Load EasyMDE/CodeMirror dynamically, remove RequireEasyMDE (#18069)

wxiaoguang · web-flow · commit a38ba634a4da · 2022-01-05T13:17:25.000+01:00
This PR makes frontend load EasyMDE/CodeMirror dynamically, and removes `RequireEasyMDE`.
diff --git a/routers/web/repo/commit.go b/routers/web/repo/commit.go
@@ -254,7 +254,6 @@ func FileHistory(ctx *context.Context) {
 func Diff(ctx *context.Context) {
 	ctx.Data["PageIsDiff"] = true
 	ctx.Data["RequireHighlightJS"] = true
-	ctx.Data["RequireEasyMDE"] = true
 	ctx.Data["RequireTribute"] = true
 
 	userName := ctx.Repo.Owner.Name
diff --git a/routers/web/repo/compare.go b/routers/web/repo/compare.go
@@ -764,7 +764,6 @@ func CompareDiff(ctx *context.Context) {
 	ctx.Data["IsRepoToolbarCommits"] = true
 	ctx.Data["IsDiffCompare"] = true
 	ctx.Data["RequireTribute"] = true
-	ctx.Data["RequireEasyMDE"] = true
 	setTemplateIfExists(ctx, pullRequestTemplateKey, nil, pullRequestTemplateCandidates)
 	ctx.Data["IsAttachmentEnabled"] = setting.Attachment.Enabled
 	upload.AddUploadContext(ctx, "comment")
diff --git a/routers/web/repo/editor.go b/routers/web/repo/editor.go
@@ -69,7 +69,6 @@ func editFile(ctx *context.Context, isNewFile bool) {
 	ctx.Data["PageIsEdit"] = true
 	ctx.Data["IsNewFile"] = isNewFile
 	ctx.Data["RequireHighlightJS"] = true
-	ctx.Data["RequireEasyMDE"] = true
 	canCommit := renderCommitRights(ctx)
 
 	treePath := cleanUploadFileName(ctx.Repo.TreePath)
@@ -200,7 +199,6 @@ func editFilePost(ctx *context.Context, form forms.EditRepoFileForm, isNewFile b
 	ctx.Data["PageHasPosted"] = true
 	ctx.Data["IsNewFile"] = isNewFile
 	ctx.Data["RequireHighlightJS"] = true
-	ctx.Data["RequireEasyMDE"] = true
 	ctx.Data["TreePath"] = form.TreePath
 	ctx.Data["TreeNames"] = treeNames
 	ctx.Data["TreePaths"] = treePaths
@@ -544,7 +542,6 @@ func DeleteFilePost(ctx *context.Context) {
 func UploadFile(ctx *context.Context) {
 	ctx.Data["PageIsUpload"] = true
 	ctx.Data["RequireTribute"] = true
-	ctx.Data["RequireEasyMDE"] = true
 	upload.AddUploadContext(ctx, "repo")
 	canCommit := renderCommitRights(ctx)
 	treePath := cleanUploadFileName(ctx.Repo.TreePath)
@@ -580,7 +577,6 @@ func UploadFilePost(ctx *context.Context) {
 	form := web.GetForm(ctx).(*forms.UploadRepoFileForm)
 	ctx.Data["PageIsUpload"] = true
 	ctx.Data["RequireTribute"] = true
-	ctx.Data["RequireEasyMDE"] = true
 	upload.AddUploadContext(ctx, "repo")
 	canCommit := renderCommitRights(ctx)
 
diff --git a/routers/web/repo/issue.go b/routers/web/repo/issue.go
@@ -789,7 +789,6 @@ func NewIssue(ctx *context.Context) {
 	ctx.Data["PageIsIssueList"] = true
 	ctx.Data["NewIssueChooseTemplate"] = len(ctx.IssueTemplatesFromDefaultBranch()) > 0
 	ctx.Data["RequireHighlightJS"] = true
-	ctx.Data["RequireEasyMDE"] = true
 	ctx.Data["RequireTribute"] = true
 	ctx.Data["PullRequestWorkInProgressPrefixes"] = setting.Repository.PullRequest.WorkInProgressPrefixes
 	title := ctx.FormString("title")
@@ -962,7 +961,6 @@ func NewIssuePost(ctx *context.Context) {
 	ctx.Data["PageIsIssueList"] = true
 	ctx.Data["NewIssueChooseTemplate"] = len(ctx.IssueTemplatesFromDefaultBranch()) > 0
 	ctx.Data["RequireHighlightJS"] = true
-	ctx.Data["RequireEasyMDE"] = true
 	ctx.Data["PullRequestWorkInProgressPrefixes"] = setting.Repository.PullRequest.WorkInProgressPrefixes
 	ctx.Data["IsAttachmentEnabled"] = setting.Attachment.Enabled
 	upload.AddUploadContext(ctx, "comment")
@@ -1147,7 +1145,6 @@ func ViewIssue(ctx *context.Context) {
 
