			LineWrapExtensions []string
-			PreviewableFileModes []string
 		} `ini:"-"`
 
 		// Repository upload settings
@@ -168,10 +167,8 @@ var (
 		// Repository editor settings
 		Editor: struct {
 			LineWrapExtensions []string
-			PreviewableFileModes []string
 		}{
 			LineWrapExtensions: strings.Split(".txt,.md,.markdown,.mdown,.mkd,", ","),
-			PreviewableFileModes: []string{"markdown"},
 		},
 
 		// Repository upload settings

modules/structs/miscellaneous.go

@@ -15,13 +15,41 @@ type SearchError struct {
 	Error string `json:"error"`
 }
 
+// MarkupOption markup options
+type MarkupOption struct {
+	// Text markup to render
+	//
+	// in: body
+	Text string
+	// Mode to render (comment, gfm, markdown, file)
+	//
+	// in: body
+	Mode string
+	// Context to render
+	//
+	// in: body
+	Context string
+	// Is it a wiki page ?
+	//
+	// in: body
+	Wiki bool
+	// File path for detecting extension in file mode
+	//
+	// in: body
+	FilePath string
+}
+
+// MarkupRender is a rendered markup document
+// swagger:response MarkupRender
+type MarkupRender string
+
 // MarkdownOption markdown options
 type MarkdownOption struct {
 	// Text markdown to render
 	//
 	// in: body
 	Text string
-	// Mode to render
+	// Mode to render (comment, gfm, markdown)
 	//
 	// in: body
 	Mode string

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() {

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

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{

routers/api/v1/swagger/options.go

@@ -56,6 +56,8 @@ type swaggerParameterBodies struct {
 	// in:body
 	EditLabelOption api.EditLabelOption
 
+	// in:body
+	MarkupOption api.MarkupOption
 	// in:body
 	MarkdownOption api.MarkdownOption
 

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
+	}
+}

routers/web/misc/markdown.go

@@ -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
-		}
-	}
-}

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)
+}

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() {

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)

templates/repo/diff/box.tmpl

@@ -192,7 +192,7 @@
 				<div class="ui comment form">
 					<div class="ui top attached tabular menu">
 						<a class="active write item">{{$.locale.Tr "write"}}</a>
-						<a class="preview item" data-url="{{$.Repository.Link}}/markdown" data-context="{{$.RepoLink}}">{{$.locale.Tr "preview"}}</a>
+						<a class="preview item" data-url="{{$.Repository.Link}}/markup" data-context="{{$.RepoLink}}">{{$.locale.Tr "preview"}}</a>
 					</div>
 					<div class="ui bottom attached active write tab segment">
 						<textarea class="review-textarea js-quick-submit" tabindex="1" name="content"></textarea>

templates/repo/diff/comment_form.tmpl

@@ -11,7 +11,7 @@
 		<input type="hidden" name="diff_base_cid">
 		<div class="ui top tabular menu" data-write="write" data-preview="preview">
 			<a class="active item" data-tab="write">{{$.root.locale.Tr "write"}}</a>
-			<a class="item" data-tab="preview" data-url="{{$.root.Repository.Link}}/markdown" data-context="{{$.root.RepoLink}}">{{$.root.locale.Tr "preview"}}</a>
+			<a class="item" data-tab="preview" data-url="{{$.root.Repository.Link}}/markup" data-context="{{$.root.RepoLink}}">{{$.root.locale.Tr "preview"}}</a>
 		</div>
 		<div class="field">
 			<div class="ui active tab" data-tab="write">

