/*--------------------------------------------------------------------------------------------- * Copyright (c) Microsoft Corporation. All rights reserved. * Licensed under the MIT License. See License.txt in the project root for license information. *--------------------------------------------------------------------------------------------*/ import * as DOM from './dom.js'; import * as dompurify from './dompurify/dompurify.js'; import { DomEmitter } from './event.js'; import { createElement } from './formattedTextRenderer.js'; import { StandardMouseEvent } from './mouseEvent.js'; import { renderLabelWithIcons } from './ui/iconLabel/iconLabels.js'; import { raceCancellation } from '../common/async.js'; import { CancellationTokenSource } from '../common/cancellation.js'; import { onUnexpectedError } from '../common/errors.js'; import { Event } from '../common/event.js'; import { parseHrefAndDimensions, removeMarkdownEscapes } from '../common/htmlContent.js'; import { markdownEscapeEscapedIcons } from '../common/iconLabels.js'; import { defaultGenerator } from '../common/idGenerator.js'; import { DisposableStore } from '../common/lifecycle.js'; import * as marked from '../common/marked/marked.js'; import { parse } from '../common/marshalling.js'; import { FileAccess, Schemas } from '../common/network.js'; import { cloneAndChange } from '../common/objects.js'; import { resolvePath } from '../common/resources.js'; import { escape } from '../common/strings.js'; import { URI } from '../common/uri.js'; /** * Low-level way create a html element from a markdown string. * * **Note** that for most cases you should be using [`MarkdownRenderer`](./src/vs/editor/browser/core/markdownRenderer.ts) * which comes with support for pretty code block rendering and which uses the default way of handling links. */ export function renderMarkdown(markdown, options = {}, markedOptions = {}) { var _a; const disposables = new DisposableStore(); let isDisposed = false; const cts = disposables.add(new CancellationTokenSource()); const element = createElement(options); const _uriMassage = function (part) { let data; try { data = parse(decodeURIComponent(part)); } catch (e) { // ignore } if (!data) { return part; } data = cloneAndChange(data, value => { if (markdown.uris && markdown.uris[value]) { return URI.revive(markdown.uris[value]); } else { return undefined; } }); return encodeURIComponent(JSON.stringify(data)); }; const _href = function (href, isDomUri) { const data = markdown.uris && markdown.uris[href]; let uri = URI.revive(data); if (isDomUri) { if (href.startsWith(Schemas.data + ':')) { return href; } if (!uri) { uri = URI.parse(href); } // this URI will end up as "src"-attribute of a dom node // and because of that special rewriting needs to be done // so that the URI uses a protocol that's understood by // browsers (like http or https) return FileAccess.asBrowserUri(uri).toString(true); } if (!uri) { return href; } if (URI.parse(href).toString() === uri.toString()) { return href; // no transformation performed } if (uri.query) { uri = uri.with({ query: _uriMassage(uri.query) }); } return uri.toString(); }; // signal to code-block render that the // element has been created let signalInnerHTML; const withInnerHTML = new Promise(c => signalInnerHTML = c); const renderer = new marked.Renderer(); renderer.image = (href, title, text) => { let dimensions = []; let attributes = []; if (href) { ({ href, dimensions } = parseHrefAndDimensions(href)); attributes.push(`src="${href}"`); } if (text) { attributes.push(`alt="${text}"`); } if (title) { attributes.push(`title="${title}"`); } if (dimensions.length) { attributes = attributes.concat(dimensions); } return ''; }; renderer.link = (href, title, text) => { // Remove markdown escapes. Workaround for https://github.com/chjj/marked/issues/829 if (href === text) { // raw link case text = removeMarkdownEscapes(text); } href = _href(href, false); if (options.baseUrl) { const hasScheme = /^\w[\w\d+.-]*:/.test(href); if (!hasScheme) { href = resolvePath(options.baseUrl, href).toString(); } } title = removeMarkdownEscapes(title); href = removeMarkdownEscapes(href); if (!href || href.match(/^data:|javascript:/i) || (href.match(/^command:/i) && !markdown.isTrusted) || href.match(/^command:(\/\/\/)?_workbench\.downloadResource/i)) { // drop the link return text; } else { // HTML Encode href href = href.replace(/&/g, '&') .replace(//g, '>') .replace(/"/g, '"') .replace(/'/g, '''); return `${text}`; } }; renderer.paragraph = (text) => { return `

${text}

`; }; if (options.codeBlockRenderer) { renderer.code = (code, lang) => { const value = options.codeBlockRenderer(lang, code); // when code-block rendering is async we return sync // but update the node with the real result later. const id = defaultGenerator.nextId(); raceCancellation(Promise.all([value, withInnerHTML]), cts.token).then(values => { var _a; if (!isDisposed && values) { const span = element.querySelector(`div[data-code="${id}"]`); if (span) { DOM.reset(span, values[0]); } (_a = options.asyncRenderCallback) === null || _a === void 0 ? void 0 : _a.call(options); } }).catch(() => { // ignore }); return `
${escape(code)}