 	ctx.Data["RequireHighlightJS"] = true
 	ctx.Data["RequireTribute"] = true
-	ctx.Data["RequireEasyMDE"] = true
 	ctx.Data["IsProjectsEnabled"] = ctx.Repo.CanRead(unit.TypeProjects)
 	ctx.Data["IsAttachmentEnabled"] = setting.Attachment.Enabled
 	upload.AddUploadContext(ctx, "comment")
diff --git a/routers/web/repo/pull.go b/routers/web/repo/pull.go
@@ -738,7 +738,6 @@ func ViewPullFiles(ctx *context.Context) {
 	setCompareContext(ctx, baseCommit, commit, ctx.Repo.Owner.Name, ctx.Repo.Repository.Name)
 
 	ctx.Data["RequireHighlightJS"] = true
-	ctx.Data["RequireEasyMDE"] = true
 	ctx.Data["RequireTribute"] = true
 	if ctx.Data["Assignees"], err = models.GetRepoAssignees(ctx.Repo.Repository); err != nil {
 		ctx.ServerError("GetAssignees", err)
@@ -1098,7 +1097,6 @@ func CompareAndPullRequestPost(ctx *context.Context) {
 	ctx.Data["IsDiffCompare"] = true
 	ctx.Data["IsRepoToolbarCommits"] = true
 	ctx.Data["RequireTribute"] = true
-	ctx.Data["RequireEasyMDE"] = true
 	ctx.Data["RequireHighlightJS"] = true
 	ctx.Data["PullRequestWorkInProgressPrefixes"] = setting.Repository.PullRequest.WorkInProgressPrefixes
 	ctx.Data["IsAttachmentEnabled"] = setting.Attachment.Enabled
diff --git a/routers/web/repo/release.go b/routers/web/repo/release.go
@@ -262,7 +262,6 @@ func LatestRelease(ctx *context.Context) {
 func NewRelease(ctx *context.Context) {
 	ctx.Data["Title"] = ctx.Tr("repo.release.new_release")
 	ctx.Data["PageIsReleaseList"] = true
-	ctx.Data["RequireEasyMDE"] = true
 	ctx.Data["RequireTribute"] = true
 	ctx.Data["tag_target"] = ctx.Repo.Repository.DefaultBranch
 	if tagName := ctx.FormString("tag"); len(tagName) > 0 {
@@ -296,7 +295,6 @@ func NewReleasePost(ctx *context.Context) {
 	form := web.GetForm(ctx).(*forms.NewReleaseForm)
 	ctx.Data["Title"] = ctx.Tr("repo.release.new_release")
 	ctx.Data["PageIsReleaseList"] = true
-	ctx.Data["RequireEasyMDE"] = true
 	ctx.Data["RequireTribute"] = true
 
 	if ctx.HasError() {
@@ -415,7 +413,6 @@ func EditRelease(ctx *context.Context) {
 	ctx.Data["Title"] = ctx.Tr("repo.release.edit_release")
 	ctx.Data["PageIsReleaseList"] = true
 	ctx.Data["PageIsEditRelease"] = true
-	ctx.Data["RequireEasyMDE"] = true
 	ctx.Data["RequireTribute"] = true
 	ctx.Data["IsAttachmentEnabled"] = setting.Attachment.Enabled
 	upload.AddUploadContext(ctx, "release")
@@ -454,7 +451,6 @@ func EditReleasePost(ctx *context.Context) {
 	ctx.Data["Title"] = ctx.Tr("repo.release.edit_release")
 	ctx.Data["PageIsReleaseList"] = true
 	ctx.Data["PageIsEditRelease"] = true
-	ctx.Data["RequireEasyMDE"] = true
 	ctx.Data["RequireTribute"] = true
 
