Sketch 'gcloud.pubsub' API.

Author: tseaver

docs/conf.py

@@ -30,6 +30,7 @@
 extensions = [
     'sphinx.ext.autodoc',
     'sphinx.ext.autosummary',
+    'sphinx.ext.doctest',
     'sphinx.ext.todo',
     'sphinx.ext.viewcode',
 ]

docs/index.rst

@@ -14,6 +14,7 @@
   storage-blobs
   storage-buckets
   storage-acl
+  pubsub-api
 
 
 Getting started

docs/pubsub-api.rst

@@ -0,0 +1,251 @@
+``gcloud.pubsub`` API
+=====================
+
+Connection / Authorization
+--------------------------
+
+- Inferred defaults used to create connection if none configured explicitly:
+
+  - credentials (derived from GAE / GCE environ if present).
+
+  - ``project_id`` (derived from GAE / GCE environ if present).
+
+  - ``scopes``
+
+
+Manage topics for a project
+---------------------------
+
+Create a new topic for the default project:
+
+.. doctest::
+
+   >>> from gcloud.pubsub.topic import Topic
+   >>> topic = Topic('topic_name')
+   >>> topic.create()  # API request
+
+Create a new topic for an explicit project:
+
+.. doctest::
+
+   >>> from gcloud.pubsub.topic import Topic
+   >>> topic = Topic('topic_name', project_id='my.project')
+   >>> topic.create()  # API request
+
+Check for the existance of a topic:
+
+.. doctest::
+
+   >>> from gcloud.pubsub.topic import Topic
+   >>> topic = Topic('topic_name')
+   >>> topic.exists()  # API request
+   True
+
+List topics for the default project:
+
+.. doctest::
+
+   >>> from gcloud import pubsub
+   >>> [topic.name for topic in pubsub.list_topics()]  # API request
+   ['topic_name']
+
+List topics for an explicit project:
+
+.. doctest::
+
+   >>> from gcloud import pubsub
+   >>> topics = pubsub.list_topics(project_id='my.project')  # API request
+   >>> [topic.name for topic in topics]
+   ['topic_name']
+
+Delete a topic:
+
+.. doctest::
+
+   >>> from gcloud.pubsub.topic import Topic
+   >>> topic = Topic('topic_name')
+   >>> topic.delete()  # API request
+
+
+Publish messages to a topic
+---------------------------
+
+Publish a single message to a topic, without attributes:
+
+.. doctest::
+
+   >>> from gcloud.pubsub.topic import Topic
+   >>> topic = Topic('topic_name')
+   >>> topic.publish('this is the message_payload')  # API request
+   <message_id>
+
+Publish a single message to a topic, with attributes:
+
+.. doctest::
+
+   >>> from gcloud.pubsub.topic import Topic
+   >>> topic = Topic('topic_name')
+   >>> topic.publish('this is another message_payload',
+   ...               attr1='value1', attr2='value2')  # API request
+   <message_id>
+
+Publish a set of messages to a topic (as a single request):
+
+.. doctest::
+
+   >>> from gcloud.pubsub.topic import Topic
+   >>> topic = Topic('topic_name')
+   >>> with topic as batch:
+   ...     topic.publish('this is the first message_payload')
+   ...     topic.publish('this is the second message_payload',
+   ...                   attr1='value1', attr2='value2')
+   >>> batch
+   [<message_id1>, <message_id2>]
+
+.. note::
+
+   The only API request happens during the ``__exit__()`` of the topic
+   used as a context manager.
+
+
+Manage subscriptions to topics
+------------------------------
+
+Create a new pull subscription for a topic:
+
+.. doctest::
+
+   >>> from gcloud.pubsub.topic import Topic
+   >>> from gcloud.pubsub.subscription import Subscription
+   >>> topic = Topic('topic_name')
+   >>> subscription = Subscription('subscription_name', topic)
+   >>> subscription.create()  # API request
+
+Create a new pull subscription for a topic with a non-default ACK deadline:
+
+.. doctest::
+
+   >>> from gcloud.pubsub.topic import Topic
+   >>> from gcloud.pubsub.subscription import Subscription
+   >>> topic = Topic('topic_name')
+   >>> subscription = Subscription('subscription_name', ack_deadline=90)
+   >>> subscription.create()  # API request
+
+Create a new push subscription for a topic:
+
+.. doctest::
+
+   >>> ENDPOINT = 'https://example.com/hook'
