Configuration API for PubNub 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()
Properties | Type | Required | Default | 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. |
user_id | String | Yes | 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 theuser_id , 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 | True | 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. |
uuid | 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.
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"
# user ID to be used as a device identifier, won't connect if not set
pn_configuration.user_id = "my_custom_user_id"
# if Access Manager is utilized, client will use this authKey in all restricted
show all 30 linesInitialization
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)
Parameter | Type | Required | Description |
---|---|---|---|
pn_configuration | PNConfiguration | Yes | Goto Configuration for more details. |
custom_event_loop | AbstractEventLoop | No | Whether to use custom instance of Asyncio event loop. |
subscription_manager | EventEngineSubscriptionManager | No | Whether to use the standardized workflows for subscribe and presence. |
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 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
python path/to/your/file.py
Flag | Description |
---|---|
PN_ENABLE_EVENT_ENGINE | Whether to use the standardized workflows for subscribe and presence. |
PN_MAINTAIN_PRESENCE_STATE | Whether the state set should be maintained for the current userId . |
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
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