PubNub Python-Twisted SDK 7.0.0

Unsupported SDK

PubNub no longer supports this SDK, but you are welcome to contribute.

Python version support

Python SDK versions 5.0.0 and higher no longer support Python v2.7 and the Twisted framework. If you require support for any of these, use SDK version 4.8.1.

Note that PubNub will stop supporting versions of Python lower than 3.7 at the end of 2021.

Deprecated

NOTICE: Based on current web trends and our own usage data, PubNub's Python Twisted SDK is deprecated as of May 1, 2019. Deprecation means we will no longer be updating the Python Twisted SDK but will continue to support users currently using it. Please feel free to use our other Python SDK offerings as they will continue to be supported and maintained. If you would like to use the Python Twisted SDK specifically, we would love to work with you on keeping this project alive!

Get Code: pip

The simplest way to get started is to install PubNub Python SDK via pip:

pip install 'pubnub>=7.0.0'

Get Code: git

git clone https://github.com/pubnub/python

Get Code: Source

https://github.com/pubnub/python

View Supported Platforms

Hello World

Add PubNub to your project using one of the procedures defined under How to Get It.

Dependencies

  • PyOpenSSL
  • Service-Identity

Include the Python SDK in your code

from pubnub.pubnub_twisted import PubNubTwisted
Note

Always set the UUID to uniquely identify the user or device that connects to PubNub. This UUID should be persisted, and should remain unchanged for the lifetime of the user or the device. If you don't set the UUID, you won't be able to connect to PubNub.

from pubnub.enums import PNStatusCategory
from pubnub.pubnub_twisted import PubNubTwisted as PubNub
from pubnub.pnconfiguration import PNConfiguration
from twisted.internet import reactor
from pubnub.callbacks import SubscribeCallback

def main():
pnconf = PNConfiguration()
pnconf.subscribe_key = 'demo'
pnconf.publish_key = 'demo'
pnconf.uuid = "my_custom_uuid"

pubnub = PubNub(pnconf)

def my_publish_callback(result, status):
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Copy and paste examples

In addition to the Hello World sample code, we also provide some copy and paste snippets of common API functions:

Init

Instantiate a new Pubnub instance. Only the subscribe_key is mandatory. Also include publish_key if you intend to publish from this instance, and the secret_key if you wish to perform Access Manager administrative operations from this Python-Twisted instance.

Important

For security reasons you should only include the secret-key on a highly secured server. The secret-key is only required for granting rights using our Access Manager.

When you init with secret_key, you get root permissions for the Access Manager. With this feature you don't have to grant access to your servers to access channel data. The servers get all access on all channels.

Note

Always set the UUID to uniquely identify the user or device that connects to PubNub. This UUID should be persisted, and should remain unchanged for the lifetime of the user or the device. If you don't set the UUID, you won't be able to connect to PubNub.

from pubnub.pubnub_twisted import PubNubTwisted
from pubnub.pnconfiguration import PNConfiguration

pnconfig = PNConfiguration()
pnconfig.subscribe_key = "my_subkey"
pnconfig.publish_key = "my_pubkey"
pnconfig.ssl = False
pnconfig.uuid = "my_custom_uuid"
pubnub = PubNubTwisted(pnconfig)

Listeners

Adding Listeners

from pubnub.callbacks import SubscribeCallback

class MySubscribeCallback(SubscribeCallback):
def status(self, pubnub, status):
pass
# The status object returned is always related to subscribe but could contain
# information about subscribe, heartbeat, or errors
# use the operationType to switch on different options
if status.operation == PNOperationType.PNSubscribeOperation \
or status.operation == PNOperationType.PNUnsubscribeOperation:
if status.category == PNStatusCategory.PNConnectedCategory:
pass
# This is expected for a subscribe, this means there is no error or issue whatsoever
elif status.category == PNStatusCategory.PNReconnectedCategory:
pass
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Removing Listeners

my_listener = MySubscribeCallback()

pubnub.add_listener(my_listener)