 	tagName := ctx.Params("*")
diff --git a/routers/web/repo/wiki.go b/routers/web/repo/wiki.go
@@ -622,7 +622,6 @@ func WikiRaw(ctx *context.Context) {
 func NewWiki(ctx *context.Context) {
 	ctx.Data["Title"] = ctx.Tr("repo.wiki.new_page")
 	ctx.Data["PageIsWiki"] = true
-	ctx.Data["RequireEasyMDE"] = true
 
 	if !ctx.Repo.Repository.HasWiki() {
 		ctx.Data["title"] = "Home"
@@ -639,7 +638,6 @@ func NewWikiPost(ctx *context.Context) {
 	form := web.GetForm(ctx).(*forms.NewWikiForm)
 	ctx.Data["Title"] = ctx.Tr("repo.wiki.new_page")
 	ctx.Data["PageIsWiki"] = true
-	ctx.Data["RequireEasyMDE"] = true
 
 	if ctx.HasError() {
 		ctx.HTML(http.StatusOK, tplWikiNew)
@@ -677,7 +675,6 @@ func NewWikiPost(ctx *context.Context) {
 func EditWiki(ctx *context.Context) {
 	ctx.Data["PageIsWiki"] = true
 	ctx.Data["PageIsWikiEdit"] = true
-	ctx.Data["RequireEasyMDE"] = true
 
 	if !ctx.Repo.Repository.HasWiki() {
 		ctx.Redirect(ctx.Repo.RepoLink + "/wiki")
@@ -697,7 +694,6 @@ func EditWikiPost(ctx *context.Context) {
 	form := web.GetForm(ctx).(*forms.NewWikiForm)
 	ctx.Data["Title"] = ctx.Tr("repo.wiki.new_page")
 	ctx.Data["PageIsWiki"] = true
-	ctx.Data["RequireEasyMDE"] = true
 
 	if ctx.HasError() {
 		ctx.HTML(http.StatusOK, tplWikiNew)
diff --git a/templates/base/footer.tmpl b/templates/base/footer.tmpl
@@ -12,14 +12,6 @@
 	{{template "custom/body_outer_post" .}}
 
 	{{template "base/footer_content" .}}
-{{if .RequireEasyMDE}}
-	<script src="{{AssetUrlPrefix}}/js/easymde.js?v={{MD5 AppVer}}"></script>
-	<script src="{{AssetUrlPrefix}}/vendor/plugins/codemirror/addon/mode/loadmode.js"></script>
-	<script src="{{AssetUrlPrefix}}/vendor/plugins/codemirror/mode/meta.js"></script>
-	<script>
-		CodeMirror.modeURL = '{{AssetUrlPrefix}}/vendor/plugins/codemirror/mode/%N/%N.js';
-	</script>
-{{end}}
 
 <!-- Third-party libraries -->
 {{if .RequireU2F}}
diff --git a/templates/base/head.tmpl b/templates/base/head.tmpl
@@ -59,9 +59,6 @@
 	</script>
 	<link rel="icon" href="{{AssetUrlPrefix}}/img/logo.svg" type="image/svg+xml">
 	<link rel="alternate icon" href="{{AssetUrlPrefix}}/img/favicon.png" type="image/png">
-{{if .RequireEasyMDE}}
-	<link rel="stylesheet" href="{{AssetUrlPrefix}}/css/easymde.css?v={{MD5 AppVer}}">
-{{end}}
 	<link rel="stylesheet" href="{{AssetUrlPrefix}}/css/index.css?v={{MD5 AppVer}}">
 	<noscript>
 		<style>
diff --git a/web_src/js/easymde.js b/web_src/js/easymde.js
diff --git a/web_src/js/features/comp/EasyMDE.js b/web_src/js/features/comp/EasyMDE.js
@@ -1,24 +1,72 @@
 import attachTribute from '../tribute.js';
 
