chore: allow specifying output dir (#285)

Ref: https://github.com/microsoft/playwright-mcp/issues/279

src/config.ts

@@ -14,8 +14,12 @@
  * limitations under the License.
  */
 
+import fs from 'fs';
 import net from 'net';
 import os from 'os';
+import path from 'path';
+
+import { sanitizeForFilePath } from './tools/utils';
 
 import type { Config } from '../config';
 import type { LaunchOptions, BrowserContextOptions } from 'playwright';
@@ -84,3 +88,10 @@ async function findFreePort() {
     server.on('error', reject);
   });
 }
+
+export async function outputFile(config: Config, name: string): Promise<string> {
+  const result = config.outputDir ?? os.tmpdir();
+  await fs.promises.mkdir(result, { recursive: true });
+  const fileName = sanitizeForFilePath(name);
+  return path.join(result, fileName);
+}

src/tools/pdf.ts

@@ -14,14 +14,11 @@
  * limitations under the License.
  */
 
-import os from 'os';
-import path from 'path';
-
 import { z } from 'zod';
 import { defineTool } from './tool';
 
-import { sanitizeForFilePath } from './utils';
 import * as javascript from '../javascript';
+import { outputFile } from '../config';
 
 const pdf = defineTool({
   capability: 'pdf',
@@ -34,7 +31,7 @@ const pdf = defineTool({
 
   handle: async context => {
     const tab = context.currentTabOrDie();
-    const fileName = path.join(os.tmpdir(), sanitizeForFilePath(`page-${new Date().toISOString()}`)) + '.pdf';
+    const fileName = await outputFile(context.config, `page-${new Date().toISOString()}'.pdf'`);
 
     const code = [
       `// Save page as ${fileName}`,

src/tools/snapshot.ts

@@ -14,14 +14,11 @@
  * limitations under the License.
  */
 
-import path from 'path';
-import os from 'os';
-
 import { z } from 'zod';
 
-import { sanitizeForFilePath } from './utils';
 import { defineTool } from './tool';
 import * as javascript from '../javascript';
+import { outputFile } from '../config';
 
 import type * as playwright from 'playwright';
 
@@ -232,7 +229,7 @@ const screenshot = defineTool({
     const tab = context.currentTabOrDie();
     const snapshot = tab.snapshotOrDie();
     const fileType = params.raw ? 'png' : 'jpeg';
-    const fileName = path.join(os.tmpdir(), sanitizeForFilePath(`page-${new Date().toISOString()}`)) + `.${fileType}`;
+    const fileName = await outputFile(context.config, `page-${new Date().toISOString()}.${fileType}`);
     const options: playwright.PageScreenshotOptions = { type: fileType, quality: fileType === 'png' ? undefined : 50, scale: 'css', path: fileName };
     const isElementScreenshot = params.element && params.ref;