Support WebSocket in WebRequest API.

chrome/test/data/extensions/api_test/webrequest/test_websocket.js

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+function getEchoTestURL(port) {
+  return "ws://localhost:" + port + "/echo-with-no-extension";
+}
+
+// Tries to: open a WebSocket, write a test message to it, close it. Verifies
+// that all the necessary events are triggered if |expectedToConnect|, otherwise
+// makes sure WebSocket terminates with an error.
+function testWebSocketConnection(url, expectedToConnect = true) {
+  var ws = new WebSocket(url);
+  var MESSAGE = "test message";

[Devlin, 2017/02/14 01:21:38]

single quotes in js.  Also, typically prefer kMessage instead of MESSAGE.

[pkalinnikov, 2017/02/14 13:49:51]

Done.

+
+  var connectionOpenExpected;

[Devlin, 2017/02/14 01:21:38]

why not just something like:
var keepalive = chrome.test.callbackAdded();

and then use assert[False|True](expectedToConnect)?

[pkalinnikov, 2017/02/14 13:49:51]

Indeed.

+  var connectionErrorExpected;
+  if (expectedToConnect)
+    connectionOpenExpected = chrome.test.callbackAdded()
+  else
+    connectionErrorExpected = chrome.test.callbackAdded();
+
+  ws.onerror = function(error) {
+    chrome.test.log("WebSocket error: " + error);

[Devlin, 2017/02/14 01:21:38]

single quotes (whole file)

[pkalinnikov, 2017/02/14 13:49:51]

Done.

+    chrome.test.assertFalse(expectedToConnect);
+    connectionErrorExpected();
+  };
+  ws.onmessage = function(messageEvent) {
+    chrome.test.log("Message received: " + messageEvent.data);
+    chrome.test.assertTrue(expectedToConnect);
+    chrome.test.assertEq(MESSAGE, messageEvent.data);
+    ws.close();
+  };
+  ws.onclose = function(event) {
+    chrome.test.log("WebSocket closed.");
+    chrome.test.assertEq(expectedToConnect, event.wasClean);
+  }
+
+  ws.onopen = function() {
+    chrome.test.log("WebSocket opened.");
+    chrome.test.assertTrue(expectedToConnect);
+    connectionOpenExpected();
+    ws.send(MESSAGE);
+  };
+}
+
+chrome.tabs.getCurrent(function(tab) {
+  runTestsForTab([
+    // Opens a WebSocket connection, writes a message to it, and closes the
+    // connection. WebRequest API should observe the entire handshake.
+    function handshakeSucceeds() {
+      var webSocketUrl = getEchoTestURL(testWebSocketPort);
+      expect(
+        [  //events
+          { label: "onBeforeRequest",
+            event: "onBeforeRequest",
+            details: {
+              url: webSocketUrl,
+              type: "other",
+              frameUrl: "unknown frame URL",
+            },
+          },
+          { label: "onBeforeSendHeaders",
+            event: "onBeforeSendHeaders",
+            details: {
+              url: webSocketUrl,
+              type: "other",
+            },
+          },
+          { label: "onSendHeaders",
+            event: "onSendHeaders",
+            details: {
+              url: webSocketUrl,
+              type: "other",
+            },
+          },
+          { label: "onHeadersReceived",
+            event: "onHeadersReceived",
+            details: {
+              url: webSocketUrl,
+              type: "other",
+              statusCode: 101,
+              statusLine: "HTTP/1.1 101 Switching Protocols",
+            },
+          },
+          { label: "onResponseStarted",
+            event: "onResponseStarted",
+            details: {
+              url: webSocketUrl,
+              type: "other",
+              ip: "127.0.0.1",
+              fromCache: false,
+              statusCode: 101,
+              statusLine: "HTTP/1.1 101 Switching Protocols",
+            },
+          },
+          { label: "onCompleted",
+            event: "onCompleted",
+            details: {
+              url: webSocketUrl,
+              type: "other",
+              fromCache: false,
+              statusCode: 101,
+              statusLine: "HTTP/1.1 101 Switching Protocols",
+            }
+          },
+        ],
+        [  // event order
+          ["onBeforeRequest", "onBeforeSendHeaders", "onSendHeaders",
+          "onHeadersReceived", "onResponseStarted", "onCompleted"]
+        ],
+        {urls: ["<all_urls>"]},  // filter
+        ["blocking"]  // extraInfoSpec
+      );
+      testWebSocketConnection(webSocketUrl);
+    },
+
+    // Tries to open a WebSocket connection, with a blocking handler that
+    // cancels the request. The connection will not establish.
+    function handshakeRequestCancelled() {
+      var webSocketUrl = getEchoTestURL(testWebSocketPort);
+      expect(
+        [  // events
+          { label: "onBeforeRequest",
+            event: "onBeforeRequest",
+            details: {
+              url: webSocketUrl,
+              type: "other",
+              frameUrl: "unknown frame URL",
+            },
+            retval: {cancel: true}
+          },
+          // Cancelling is considered an error.
+          { label: "onErrorOccurred",
+            event: "onErrorOccurred",
+            details: {
+              url: webSocketUrl,
+              type: "other",
+              fromCache: false,
+              error: "net::ERR_BLOCKED_BY_CLIENT"
+            }
+          },
+        ],
+        [  // event order
+          ["onBeforeRequest", "onErrorOccurred"]
+        ],
+        {urls: ["<all_urls>"]},  // filter
+        ["blocking"]  // extraInfoSpec
+      );
+      testWebSocketConnection(webSocketUrl, false);
+    },

[Devlin, 2017/02/14 01:21:38]

redirect test?

[pkalinnikov, 2017/02/14 13:49:51]

I tried doing redirect, and it didn't work (see my previous response to
Dominic's comments).

I see 2 options:
1. Disallow redirecting WS from WebRequest API.
2. As Adam Rice pointed out, although server redirects of WS requests are
prohibited for security reasons, it would be possible to make an exception for
synthetic redirects from extensions.

What do you think is the right way to go? I would probably go with whatever is
the simplest, which is probably the option 1.

[Devlin, 2017/02/14 15:55:24]

I think that disallowing redirect is fine, especially since we're not sure
there's a demand for it and it's more inline with the traditional web socket
behavior.  But I think we should explicitly test that behavior so that it's
deterministic, and add a comment explaining it.

[pkalinnikov, 2017/02/15 19:15:00]

Added redirect test.

+  ], tab);
+});