CoCalc -- documentRenderer.ts

GitHub Repository: microsoft/vscode
Path: blob/main/extensions/markdown-language-features/src/preview/documentRenderer.ts
³²⁹² views
1
/*---------------------------------------------------------------------------------------------
2
 *  Copyright (c) Microsoft Corporation. All rights reserved.
3
 *  Licensed under the MIT License. See License.txt in the project root for license information.
4
 *--------------------------------------------------------------------------------------------*/
5

6
import * as vscode from 'vscode';
7
import * as uri from 'vscode-uri';
8
import { ILogger } from '../logging';
9
import { MarkdownItEngine } from '../markdownEngine';
10
import { MarkdownContributionProvider } from '../markdownExtensions';
11
import { escapeAttribute, getNonce } from '../util/dom';
12
import { WebviewResourceProvider } from '../util/resources';
13
import { MarkdownPreviewConfiguration, MarkdownPreviewConfigurationManager } from './previewConfig';
14
import { ContentSecurityPolicyArbiter, MarkdownPreviewSecurityLevel } from './security';
15

16

17
/**
18
 * Strings used inside the markdown preview.
19
 *
20
 * Stored here and then injected in the preview so that they
21
 * can be localized using our normal localization process.
22
 */
23
const previewStrings = {
24
	cspAlertMessageText: vscode.l10n.t("Some content has been disabled in this document"),
25

26
	cspAlertMessageTitle: vscode.l10n.t("Potentially unsafe or insecure content has been disabled in the Markdown preview. Change the Markdown preview security setting to allow insecure content or enable scripts"),
27

28
	cspAlertMessageLabel: vscode.l10n.t("Content Disabled Security Warning")
29
};
30

31
export interface MarkdownContentProviderOutput {
32
	html: string;
33
	containingImages: Set<string>;
34
}
35

36
export interface ImageInfo {
37
	readonly id: string;
38
	readonly width: number;
39
	readonly height: number;
40
}
41

42
export class MdDocumentRenderer {
43
	constructor(
44
		private readonly _engine: MarkdownItEngine,
45
		private readonly _context: vscode.ExtensionContext,
46
		private readonly _cspArbiter: ContentSecurityPolicyArbiter,
47
		private readonly _contributionProvider: MarkdownContributionProvider,
48
		private readonly _logger: ILogger
49
	) {
50
		this.iconPath = {
51
			dark: vscode.Uri.joinPath(this._context.extensionUri, 'media', 'preview-dark.svg'),
52
			light: vscode.Uri.joinPath(this._context.extensionUri, 'media', 'preview-light.svg'),
53
		};
54
	}
55

56
	public readonly iconPath: { light: vscode.Uri; dark: vscode.Uri };
57

58
	public async renderDocument(
59
		markdownDocument: vscode.TextDocument,
60
		resourceProvider: WebviewResourceProvider,
61
		previewConfigurations: MarkdownPreviewConfigurationManager,
62
		initialLine: number | undefined,
63
		selectedLine: number | undefined,
64
		state: any | undefined,
65
		imageInfo: readonly ImageInfo[],
66
		token: vscode.CancellationToken
67
	): Promise<MarkdownContentProviderOutput> {
68
		const sourceUri = markdownDocument.uri;
69
		const config = previewConfigurations.loadAndCacheConfiguration(sourceUri);
70
		const initialData = {
71
			source: sourceUri.toString(),
72
			fragment: state?.fragment || markdownDocument.uri.fragment || undefined,
73
			line: initialLine,
74
			selectedLine,
75
			scrollPreviewWithEditor: config.scrollPreviewWithEditor,
76
			scrollEditorWithPreview: config.scrollEditorWithPreview,
77
			doubleClickToSwitchToEditor: config.doubleClickToSwitchToEditor,
78
			disableSecurityWarnings: this._cspArbiter.shouldDisableSecurityWarnings(),
79
			webviewResourceRoot: resourceProvider.asWebviewUri(markdownDocument.uri).toString(),
80
		};
81

82
		this._logger.trace('DocumentRenderer', `provideTextDocumentContent - ${markdownDocument.uri}`, initialData);
83

84
		// Content Security Policy
85
		const nonce = getNonce();
86
		const csp = this._getCsp(resourceProvider, sourceUri, nonce);
87