+const {appSubUrl} = window.config;
+
+function loadScript(url) {
+  return new Promise((resolve, reject) => {
+    const script = document.createElement('script');
+    script.async = true;
+    script.addEventListener('load', () => {
+      resolve();
+    });
+    script.addEventListener('error', (e) => {
+      reject(e.error);
+    });
+    script.src = url;
+    document.body.appendChild(script);
+  });
+}
+
+/**
+ * @returns {EasyMDE}
+ */
+export async function importEasyMDE() {
+  // for CodeMirror: the plugins should be loaded dynamically
+  // https://github.com/codemirror/CodeMirror/issues/5484
+  // https://github.com/codemirror/CodeMirror/issues/4838
+
+  const [{default: EasyMDE}, {default: CodeMirror}] = await Promise.all([
+    import(/* webpackChunkName: "easymde" */'easymde'),
+    import(/* webpackChunkName: "codemirror" */'codemirror'),
+    import(/* webpackChunkName: "easymde" */'easymde/dist/easymde.min.css'),
+  ]);
+
+  // CodeMirror plugins must be loaded by a "Plain browser env"
+  window.CodeMirror = CodeMirror;
+  await Promise.all([
+    loadScript(`${appSubUrl}/assets/vendor/plugins/codemirror/addon/mode/loadmode.js`),
+    loadScript(`${appSubUrl}/assets/vendor/plugins/codemirror/mode/meta.js`),
+  ]);
+
+  // the loadmode.js/meta.js would set the modeURL/modeInfo properties, so we check it to make sure our loading works
+  if (!CodeMirror.modeURL || !CodeMirror.modeInfo) {
+    throw new Error('failed to load plugins for CodeMirror');
+  }
+
+  CodeMirror.modeURL = `${appSubUrl}/assets/vendor/plugins/codemirror/mode/%N/%N.js`;
+  return EasyMDE;
+}
+
 /**
  * create an EasyMDE editor for comment
  * @param textarea jQuery or HTMLElement
  * @returns {null|EasyMDE}
  */
-export function createCommentEasyMDE(textarea) {
+export async function createCommentEasyMDE(textarea) {
   if (textarea instanceof jQuery) {
     textarea = textarea[0];
   }
   if (!textarea) {
     return null;
   }
 
-  const easyMDE = new window.EasyMDE({
+  const EasyMDE = await importEasyMDE();
+  const easyMDE = new EasyMDE({
     autoDownloadFontAwesome: false,
     element: textarea,
     forceSync: true,
     renderingConfig: {
-      singleLineBreaks: false
+      singleLineBreaks: false,
     },
     indentWithTabs: false,
     tabSize: 4,
@@ -56,23 +104,23 @@ export function createCommentEasyMDE(textarea) {
         className: 'fa fa-file',
         title: 'Revert to simple textarea',
       },
-    ]
+    ],
   });
   const inputField = easyMDE.codemirror.getInputField();
   inputField.classList.add('js-quick-submit');
   easyMDE.codemirror.setOption('extraKeys', {
     Enter: () => {
       const tributeContainer = document.querySelector('.tribute-container');
       if (!tributeContainer || tributeContainer.style.display === 'none') {
-        return CodeMirror.Pass;
+        return window.CodeMirror.Pass;
       }
     },
     Backspace: (cm) => {
       if (cm.getInputField().trigger) {
         cm.getInputField().trigger('input');
       }
       cm.execCommand('delCharBefore');
-    }
+    },
   });
   attachTribute(inputField, {mentions: true, emoji: true});
   attachEasyMDEToElements(easyMDE);
diff --git a/web_src/js/features/repo-diff.js b/web_src/js/features/repo-diff.js
@@ -1,6 +1,6 @@
 import {initCompReactionSelector} from './comp/ReactionSelector.js';
 import {initRepoIssueContentHistory} from './repo-issue-content.js';
-import {validateTextareaNonEmpty} from './comp/CommentEasyMDE.js';
+import {validateTextareaNonEmpty} from './comp/EasyMDE.js';
 const {csrfToken} = window.config;
 
 export function initRepoDiffReviewButton() {
diff --git a/web_src/js/features/repo-issue.js b/web_src/js/features/repo-issue.js
@@ -1,6 +1,6 @@
 import {htmlEscape} from 'escape-goat';
 import attachTribute from './tribute.js';
-import {createCommentEasyMDE, getAttachedEasyMDE} from './comp/CommentEasyMDE.js';
+import {createCommentEasyMDE, getAttachedEasyMDE} from './comp/EasyMDE.js';
 import {initCompImagePaste} from './comp/ImagePaste.js';
 import {initCompMarkupContentPreviewTab} from './comp/MarkupContentPreview.js';
 
@@ -439,16 +439,17 @@ export function initRepoPullRequestReview() {
     $(`#show-outdated-${id}`).removeClass('hide');
   });
 