# some time later
pubnub.remove_listener(my_listener)

Handling Disconnects

from pubnub.callbacks import SubscribeCallback
from pubnub.enums import PNStatusCategory

class HandleDisconnectsCallback(SubscribeCallback):
def status(self, pubnub, status):
if status.category == PNStatusCategory.PNUnexpectedDisconnectCategory:
# internet got lost, do some magic and call reconnect when ready
pubnub.reconnect()
elif status.category == PNStatusCategory.PNTimeoutCategory:
# do some magic and call reconnect when ready
pubnub.reconnect()
else:
logger.debug(status)

def presence(self, pubnub, presence):
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Listener status events

CategoryDescription
PNTimeoutCategoryFailure to establish a connection to PubNub due to a timeout.
PNBadRequestCategoryThe server responded with a bad response error because the request is malformed.
PNNetworkIssuesCategoryA subscribe event experienced an exception when running. The SDK isn't able to reach the PubNub Data Stream Network. This may be due to many reasons, such as: the machine or device isn't connected to the internet; the internet connection has been lost; your internet service provider is having trouble; or, perhaps the SDK is behind a proxy.
PNReconnectedCategoryThe SDK was able to reconnect to PubNub.
PNConnectedCategorySDK subscribed with a new mix of channels. This is fired every time the channel or channel group mix changes.
PNUnexpectedDisconnectCategoryPreviously started subscribe loop did fail and at this moment client disconnected from real-time data channels.
PNUnknownCategoryReturned when the subscriber gets a non-200 HTTP response code from the server.

Time

Call time() to verify the client connectivity to the origin:

d = pubnub.time().deferred()
d.addCallback(my_callback)

Subscribe

Subscribe (listen on) a channel:

pubnub.subscribe().channels('my_channel').execute()
Note

The response of the call is handled by adding a Listener. Please see the Listeners section for more details. Listeners should be added before calling the method.

Publish

Publish a message to a channel:

@gen.coroutine
def publish_snippet():
def publish_callback(result, status):
if not status.is_error():
envelope = result
pass # Message successfully published to specified channel.
else:
pass # Handle message publish error. Check 'category' property to find out possible issue
# because of which request did fail.
# Request can be resent using: [status retry];

pubnub.publish().channel('such_channel').message(['hello', 'there']).pn_async(publish_callback)

Here Now

Get occupancy of who's here now on the channel by UUID:

Note

Requires you to enable the Presence add-on for your key. Refer to the How do I enable add-on features for my keys? knowledge base article for details on enabling features.

envelope = yield pubnub.here_now()\
.channels("my_channel", "demo")\
.include_uuids(True)\
.future()

if envelope.status.is_error():
# handle error
return

for channel_data in envelope.result.channels:
print("---")
print("channel: %s" % channel_data.channel_name)
print("occupancy: %s" % channel_data.occupancy)

print("occupants: %s" % channel_data.channel_name)
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Presence

Subscribe to real-time Presence events, such as join, leave, and timeout, by UUID. Setting the presence attribute to a callback will subscribe to presents events on my_channel:

Note

Requires you to enable the Presence add-on for your key. Refer to the How do I enable add-on features for my keys? knowledge base article for details on enabling features.

pubnub.subscribe()\
.channels("my_channel")\
.with_presence()\
.execute()
Note

The response of the call is handled by adding a Listener. Please see the Listeners section for more details. Listeners should be added before calling the method.

History

Retrieve published messages from archival storage:

Note

Requires that the Message Persistence add-on is enabled for your key. See how to enable add-on features for your keys.

envelope = yield pubnub.history()\
.channel("history_channel")\
.count(100)\
.future()

Unsubscribe

Stop subscribing (listening) to a channel:

pubnub.unsubscribe().channels("my_channel").execute()
Note

The response of the call is handled by adding a Listener. Please see the Listeners section for more details. Listeners should be added before calling the method.