JavaScript library for interacting with the Event Gateway.

• Installation
• Usage
• API Reference
  • Constructor
  • List Functions
  • Register Function
  • Delete Function
  • List Subscriptions
  • Subscribe
  • Unsubscribe
  • Emit
  • Invoke

Node:

npm install @serverless/event-gateway-sdk

Browser:

<script type="text/javascript" src="https://unpkg.com/@serverless/event-gateway-sdk@latest/dist/event-gateway-sdk.min.js"></script>

The EventGateway SDK will then be attached to window e.g. and you can access it via window.EventGatewaySDK

When using in your application logic, you'll usually interact with the invoke and emit APIs.

Use the invoke command to synchronously invoke backend function by name. This is similar to an RPC call.

// Construct your client
const SDK = require('@serverless/event-gateway-sdk');
const eventGateway = new SDK({
  url: 'http://myeventgateway.io',
  space: 'prod'
})

// Call your function
eventGateway.invoke({
  functionId: 'users.getUsers',
  data: { 'limit': 100 }
}).then((resp) => resp.json())
  .then((users) => console.log(users))

Use the emit command to emit a named event and payload to your Event Gateway. The event will be received by any function that is subscribed to your event.

// Construct your client
const SDK = require('@serverless/event-gateway-sdk');
const eventGateway = new SDK({
  url: 'http://myeventgateway.io',
  space: 'prod'
})

// Emit your event
eventGateway.emit({
  event: 'user.completedTutorial'
  data: { 'userId': 1234 }
})

Parameters

Object:

• url - string - required, Events API URL
• configurationUrl - string - Configuration API URL. By default, it's the same as url but with 4001 port
• space - string - Space, default: default
• apikey - string - API key for hosted Event Gateway.
• fetchClient - object - fetch client

const SDK = require('@serverless/event-gateway-sdk');
const eventGateway = new SDK({
  url: 'http://localhost',
  space: 'mycompany-prod',
  apikey: '1234abcd'
})

Returns

Promise object resolving to array of function objects

eventGateway.listFunctions()

Parameters

Object:

• functionId - string - function ID
• provider - object - provider spec

For more details see Event Gateway Register Functions docs.

Returns

Promise object resolving to Function object

eventGateway.registerFunction({
  functionId: 'sendEmail',
  provider: {
    type:'awslambda',
    arn: 'xxx',
    region: 'us-west-2',
  }
})

Parameters

Object:

• functionId - string - function ID

eventGateway.deleteFunction({ functionId: 'sendEmail' })

Returns

Promise object resolving to array of subscription objects

eventGateway.listSubscriptions()

Parameters

Object:

• event - string - event type
• functionId - string - function ID
• path - string - optional, subscription path, default: /
• method - string - required for HTTP subscription, HTTP method
• cors - object - optional for HTTP subscriptions, CORS configuration

For more details see Event Gateway Create Subscription docs.

Returns

Promise object resolving to Subscription object

eventGateway.subscribe({
  event: 'user.created',
  functionId: 'sendEmail'
})

Parameters

Object:

• subscriptionId - string - subscription ID

eventGateway.unsubscribe({
  subscriptionId: 'user.created-sendEmail'
})

Parameters

Object:

• event - string - Name of event to emit
• data - object or string - Payload to include with event. If dataType is "application/json", data will be stringified before sending.
• dataType - string - Data type of payload. Default is "application/json"

Returns

fetch response object.

eventGateway.emit({
  event: 'user.completedTutorial'
  data: { 'userId': 1234 }
})

Parameters

Object:

• functionId - string - Name of function to invoke
• data - object or string - Payload to include with invocation. If dataType is "application/json", data will be stringified before sending.
• dataType - string - Data type of payload. Default is "application/json"

Returns

fetch response object.

eventGateway.invoke({
  functionId: 'users.getUsers'
  data: { 'limit': 100 }
}).then((resp) => resp.json())
  .then((users) => console.log(users))

If you are interested to contribute we recommend to check out the Contributing document as it explains how to get started and some of the design decisions for this library.