Configuration API for Python-Asyncio SDK

Python-asyncio complete API reference for building real-time applications on PubNub, including basic usage and sample code.

Configuration

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-asyncio SDK:

pnconfig = PNConfiguration()

* required

Parameter	Description
subscribe_key * Type: String Default: n/a	subscribe_key from Admin Portal.
publish_key Type: String Default: None	publish_key from Admin Portal (only required if publishing).
secret_key Type: String Default: None	secret_key (only required for modifying/revealing access permissions)
cipher_key Type: String Default: None	If cipher_key is passed, all communications to/from PubNub will be encrypted.
user_id * Type: String Default: n/a	user_id to use. You should set a unique user_id to identify the user or the device that connects to PubNub. It's a UTF-8 encoded string of up to 92 alphanumeric characters. If you don't set the user_id, you won't be able to connect to PubNub.
auth_key Type: String Default: None	If Access Manager is utilized, client will use this authKey in all restricted requests.
ssl Type: Boolean Default: True	Use SSL.
connect_timeout Type: Int Default: 5	How long to wait before giving up connection to client.The value is in seconds.
subscribe_request_timeout Type: Int Default: 310	How long to keep the subscribe loop running before disconnect. The value is in seconds.
non_subscribe_request_timeout Type: Int Default: 10	On non subscribe operations, how long to wait for server response.The value is in seconds.
filter_expression Type: String Default: None	Feature to subscribe with a custom filter expression.
heartbeat_notification_options Type: PNHeartbeatNotificationOptions Default: 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 Type: PNReconnectionPolicy Default: 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 Type: String Default: ps.pndsn.com	Custom origin if needed.
suppress_leave_events Type: Boolean Default: False	If True, the client doesn't send presence leave events during the unsubscribe process.
enable_subscribe Type: Boolean Default: 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 Type: Boolean Default: 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 Type: Boolean Default: 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 Type: Boolean Default: 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.
uuid * Type: String Default: n/a	This parameter is deprecated, use user_id instead. 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.

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

Required User ID

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

Reference code

This example is a self-contained code snippet ready to be run. It includes necessary imports and executes methods with console logging. Use it as a reference when working with other examples in this document.

import os
from pubnub.pnconfiguration import PNConfiguration
from pubnub.enums import PNHeartbeatNotificationOptions


# Configuration for PubNub instance
pn_configuration = PNConfiguration()

# Set configuration values
pn_configuration.subscribe_key = os.getenv('PUBNUB_SUBSCRIBE_KEY', 'demo')  # required
pn_configuration.publish_key = os.getenv('PUBNUB_PUBLISH_KEY', 'demo')  # only required if publishing
pn_configuration.secret_key = os.getenv('PUBNUB_SECRET_KEY', 'my_secret_key')  # optional
pn_configuration.user_id = os.getenv('PUBNUB_USER_ID', 'my_custom_user_id')  # must be set
pn_configuration.auth_key = os.getenv('PUBNUB_AUTH_KEY', 'my_auth_key')  # optional
pn_configuration.ssl = True

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Initialization

Add PubNub to your project using one of the procedures defined above.

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-asyncio SDK:

pubnub = PubNubAsyncio(pn_configuration, custom_event_loop, subscription_manager, *, custom_request_handler)

* required

Parameter	Description
pn_configuration * Type: PNConfiguration	Goto Configuration for more details.
custom_event_loop Type: AbstractEventLoop	Whether to use custom instance of Asyncio event loop.
subscription_manager Type: EventEngineSubscriptionManager	Whether to use the standardized workflows for subscribe and presence.
custom_request_handler Type: subclass of BaseRequestHandler	The optional custom HTTP request handler. For more information, refer to Custom request handler. Default is AsyncHttpxRequestHandler.

Environment variables

You can only turn on certain features using environment variables through inline declaration:

PN_ENABLE_EVENT_ENGINE=True PN_MAINTAIN_PRESENCE_STATE=True PUBNUB_ASYNC_REQUEST_HANDLER=AsyncAiohttpRequestHandler python path/to/your/file.py 

or by exporting it to your system, and then running script normally:

export PN_ENABLE_EVENT_ENGINE=True
export PN_MAINTAIN_PRESENCE_STATE=True
export PUBNUB_ASYNC_REQUEST_HANDLER=AsyncAiohttpRequestHandler

python path/to/your/file.py

Flag	Description
PN_ENABLE_EVENT_ENGINE	Whether to use the recommended standardized workflows for subscribe and presence, optimizing how the SDK internally handles these operations and which statuses it emits.
PN_MAINTAIN_PRESENCE_STATE	Whether the custom presence state information set using pubnub.set_state() should be sent every time the SDK sends a subscribe call.
PUBNUB_ASYNC_REQUEST_HANDLER	The library for sending HTTP requests.

To Initialize PubNub you can use the following method(s) in the Python SDK:

pubnub = PubNub(pn_configuration, custom_request_handler)

* required

Parameter	Description
pn_configuration * Type: PNConfiguration Default: n/a	The configuration object. For more details, refer to Configuration.
custom_request_handler Type: subclass of BaseRequestHandler Default: HttpxRequestHandler	The optional custom HTTP request handler. For more information, refer to Custom request handler.

Custom request handler

The custom_request_handler optional configuration option allows you to select the library for sending HTTP requests.

If you don't specify this parameter, the Python SDK first checks the value of the PUBNUB_ASYNC_REQUEST_HANDLER environment variable. If you don't set the variables or their value is not a subclass of BaseRequestHandler, the PubNub Python SDK defaults to AsyncHttpxRequestHandler.