-  $(document).on('click', 'button.comment-form-reply', function (e) {
+  $(document).on('click', 'button.comment-form-reply', async function (e) {
     e.preventDefault();
+
     $(this).hide();
     const form = $(this).closest('.comment-code-cloud').find('.comment-form');
     form.removeClass('hide');
     const $textarea = form.find('textarea');
     let easyMDE = getAttachedEasyMDE($textarea);
     if (!easyMDE) {
-      attachTribute($textarea.get(), {mentions: true, emoji: true});
-      easyMDE = createCommentEasyMDE($textarea);
+      await attachTribute($textarea.get(), {mentions: true, emoji: true});
+      easyMDE = await createCommentEasyMDE($textarea);
     }
     $textarea.focus();
     easyMDE.codemirror.focus();
@@ -515,8 +516,8 @@ export function initRepoPullRequestReview() {
       td.find("input[name='side']").val(side === 'left' ? 'previous' : 'proposed');
       td.find("input[name='path']").val(path);
       const $textarea = commentCloud.find('textarea');
-      attachTribute($textarea.get(), {mentions: true, emoji: true});
-      const easyMDE = createCommentEasyMDE($textarea);
+      await attachTribute($textarea.get(), {mentions: true, emoji: true});
+      const easyMDE = await createCommentEasyMDE($textarea);
       $textarea.focus();
       easyMDE.codemirror.focus();
     }
diff --git a/web_src/js/features/repo-legacy.js b/web_src/js/features/repo-legacy.js
@@ -1,4 +1,4 @@
-import {createCommentEasyMDE, getAttachedEasyMDE} from './comp/CommentEasyMDE.js';
+import {createCommentEasyMDE, getAttachedEasyMDE} from './comp/EasyMDE.js';
 import {initCompMarkupContentPreviewTab} from './comp/MarkupContentPreview.js';
 import {initCompImagePaste, initEasyMDEImagePaste} from './comp/ImagePaste.js';
 import {
@@ -256,6 +256,7 @@ export function initRepoCommentForm() {
 
 async function onEditContent(event) {
   event.preventDefault();
+
   $(this).closest('.dropdown').find('.menu').toggle('visible');
   const $segment = $(this).closest('.header').next();
   const $editContentZone = $segment.find('.edit-content-zone');
@@ -341,7 +342,7 @@ async function onEditContent(event) {
     $tabMenu.find('.preview.item').attr('data-tab', $editContentZone.data('preview'));
     $editContentForm.find('.write').attr('data-tab', $editContentZone.data('write'));
     $editContentForm.find('.preview').attr('data-tab', $editContentZone.data('preview'));
-    easyMDE = createCommentEasyMDE($textarea);
+    easyMDE = await createCommentEasyMDE($textarea);
 
     initCompMarkupContentPreviewTab($editContentForm);
     if ($dropzone.length === 1) {
diff --git a/web_src/js/features/repo-release.js b/web_src/js/features/repo-release.js
@@ -1,7 +1,7 @@
 import attachTribute from './tribute.js';
 import {initCompMarkupContentPreviewTab} from './comp/MarkupContentPreview.js';
 import {initEasyMDEImagePaste} from './comp/ImagePaste.js';
-import {createCommentEasyMDE} from './comp/CommentEasyMDE.js';
+import {createCommentEasyMDE} from './comp/EasyMDE.js';
 
 export function initRepoRelease() {
   $(document).on('click', '.remove-rel-attach', function() {
@@ -19,11 +19,13 @@ export function initRepoReleaseEditor() {
     return false;
   }
 
-  const $textarea = $editor.find('textarea');
-  attachTribute($textarea.get(), {mentions: false, emoji: true});
-  const $files = $editor.parent().find('.files');
-  const easyMDE = createCommentEasyMDE($textarea);
-  initCompMarkupContentPreviewTab($editor);
-  const dropzone = $editor.parent().find('.dropzone')[0];
-  initEasyMDEImagePaste(easyMDE, dropzone, $files);
+  (async () => {
+    const $textarea = $editor.find('textarea');
+    await attachTribute($textarea.get(), {mentions: false, emoji: true});
+    const $files = $editor.parent().find('.files');
+    const easyMDE = await createCommentEasyMDE($textarea);
+    initCompMarkupContentPreviewTab($editor);
+    const dropzone = $editor.parent().find('.dropzone')[0];
+    initEasyMDEImagePaste(easyMDE, dropzone, $files);
+  })();
 }
diff --git a/web_src/js/features/repo-wiki.js b/web_src/js/features/repo-wiki.js
diff --git a/webpack.config.js b/webpack.config.js
