pubnub
PubNub JavaScript SDK (V4)
This is the official PubNub JavaScript SDK repository.
PubNub takes care of the infrastructure and APIs needed for the realtime communication layer of your application. Work on your app's logic and let PubNub handle sending and receiving data across the world in less than 100ms.
Get keys
You will need the publish and subscribe keys to authenticate your app. Get your keys from the Admin Portal.
Tutorial Video
Watch Getting Started with PubNub JS SDK on Dashcam
Configure PubNub
Integrate the JavaScript SDK into your project:
- use
npm:npm install pubnub - or download one of our builds from our CDN:
- use
Configure your keys:
pubnub = new PubNub({ publishKey: 'myPublishKey', subscribeKey: 'mySubscribeKey', userId: 'myUniqueUserId', });
Add event listeners
// create a subscription from a channel entity
const channel = pubnub.channel('my_channel');
const subscription = channel.subscription();
subscription.subscribe();
// Event-specific listeners
subscription.onMessage = (messageEvent) => { console.log("Message event: ", messageEvent); };
subscription.onPresence = (presenceEvent) => { console.log("Presence event: ", presenceEvent); };
subscription.onMessage = (messageEvent) => { console.log("Message event: ", messageEvent); };
subscription.onPresence = (presenceEvent) => { console.log("Presence event: ", presenceEvent); };
subscription.onSignal = (signalEvent) => { console.log("Signal event: ", signalEvent); };
subscription.onObjects = (objectsEvent) => { console.log("Objects event: ", objectsEvent); };
subscription.onMessageAction = (messageActionEvent) => { console.log("Message Action event: ", messageActionEvent); };
subscription.onFile = (fileEvent) => { console.log("File event: ", fileEvent); };
// Generic listeners
subscription.addListener({
// Messages
message: function (m) {
const channelName = m.channel; // Channel on which the message was published
const channelGroup = m.subscription; // Channel group or wildcard subscription match (if exists)
const pubTT = m.timetoken; // Publish timetoken
const msg = m.message; // Message payload
const publisher = m.publisher; // Message publisher
},
// Presence
// requires a subscription with presence
presence: function (p) {
const action = p.action; // Can be join, leave, state-change, or timeout
const channelName = p.channel; // Channel to which the message belongs
const occupancy = p.occupancy; // Number of users subscribed to the channel
const state = p.state; // User state
const channelGroup = p.subscription; // Channel group or wildcard subscription match, if any
const publishTime = p.timestamp; // Publish timetoken
const timetoken = p.timetoken; // Current timetoken
const uuid = p.uuid; // UUIDs of users who are subscribed to the channel
},
// Signals
signal: function (s) {
const channelName = s.channel; // Channel to which the signal belongs
const channelGroup = s.subscription; // Channel group or wildcard subscription match, if any
const pubTT = s.timetoken; // Publish timetoken
const msg = s.message; // Payload
const publisher = s.publisher; // Message publisher
},
// App Context
objects: (objectEvent) => {
const channel = objectEvent.channel; // Channel to which the event belongs
const channelGroup = objectEvent.subscription; // Channel group
const timetoken = objectEvent.timetoken; // Event timetoken
const publisher = objectEvent.publisher; // UUID that made the call
const event = objectEvent.event; // Name of the event that occurred
const type = objectEvent.type; // Type of the event that occurred
const data = objectEvent.data; // Data from the event that occurred
},
// Message Reactions
messageAction: function (ma) {
const channelName = ma.channel; // Channel to which the message belongs
const publisher = ma.publisher; // Message publisher
const event = ma.event; // Message action added or removed
const type = ma.data.type; // Message action type
const value = ma.data.value; // Message action value
const messageTimetoken = ma.data.messageTimetoken; // Timetoken of the original message
const actionTimetoken = ma.data.actionTimetoken; // Timetoken of the message action
},
// File Sharing
file: function (event) {
const channelName = event.channel; // Channel to which the file belongs
const channelGroup = event.subscription; // Channel group or wildcard subscription match (if exists)
const publisher = event.publisher; // File publisher
const timetoken = event.timetoken; // Event timetoken
const message = event.message; // Optional message attached to the file
const fileId = event.file.id; // File unique id
const fileName = event.file.name;// File name
const fileUrl = event.file.url; // File direct URL
}
});Publish/subscribe
const channel = pubnub.channel('my_channel');
const subscription = channel.subscription();
subscription.subscribe();
try {
const result = await pubnub.publish({
message: {
such: "object",
},
channel: "my_channel",
sendByPost: false, // true to send via post
storeInHistory: false, //override default Message Persistence options
meta: {
cool: "meta",
}, // publish extra meta with the request
});
} catch (status) {
console.log(status);
}Documentation
Support
If you need help or have a general question, contact support@pubnub.com.