Python-Tornado Configuration API Reference for Realtime Apps
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-Tornado complete API reference for building Realtime 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-Tornado 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 SDK generated uuid
UUID
to use. You should set a uniqueUUID
to identify the user or the device that connects to PubNub.
Allowing the SDK to generate a randomUUID
can result in significant billing impacts, particularly on an MAU pricing plan.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_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 optionPNReconnectionPolicy.NONE
to disable automatic reconnects.Use optionPNReconnectionPolicy.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 bypubnub.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.
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. Not setting the UUID
can significantly impact your billing if your account uses the Monthly Active Users (MAUs) based pricing model, and can also lead to unexpected behavior if you have Presence enabled.
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, a default UUID is generated
# if not passed
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_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-Tornado SDK:
pubnub = PubNubTornado(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. Not setting the UUID
can significantly impact your billing if your account uses the Monthly Active Users (MAUs) based pricing model, and can also lead to unexpected behavior if you have Presence enabled.
from pubnub.pnconfiguration import PNConfiguration
from pubnub.pubnub_tornado import PubNubTornado
pnconfig = PNConfiguration()
pnconfig.subscribe_key = "my_subkey"
pnconfig.publish_key = "my_pubkey"
pnconfig.ssl = True
pnconfig.uuid = "my_custom_uuid"
pubnub = PubNubTornado(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. Not setting theUUID
can significantly impact your billing if your account uses the Monthly Active Users (MAUs) based pricing model, and can also lead to unexpected behavior if you have Presence enabled.from pubnub.pnconfiguration import PNConfiguration from pubnub.pubnub_tornado import PubNubTornado pnconfig = PNConfiguration() pnconfig.subscribe_key = 'my_subscribe_key' pnconfig.publish_key = 'my_publish_key' pnconfig.secret_key = 'my_secret_key' pnconfig.uuid = "my_custom_uuid" pnconfig.ssl = False pubnub = PubNubTornado(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. Not setting theUUID
can significantly impact your billing if your account uses the Monthly Active Users (MAUs) based pricing model, and can also lead to unexpected behavior if you have Presence enabled.from pubnub.pnconfiguration import PNConfiguration from pubnub.pubnub_tornado import PubNubTornado pnconfig = PNConfiguration() pnconfig.subscribe_key = "my_subkey" pubnub = PubNubTornado(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. Not setting theUUID
can significantly impact your billing if your account uses the Monthly Active Users (MAUs) based pricing model, and can also lead to unexpected behavior if you have Presence enabled.from pubnub.pnconfiguration import PNConfiguration from pubnub.pubnub_tornado import PubNubTornado pnconfig = PNConfiguration() pnconfig.subscribe_key = 'mySubscribeKey' pnconfig.publish_key = 'myPublishKey' pnconfig.uuid = 'myUniqueUUID' pubnub = PubNubTornado(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. Not setting theUUID
can significantly impact your billing if your account uses the Monthly Active Users (MAUs) based pricing model, and can also lead to unexpected behavior if you have Presence enabled.from pubnub.pnconfiguration import PNConfiguration from pubnub.pubnub_tornado import PubNubTornado pnconfig = PNConfiguration() pnconfig.subscribe_key = "my_subkey" pnconfig.publish_key = "my_pubkey" pnconfig.ssl = True pnconfig.uuid = "my_custom_uuid" pubnub = PubNubTornado(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. Not setting theUUID
can significantly impact your billing if your account uses the Monthly Active Users (MAUs) based pricing model, and can also lead to unexpected behavior if you have Presence enabled.from pubnub.pnconfiguration import PNConfiguration from pubnub.pubnub_tornado import PubNubTornado 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 = PubNubTornado(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.
Filter Expression
Requires Stream Controller add-on Requires 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. Not setting the UUID
can significantly impact your billing if your account uses the Monthly Active Users (MAUs) based pricing model, and can also lead to unexpected behavior if you have Presence enabled.
from pubnub.pnconfiguration import PNConfiguration
pnconfig = PNConfiguration()
pnconfig.filter_expression = "such=wow"
filter = pnconfig.filter_expression