+   >>> from gcloud.pubsub.topic import Topic
+   >>> from gcloud.pubsub.subscription import Subscription
+   >>> topic = Topic('topic_name')
+   >>> subscription = Subscription('subscription_name', push_endpoint=ENDPOINT)
+   >>> subscription.create()  # API request
+
+Check for the existence of a subscription:
+
+.. doctest::
+
+   >>> from gcloud.pubsub.topic import Topic
+   >>> from gcloud.pubsub.subscription import Subscription
+   >>> topic = Topic('topic_name')
+   >>> subscription = Subscription('subscription_name', topic)
+   >>> subscription.exists()  # API request
+   True
+
+Convert a pull subscription to push:
+
+.. doctest::
+
+   >>> ENDPOINT = 'https://example.com/hook'
+   >>> from gcloud.pubsub.topic import Topic
+   >>> from gcloud.pubsub.subscription import Subscription
+   >>> topic = Topic('topic_name')
+   >>> subscription = Subscription('subscription_name', topic)
+   >>> subscription.modify_push_configuration(push_endpoint=ENDPOINT)  # API request
+
+Convert a push subscription to pull:
+
+.. doctest::
+
+   >>> ENDPOINT = 'https://example.com/hook'
+   >>> from gcloud.pubsub.topic import Topic
+   >>> topic = Topic('topic_name')
+   >>> subscription = Subscription('subscription_name', topic,
+   ...                             push_endpoint=ENDPOINT)
+   >>> subscription.modify_push_configuration(push_endpoint=None)  # API request
+
+List subscriptions for a topic:
+
+.. doctest::
+
+   >>> from gcloud.pubsub.topic import Topic
+   >>> topic = Topic('topic_name')
+   >>> subscriptions = topic.list_subscriptions()  # API request
+   >>> [subscription.name for subscription in subscriptions]
+   ['subscription_name']
+
+Delete a subscription:
+
+.. doctest::
+
+   >>> from gcloud.pubsub.topic import Topic
+   >>> from gcloud.pubsub.subscription import Subscription
+   >>> topic = Topic('topic_name')
+   >>> subscription = Subscription('subscription_name', topic)
+   >>> subscription.delete()  # API request
+
+
+Pull messages from a subscription
+---------------------------------
+
+Fetch pending messages for a pull subscription
+
+.. note::
+
+   The messages will have been ACKed already.
+
+.. doctest::
+
+   >>> from gcloud.pubsub.topic import Topic
+   >>> from gcloud.pubsub.subscription import Subscription
+   >>> topic = Topic('topic_name')
+   >>> subscription = Subscription('subscription_name', topic)
+   >>> with topic:
+   ...     topic.publish('this is the first message_payload')
+   ...     topic.publish('this is the second message_payload',
+   ...                   attr1='value1', attr2='value2')
+   >>> messages = subscription.pull()  # API request
+   >>> [message.id for message in messages]
+   [<message_id1>, <message_id2>]
+   >>> [message.data for message in messages]
+   ['this is the first message_payload', 'this is the second message_payload']
+   >>> [message.attrs for message in messages]
+   [{}, {'attr1': 'value1', 'attr2': 'value2'}]
+
+Fetch a limited number of pending messages for a pull subscription:
+
+.. doctest::
+
+   >>> from gcloud.pubsub.topic import Topic
+   >>> from gcloud.pubsub.subscription import Subscription
+   >>> topic = Topic('topic_name')
+   >>> subscription = Subscription('subscription_name', topic)
+   >>> with topic:
+   ...     topic.publish('this is the first message_payload')
+   ...     topic.publish('this is the second message_payload',
+   ...                   attr1='value1', attr2='value2')
+   >>> [message.id for message in subscription.pull(max_messages=1)]
+   [<message_id1>]
+
+Fetch messages for a pull subscription without blocking (none pending):
+
+.. doctest::
+
+   >>> from gcloud.pubsub.topic import Topic
+   >>> from gcloud.pubsub.subscription import Subscription
+   >>> topic = Topic('topic_name')
+   >>> subscription = Subscription('subscription_name', topic)
+   >>> [message.id for message in subscription.pull(return_immediately=True)]
+   []
+