Node client for the Salesforce Pub/Sub API

See the official Pub/Sub API repo for more information on the Salesforce gRPC-based Pub/Sub API.

• Installation and Configuration
  • User supplied authentication
  • Username/password flow
  • OAuth 2.0 client credentials flow (client_credentials)
  • OAuth 2.0 JWT bearer flow
• Basic Example
• Other Examples
  • Publish a platform event
  • Subscribe with a replay ID
  • Subscribe to past events in retention window
  • Handle gRPC stream lifecycle events
  • Use a custom logger

Installation and Configuration

Install the client library with npm install salesforce-pubsub-api-client.

Create a .env file at the root of the project for configuration.

Pick one of these authentication flows and fill the relevant configuration:

• User supplied authentication
• Username/password authentication (recommended for tests)
• OAuth 2.0 client credentials
• OAuth 2.0 JWT Bearer (recommended for production)

Note
The default client logger is fine for a test environement but you'll want to switch to a custom logger with asynchronous logging for increased performance.

User supplied authentication

If you already have a Salesforce client in your app, you can reuse its authentication information. You only need this minimal configuration:

SALESFORCE_AUTH_TYPE=user-supplied
PUB_SUB_ENDPOINT=api.pubsub.salesforce.com:7443

When connecting to the Pub/Sub API, use the following method instead of the standard connect() method to specify authentication information:

awaitclient.connectWithAuth(accessToken,instanceUrl,organizationId,username);

Username/password flow

Warning
Relying on a username/password authentication flow for production is not recommended. Consider switching to JWT auth for extra security.

SALESFORCE_AUTH_TYPE=username-password
SALESFORCE_LOGIN_URL=https://login.salesforce.com
SALESFORCE_USERNAME=YOUR_SALESFORCE_USERNAME
SALESFORCE_PASSWORD=YOUR_SALESFORCE_PASSWORD
SALESFORCE_TOKEN=YOUR_SALESFORCE_USER_SECURITY_TOKEN
PUB_SUB_ENDPOINT=api.pubsub.salesforce.com:7443

OAuth 2.0 client credentials flow (client_credentials)

SALESFORCE_AUTH_TYPE=oauth-client-credentials
SALESFORCE_LOGIN_URL=YOUR_DOMAIN_URL
SALESFORCE_CLIENT_ID=YOUR_CONNECTED_APP_CLIENT_ID
SALESFORCE_CLIENT_SECRET=YOUR_CONNECTED_APP_CLIENT_SECRET
PUB_SUB_ENDPOINT=api.pubsub.salesforce.com:7443

OAuth 2.0 JWT bearer flow

This is the most secure authentication option. Recommended for production use.

SALESFORCE_AUTH_TYPE=oauth-jwt-bearer
SALESFORCE_LOGIN_URL=https://login.salesforce.com
SALESFORCE_CLIENT_ID=YOUR_CONNECTED_APP_CLIENT_ID
SALESFORCE_USERNAME=YOUR_SALESFORCE_USERNAME
SALESFORCE_PRIVATE_KEY_FILE=PATH_TO_YOUR_KEY_FILE
PUB_SUB_ENDPOINT=api.pubsub.salesforce.com:7443

Basic Example

Here's an example that will get you started quickly. It listens to a single account change event.

1. Activate Account change events in Salesforce Setup > Change Data Capture.

2. Create a sample.js file with this content:

   importPubSubApiClientfrom'salesforce-pubsub-api-client';asyncfunctionrun(){try{constclient=newPubSubApiClient();awaitclient.connect();// Subscribe to a single incoming account change eventsconsteventEmitter=awaitclient.subscribe('/data/AccountChangeEvent',1);// Handle incoming eventseventEmitter.on('data',(event)=>{console.log(`Handling ${event.payload.ChangeEventHeader.entityName} change event ${event.replayId}`);console.log(JSON.stringify(event,null,2));});}catch(error){console.error(error);}}run();

3. Run the project with node sample.js

   If everything goes well, you'll see output like this:

   Connected to Salesforce org https://pozil-dev-ed.my.salesforce.com as grpc@pozil.com
   Connected to Pub/Sub API endpoint api.pubsub.salesforce.com:7443
   Topic schema loaded: /data/AccountChangeEvent
   Subscribe request sent for 1 events from /data/AccountChangeEvent...
   

