| """ Handle the prerendering navigation request and insert the received client |
| info to the returned page. |
| """ |
| |
| import textwrap |
| |
| html_template = """ |
| <!DOCTYPE html> |
| <html> |
| <head> |
| <title>echo client hints on prerendering page</title> |
| </head> |
| <script src="/speculation-rules/prerender/resources/utils.js"></script> |
| <body> |
| <script> |
| |
| // Allow generator to add the received CH information into this script. |
| %s |
| |
| const params = new URLSearchParams(location.search); |
| const uid = params.get('uid'); |
| |
| // Performs the following checks on prerendering pages: |
| // 1. The client did not send server_received_full_version_list when fetching |
| // the prerendering main resource. |
| // 2. The request initiated by the prerendering page is sent with |
| // sec-ch-ua-full-version-list attached, because the server asked the |
| // prerendering page to attach this hint for the following requests. |
| // If any of the checks fails, it will ask the main test page to terminate |
| // the test. |
| // Otherwise, it asks the initiator page to perform activation, and informs |
| // the main test page of the test success upon being activated. This is used |
| // to verify that the initiator page's client hints cache is not modified by |
| // the prerendering page, i.e., the initiator page does not attach |
| // sec-ch-ua-full-version-list to the requests. |
| async function load_as_prerendering_page() { |
| // The first prerendering request should not contain the field of |
| // sec-ch-ua-full-version-list, as prerender is initiated by the initial |
| // page. |
| if (!server_received_bitness || server_received_full_version_list) { |
| failTest( |
| `Prerender page saw unexpected request headers. |
| bitness: ${server_received_bitness}, |
| full_version: ${server_received_full_version_list}`, |
| uid); |
| } |
| const r = |
| await fetch('../resources/echo-subresource-client-hints-received.py'); |
| if (r.status != 200 || r.headers.get('server_received_bitness') !== 'true' || |
| r.headers.get('server_received_full_version_list') !== 'true') { |
| failTest( |
| `Prerender page saw unexpected headers while fetching |
| sub-resources. |
| bitness: ${r.headers.get('server_received_bitness')}, |
| full_version: ${ |
| r.headers.get('server_received_full_version_list')}`, |
| uid); |
| } else { |
| document.onprerenderingchange = () => { |
| const bc = new PrerenderChannel('test-channel', uid); |
| // Send the result to the test runner page. |
| bc.postMessage({result: 'PASSED'}); |
| }; |
| const bc = new PrerenderChannel('prerender-channel', uid); |
| bc.postMessage('ready for activation'); |
| } |
| } |
| |
| load_as_prerendering_page(); |
| </script> |
| </body> |
| </html> |
| """ |
| |
| def translate_to_js(val: bool) -> str: |
| if isinstance(val, bool): |
| return "true" if val else "false" |
| return "" |
| |
| def main(request, response): |
| response.headers.set(b"Accept-CH", "sec-ch-ua-full-version-list") |
| response.status = 200 |
| |
| # Insert the received hints into script. |
| content = html_template % ( |
| textwrap.dedent( |
| f""" |
| const server_received_bitness = |
| {translate_to_js(b"sec-ch-ua-bitness" in request.headers)}; |
| const server_received_full_version_list = |
| {translate_to_js(b"sec-ch-ua-full-version-list" in |
| request.headers)}; |
| """ |
| ) |
| ) |
| response.content = content.encode("utf-8") |
