Add Async Sample Code

Author: Bill Prin

appengine/urlfetch/async/app.yaml

@@ -0,0 +1,7 @@
+runtime: python27
+api_version: 1
+threadsafe: yes
+
+handlers:
+- url: .*
+  script: rpc.app

appengine/urlfetch/async/rpc.py

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+# Copyright 2016 Google Inc. All Rights Reserved.
+#
+# Licensed 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.
+
+import functools
+import logging
+
+# [START urlfetch-import]
+from google.appengine.api import urlfetch
+# [END urlfetch-import]
+import webapp2
+
+
+class UrlFetchRpcHandler(webapp2.RequestHandler):
+    """ Demonstrates an asynchronous HTTP query using urlfetch"""
+
+    def get(self):
+        # [START urlfetch-rpc]
+        rpc = urlfetch.create_rpc()
+        urlfetch.make_fetch_call(rpc, "http://www.google.com/")
+
+        # ... do other things ...
+        try:
+            result = rpc.get_result()
+            if result.status_code == 200:
+                text = result.content
+                self.response.write(text)
+            else:
+                self.response.status_code = result.status_code
+                logging.error("Error making RPC request")
+        except urlfetch.DownloadError:
+            logging.error("Error fetching URL0")
+        # [END urlfetch-rpc]
+
+
+class UrlFetchRpcCallbackHandler(webapp2.RequestHandler):
+    """ Demonstrates an asynchronous HTTP query with a callback using
+    urlfetch"""
+
+    def get(self):
+        # [START urlfetch-rpc-callback]
+        def handle_result(rpc):
+            result = rpc.get_result()
+            self.response.write(result.content)
+            logging.info("Handling RPC in callback: result {}".format(result))
+
+        urls = ['http://www.google.com',
+                'http://www.github.com',
+                'http://www.travis-ci.org']
+        rpcs = []
+        for url in urls:
+            rpc = urlfetch.create_rpc()
+            rpc.callback = functools.partial(handle_result, rpc)
+            urlfetch.make_fetch_call(rpc, url)
+            rpcs.append(rpc)
+
+        # ... do other things ...
+
+        # Finish all RPCs, and let callbacks process the results.
+
+        for rpc in rpcs:
+            rpc.wait()
+
+        logging.info("Done waiting for RPCs")
+        # [END urlfetch-rpc-callback]
+
+
+app = webapp2.WSGIApplication([
+    ('/', UrlFetchRpcHandler),
+    ('/callback', UrlFetchRpcCallbackHandler),
+], debug=True)

appengine/urlfetch/async/rpc_test.py

@@ -0,0 +1,50 @@
+# Copyright 2016 Google Inc. All rights reserved.
+#
+# Licensed 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.
+
+import mock
+import pytest
+import rpc
+import webtest
+
+
+@pytest.fixture
+def app():
+    return webtest.TestApp(rpc.app)
+
+
+@mock.patch("rpc.urlfetch")
+def test_url_fetch(urlfetch_mock, app):
+    get_result_mock = mock.Mock(
+        return_value=mock.Mock(status_code=200,
+                               content="I'm Feeling Lucky"))
+    urlfetch_mock.create_rpc = mock.Mock(
+        return_value=mock.Mock(get_result=get_result_mock))
+    response = app.get('/')
+    assert response.status_int == 200
+    assert "I'm Feeling Lucky" in response.body
+
+
+@mock.patch("rpc.urlfetch")
+def test_url_post(urlfetch_mock, app):
+    get_result_mock = mock.Mock(
+        return_value=mock.Mock(status_code=200,
+                               content="I'm Feeling Lucky"))
+    urlfetch_mock.create_rpc = mock.Mock(
+      return_value=mock.Mock(get_result=get_result_mock))
+
+    rpc_mock = mock.Mock()
+    urlfetch_mock.create_rpc.return_value = rpc_mock
+
+    app.get('/callback')
+    rpc_mock.wait.assert_called_with()