Azure Communication Call Automation client library for JavaScript

This package contains a JavaScript SDK for Azure Communication Call Automation. Call Automation provides developers the ability to build server-based, intelligent call workflows, and call recording for voice and PSTN channels.

Overview of Call Automation | Product documentation

Getting started

Prerequisites

An Azure subscription.
An existing Communication Services resource. If you need to create the resource, you can use the Azure Portal, the Azure PowerShell, or the Azure CLI.

Installing

npm install @azure/communication-call-automation

Browser support

JavaScript Bundle

To use this client library in the browser, first you need to use a bundler. For details on how to do this, please refer to our bundling documentation.

Key concepts

Name	Description
CallAutomationClient	`CallAutomationClient` is the primary interface for developers using this client library. It can be used to initiate calls by `createCall` or `answerCall`.
CallConnection	`CallConnection` represents a ongoing call. Once the call is established with `createCall` or `answerCall`, further actions can be performed for the call, such as `transfer` or `addParticipant`.
CallMedia	`CallMedia` can be used to do media related actions, such as `play`, to play media file. This can be retrieved from established `CallConnection`.
CallRecording	`CallRecording` can be used to do recording related actions, such as `startRecording`. This can be retrieved from `CallAutomationClient`.
Callback Events	Callback events are events sent back during duration of the call. It gives information and state of the call, such as `CallConnected`. `CallbackUrl` must be provided during `createCall` and `answerCall`, and callback events will be sent to this url. You can use `callAutomationEventParser` to parse these events when it arrives.
Incoming Call Event	When incoming call happens (that can be answered with `answerCall`), incoming call eventgrid event will be sent. This is different from Callback events above, and should be setup on Azure portal. See Incoming Call for detail.
CallAutomationEventProcessor	`CallAutomationEventProcessor` is a convinient way to handle mid-call callback events such as `CallConnected`. This will ensure correlation between call and events more easily. See below example for its usage.

Examples

Initialize CallAutomationClient

import { CallAutomationClient } from '@azure/communication-call-automation';
import { DefaultAzureCredential } from "@azure/identity"; 

// Your unique Azure Communication service endpoint
const credential = new DefaultAzureCredential(); 
const endpointUrl = '<ENDPOINT>' 
const callAutomationClient = new CallAutomationClient(endpointUrl, credential);

Create Call

import { CommunicationUserIdentifier } from "@azure/communication-common";
import { CallAutomationClient, CallInvite } from '@azure/communication-call-automation';

// target endpoint for ACS User
const target: CommunicationUserIdentifier = {
  communicationUserId:
    "8:acs:...",
}

// make invitation
const callInvite: CallInvite = {
   targetParticipant:target
};

// callback url to recieve callback events
const callbackUrl = "https://<MY-EVENT-HANDLER-URL>/events";

// send out the invitation, creating call
const response = callAutomationClient.createCall(callInvite, callbackUrl);

Play Media

// from callconnection of response above, play media of media file
const myFile: FileSource = { uri: "https://<FILE-SOURCE>/<SOME-FILE>.wav" }
const response = callConnection.getCallMedia().playToAll(myFile);

Handle Mid-Connection callback events

To easily handle mid-connection events, Call Automation's SDK provides easier way to handle these events. Take a look at CallAutomationEventProcessor. This will ensure correlation between call and events more easily.

const eventProcessor: CallAutomationEventProcessor = await callAutomationClient.getEventProcessor();
eventProcessor.processEvents(incomingEvent);

ProcessEvents is required for EventProcessor to work. After event is being consumed by EventProcessor, you can start using its feature.

See below for example: where you are making a call with CreateCall, and wait for CallConnected event of the call.

// send out the invitation, creating call
const callInvite = new CallInvite(target);
const callbackUrl = "https://<MY-EVENT-HANDLER-URL>/events";
const callResult = callAutomationClient.createCall(callInvite, callbackUrl);

// giving 30 seconds timeout for waiting on createCall's event, 'CallConnected'
const createCallEventResult : CreateCallEventResult = await callResult.waitForEventProcessor(undefined, 30000);
// once this returns, call is now established!

// check if it was successful
if (createCallEventResult.isSuccess)
{
  // work with callConnected event
  const callConnectedEvent : CallConnected = createCallEventResult.successResult!;
}

Troubleshooting

Next steps

Contributing

If you'd like to contribute to this library, please read the contributing guide to learn more about how to build and test the code.

@azure/communication-call-automation