Configuration API for PubNub Python SDK
Python version support
Python SDK versions 5.0.0 and higher no longer support Python v2.7 and the Twisted and Tornado frameworks. 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 by the end of 2021.
Python complete API reference for building real-time applications on PubNub, including basic usage and sample code.
Configuration
Description
PNConfiguration
instance is storage for user-provided information which describe further PubNub client behavior. Configuration instance contain additional set of properties which allow to perform precise PubNub client configuration.
Method(s)
To create configuration
instance you can use the following function in the Python SDK:
pnconfig = PNConfiguration()
Properties | Type | Required | Defaults | Description |
---|---|---|---|---|
subscribe_key | String | Yes | subscribe_key from Admin Portal. | |
publish_key | String | Optional | None | publish_key from Admin Portal (only required if publishing). |
secret_key | String | Optional | None | secret_key (only required for modifying/revealing access permissions) |
cipher_key | String | Optional | None | If cipher_key is passed, all communications to/from PubNub will be encrypted. |
uuid | String | Yes | UUID to use. You should set a unique UUID to identify the user or the device that connects to PubNub. If you don't set the UUID , you won't be able to connect to PubNub. | |
auth_key | String | Optional | None | If Access Manager is utilized, client will use this authKey in all restricted requests. |
ssl | Boolean | Optional | False | Use SSL . |
connect_timeout | Int | Optional | 5 | How long to wait before giving up connection to client.The value is in seconds. |
subscribe_request_timeout | Int | Optional | 310 | How long to keep the subscribe loop running before disconnect. The value is in seconds. |
non_subscribe_request_timeout | Int | Optional | 10 | On non subscribe operations, how long to wait for server response.The value is in seconds. |
filter_expression | String | Optional | None | Feature to subscribe with a custom filter expression. |
heartbeat_notification_options | PNHeartbeatNotificationOptions | Optional | PNHeartbeatNotificationOptions.FAILURES | Heartbeat notifications, by default, the SDK will alert on failed heartbeats (equivalent to: PNHeartbeatNotificationOptions.FAILURES ). Other options such as all heartbeats ( PNHeartbeatNotificationOptions.ALL ) or no heartbeats (PNHeartbeatNotificationOptions.NONE ) are supported. |
reconnect_policy | PNReconnectionPolicy | Optional | PNReconnectionPolicy.NONE | Set to PNReconnectionPolicy.LINEAR for automatic reconnects. Use option PNReconnectionPolicy.NONE to disable automatic reconnects.Use option PNReconnectionPolicy.EXPONENTIAL to set exponential retry interval. |
origin | String | Optional | ps.pndsn.com | Custom origin if needed. |
suppress_leave_events | Boolean | Optional | False | If True , the client doesn't send presence leave events during the unsubscribe process. |
enable_subscribe | Boolean | Optional | True | You can disable the subscribe loop if you don't need to perform subscribe operations. By default, subscribe loop is enabled and extra threads/loops are started. They should be explicitly stopped by pubnub.stop() method invocation. |
daemon | Boolean | Optional | False | When set to True , spawned thread won't keep the application running after SIGTERM. (ctrl-c from command line, for example) |
disable_token_manager | Boolean | Optional | False | When set to True , the Token Manager System (TMS) will be disabled. Even if there are applicable tokens, no requests will be authorized. |
use_random_initialization_vector | Boolean | Optional | True | When True the initialization vector (IV) is random for all requests (not just for file upload). When False the IV is hard-coded for all requests except for file upload. |
Disabling random initialization vector
Disable random initialization vector (IV) only for backward compatibility (<5.1.0
) with existing applications. Never disable random IV on new applications.