88
		const body = await this.renderBody(markdownDocument, resourceProvider);
89
		if (token.isCancellationRequested) {
90
			return { html: '', containingImages: new Set() };
91
		}
92

93
		const html = `<!DOCTYPE html>
94
			<html style="${escapeAttribute(this._getSettingsOverrideStyles(config))}">
95
			<head>
96
				<meta http-equiv="Content-type" content="text/html;charset=UTF-8">
97
				<meta http-equiv="Content-Security-Policy" content="${escapeAttribute(csp)}">
98
				<meta id="vscode-markdown-preview-data"
99
					data-settings="${escapeAttribute(JSON.stringify(initialData))}"
100
					data-strings="${escapeAttribute(JSON.stringify(previewStrings))}"
101
					data-state="${escapeAttribute(JSON.stringify(state || {}))}"
102
					data-initial-md-content="${escapeAttribute(body.html)}">
103
				<script src="${this._extensionResourcePath(resourceProvider, 'pre.js')}" nonce="${nonce}"></script>
104
				${this._getStyles(resourceProvider, sourceUri, config, imageInfo)}
105
				<base href="${resourceProvider.asWebviewUri(markdownDocument.uri)}">
106
			</head>
107
			<body class="vscode-body ${config.scrollBeyondLastLine ? 'scrollBeyondLastLine' : ''} ${config.wordWrap ? 'wordWrap' : ''} ${config.markEditorSelection ? 'showEditorSelection' : ''}">
108
				${this._getScripts(resourceProvider, nonce)}
109
			</body>
110
			</html>`;
111
		return {
112
			html,
113
			containingImages: body.containingImages,
114
		};
115
	}
116

117
	public async renderBody(
118
		markdownDocument: vscode.TextDocument,
119
		resourceProvider: WebviewResourceProvider,
120
	): Promise<MarkdownContentProviderOutput> {
121
		const rendered = await this._engine.render(markdownDocument, resourceProvider);
122
		const html = `<div class="markdown-body" dir="auto">${rendered.html}<div class="code-line" data-line="${markdownDocument.lineCount}"></div></div>`;
123
		return {
124
			html,
125
			containingImages: rendered.containingImages
126
		};
127
	}
128

129
	public renderFileNotFoundDocument(resource: vscode.Uri): string {
130
		const resourcePath = uri.Utils.basename(resource);
131
		const body = vscode.l10n.t('{0} cannot be found', resourcePath);
132
		return `<!DOCTYPE html>
133
			<html>
134
			<body class="vscode-body">
135
				${body}
136
			</body>
137
			</html>`;
138
	}
139

140
	private _extensionResourcePath(resourceProvider: WebviewResourceProvider, mediaFile: string): string {
141
		const webviewResource = resourceProvider.asWebviewUri(
142
			vscode.Uri.joinPath(this._context.extensionUri, 'media', mediaFile));
143
		return webviewResource.toString();
144
	}
145

146
	private _fixHref(resourceProvider: WebviewResourceProvider, resource: vscode.Uri, href: string): string {
147
		if (!href) {
148
			return href;
149
		}
150

151
		if (href.startsWith('http:') || href.startsWith('https:') || href.startsWith('file:')) {
152
			return href;
153
		}
154

155
		// Assume it must be a local file
156
		if (href.startsWith('/') || /^[a-z]:\\/i.test(href)) {
157
			return resourceProvider.asWebviewUri(vscode.Uri.file(href)).toString();
158
		}
159

160
		// Use a workspace relative path if there is a workspace
161
		const root = vscode.workspace.getWorkspaceFolder(resource);
162
		if (root) {
163
			return resourceProvider.asWebviewUri(vscode.Uri.joinPath(root.uri, href)).toString();
164
		}
165

166
		// Otherwise look relative to the markdown file
167
		return resourceProvider.asWebviewUri(vscode.Uri.joinPath(uri.Utils.dirname(resource), href)).toString();
168
	}
169

