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The dependencies in the root react-chat-components folder:Go to the samples/react/getting-started folder.Open the app in the code editor, navigate to the src/getting-started.tsx file and replacemyPublishKey and mySubscribeKey with your own Publish and Subscribe Keys from the keyset onthe Admin Portal. To associate a sender/current user with the PubNub messages, it's required toconfigure the userId parameter that refers to your user ID in the database. If you wish, modifythe default value for the chat user.publishKey: "myPublishKey",subscribeKey: "mySubscribeKey",userId: "myFirstUser",userIdFor simplicity, the getting started app sets a static userId. However, if you implement chat in your app, you should generate a userId per user, device, and server and reuse it for their lifetime. Using separate User IDs in real-life apps is particularly important as it impacts your overall billing and the way your app works.The complete getting-started.tsx file looks as follows:/* Imports PubNub JavaScript and React SDKs to create and access PubNub instance across your app. *//* Imports the required PubNub Chat Components to easily create chat apps with PubNub. */import React from "react";import PubNub from "pubnub";import { PubNubProvider } from "pubnub-react";import { Chat, MessageList, MessageInput } from "@pubnub/react-chat-components";/* Creates and configures your PubNub instance. Be sure to replace "myPublishKey" and "mySubscribeKey" with your own keyset. If you wish, modify the default "myFirstUser" userId value for the chat user. */const pubnub = new PubNub({ publishKey: "myPublishKey", subscribeKey: "mySubscribeKey", userId: "myFirstUser",});const currentChannel = "Default";show all 33 linesBack in the terminal, run the app on the dev server.Send your first message​Open the dev server in the browser at the default address and send your first message. The messages will pile up on the screen as you send them.To verify that the app is connected to the PubNub Network, mock a real-live chat conversation with myFirstUser. Open localhost in a new browser tab, send a message from one tab and reply to it from another.Next steps​With a React app running, find out how you can expand and customize it. Check out our:Sample group chat (preview and GitHub sources).On this pagePrerequisitesStepsRun the chat appSend your first messageNext steps

Introduce the listeners and send the subscribe() call, so place the relevant code in the appropriate places within your code.subscription = pubnub.channel('example').subscription()# add a listenersubscription.on_message = lambda message: print(f'Message from {message.publisher}: {message.message}')subscription.subscribe()time.sleep(1)# publish publish_result = pubnub.publish().channel("example").message("Hello from PubNub Python SDK").sync()For more information, refer to the Publish and Subscribe section of the PubNub Python SDK API documentation, and to Publishing a Message.Putting it all together​Your App class should now look similar to the following:import osimport timefrom pubnub.pnconfiguration import PNConfigurationfrom pubnub.pubnub import PubNub, SubscribeListener# this will print out the subscription status to consoleclass Listener(SubscribeListener): def status(self, pubnub, status): print(f'Status: \n{status.category.name}')# here we create configuration for our pubnub instanceconfig = PNConfiguration()config.subscribe_key = 'demo'config.publish_key = 'demo'show all 34 linesNow, run your app to see if you did everything correctly. You should see the "Hello from PubNub Python SDK" message in the console.Congratulations! You've just subscribed to a channel and sent your first message.Walkthrough​Instead of focusing on the order in which you wrote the code, let's focus on the order in which it runs. The app you just created does a few things:Configures a PubNub connectionAdds the status and message event listenersSubscribes to a channelPublishes a messageConfiguring PubNub​The following code is the minimum configuration you need to send and receive messages with PubNub. For more information, refer to the Configuration section of the SDK documentation.from pubnub.pnconfiguration import PNConfigurationfrom pubnub.pubnub import PubNubpnconfig = PNConfiguration()pnconfig.subscribe_key = 'mySubscribeKey'pnconfig.publish_key = 'myPublishKey'pnconfig.user_id = "my_custom_user_id"pubnub = PubNub(pnconfig)Add event listeners​Listeners help your app react to events and messages. You can implement custom app logic to respond to each type of message or event.You added two listeners to the app: status and message. Status listens for status events and when it receives an event of type PNConnectedCategory, it prints the status to the console. The other listener, message, listens for incoming messages on a particular channel. When it receives a message, the app simply prints the received message.# this will replace default SubscribeListener with thing that will print out messages to consoleclass Listener(SubscribeListener): def status(self, pubnub, status): print(f'Status: \n{status.category.name}')pubnub.add_listener(Listener())# creates a subscriptionsubscription = pubnub.channel('example').subscription()subscription.on_message = lambda message: print(f'Message from {message.publisher}: {message.message}')For more information, refer to the Listeners section of the SDK documentation.Publishing and subscribing​PubNub uses the Publish/Subscribe model for real-time communication. This model involves two essential parts:Channels are transient paths over which your data is transmittedMessages contain the data you want to transmit to one or more recipientsWhen you want to receive messages

This page outlines the steps to follow to create a simple Hello, World application with PubNub. This covers the basics of integrating PubNub in your application: setting up a connection to PubNub, and sending and receiving messages (like in a live chat).PubNub accountDownload the SDKSend messagesPubNub account​Sign in or create an account to create an app on the Admin Portal and get the keys to use in your application.When you create a new app, the first set of keys is generated automatically, but a single app can have as many keysets as you like. We recommend that you create separate keysets for production and test environments.Download the SDK​SDK versionAlways use the latest SDK version to have access to the newest features and avoid security vulnerabilities, bugs, and performance issues.Download the SDK from any of the following sources:Use pip​To integrate PubNub into your project using pip:pip install 'pubnub>=10.2.0'Get the source code​ the supported platforms here.Configure PubNub​In the IDE of your choice, create a new App class with the following content. This is the minimum configuration you need to send and receive messages with PubNub.Make sure to replace myPublishKey and mySubscribeKey with your app's publish and subscribe keys from the Admin Portal.from pubnub.pnconfiguration import PNConfigurationfrom pubnub.pubnub import PubNubconfig = PNConfiguration()config.subscribe_key = '_mySubscribeKey_'config.publish_key = '_myPublishKey_'config.user_id = 'example'For more information, refer to the Configuration section of the PubNub Python SDK API documentation.Add event listeners​Listeners help your app react to events and messages. You can implement custom app logic to respond to each type of message or event.Copy the following code to configure your app to print out the connection status to the console. Additionally, we added a second listener that prints the content of every received message.# this will replace default SubscribeListener with thing that will print out messages to consoleclass Listener(SubscribeListener): def status(self, pubnub, status): print(f'Status: \n{status.category.name}')pubnub.add_listener(Listener())# creates a subscriptionsubscription = pubnub.channel('example').subscription()subscription.on_message = lambda message: print(f'Message from {message.publisher}: {message.message}')For more information, refer to the Listeners section of the SDK documentation.Publish and subscribe​To receive messages sent to a particular channel, you subscribe to it. When you publish a message to a channel, PubNub delivers that message to everyone subscribed to that channel.In this app, a simple "Hello from PubNub Python SDK" string is published to the "example" channel.To subscribe to real-time updates, you must create a subscription or a subscription set and send a subscribe() call.It is best to define the subscription before you