Class	Description
AsyncAiohttpRequestHandler	Python SDK asynchronous requests handler based on the requests HTTP library.
AsyncHttpxRequestHandler	Python SDK asynchronous requests handler based on the httpx HTTP library.

Basic Usage

Initialize the PubNub client API

Required User ID

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

from pubnub.pnconfiguration import PNConfiguration
from pubnub.pubnub_asyncio import PubNubAsyncio

pnconfig = PNConfiguration()
pnconfig.subscribe_key = "my_subkey"
pnconfig.publish_key = "my_pubkey"
pnconfig.ssl = True
pnconfig.user_id = "my_custom_user_id"
pubnub = PubNubAsyncio(pnconfig)

Returns

It returns the PubNub instance for invoking PubNub APIs like publish(), subscribe(), history(), here_now(), etc.

Other Examples

Use a custom request handler

You can set a custom request handler by specifying one of the available request handlers during the initialization of the PubNub client.

Required User ID

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

from pubnub.pnconfiguration import PNConfiguration
from pubnub.pubnub_asyncio import PubNubAsyncio
from pubnub.request_handlers.async_aiohttp import AsyncAiohttpRequestHandler

pnconfig = PNConfiguration()
pnconfig.subscribe_key = "my_subkey"
pnconfig.publish_key = "my_pubkey"
pnconfig.ssl = True
pnconfig.user_id = "my_custom_user_id"
pubnub = PubNubAsyncio(pnconfig)


pubnub = PubNub(pnconfig, custom_request_handler=AsyncAiohttpRequestHandler)

Initialize a non-secure client

Required User ID

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

from pubnub.pnconfiguration import PNConfiguration
from pubnub.pubnub_asyncio import PubNubAsyncio

pnconfig = PNConfiguration()
pnconfig.subscribe_key = "my_subkey"
pnconfig.publish_key = "my_pubkey"
pnconfig.ssl = False
pnconfig.user_id = "my_custom_user_id"
pubnub = PubNubAsyncio(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:

Required User ID

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

from pubnub.pnconfiguration import PNConfiguration
from pubnub.pubnub_asyncio import PubNubAsyncio

pnconfig = PNConfiguration()
pnconfig.subscribe_key = "my_subkey"

pubnub = PubNubAsyncio(pnconfig)

Use a custom User ID

Set a custom user_id to identify your users.

Required User ID

Always set the user_id to uniquely identify the user or device that connects to PubNub. This user_id should be persisted, and should remain unchanged for the lifetime of the user or the device. If you don't set the user_id, 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.user_id = "my_custom_user_id"

pubnub = PubNub(pnconfig)

Initializing with SSL Enabled

This examples demonstrates how to enable PubNub Transport Layer Encryption with SSL. Just initialize the client with ssl set to True. 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.

Required User ID

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

from pubnub.pnconfiguration import PNConfiguration
from pubnub.pubnub_asyncio import PubNubAsyncio

pnconfig = PNConfiguration()
pnconfig.subscribe_key = "my_subkey"
pnconfig.publish_key = "my_pubkey"
pnconfig.ssl = True
pnconfig.user_id = "my_custom_user_id"
pubnub = PubNubAsyncio(pnconfig)

Initializing with Access Manager

Requires Access Manager add-on

This method requires that the Access Manager add-on is enabled for your key in the Admin Portal. Read the support page on enabling add-on features on your keys.

Secure your secret_key

Anyone with the secret_key can grant and revoke permissions to your app. Never let your secret_key be discovered, and to only exchange it / deliver it securely. Only use the secret_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 Access Manager permissions, the API is initialized with the secret_key as in the following example:

Required User ID

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

from pubnub.pnconfiguration import PNConfiguration
from pubnub.pubnub_asyncio import PubNubAsyncio

pnconfig = PNConfiguration()
pnconfig.subscribe_key = "my_subkey"
pnconfig.publish_key = "my_pubkey"
pnconfig.secret_key = "my_secretkey"
pnconfig.user_id = "my_custom_user_id"
pnconfig.ssl = True

pubnub = PubNubAsyncio(pnconfig)

Now that the pubnub object is instantiated the client will be able to access the Access Manager functions. The pubnub object will use the secret_key to sign all Access Manager messages to the PubNub Network.

Initializing with a custom event loop

Required User ID

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

from pubnub.pnconfiguration import PNConfiguration
from pubnub.pubnub_asyncio import PubNubAsyncio

pnconfig = PNConfiguration()
pnconfig.subscribe_key = "my_subkey"
pnconfig.publish_key = "my_pubkey"

pubnub = PubNubAsyncio(pnconfig, custom_event_loop=my_event_loop)

Event Listeners

PubNub SDKs provide several sources for real-time updates:

• The PubNub client can receive updates from all subscriptions: all channels, channel groups, channel metadata, and users.
• The Subscription object can receive updates only for the particular object for which it was created: channel, channel group, channel metadata, or user.
• The SubscriptionsSet object can receive updates for all objects for which a list of subscription objects was created.

To facilitate working with those real-time update sources, PubNub SDKs use local representations of server entities that allow you to subscribe and add handlers on a per-entity basis. For more information, refer to Publish & Subscribe.

Filter Expression

Requires Stream Controller add-on

This method requires that the Stream Controller add-on is enabled for your key in the Admin Portal. Read the support page on enabling add-on features on your keys.

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 or get message 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

Set Filter Expression

Required User ID

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

from pubnub.pnconfiguration import PNConfiguration

pnconfig = PNConfiguration()
pnconfig.filter_expression = "such=wow"

Get Filter Expression

filter = pnconfig.filter_expression