From b2f43f03cc4e1ff2b9a63c5c52a13cdd56b44377 Mon Sep 17 00:00:00 2001
From: Jon Wayne Parrott <jon.wayne.parrott@gmail.com>
Date: Fri, 15 Apr 2016 10:00:41 -0700
Subject: [PATCH] Refactoring taskqueue sample

Change-Id: I1c78d57979bde942c5a5a6b232ef87cca10944b2
---
 appengine/taskqueue/counter/README.md         |  8 ++
 appengine/taskqueue/counter/application.py    | 74 +++++++++++++++++++
 .../counter/{app.yaml => application.yaml}    |  7 +-
 .../{counter_test.py => application_test.py}  | 22 +++---
 appengine/taskqueue/counter/counter.html      | 15 ----
 appengine/taskqueue/counter/main.py           | 62 ----------------
 appengine/taskqueue/counter/queue.yaml        |  2 +-
 appengine/taskqueue/counter/worker.py         | 44 +++++++++++
 appengine/taskqueue/counter/worker.yaml       |  8 ++
 9 files changed, 149 insertions(+), 93 deletions(-)
 create mode 100644 appengine/taskqueue/counter/application.py
 rename appengine/taskqueue/counter/{app.yaml => application.yaml} (54%)
 rename appengine/taskqueue/counter/{counter_test.py => application_test.py} (62%)
 delete mode 100644 appengine/taskqueue/counter/counter.html
 delete mode 100644 appengine/taskqueue/counter/main.py
 create mode 100644 appengine/taskqueue/counter/worker.py
 create mode 100644 appengine/taskqueue/counter/worker.yaml

diff --git a/appengine/taskqueue/counter/README.md b/appengine/taskqueue/counter/README.md
index 4ccee7143a01..e97ad7df0ed3 100644
--- a/appengine/taskqueue/counter/README.md
+++ b/appengine/taskqueue/counter/README.md
@@ -1,5 +1,13 @@
 # App Engine Task Queue Counter
 
+To run this app locally, specify both `.yaml` files to `dev_appserver.py`:
+
+    dev_appserver.py -A your-app-id application.yaml worker.yaml
+
+To deploy this application, specify both `.yaml` files to `appcfg.py`:
+
+    appcfg.py update -A your-app-id -V 1 application.yaml worker.yaml
+
 <!-- auto-doc-link -->
 These samples are used on the following documentation page:
 
diff --git a/appengine/taskqueue/counter/application.py b/appengine/taskqueue/counter/application.py
new file mode 100644
index 000000000000..dbd27cd849b4
--- /dev/null
+++ b/appengine/taskqueue/counter/application.py
@@ -0,0 +1,74 @@
+# 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.
+
+from google.appengine.api import taskqueue
+from google.appengine.ext import ndb
+import webapp2
+
+
+COUNTER_KEY = 'default counter'
+
+
+class Counter(ndb.Model):
+    count = ndb.IntegerProperty(indexed=False)
+
+
+class MainPageHandler(webapp2.RequestHandler):
+    def get(self):
+        counter = Counter.get_by_id(COUNTER_KEY)
+        count = counter.count if counter else 0
+
+        self.response.write("""
+            Count: {count}<br>
+            <form method="post" action="/enqueue">
+                <label>Increment amount</label>
+                <input name="amount" value="1">
+                <button>Enqueue task</button>
+            </form>
+        """.format(count=count))
+
+
+class EnqueueTaskHandler(webapp2.RequestHandler):
+    def post(self):
+        amount = int(self.request.get('amount'))
+
+        task = taskqueue.add(
+            url='/update_counter',
+            target='worker',
+            params={'amount': amount})
+
+        self.response.write(
+            'Task {} enqueued, ETA {}.'.format(task.name, task.eta))
+
+
+class AsyncEnqueueTaskHandler(webapp2.RequestHandler):
+    def post(self):
+        amount = int(self.request.get('amount'))
+
+        future = taskqueue.add_async(
+            url='/update_counter',
+            target='worker',
+            params={'amount': amount})
+
+        task = future.wait()
+
+        self.response.write(
+            'Task {} enqueued, ETA {}.'.format(task.name, task.eta))
+
+
+app = webapp2.WSGIApplication([
+    ('/', MainPageHandler),
+    ('/enqueue', EnqueueTaskHandler),
+    ('/enqueue_async', EnqueueTaskHandler)
+], debug=True)
diff --git a/appengine/taskqueue/counter/app.yaml b/appengine/taskqueue/counter/application.yaml
similarity index 54%
rename from appengine/taskqueue/counter/app.yaml
rename to appengine/taskqueue/counter/application.yaml
index e2b5e55709c0..b4e5019bd3c9 100644
--- a/appengine/taskqueue/counter/app.yaml
+++ b/appengine/taskqueue/counter/application.yaml
@@ -1,11 +1,8 @@
 runtime: python27
 api_version: 1
 threadsafe: true
+module: default
 
 handlers:
 - url: /.*
-  script: main.app
-
-libraries:
-- name: jinja2
-  version: 2.6
+  script: application.app
diff --git a/appengine/taskqueue/counter/counter_test.py b/appengine/taskqueue/counter/application_test.py
similarity index 62%
rename from appengine/taskqueue/counter/counter_test.py
rename to appengine/taskqueue/counter/application_test.py
index 6facb14b0437..7303e7da30c3 100644
--- a/appengine/taskqueue/counter/counter_test.py
+++ b/appengine/taskqueue/counter/application_test.py
@@ -12,18 +12,20 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from google.appengine.ext import ndb
-import main
+import application
 import webtest
+import worker
 
