shared-storage/web-locks-header-batch-update.tentative.https.sub.html

<!doctype html>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/common/utils.js"></script>
<script src="/shared-storage/resources/util.js"></script>
<script src="/fenced-frame/resources/utils.js"></script>

<body>
<script>
'use strict';

promise_test(async t => {
  const worklet = await sharedStorage.createWorklet('resources/simple-module.js');

  const ancestor_key = token();
  const url0 = generateURL("/shared-storage/resources/frame0.html",
                           [ancestor_key]);
  const url1 = generateURL("/shared-storage/resources/frame1.html",
                           [ancestor_key]);

  // Invoke `selectURL()` to perform the following steps:
  // 1. Acquires the lock.
  // 2. Reads the current value at the given key.
  // 3. Waits for 500ms.
  // 4. Sets the shared storage value to the read value appended with the given letter.
  // 5. Releases the lock.
  //
  // After 100ms, send a fetch() request. The response sends the
  // `Shared-Storage-Write` header that:
  // - Acquires the same named lock via the batch `options`
  // - Executes two `append` methods, each appending the same letter.
  //
  // Expected behavior: After both of them finish, the value at the given key
  // should contain the letter repeated three times.
  //
  // This demonstrates that:
  // 1. The `withLock` option is effective, preventing the header batch update
  //    interfering with the "get and set" operation. If the lock were not used,
  //    the final value would likely be a single letter.
  // 2. The header batch update correctly executes all `append` methods within
  //    the batch.
  //
  // Note: This test remains valid even if the header batch update happens
  // outside the critical section protected by the lock within the worklet. The
  // test effectively demonstrates mutual exclusion as long as there's a
  // reasonable chance for the header batch update to occur while the worklet is
  // still running.
  const select_url_result = await worklet.selectURL(
      "get-wait-set-within-lock",
      [{url: url0}, {url: url1}],
      {data: {'key': 'key',
              'lock_name': 'lock1',
              'append_letter': 'a'},
      resolveToConfig: true});

  // Busy wait for 100ms.
  const startWaitTime = Date.now();
  while (Date.now() - startWaitTime < 100) {}

  // After 100ms, send a fetch() request. The response sends the
  // `Shared-Storage-Write` header that:
  // - Acquires the same named lock via the batch `options`
  // - Executes two `append` methods, each appending the same letter.
  const rawUpdatesHeader = 'append;key=key;value=a, append;key=key;value=a, options;with_lock=lock1';
  const updatesHeader = encodeURIComponent(rawUpdatesHeader);
  const updatesUrl =
    `/shared-storage/resources/shared-storage-write.py?write=${updatesHeader}`;

  const response = await fetch(updatesUrl, {sharedStorageWritable: true});
  const sharedStorageWritableHeader = await response.text();
  assert_equals(sharedStorageWritableHeader, "?1");

  attachFencedFrame(select_url_result, 'opaque-ads');
  const result = await nextValueFromServer(ancestor_key);
  assert_equals(result, "frame1_loaded");

  await verifyKeyValueForOrigin('key', 'aaa', location.origin);

  await deleteKeyForOrigin('key', location.origin);
}, 'Test for batch withLock option in the Shared-Storage-Write response header');

</script>
</body>