   At this point the script will be on hold and will wait for events.

4. Modify an account record in Salesforce. This fires an account change event.

   Once the client receives an event, it will display it like this:

   Received 1 events, latest replay ID: 17093000
   Handling Account change event 17093000
   {
   "replayId": 17093000,
   "payload": {
   "ChangeEventHeader": {
   "entityName": "Account",
   "recordIds": [
   "0014H00002LbR7QQAV"
   ],
   "changeType": "UPDATE",
   "changeOrigin": "com/salesforce/api/soap/56.0;client=SfdcInternalAPI/",
   "transactionKey": "0005349f-124e-0df1-3a25-f551ab84d237",
   "sequenceNumber": 1,
   "commitTimestamp": 1672428268000,
   "commitNumber": 11449587527037,
   "commitUser": "00558000000yFyDAAU",
   "nulledFields": [],
   "diffFields": [],
   "changedFields": [
   "Rating",
   "LastModifiedDate"
   ]
   },
   "Name": null,
   "Type": null,
   "ParentId": null,
   "BillingAddress": null,
   "ShippingAddress": null,
   "Phone": null,
   "Fax": null,
   "AccountNumber": null,
   "Website": null,
   "Sic": null,
   "Industry": null,
   "AnnualRevenue": null,
   "NumberOfEmployees": null,
   "Ownership": null,
   "TickerSymbol": null,
   "Description": null,
   "Rating": {
   "string": "Hot"
   },
   "Site": null,
   "OwnerId": null,
   "CreatedDate": null,
   "CreatedById": null,
   "LastModifiedDate": {
   "long": 1672428268000
   },
   ...
   }
   }
   

   Note that the change event payloads include all object fields but fields that haven't changed are null. Use the values from ChangeEventHeader.nulledFields, ChangeEventHeader.diffFields and ChangeEventHeader.changedFields to identify actual value changes.

   After receiving the number of requested events, the script will terminate with these messages:

   gRPC stream status: {
   code: 0,
   details: '',
   metadata: Metadata { _internal_repr: {}, flags: 0 }
   }
   gRPC stream ended
   

Other Examples

Publish a platform event

Publish a Sample__e Platform Event with a Message__c field:

constpayload={CreatedDate: newDate().getTime(),// Non-null value required but there's no validity check performed on this fieldCreatedById: 'someone',// Non-null value required but there's no validity check performed on this fieldMessage__c: {string: 'Hello world'}// Field is nullable so we need to specify the 'string' type};constpublishResult=awaitclient.publish('/event/Sample__e',payload);console.log('Published event: ',JSON.stringify(publishResult));

Subscribe with a replay ID

Subscribe to account change events starting from a replay ID:

consteventEmitter=awaitclient.subscribeFromReplayId('/data/AccountChangeEvent',5,17092989);

Subscribe to past events in retention window

Subscribe to past account change events in retention window:

consteventEmitter=awaitclient.subscribeFromEarliestEvent('/data/AccountChangeEvent',3);

Handle gRPC stream lifecycle events

Use the EventEmmitter returned by subscribe methods to handle gRPC stream lifecycle events:

// Stream endeventEmitter.on('end',()=>{console.log('gRPC stream ended');});// Stream erroreventEmitter.on('error',(error)=>{console.error('gRPC stream error: ',JSON.stringify(error));});// Stream status updateeventEmitter.on('status',(status)=>{console.log('gRPC stream status: ',status);});

Use a custom logger

The client logs output to the console by default but you can provide your favorite logger in the client constructor.

When in production, asynchronous logging is preferable for performance reasons.

For example:

importpinofrom'pino';constlogger=pino();constclient=newPubSubApiClient(logger);