safaridriver: add new command to change getUserMedia() behavior for mock devices

As part of this feature, we introduce new endpoints to get and set session permissions. For example, it
can control whether a getUserMedia() request for a mock media stream will be allowed or denied.

Since this is the first Safari-specific endpoint, add a custom RemoteConnection subclass
so that extra commands can be added in. Hook it up in the subclass of WebDriver.

This adds two commands:

driver.get_permission(permission_name) -> True, False, None
driver.set_permission(permission_name, True | False)

For convenience, supported values of permission_name are enumerated by the Permission object.

These commands map, respectively, to the following endpoints and request/response payloads:

GET /session/$sessionId/apple/permissions

Request payload:
None

Response payload:
{
    "permissions": {
        "getUserMedia": true,
        ...
    }
}

Notes: values for all session permissions are returned, whether or not they have previously been set.

--

POST /session/$sessionId/apple/permissions

Request payload:
{
    "permissions": [
        "getUserMedia": true,
        ...
    ]
}

Response payload:
None

Notes: can update multiple session permissions simultaneously. Any omitted permission names are unaffected.

Author: burg

py/selenium/webdriver/safari/permissions.py

@@ -0,0 +1,28 @@
+# Licensed to the Software Freedom Conservancy (SFC) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The SFC licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+"""
+The Permission implementation.
+"""
+
+
+class Permission(object):
+    """
+    Set of supported permissions.
+    """
+
+    GET_USER_MEDIA = "getUserMedia"

py/selenium/webdriver/safari/remote_connection.py

@@ -0,0 +1,26 @@
+# Licensed to the Software Freedom Conservancy (SFC) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The SFC licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+from selenium.webdriver.remote.remote_connection import RemoteConnection
+
+
+class SafariRemoteConnection(RemoteConnection):
+    def __init__(self, remote_server_addr, keep_alive=True):
+        RemoteConnection.__init__(self, remote_server_addr, keep_alive)
+
+        self._commands["GET_PERMISSIONS"] = ('GET', '/session/$sessionId/apple/permissions')
+        self._commands["SET_PERMISSIONS"] = ('POST', '/session/$sessionId/apple/permissions')

py/selenium/webdriver/safari/webdriver.py

@@ -23,7 +23,7 @@
 from selenium.webdriver.common.desired_capabilities import DesiredCapabilities
 from selenium.webdriver.remote.webdriver import WebDriver as RemoteWebDriver
 from .service import Service
-
+from .remote_connection import SafariRemoteConnection
 
 class WebDriver(RemoteWebDriver):
     """
@@ -50,10 +50,13 @@ def __init__(self, port=0, executable_path="/usr/bin/safaridriver", reuse_servic
         if not reuse_service:
             self.service.start()
 
+        executor = SafariRemoteConnection(remote_server_addr=self.service.service_url)
+
         RemoteWebDriver.__init__(
             self,
-            command_executor=self.service.service_url,
+            command_executor=executor,
             desired_capabilities=desired_capabilities)
+
         self._is_remote = False
 
     def quit(self):
@@ -68,3 +71,31 @@ def quit(self):
         finally:
             if not self._reuse_service:
                 self.service.stop()
+
+    # safaridriver extension commands. The canonical command support matrix is here:
+    # https://developer.apple.com/library/content/documentation/NetworkingInternetWeb/Conceptual/WebDriverEndpointDoc/Commands/Commands.html
+
+    # First available in Safari 11.1 and Safari Technology Preview 41.
+    def set_permission(self, permission, value):
+        if not isinstance(value, bool):
+            raise WebDriverException("Value of a session permission must be set to True or False.")
+
+        payload = {}
+        payload[permission] = value
+        self.execute("SET_PERMISSIONS", {"permissions": payload})
+
+    # First available in Safari 11.1 and Safari Technology Preview 41.
+    def get_permission(self, permission):
+        payload = self.execute("GET_PERMISSIONS")["value"]
+        permissions = payload["permissions"]
+        if not permissions:
+            return None
+
+        if permission not in permissions:
+            return None
+
+        value = permissions[permission]
+        if not isinstance(value, bool):
+            return None
+
+        return value