templates/repo/editor/edit.tmpl

@@ -31,15 +31,15 @@
 				<div class="ui top attached tabular menu" data-write="write" data-preview="preview" data-diff="diff">
 					<a class="active item" data-tab="write">{{svg "octicon-code"}} {{if .IsNewFile}}{{.locale.Tr "repo.editor.new_file"}}{{else}}{{.locale.Tr "repo.editor.edit_file"}}{{end}}</a>
 					{{if not .IsNewFile}}
-					<a class="item" data-tab="preview" data-url="{{.Repository.Link}}/markdown" data-context="{{.RepoLink}}/src/{{.BranchNameSubURL}}" data-preview-file-modes="{{.PreviewableFileModes}}" data-markdown-mode="gfm">{{svg "octicon-eye"}} {{.locale.Tr "preview"}}</a>
+					<a class="item" data-tab="preview" data-url="{{.Repository.Link}}/markup" data-context="{{.RepoLink}}/src/{{.BranchNameSubURL}}" data-markup-mode="file">{{svg "octicon-eye"}} {{.locale.Tr "preview"}}</a>
 					<a class="item" data-tab="diff" data-url="{{.RepoLink}}/_preview/{{.BranchName | PathEscapeSegments}}/{{.TreePath | PathEscapeSegments}}" data-context="{{.BranchLink}}">{{svg "octicon-diff"}} {{.locale.Tr "repo.editor.preview_changes"}}</a>
 					{{end}}
 				</div>
 				<div class="ui bottom attached active tab segment" data-tab="write">
 					<textarea id="edit_area" name="content" class="gt-hidden" data-id="repo-{{.Repository.Name}}-{{.TreePath}}"
-						data-url="{{.Repository.Link}}/markdown"
+						data-url="{{.Repository.Link}}/markup"
 						data-context="{{.RepoLink}}"
-						data-markdown-file-exts="{{.MarkdownFileExts}}"
+						data-previewable-extensions="{{.PreviewableExtensions}}"
 						data-line-wrap-extensions="{{.LineWrapExtensions}}">
 {{.FileContent}}</textarea>
 					<div class="editor-loading is-loading"></div>

templates/repo/issue/comment_tab.tmpl

@@ -1,10 +1,10 @@
 	<div class="ui top tabular menu" data-write="write" data-preview="preview">
 		<a class="active item" data-tab="write">{{.locale.Tr "write"}}</a>
-		<a class="item" data-tab="preview" data-url="{{.Repository.Link}}/markdown" data-context="{{.RepoLink}}">{{.locale.Tr "preview"}}</a>
+		<a class="item" data-tab="preview" data-url="{{.Repository.Link}}/markup" data-context="{{.RepoLink}}">{{.locale.Tr "preview"}}</a>
 	</div>
 	<div class="field">
 		<div class="ui bottom active tab" data-tab="write">
-		<textarea id="content" class="edit_area js-quick-submit" name="content" tabindex="4" data-id="issue-{{.RepoName}}" data-url="{{.Repository.Link}}/markdown" data-context="{{.Repo.RepoLink}}">
+		<textarea id="content" class="edit_area js-quick-submit" name="content" tabindex="4" data-id="issue-{{.RepoName}}" data-url="{{.Repository.Link}}/markup" data-context="{{.Repo.RepoLink}}">
 			{{- if .BodyQuery}}{{.BodyQuery}}{{else if .IssueTemplate}}{{.IssueTemplate}}{{else if .PullRequestTemplate}}{{.PullRequestTemplate}}{{else}}{{.content}}{{end -}}
 		</textarea>
 		</div>

templates/repo/issue/view_content.tmpl

@@ -168,7 +168,7 @@
 	<div class="ui comment form">
 		<div class="ui top tabular menu">
 			<a class="active write item">{{$.locale.Tr "write"}}</a>
-			<a class="preview item" data-url="{{$.Repository.Link}}/markdown" data-context="{{$.RepoLink}}">{{$.locale.Tr "preview"}}</a>
+			<a class="preview item" data-url="{{$.Repository.Link}}/markup" data-context="{{$.RepoLink}}">{{$.locale.Tr "preview"}}</a>
 		</div>
 		<div class="field">
 			<div class="ui bottom active tab write">