`; }; } if (options.actionHandler) { const onClick = options.actionHandler.disposables.add(new DomEmitter(element, 'click')); const onAuxClick = options.actionHandler.disposables.add(new DomEmitter(element, 'auxclick')); options.actionHandler.disposables.add(Event.any(onClick.event, onAuxClick.event)(e => { const mouseEvent = new StandardMouseEvent(e); if (!mouseEvent.leftButton && !mouseEvent.middleButton) { return; } let target = mouseEvent.target; if (target.tagName !== 'A') { target = target.parentElement; if (!target || target.tagName !== 'A') { return; } } try { const href = target.dataset['href']; if (href) { options.actionHandler.callback(href, mouseEvent); } } catch (err) { onUnexpectedError(err); } finally { mouseEvent.preventDefault(); } })); } if (!markdown.supportHtml) { // TODO: Can we deprecated this in favor of 'supportHtml'? // Use our own sanitizer so that we can let through only spans. // Otherwise, we'd be letting all html be rendered. // If we want to allow markdown permitted tags, then we can delete sanitizer and sanitize. // We always pass the output through dompurify after this so that we don't rely on // marked for sanitization. markedOptions.sanitizer = (html) => { const match = markdown.isTrusted ? html.match(/^(]+>)|(<\/\s*span>)$/) : undefined; return match ? html : ''; }; markedOptions.sanitize = true; markedOptions.silent = true; } markedOptions.renderer = renderer; // values that are too long will freeze the UI let value = (_a = markdown.value) !== null && _a !== void 0 ? _a : ''; if (value.length > 100000) { value = `${value.substr(0, 100000)}…`; } // escape theme icons if (markdown.supportThemeIcons) { value = markdownEscapeEscapedIcons(value); } let renderedMarkdown = marked.parse(value, markedOptions); // Rewrite theme icons if (markdown.supportThemeIcons) { const elements = renderLabelWithIcons(renderedMarkdown); renderedMarkdown = elements.map(e => typeof e === 'string' ? e : e.outerHTML).join(''); } const htmlParser = new DOMParser(); const markdownHtmlDoc = htmlParser.parseFromString(sanitizeRenderedMarkdown(markdown, renderedMarkdown), 'text/html'); markdownHtmlDoc.body.querySelectorAll('img') .forEach(img => { if (img.src) { let href = _href(img.src, true); try { const hrefAsUri = URI.parse(href); if (options.baseUrl && hrefAsUri.scheme === Schemas.file) { // absolute or relative local path, or file: uri href = resolvePath(options.baseUrl, href).toString(); } } catch (err) { } img.src = href; } }); element.innerHTML = sanitizeRenderedMarkdown(markdown, markdownHtmlDoc.body.innerHTML); // signal that async code blocks can be now be inserted signalInnerHTML(); // signal size changes for image tags if (options.asyncRenderCallback) { for (const img of element.getElementsByTagName('img')) { const listener = disposables.add(DOM.addDisposableListener(img, 'load', () => { listener.dispose(); options.asyncRenderCallback(); })); } } return { element, dispose: () => { isDisposed = true; cts.cancel(); disposables.dispose(); } }; } function sanitizeRenderedMarkdown(options, renderedMarkdown) { const { config, allowedSchemes } = getSanitizerOptions(options); dompurify.addHook('uponSanitizeAttribute', (element, e) => { if (e.attrName === 'style' || e.attrName === 'class') { if (element.tagName === 'SPAN') { if (e.attrName === 'style') { e.keepAttr = /^(color\:#[0-9a-fA-F]+;)?(background-color\:#[0-9a-fA-F]+;)?$/.test(e.attrValue); return; } else if (e.attrName === 'class') { e.keepAttr = /^codicon codicon-[a-z\-]+( codicon-modifier-[a-z\-]+)?$/.test(e.attrValue); return; } } e.keepAttr = false; return; } }); // build an anchor to map URLs to const anchor = document.createElement('a'); // https://github.com/cure53/DOMPurify/blob/main/demos/hooks-scheme-allowlist.html dompurify.addHook('afterSanitizeAttributes', (node) => { // check all href/src attributes for validity for (const attr of ['href', 'src']) { if (node.hasAttribute(attr)) { anchor.href = node.getAttribute(attr); if (!allowedSchemes.includes(anchor.protocol.replace(/:$/, ''))) { node.removeAttribute(attr); } } } }); try { return dompurify.sanitize(renderedMarkdown, Object.assign(Object.assign({}, config), { RETURN_TRUSTED_TYPE: true })); } finally { dompurify.removeHook('uponSanitizeAttribute'); dompurify.removeHook('afterSanitizeAttributes'); } } function getSanitizerOptions(options) { const allowedSchemes = [ Schemas.http, Schemas.https, Schemas.mailto, Schemas.data, Schemas.file, Schemas.vscodeFileResource, Schemas.vscodeRemote, Schemas.vscodeRemoteResource, ]; if (options.isTrusted) { allowedSchemes.push(Schemas.command); } return { config: { // allowedTags should included everything that markdown renders to. // Since we have our own sanitize function for marked, it's possible we missed some tag so let dompurify make sure. // HTML tags that can result from markdown are from reading https://spec.commonmark.org/0.29/ // HTML table tags that can result from markdown are from https://github.github.com/gfm/#tables-extension- ALLOWED_TAGS: ['ul', 'li', 'p', 'b', 'i', 'code', 'blockquote', 'ol', 'h1', 'h2', 'h3', 'h4', 'h5', 'h6', 'hr', 'em', 'pre', 'table', 'thead', 'tbody', 'tr', 'th', 'td', 'div', 'del', 'a', 'strong', 'br', 'img', 'span'], ALLOWED_ATTR: ['href', 'data-href', 'target', 'title', 'src', 'alt', 'class', 'style', 'data-code', 'width', 'height', 'align'], ALLOW_UNKNOWN_PROTOCOLS: true, }, allowedSchemes }; }