170
	private _computeCustomStyleSheetIncludes(resourceProvider: WebviewResourceProvider, resource: vscode.Uri, config: MarkdownPreviewConfiguration): string {
171
		if (!Array.isArray(config.styles)) {
172
			return '';
173
		}
174
		const out: string[] = [];
175
		for (const style of config.styles) {
176
			out.push(`<link rel="stylesheet" class="code-user-style" data-source="${escapeAttribute(style)}" href="${escapeAttribute(this._fixHref(resourceProvider, resource, style))}" type="text/css" media="screen">`);
177
		}
178
		return out.join('\n');
179
	}
180

181
	private _getSettingsOverrideStyles(config: MarkdownPreviewConfiguration): string {
182
		return [
183
			config.fontFamily ? `--markdown-font-family: ${config.fontFamily};` : '',
184
			isNaN(config.fontSize) ? '' : `--markdown-font-size: ${config.fontSize}px;`,
185
			isNaN(config.lineHeight) ? '' : `--markdown-line-height: ${config.lineHeight};`,
186
		].join(' ');
187
	}
188

189
	private _getImageStabilizerStyles(imageInfo: readonly ImageInfo[]): string {
190
		if (!imageInfo.length) {
191
			return '';
192
		}
193

194
		let ret = '<style>\n';
195
		for (const imgInfo of imageInfo) {
196
			ret += `#${imgInfo.id}.loading {
197
					height: ${imgInfo.height}px;
198
					width: ${imgInfo.width}px;
199
				}\n`;
200
		}
201
		ret += '</style>\n';
202

203
		return ret;
204
	}
205

206
	private _getStyles(resourceProvider: WebviewResourceProvider, resource: vscode.Uri, config: MarkdownPreviewConfiguration, imageInfo: readonly ImageInfo[]): string {
207
		const baseStyles: string[] = [];
208
		for (const resource of this._contributionProvider.contributions.previewStyles) {
209
			baseStyles.push(`<link rel="stylesheet" type="text/css" href="${escapeAttribute(resourceProvider.asWebviewUri(resource))}">`);
210
		}
211

212
		return `${baseStyles.join('\n')}
213
			${this._computeCustomStyleSheetIncludes(resourceProvider, resource, config)}
214
			${this._getImageStabilizerStyles(imageInfo)}`;
215
	}
216

217
	private _getScripts(resourceProvider: WebviewResourceProvider, nonce: string): string {
218
		const out: string[] = [];
219
		for (const resource of this._contributionProvider.contributions.previewScripts) {
220
			out.push(`<script async
221
				src="${escapeAttribute(resourceProvider.asWebviewUri(resource))}"
222
				nonce="${nonce}"
223
				charset="UTF-8"></script>`);
224
		}
225
		return out.join('\n');
226
	}
227

228
	private _getCsp(
229
		provider: WebviewResourceProvider,
230
		resource: vscode.Uri,
231
		nonce: string
232
	): string {
233
		const rule = provider.cspSource.split(';')[0];
234
		switch (this._cspArbiter.getSecurityLevelForResource(resource)) {
235
			case MarkdownPreviewSecurityLevel.AllowInsecureContent:
236
				return `default-src 'none'; img-src 'self' ${rule} http: https: data:; media-src 'self' ${rule} http: https: data:; script-src 'nonce-${nonce}'; style-src 'self' ${rule} 'unsafe-inline' http: https: data:; font-src 'self' ${rule} http: https: data:;`;
237

238
			case MarkdownPreviewSecurityLevel.AllowInsecureLocalContent:
239
				return `default-src 'none'; img-src 'self' ${rule} https: data: http://localhost:* http://127.0.0.1:*; media-src 'self' ${rule} https: data: http://localhost:* http://127.0.0.1:*; script-src 'nonce-${nonce}'; style-src 'self' ${rule} 'unsafe-inline' https: data: http://localhost:* http://127.0.0.1:*; font-src 'self' ${rule} https: data: http://localhost:* http://127.0.0.1:*;`;
240

241
			case MarkdownPreviewSecurityLevel.AllowScriptsAndAllContent:
242
				return ``;
243

244
			case MarkdownPreviewSecurityLevel.Strict:
245
			default:
246
				return `default-src 'none'; img-src 'self' ${rule} https: data:; media-src 'self' ${rule} https: data:; script-src 'nonce-${nonce}'; style-src 'self' ${rule} 'unsafe-inline' https: data:; font-src 'self' ${rule} https: data:;`;
247
		}
248
	}
249
}
250

251
Product

Resources

Company