Basic Usage
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.pnconfiguration import PNConfiguration
from pubnub.enums import PNHeartbeatNotificationOptions
pn_configuration = PNConfiguration()
# subscribe_key from Admin Portal
pn_configuration.subscribe_key = "my_subscribe_key" // required
# publish_key from Admin Portal (only required if publishing)
pn_configuration.publish_key = "my_publish_key"
# secret_key (only required for modifying/revealing access permissions)
pn_configuration.secret_key = "my_secret_key"
# if cipher_key is passed, all communicatons to/from pubnub will be encrypted
pn_configuration.cipher_key = "my_cipher_key"
# UUID to be used as a device identifier, won't connect if not set
pn_configuration.uuid = "my_custom_uuid"
# if Access Manager is utilized, client will use this authKey in all restricted
# requests
pn_configuration.auth_key = "my_aut_key"
# use SSL
pn_configuration.ssl = True
# how long to wait before giving up connection to client
pn_configuration.connect_timeout = 100
# how long to keep the subscribe loop running before disconnect
pn_configuration.subscribe_request_timeout = 310
# on non subscribe operations, how long to wait for server response
pn_configuration.non_subscribe_timeout = 300
# PSV2 feature to subscribe with a custom filter expression
pn_configuration.filter_expression = "such=wow"
# heartbeat notifications, by default, the SDK will alert on failed heartbeats.
# other options such as all heartbeats or no heartbeats are supported.
pn_configuration.heartbeat_notification_options = PNHeartbeatNotificationOptions.All
Initialization
Add PubNub to your project using one of the procedures defined under How to Get It
Description
This function is used for initializing the PubNub Client API context. This function must be called before attempting to utilize any API functionality in order to establish account level credentials such as publish_key
and subscribe_key
.
Method(s)
To Initialize
PubNub you can use the following method(s) in the Python SDK:
pubnub = PubNub(my_pnconfig)
Parameter | Type | Required | Description |
---|---|---|---|
pn_configuration | PNConfiguration | Yes | Goto Configuration for more details. |
Basic Usage
Initialize the PubNub client API:
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.pnconfiguration import PNConfiguration
from pubnub.pubnub import PubNub
pnconfig = PNConfiguration()
pnconfig.subscribe_key = "my_subkey"
pnconfig.publish_key = "my_pubkey"
pnconfig.ssl = True
pnconfig.uuid = "my_custom_uuid"
pubnub = PubNub(pnconfig)
Returns
It returns the PubNub instance for invoking PubNub APIs like publish()
, subscribe()
, history()
, here_now()
, etc.
Other Examples
Initialize a non-secure client:
Note
Always set the
UUID
to uniquely identify the user or device that connects to PubNub. ThisUUID
should be persisted, and should remain unchanged for the lifetime of the user or the device. If you don't set theUUID
, you won't be able to connect to PubNub.from pubnub.pnconfiguration import PNConfiguration from pubnub.pubnub import PubNub pnconfig = PNConfiguration() pnconfig.subscribe_key = "my_subkey" pnconfig.publish_key = "my_pubkey" pnconfig.ssl = False pnconfig.uuid = "my_custom_uuid" pubnub = PubNub(pnconfig)
Initialization for a Read-Only client:
In the case where a client will only read messages and never publish to a channel, you can simply omit the
publish_key
when initializing the client:Note
Always set the
UUID
to uniquely identify the user or device that connects to PubNub. ThisUUID
should be persisted, and should remain unchanged for the lifetime of the user or the device. If you don't set theUUID
, you won't be able to connect to PubNub.from pubnub.pnconfiguration import PNConfiguration from pubnub.pubnub import PubNub pnconfig = PNConfiguration() pnconfig.subscribe_key = "my_subkey" pubnub = PubNub(pnconfig)
-
Set a custom
UUID
to identify your users.Note
Always set the
UUID
to uniquely identify the user or device that connects to PubNub. ThisUUID
should be persisted, and should remain unchanged for the lifetime of the user or the device. If you don't set theUUID
, you won't be able to connect to PubNub.from pubnub.pnconfiguration import PNConfiguration from pubnub.pubnub import PubNub pnconfig = PNConfiguration() pnconfig.subscribe_key = 'mySubscribeKey' pnconfig.publish_key = 'myPublishKey' pnconfig.uuid = 'myUniqueUUID' pubnub = PubNub(pnconfig)
Initializing with SSL Enabled:
This examples demonstrates how to enable PubNub Transport Layer Encryption with
SSL
. Just initialize the client withssl
set toTrue
. The hard work is done, now the PubNub API takes care of the rest. Just subscribe and publish as usual and you are good to go.Note