templates/repo/release/new.tmpl

@@ -53,7 +53,7 @@
 					<label>{{.locale.Tr "repo.release.content"}}</label>
 					<div class="ui top tabular menu" data-write="write" data-preview="preview">
 						<a class="active write item" data-tab="write">{{$.locale.Tr "write"}}</a>
-						<a class="preview item" data-tab="preview" data-url="{{$.Repository.Link}}/markdown" data-context="{{$.RepoLink}}">{{$.locale.Tr "preview"}}</a>
+						<a class="preview item" data-tab="preview" data-url="{{$.Repository.Link}}/markup" data-context="{{$.RepoLink}}">{{$.locale.Tr "preview"}}</a>
 					</div>
 					<div class="ui bottom active tab" data-tab="write">
 						<textarea name="content">{{.content}}</textarea>

templates/repo/wiki/new.tmpl

@@ -21,11 +21,11 @@
 			</div>
 			<div class="ui top attached tabular menu previewtabs" data-write="write" data-preview="preview">
 				<a class="active item" data-tab="write">{{.locale.Tr "write"}}</a>
-				<a class="item" data-tab="preview" data-url="{{$.Repository.Link}}/markdown" data-context="{{$.RepoLink}}">{{$.locale.Tr "preview"}}</a>
+				<a class="item" data-tab="preview" data-url="{{$.Repository.Link}}/markup" data-context="{{$.RepoLink}}">{{$.locale.Tr "preview"}}</a>
 			</div>
 			<div class="field content" data-loading="{{.locale.Tr "loading"}}">
 				<div class="ui bottom active tab" data-tab="write">
-					<textarea class="js-quick-submit" id="edit_area" name="content" data-id="wiki-{{.title}}" data-url="{{.Repository.Link}}/markdown" data-context="{{.RepoLink}}">{{if .PageIsWikiEdit}}{{.content}}{{else}}{{.locale.Tr "repo.wiki.welcome"}}{{end}}</textarea>
+					<textarea class="js-quick-submit" id="edit_area" name="content" data-id="wiki-{{.title}}" data-url="{{.Repository.Link}}/markup" data-context="{{.RepoLink}}">{{if .PageIsWikiEdit}}{{.content}}{{else}}{{.locale.Tr "repo.wiki.welcome"}}{{end}}</textarea>
 				</div>
 			</div>
 			<div class="field">

templates/swagger/v1_json.tmpl

@@ -951,6 +951,38 @@
         }
       }
     },
+    "/markup": {
+      "post": {
+        "consumes": [
+          "application/json"
+        ],
+        "produces": [
+          "text/html"
+        ],
+        "tags": [
+          "miscellaneous"
+        ],
+        "summary": "Render a markup document as HTML",
+        "operationId": "renderMarkup",
+        "parameters": [
+          {
+            "name": "body",
+            "in": "body",
+            "schema": {
+              "$ref": "#/definitions/MarkupOption"
+            }
+          }
+        ],
+        "responses": {
+          "200": {
+            "$ref": "#/responses/MarkupRender"
+          },
+          "422": {
+            "$ref": "#/responses/validationError"
+          }
+        }
+      }
+    },
     "/nodeinfo": {
       "get": {
         "produces": [
@@ -17991,7 +18023,7 @@
           "type": "string"
         },
         "Mode": {
-          "description": "Mode to render\n\nin: body",
+          "description": "Mode to render (comment, gfm, markdown)\n\nin: body",
           "type": "string"
         },
         "Text": {
@@ -18005,6 +18037,33 @@
       },
       "x-go-package": "code.gitea.io/gitea/modules/structs"
     },
+    "MarkupOption": {
+      "description": "MarkupOption markup options",
+      "type": "object",
+      "properties": {
+        "Context": {
+          "description": "Context to render\n\nin: body",
+          "type": "string"
+        },
+        "FilePath": {
+          "description": "File path for detecting extension in file mode\n\nin: body",
+          "type": "string"
+        },
+        "Mode": {
+          "description": "Mode to render (comment, gfm, markdown, file)\n\nin: body",
+          "type": "string"
+        },
+        "Text": {
+          "description": "Text markup to render\n\nin: body",
+          "type": "string"
+        },
+        "Wiki": {
+          "description": "Is it a wiki page ?\n\nin: body",
+          "type": "boolean"
+        }
+      },
+      "x-go-package": "code.gitea.io/gitea/modules/structs"
+    },
     "MergePullRequestOption": {
       "description": "MergePullRequestForm form for merging Pull Request",
       "type": "object",
@@ -20835,6 +20894,12 @@
         "type": "string"
       }
     },
+    "MarkupRender": {
+      "description": "MarkupRender is a rendered markup document",
+      "schema": {
+        "type": "string"
+      }
+    },
     "Milestone": {
       "description": "Milestone",
       "schema": {

