import os def handle_headers(frame, request, response): # Send two Early Hints responses. first_preload = request.GET.first(b"first-preload").decode() link_header_value = "<{}>; rel=preload; as=script".format(first_preload) early_hints = [ (b":status", b"103"), (b"content-security-policy", "script-src 'self' 'unsafe-inline'"), (b"link", link_header_value), ] response.writer.write_raw_header_frame(headers=early_hints, end_headers=True) second_preload = request.GET.first(b"second-preload").decode() link_header_value = "<{}>; rel=preload; as=script".format(second_preload) second_preload_origin = request.GET.first(b"second-preload-origin").decode() csp_value = "script-src 'self' 'unsafe-inline' {}".format(second_preload_origin) early_hints = [ (b":status", b"103"), (b"content-security-policy", csp_value), (b"link", link_header_value), ] response.writer.write_raw_header_frame(headers=early_hints, end_headers=True) response.status = 200 response.headers[b"content-type"] = "text/html" response.write_status_headers() def main(request, response): current_dir = os.path.dirname(os.path.realpath(__file__)) file_path = os.path.join(current_dir, "multiple-early-hints-responses.html") with open(file_path, "r") as f: test_content = f.read() response.writer.write_data(item=test_content, last=True)