 
-def test_app(testbed, run_tasks):
-    key_name = 'foo'
+def test_all(testbed, run_tasks):
+    test_app = webtest.TestApp(application.app)
+    test_worker = webtest.TestApp(worker.app)
 
-    app = webtest.TestApp(main.app)
-    app.post('/', {'key': key_name})
-    run_tasks(app)
+    response = test_app.get('/')
+    assert '0' in response.body
 
-    key = ndb.Key('Counter', key_name)
-    counter = key.get()
-    assert counter.count == 1
+    test_app.post('/enqueue', {'amount': 5})
+    run_tasks(test_worker)
+
+    response = test_app.get('/')
+    assert '5' in response.body
diff --git a/appengine/taskqueue/counter/counter.html b/appengine/taskqueue/counter/counter.html
deleted file mode 100644
index a9f6a39d3609..000000000000
--- a/appengine/taskqueue/counter/counter.html
+++ /dev/null
@@ -1,15 +0,0 @@
-<!DOCTYPE html>
-<html>
-<body>
-<form action="/" method="POST">
-  <label for="key">Key:</label><input type="text" name="key" id="key">
-  <input type="submit" value="+1">
-</form>
-<ul>
-{% for counter in counters %}
-<li>
-  {{counter.key.id()|e}}: {{counter.count|e}}
-</li>
-{% endfor %}
-</body>
-</html>
diff --git a/appengine/taskqueue/counter/main.py b/appengine/taskqueue/counter/main.py
deleted file mode 100644
index b25570bf1a1d..000000000000
--- a/appengine/taskqueue/counter/main.py
+++ /dev/null
@@ -1,62 +0,0 @@
-# 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.
-
-# [START all]
-import os
-
-from google.appengine.api import taskqueue
-from google.appengine.ext import ndb
-import jinja2
-import webapp2
-
-
-JINJA_ENV = jinja2.Environment(
-    loader=jinja2.FileSystemLoader(os.path.dirname(__file__)))
-
-
-class Counter(ndb.Model):
-    count = ndb.IntegerProperty(indexed=False)
-
-
-class CounterHandler(webapp2.RequestHandler):
-    def get(self):
-        template_values = {'counters': Counter.query()}
-        counter_template = JINJA_ENV.get_template('counter.html')
-        self.response.out.write(counter_template.render(template_values))
-
-    def post(self):
-        key = self.request.get('key')
-        if key != '':
-            # Add the task to the default queue.
-            taskqueue.add(url='/worker', params={'key': key})
-        self.redirect('/')
-
-
-class CounterWorker(webapp2.RequestHandler):
-    def post(self):  # should run at most 1/s due to entity group limit
-        key = self.request.get('key')
-
-        @ndb.transactional
-        def update_counter():
-            counter = Counter.get_or_insert(key, count=0)
-            counter.count += 1
-            counter.put()
-        update_counter()
-
-
-app = webapp2.WSGIApplication([
-    ('/', CounterHandler),
-    ('/worker', CounterWorker)
-], debug=True)
-# [END all]
diff --git a/appengine/taskqueue/counter/queue.yaml b/appengine/taskqueue/counter/queue.yaml
index 97a10dfa9f53..6b677c17a2f1 100644
--- a/appengine/taskqueue/counter/queue.yaml
+++ b/appengine/taskqueue/counter/queue.yaml
@@ -1,4 +1,4 @@
 queue:
-# Change the refresh rate of the default queue from 5/s to 1/s
+# Change the refresh rate of the default queue from 5/s to 1/s.
 - name: default
   rate: 1/s
diff --git a/appengine/taskqueue/counter/worker.py b/appengine/taskqueue/counter/worker.py
new file mode 100644
index 000000000000..128615b04789
--- /dev/null
+++ b/appengine/taskqueue/counter/worker.py
@@ -0,0 +1,44 @@
+# 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.
+
+from google.appengine.ext import ndb
+import webapp2
+
+
+COUNTER_KEY = 'default counter'
+
+
+class Counter(ndb.Model):
+    count = ndb.IntegerProperty(indexed=False)
+
+
+class UpdateCounterHandler(webapp2.RequestHandler):
+    def post(self):
+        amount = int(self.request.get('amount'))
+
+        # This task should run at most once per second because of the datastore
+        # transaction write throughput.
+        @ndb.transactional
+        def update_counter():
+            counter = Counter.get_or_insert(COUNTER_KEY, count=0)
+            counter.count += amount
+            counter.put()
+
+        update_counter()
+
+
+app = webapp2.WSGIApplication([
+    ('/update_counter', UpdateCounterHandler)
+], debug=True)
+# [END all]
diff --git a/appengine/taskqueue/counter/worker.yaml b/appengine/taskqueue/counter/worker.yaml
new file mode 100644
index 000000000000..4ce72708d8ef
--- /dev/null
+++ b/appengine/taskqueue/counter/worker.yaml
@@ -0,0 +1,8 @@
+runtime: python27
+api_version: 1
+threadsafe: true
+module: worker
+
+handlers:
+- url: /.*
+  script: worker.app