web_src/js/features/codeeditor.js

@@ -130,17 +130,17 @@ function getFileBasedOptions(filename, lineWrapExts) {
   };
 }
 
-export async function createCodeEditor(textarea, filenameInput, previewFileModes) {
+export async function createCodeEditor(textarea, filenameInput) {
   const filename = basename(filenameInput.value);
   const previewLink = document.querySelector('a[data-tab=preview]');
-  const markdownExts = (textarea.getAttribute('data-markdown-file-exts') || '').split(',');
+  const previewableExts = (textarea.getAttribute('data-previewable-extensions') || '').split(',');
   const lineWrapExts = (textarea.getAttribute('data-line-wrap-extensions') || '').split(',');
-  const isMarkdown = markdownExts.includes(extname(filename));
+  const previewable = previewableExts.includes(extname(filename));
   const editorConfig = getEditorconfig(filenameInput);
 
   if (previewLink) {
-    if (isMarkdown && (previewFileModes || []).includes('markdown')) {
-      const newUrl = (previewLink.getAttribute('data-url') || '').replace(/(.*)\/.*/i, `$1/markdown`);
+    if (previewable) {
+      const newUrl = (previewLink.getAttribute('data-url') || '').replace(/(.*)\/.*/i, `$1/markup`);
       previewLink.setAttribute('data-url', newUrl);
       previewLink.style.display = '';
     } else {

web_src/js/features/repo-editor.js

@@ -5,18 +5,16 @@ import {createCodeEditor} from './codeeditor.js';
 import {hideElem, showElem} from '../utils/dom.js';
 
 const {csrfToken} = window.config;
-let previewFileModes;
 
 function initEditPreviewTab($form) {
   const $tabMenu = $form.find('.tabular.menu');
   $tabMenu.find('.item').tab();
   const $previewTab = $tabMenu.find(`.item[data-tab="${$tabMenu.data('preview')}"]`);
   if ($previewTab.length) {
-    previewFileModes = $previewTab.data('preview-file-modes').split(',');
     $previewTab.on('click', function () {
       const $this = $(this);
       let context = `${$this.data('context')}/`;
-      const mode = $this.data('markdown-mode') || 'comment';
+      const mode = $this.data('markup-mode') || 'comment';
       const treePathEl = $form.find('input#tree_path');
       if (treePathEl.length > 0) {
         context += treePathEl.val();
@@ -27,6 +25,7 @@ function initEditPreviewTab($form) {
         mode,
         context,
         text: $form.find(`.tab[data-tab="${$tabMenu.data('write')}"] textarea`).val(),
+        file_path: treePathEl.val(),
       }, (data) => {
         const $previewPanel = $form.find(`.tab[data-tab="${$tabMenu.data('preview')}"]`);
         $previewPanel.html(data);
@@ -147,7 +146,7 @@ export function initRepoEditor() {
   if (!$editArea.length) return;
 
   (async () => {
-    const editor = await createCodeEditor($editArea[0], $editFilename[0], previewFileModes);
+    const editor = await createCodeEditor($editArea[0], $editFilename[0]);
 
     // Using events from https://github.com/codedance/jquery.AreYouSure#advanced-usage
     // to enable or disable the commit button