Always set the
UUID
to uniquely identify the user or device that connects to PubNub. ThisUUID
should be persisted, and should remain unchanged for the lifetime of the user or the device. If you don't set theUUID
, you won't be able to connect to PubNub.from pubnub.pnconfiguration import PNConfiguration from pubnub.pubnub import PubNub pnconfig = PNConfiguration() pnconfig.subscribe_key = "my_subkey" pnconfig.publish_key = "my_pubkey" pnconfig.ssl = True pnconfig.uuid = "my_custom_uuid" pubnub = PubNub(pnconfig)
- Initializing with Access Manager: Requires Access Manager add-onRequires that the Access Manager add-on is enabled for your key. See this page on enabling add-on features on your keys:
https://support.pubnub.com/hc/en-us/articles/360051974791-How-do-I-enable-add-on-features-for-my-keys-Note
Anyone with the
secret_key
can grant and revoke permissions to your app. Never let yoursecret_key
be discovered, and to only exchange it / deliver it securely. Only use thesecret_key
on secure server-side platforms.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.For applications that will administer PAM permissions, the API is initialized with the
secret_key
as in the following example:Note
Always set the
UUID
to uniquely identify the user or device that connects to PubNub. ThisUUID
should be persisted, and should remain unchanged for the lifetime of the user or the device. If you don't set theUUID
, you won't be able to connect to PubNub.from pubnub.pnconfiguration import PNConfiguration from pubnub.pubnub import PubNub pnconfig = PNConfiguration() pnconfig.subscribe_key = "my_subkey" pnconfig.publish_key = "my_pubkey" pnconfig.secret_key = "my_secretkey" pnconfig.uuid = "my_custom_uuid" pnconfig.ssl = True pubnub = PubNub(pnconfig)
Now that the pubnub object is instantiated the client will be able to access the PAM functions. The pubnub object will use the
secret_key
to sign all PAM messages to the PubNub Network.
Event Listeners
Description
You can be notified of connectivity status, message and presence notifications via the listeners.
Listeners should be added before calling the method.
Adding Listeners
from pubnub.callbacks import SubscribeCallback
from pubnub.enums import PNOperationType, PNStatusCategory
class MySubscribeCallback(SubscribeCallback):
def message(self, pubnub, message):
print("Message channel: %s" % message.channel)
print("Message subscription: %s" % message.subscription)
print("Message timetoken: %s" % message.timetoken)
print("Message payload: %s" % message.message)
print("Message publisher: %s" % message.publisher)
def presence(self, pubnub, presence):
# Can be join, leave, state-change, timeout, or interval
print("Presence event: %s" % presence.event)
# The channel to which the message was published
print("Presence channel: %s" % presence.channel)
# Number of users subscribed to the channel
print("Presence occupancy: %s" % presence.occupancy)
# User state
print("Presence state: %s" % presence.state)
# Channel group or wildcard subscription match, if any
print("Presence subscription: %s" % presence.subscription)
# UUID to which this event is related
print("Presence UUID: %s" % presence.uuid)
# Publish timetoken
print("Presence timestamp: %s" % presence.timestamp)
# Current timetoken
print("Presence timetoken: %s" % presence.timetoken)
# List of users that have joined the channel (if event is 'interval')
joined = presence.join
# List of users that have left the channel (if event is 'interval')
left = presence.leave
# List of users that have timed-out off the channel (if event is 'interval')
timed_out = presence.timeout
def status(self, pubnub, status):
# 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
# This usually occurs if subscribe temporarily fails but reconnects. This means
# there was an error but there is no longer any issue
elif status.category == PNStatusCategory.PNDisconnectedCategory:
pass
# This is the expected category for an unsubscribe. This means there
# was no error in unsubscribing from everything
elif status.category == PNStatusCategory.PNUnexpectedDisconnectCategory:
pass
# This is usually an issue with the internet connection, this is an error, handle
# appropriately retry will be called automatically
elif status.category == PNStatusCategory.PNAccessDeniedCategory:
pass
# This means that PAM does not allow this client to subscribe to this
# channel and channel group configuration. This is another explicit error
else:
pass
# This is usually an issue with the internet connection, this is an error, handle appropriately
# retry will be called automatically
elif status.operation == PNOperationType.PNSubscribeOperation:
# Heartbeat operations can in fact have errors, so it is important to check first for an error.
# For more information on how to configure heartbeat notifications through the status
# PNObjectEventListener callback, consult http://www.pubnub.com/docs/sdks/python/api-reference/configuration#configuration
if status.is_error():
pass
# There was an error with the heartbeat operation, handle here
else:
pass
# Heartbeat operation was successful
else:
pass
# Encountered unknown status type
def signal(self, pubnub, signal):
print("Signal channel: %s" % signal.channel)
print("Signal subscription: %s" % signal.subscription)
print("Signal timetoken: %s" % signal.timetoken)
print("Signal payload: %s" % signal.message)
print("Signal publisher: %s" % signal.publisher)
def message_action(self, pubnub, message_action):
print("Message action type: %s" % message_action.type)
print("Message action value: %s" % message_action.value)
print("Message action uuid: %s" % message_action.uuid)
print("Message action action_timetoken: %s" % message_action.action_timetoken)
print("Message action message_timetoken: %s" % message_action.message_timetoken)
pubnub.add_listener(MySubscribeCallback())
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):
pass
def message(self, pubnub, message):
pass
def signal(self, pubnub, signal):
pass
disconnect_listener = HandleDisconnectsCallback()
pubnub.add_listener(disconnect_listener)
Listener status events
Category | Description |
---|---|
PNTimeoutCategory | Failure to establish a connection to PubNub due to a timeout. |
PNBadRequestCategory | The server responded with a bad response error because the request is malformed. |
PNNetworkIssuesCategory | A 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. |
PNReconnectedCategory | The SDK was able to reconnect to PubNub. |
PNConnectedCategory | SDK subscribed with a new mix of channels. This is fired every time the channel or channel group mix changes. |
PNUnexpectedDisconnectCategory | Previously started subscribe loop did fail and at this moment client disconnected from real-time data channels. |
PNUnknownCategory | Returned when the subscriber gets a non-200 HTTP response code from the server. |
SubscribeListener
should not be used with high-performance sections of your app.
Filter Expression
Requires Stream Controller add-onRequires that the Stream Controller add-on is enabled for your key. See this page on enabling add-on features on your keys:
https://support.pubnub.com/hc/en-us/articles/360051974791-How-do-I-enable-add-on-features-for-my-keys-
Description
Stream filtering allows a subscriber to apply a filter to only receive messages that satisfy the conditions of the filter. The message filter is set by the subscribing client(s) but it is applied on the server side thus preventing unwanted messages (those that do not meet the conditions of the filter) from reaching the subscriber.
To set/get filters you can use the following methods. To learn more about filtering, refer to the Publish Messages documentation.
Method(s)
Set Filter Expression
The property accepts a string
.
Get Filter Expression
The property returns a string
Basic Usage
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.pnconfiguration import PNConfiguration
pnconfig = PNConfiguration()
pnconfig.filter_expression = "such=wow"
filter = pnconfig.filter_expression