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// This script is loaded in HTTP and HTTPS contexts to validate
// PerformanceResourceTiming entries' attributes when reusing connections.
//
// Note: to ensure that we reuse the connection to fetch multiple resources, we
// use the same XMLHttpRequest object throughout an individual test. Although
// it doesn't seem to be specified, each browser tested by WPT will reuse the
// underlying TCP connection with this approach. Pre-establishing the XHR's
// connection helps us to test connection reuse also in browsers that may key
// their connections on the related request's credentials mode.
const connection_reuse_test = (path, follow_on_assertions, test_label) => {
const {on_200, on_304} = follow_on_assertions;
// Make the first request before calling 'attribute_test' so that only the
// second request's PerformanceResourceTiming entry will be interrogated. We
// don't check the first request's PerformanceResourceTiming entry because
// that's not what this test is trying to validate.
const client = new XMLHttpRequest();
const identifier = Math.random();
path = `${path}?tag=${identifier}`;
client.open("GET", path, false);
client.send();
attribute_test(
async () => {
client.open("GET", path + "&same_resource=false", false);
client.send();
// We expect to get a 200 Ok response because we've requested a different
// resource than previous requests.
if (client.status != 200) {
throw new Error(`Got something other than a 200 response. ` +
`client.status: ${client.status}`);
}
}, path, entry => {
invariants.assert_connection_reused(entry);
on_200(entry);
},
`PerformanceResrouceTiming entries need to conform to the spec when a ` +
`distinct resource is fetched over a persistent connection ` +
`(${test_label})`);
attribute_test(
async () => {
client.open("GET", path, false);
client.setRequestHeader("If-None-Match", identifier);
client.send();
// We expect to get a 304 Not Modified response because we've used a
// matching 'identifier' for the If-None-Match header.
if (client.status != 304) {
throw new Error(`Got something other than a 304 response. ` +
`client.status: ${client.status}, response: ` +
`'${client.responseText}'`);
}
}, path, entry => {
invariants.assert_connection_reused(entry);
on_304(entry);
},
`PerformanceResrouceTiming entries need to conform to the spec when the ` +
`resource is cache-revalidated over a persistent connection ` +
`(${test_label})`);
}