@browserless/capture: Record a Puppeteer page using tabCapture API.

Install

npm install @browserless/capture --save

Usage

const createBrowser = require('browserless')
const createCapture = require('@browserless/capture')

const withCaptureExtension = (launchOpts = {}) => {
  const ignoreDefaultArgs = launchOpts.ignoreDefaultArgs

  return {
    ...launchOpts,
    args: [
      ...(launchOpts.args || []),
      `--allowlisted-extension-id=${createCapture.extensionId}`,
      `--disable-extensions-except=${createCapture.extensionPath}`,
      `--load-extension=${createCapture.extensionPath}`
    ],
    ignoreDefaultArgs:
      ignoreDefaultArgs === true
        ? true
        : [
            ...new Set([
              ...(Array.isArray(ignoreDefaultArgs) ? ignoreDefaultArgs : []),
              '--disable-extensions'
            ])
          ]
  }
}

const browser = createBrowser(withCaptureExtension({ headless: 'new' }))

const browserless = await browser.createContext()
const puppeteerBrowser = await browserless.browser()
const page = await puppeteerBrowser.defaultBrowserContext().newPage()
const capture = createCapture({ goto: browserless.goto })

const video = await capture(page)('https://example.com', {
  duration: 5000,
  type: 'mp4',
  codec: 'avc1.4D401F',
  path: '/tmp/demo.mp4'
})

await page.close()
await browserless.destroyContext()
await browser.close()

browserless core does not inject capture extension flags automatically. @browserless/capture requires:

• Loading the bundled extension using --allowlisted-extension-id, --disable-extensions-except, and --load-extension.
• Ensuring Chromium default arg --disable-extensions is ignored.
• Creating the captured page from defaultBrowserContext() (not an incognito context).

API shape is intentionally simple, similar to page.screenshot()/page.pdf():

const capture = createCapture({ goto })
await capture(page)(url, opts)

Returns a Buffer and writes to opts.path when provided.

Options

Option	Type	Default	Description
type	'webm' | 'mp4'	'mp4'	Output type selector mapped to MediaRecorder mime type.
codec	string	Depends on type	MediaRecorder codec override. Defaults: webm -> vp9, mp4 -> avc1.4D401F.
path	string	undefined	Write the captured media to disk.
duration	number	3000	Capture duration in milliseconds.
audio	boolean | object	false	Capture audio. When object, it is used as audio track constraints.
video	boolean | object	true	Capture video. When object, it is used as video track constraints.

Exports

• capture.extensionPath: Absolute path to the bundled extension.
• capture.extensionId: Extension ID used by the package.
• capture.types: Supported values for type. capture uses goto(...).device.viewport as the capture viewport source. When video is true or omitted, video constraints are inferred from that viewport to keep capture framing aligned with screenshot/pdf rendering. When video is an object, that object is used as the video constraints. When audio is an object, that object is used as the audio constraints. The inferred constraints also account for deviceScaleFactor, so output video pixels match screenshot pixel density. type is mapped internally to the MediaRecorder mime type, and codec is appended as ;codecs=.... Default codecs are vp9 for webm and avc1.4D401F for mp4. You can override codec per request using opts.codec. For example:

await capture(page)(url, { type: 'webm', codec: 'vp8' })
await capture(page)(url, { type: 'mp4', codec: 'avc1.640033' })

When type is 'mp4', the running Chromium build must support MP4 MediaRecorder output. For strict screenshot/poster parity in headless mode, launch Chrome with matching --screen-info.

License

@browserless/capture © Microlink, released under the MIT License.