Update web-platform-tests to revision b'ee6da9d71d0268d7fdb04e8e5b26858f46ee0cc4'

tests/wpt/web-platform-tests/common/dispatcher/dispatcher.js

@@ -0,0 +1,189 @@
+// Define an universal message passing API. It works cross-origin and across
+// browsing context groups.
+const dispatcher_path = "/common/dispatcher/dispatcher.py";
+const dispatcher_url = new URL(dispatcher_path, location.href).href;
+
+// Return a promise, limiting the number of concurrent accesses to a shared
+// resources to |max_concurrent_access|.
+const concurrencyLimiter = (max_concurrency) => {
+  let pending = 0;
+  let waiting = [];
+  return async (task) => {
+    pending++;
+    if (pending > max_concurrency)
+      await new Promise(resolve => waiting.push(resolve));
+    let result = await task();
+    pending--;
+    waiting.shift()?.();
+    return result;
+  };
+}
+
+// Wait for a random amount of time in the range [10ms,100ms].
+const randomDelay = () => {
+  return new Promise(resolve => setTimeout(resolve, 10 + 90*Math.random()));
+}
+
+// Sending too many requests in parallel causes congestion. Limiting it improves
+// throughput.
+//
+// Note: The following table has been determined on the test:
+// ../cache-storage.tentative.https.html
+// using Chrome with a 64 core CPU / 64GB ram, in release mode:
+// ┌───────────┬───┬───┬───┬───┬───┬───┬───┬───┬───┬───┬───┬────┐
+// │concurrency│ 1 │ 2 │ 3 │ 4 │ 5 │ 6 │ 10│ 15│ 20│ 30│ 50│ 100│
+// ├───────────┼───┼───┼───┼───┼───┼───┼───┼───┼───┼───┼───┼────┤
+// │time (s)   │ 54│ 38│ 31│ 29│ 26│ 24│ 22│ 22│ 22│ 22│ 34│ 36 │
+// └───────────┴───┴───┴───┴───┴───┴───┴───┴───┴───┴───┴───┴────┘
+const limiter = concurrencyLimiter(6);
+
+const send = async function(uuid, message) {
+  await limiter(async () => {
+    // Requests might be dropped. Retry until getting a confirmation it has been
+    // processed.
+    while(1) {
+      try {
+        let response = await fetch(dispatcher_url + `?uuid=${uuid}`, {
+          method: 'POST',
+          body: message
+        })
+        if (await response.text() == "done")
+          return;
+      } catch (fetch_error) {}
+      await randomDelay();
+    };
+  });
+}
+
+const receive = async function(uuid) {
+  while(1) {
+    let data = "not ready";
+    try {
+      data = await limiter(async () => {
+        let response = await fetch(dispatcher_url + `?uuid=${uuid}`);
+        return await response.text();
+      });
+    } catch (fetch_error) {}
+
+    if (data == "not ready") {
+      await randomDelay();
+      continue;
+    }
+
+    return data;
+  }
+}
+
+// Returns an URL. When called, the server sends toward the `uuid` queue the
+// request headers. Useful for determining if something was requested with
+// Cookies.
+const showRequestHeaders = function(origin, uuid) {
+  return origin + dispatcher_path + `?uuid=${uuid}&show-headers`;
+}
+
+// Same as above, except for the response is cacheable.
+const cacheableShowRequestHeaders = function(origin, uuid) {
+  return origin + dispatcher_path + `?uuid=${uuid}&cacheable&show-headers`;
+}
+
+// This script requires
+// - `/common/utils.js` for `token()`.
+
+// Represents a remote executor. For more detailed explanation see `README.md`.
+class RemoteContext {
+  // `uuid` is a UUID string that identifies the remote context and should
+  // match with the `uuid` parameter of the URL of the remote context.
+  constructor(uuid) {
+    this.context_id = uuid;
+  }
+
+  // Evaluates the script `expr` on the executor.
+  // - If `expr` is evaluated to a Promise that is resolved with a value:
+  //   `execute_script()` returns a Promise resolved with the value.
+  // - If `expr` is evaluated to a non-Promise value:
+  //   `execute_script()` returns a Promise resolved with the value.
+  // - If `expr` throws an error or is evaluated to a Promise that is rejected:
+  //   `execute_script()` returns a rejected Promise with the error's
+  //   `message`.
+  //   Note that currently the type of error (e.g. DOMException) is not
+  //   preserved.
+  // The values should be able to be serialized by JSON.stringify().
+  async execute_script(fn, args) {
+    const receiver = token();
+    await this.send({receiver: receiver, fn: fn.toString(), args: args});
+    const response = JSON.parse(await receive(receiver));
+    if (response.status === 'success') {
+      return response.value;
+    }
+
+    // exception
+    throw new Error(response.value);
+  }
+
+  async send(msg) {
+    return await send(this.context_id, JSON.stringify(msg));
+  }
+};
+
+class Executor {
+  constructor(uuid) {
+    this.uuid = uuid;
+
+    // If `suspend_callback` is not `null`, the executor should be suspended
+    // when there are no ongoing tasks.
+    this.suspend_callback = null;
+
+    this.execute();
+  }
+
+  // Wait until there are no ongoing tasks nor fetch requests for polling
+  // tasks, and then suspend the executor and call `callback()`.
+  // Navigation from the executor page should be triggered inside `callback()`,
+  // to avoid conflict with in-flight fetch requests.
+  suspend(callback) {
+    this.suspend_callback = callback;
+  }
+
+  resume() {
+  }
+
+  async execute() {
+    while(true) {
+      if (this.suspend_callback !== null) {
+        this.suspend_callback();
+        this.suspend_callback = null;
+        // Wait for `resume()` to be called.
+        await new Promise(resolve => this.resume = resolve);
+
+        // Workaround for https://crbug.com/1244230.
+        // Without this workaround, the executor is resumed and the fetch
+        // request to poll the next task is initiated synchronously from
+        // pageshow event after the page restored from BFCache, and the fetch
+        // request promise is never resolved (and thus the test results in
+        // timeout) due to https://crbug.com/1244230. The root cause is not yet
+        // known, but setTimeout() with 0ms causes the resume triggered on
+        // another task and seems to resolve the issue.
+        await new Promise(resolve => setTimeout(resolve, 0));
+
+        continue;
+      }
+
+      const task = JSON.parse(await receive(this.uuid));
+
+      let response;
+      try {
+        const value = await eval(task.fn).apply(null, task.args);
+        response = JSON.stringify({
+          status: 'success',
+          value: value
+        });
+      } catch(e) {
+        response = JSON.stringify({
+          status: 'exception',
+          value: e.message
+        });
+      }
+      await send(task.receiver, response);
+    }
+  }
+}