chore: save downloads to outputDir (#310)

src/config.ts

@@ -20,10 +20,9 @@ import os from 'os';
 import path from 'path';
 import { devices } from 'playwright';
 
-import { sanitizeForFilePath } from './tools/utils.js';
-
 import type { Config, ToolCapability } from '../config.js';
 import type { BrowserContextOptions, LaunchOptions } from 'playwright';
+import { sanitizeForFilePath } from './tools/utils.js';
 
 export type CLIOptions = {
   browser?: string;

src/context.ts

@@ -23,6 +23,7 @@ import { Tab } from './tab.js';
 import type { ImageContent, TextContent } from '@modelcontextprotocol/sdk/types.js';
 import type { ModalState, Tool, ToolActionResult } from './tools/tool.js';
 import type { Config } from '../config.js';
+import { outputFile } from './config.js';
 
 type PendingAction = {
   dialogShown: ManualPromise<void>;
@@ -38,6 +39,7 @@ export class Context {
   private _currentTab: Tab | undefined;
   private _modalStates: (ModalState & { tab: Tab })[] = [];
   private _pendingAction: PendingAction | undefined;
+  private _downloads: { download: playwright.Download, finished: boolean, outputFile: string }[] = [];
 
   constructor(tools: Tool[], config: Config) {
     this.tools = tools;
@@ -164,6 +166,17 @@ ${code.join('\n')}
       };
     }
 
+    if (this._downloads.length) {
+      result.push('', '### Downloads');
+      for (const entry of this._downloads) {
+        if (entry.finished)
+          result.push(`- Downloaded file ${entry.download.suggestedFilename()} to ${entry.outputFile}`);
+        else
+          result.push(`- Downloading file ${entry.download.suggestedFilename()} ...`);
+      }
+      result.push('');
+    }
+
     if (this.tabs().length > 1)
       result.push(await this.listTabsMarkdown(), '');
 
@@ -228,6 +241,17 @@ ${code.join('\n')}
     this._pendingAction?.dialogShown.resolve();
   }
 
+  async downloadStarted(tab: Tab, download: playwright.Download) {
+    const entry = {
+      download,
+      finished: false,
+      outputFile: await outputFile(this.config, download.suggestedFilename())
+    };
+    this._downloads.push(entry);
+    await download.saveAs(entry.outputFile);
+    entry.finished = true;
+  }
+
   private _onPageCreated(page: playwright.Page) {
     const tab = new Tab(this, page, tab => this._onPageClosed(tab));
     this._tabs.push(tab);

src/tab.ts

@@ -48,6 +48,9 @@ export class Tab {
       }, this);
     });
     page.on('dialog', dialog => this.context.dialogShown(this, dialog));
+    page.on('download', download => {
+      void this.context.downloadStarted(this, download);
+    });
     page.setDefaultNavigationTimeout(60000);
     page.setDefaultTimeout(5000);
   }

src/tools/pdf.ts

@@ -31,7 +31,7 @@ const pdf = defineTool({
 
   handle: async context => {
     const tab = context.currentTabOrDie();
-    const fileName = await outputFile(context.config, `page-${new Date().toISOString()}'.pdf'`);
+    const fileName = await outputFile(context.config, `page-${new Date().toISOString()}.pdf`);
 
     const code = [
       `// Save page as ${fileName}`,

tests/files.spec.ts

@@ -16,6 +16,7 @@
 
 import { test, expect } from './fixtures.js';
 import fs from 'fs/promises';
+import path from 'path';
 
 test('browser_file_upload', async ({ client }) => {
   expect(await client.callTool({
@@ -96,3 +97,27 @@ The tool "browser_file_upload" can only be used when there is related modal stat
 - [File chooser]: can be handled by the "browser_file_upload" tool`);
   }
 });
+
+test('clicking on download link emits download', async ({ startClient }, testInfo) => {
+  const outputDir = testInfo.outputPath('output');
+  const client = await startClient({
+    config: { outputDir },
+  });
+
+  expect(await client.callTool({
+    name: 'browser_navigate',
+    arguments: {
+      url: 'data:text/html,<a href="data:text/plain,Hello world!" download="test.txt">Download</a>',
+    },
+  })).toContainTextContent('- link "Download" [ref=s1e3]');
+
+  await expect.poll(() => client.callTool({
+    name: 'browser_click',
+    arguments: {
+      element: 'Download link',
+      ref: 's1e3',
+    },
+  })).toContainTextContent(`
+### Downloads
+- Downloaded file test.txt to ${path.join(outputDir, 'test-txt')}`);
+});