api.md

API

The Event Gateway has two APIs: the Configuration API for registering functions and subscriptions, and the runtime Events API for sending events into the Event Gateway. This document contains the API documentation for both Events and Configuration APIs. You can also find links to OpenAPI specs for these APIs.

Contents

1. Events API
   1. Event Definition
   2. How To Emit an Event
   3. HTTP Request Event
   4. CORS
   5. Legacy Mode
2. Configuration API
   1. Event Types
      1. Create Event Type
      2. Update Event Type
      3. Delete Event Type
      4. List Event Types
      5. Get Event Type
   2. Functions
      1. Register Function
      2. Update Function
      3. Delete Function
      4. List Functions
      5. Get Function
   3. Subscriptions
      1. Create Subscription
      2. Update Subscription
      3. Delete Subscription
      4. List Subscriptions
      5. Get Subscription
   4. CORS
      1. Create CORS Configuration
      2. Update CORS Configuration
      3. Delete CORS Configuration
      4. List CORS Configurations
      5. Get CORS Configuration
   5. Prometheus Metrics
   6. Status

Events API

The Event Gateway exposes an API for emitting events. By default Events API runs on :4000 port.

Event Definition

All data that passes through the Event Gateway is formatted as a CloudEvent, based on CloudEvents v0.1 schema.

Example:

{
  "eventType": "myapp.user.created",
  "eventID": "66dfc31d-6844-42fd-b1a7-a489a49f65f3",
  "cloudEventsVersion": "0.1",
  "source": "https://serverless.com/event-gateway/#transformationVersion=0.1",
  "eventTime": "1990-12-31T23:59:60Z",
  "data": { "foo": "bar" },
  "contentType": "application/json"
}

How To Emit an Event

Creating a subscription requires path (default: /), method (default: POST) and eventType. path indicates path under which you can send the event.

Endpoint

POST <Events API URL>/<Subscription Path>

Request

CloudEvents payload

Response

Status code:

• 202 Accepted - this status code is returned if there is no sync subscription defined. Otherwise, status code is controlled by function synchronously subscribed on this endpoint.

HTTP Request Event

Not all data are events that's why Event Gateway has a special, built-in http.request event type that enables subscribing to raw HTTP requests. It's especially helpful for building REST APIs or supporting legacy payloads. http.request event is a CloudEvent created by Event Gateway where data field has the following structure:

• path - string - request path
• method - string - request method
• headers - object - request headers
• host - string - request host
• query - object - query parameters
• params - object - matched path parameters
• body - depends on Content-Type header - request payload

CORS

By default cross-origin resource sharing (CORS) is disabled. CORS is configured per-method/path basis using CORS Configuration API.

Event Gateway handles preflight OPTIONS requests for you. You don't need to setup subscription for OPTIONS method because the Event Gateway will respond with all appropriate headers.

Legacy Mode

Legacy mode is deprecated and will be removed in upcoming releases.

In legacy mode, Event Gateway is able to recognize event type based on Event header. If the event is not formatted according to CloudEvents specification Event Gateway looks for this header and creates CloudEvent internally. In this case, whole request body is put into data field.

Event Data Type

The MIME type of the data block can be specified using the Content-Type header (by default it's application/octet-stream). This allows the Event Gateway to understand how to deserialize the data block if it needs to. In case of application/json type the Event Gateway passes JSON payload to the target functions. In any other case the data block is base64 encoded.

Configuration API

OpenAPI spec

The Event Gateway exposes a RESTful JSON configuration API. By default Configuration API runs on :4001 port.

Event Types

Create Event Type

Endpoint

POST <Configuration API URL>/v1/spaces/<space>/eventtypes

Request

JSON object:

• name - string - required, event type name
• authorizerId - string - authorizer function ID
• metadata - object - arbitrary metadata

Response

Status code:

• 201 Created on success
• 400 Bad Request on validation error
• 409 Conflict if event type already exists

JSON object:

• space - string - space name
• name - string - event type name
• authorizerId - string - authorizer function ID
• metadata - object - arbitrary metadata

---

Update Event Type

Endpoint

PUT <Configuration API URL>/v1/spaces/<space>/eventtypes/<event type name>

Request

JSON object:

• authorizerId - string - authorizer function ID
• metadata - object - arbitrary metadata

Response

Status code:

• 200 OK on success
• 400 Bad Request on validation error or if the authorizer function doesn't exist
• 404 Not Found if event type doesn't exist

JSON object:

• space - string - space name
• name - string - event type name
• authorizerId - string - authorizer function ID
• metadata - object - arbitrary metadata

---

Delete Event Type

Delete event type. This operation fails if there is at least one subscription using the event type.

Endpoint

DELETE <Configuration API URL>/v1/spaces/<space>/eventtypes/<event type name>

Response

Status code:

• 204 No Content on success
• 400 Bad Request if there are subscriptions using the event type
• 404 Not Found if event type doesn't exist

---

List Event Types

Endpoint

GET <Configuration API URL>/v1/spaces/<space>/eventtypes

Query Parameters

Endpoint allows filtering list of returned object with filters passed as query parameters. Currently, filters can only use metadata properties e.g. metadata.service=usersService.

Response

Status code:

• 200 OK on success

JSON object:

• eventTypes - array of object - event types:
  • space - string - space name
  • name - string - event type name
  • authorizerId - string - authorizer function ID
  • metadata - object - arbitrary metadata

---

Get Event Type

Endpoint

GET <Configuration API URL>/v1/spaces/<space>/eventtypes/<event type name>

Response

Status code:

• 200 OK on success
• 404 Not Found if event type doesn't exist

JSON object:

• space - string - space name
• name - string - event type name
• authorizerId - string - authorizer function ID
• metadata - object - arbitrary metadata

Functions

Register Function

Endpoint

POST <Configuration API URL>/v1/spaces/<space>/functions

Request

JSON object:

• functionId - string - required, function ID
• type - string - required, provider type: awslambda or http
• provider - object - required, provider specific information about a function, depends on type:
  • for AWS Lambda:
    • arn - string - required, AWS ARN identifier
    • region - string - required, region name
    • awsAccessKeyId - string - optional, AWS API key ID. By default credentials from the environment are used.
    • awsSecretAccessKey - string - optional, AWS API access key. By default credentials from the environment are used.
    • awsSessionToken - string - optional, AWS session token
  • for HTTP function:
    • url - string - required, the URL of an http or https remote endpoint
  • for AWS Kinesis connector:
    • streamName - string - required, AWS Kinesis Stream Name
    • region - string - required, region name
    • awsAccessKeyId - string - optional, AWS API key ID. By default credentials from the environment are used.
    • awsSecretAccessKey - string - optional, AWS API access key. By default credentials from the environment are used.
    • awsSessionToken - string - optional, AWS session token
  • for AWS Firehose connector:
    • deliveryStreamName - string - required, AWS Firehose Delivery Stream Name
    • region - string - required, region name
    • awsAccessKeyId - string - optional, AWS API key ID. By default credentials from the environment are used.
    • awsSecretAccessKey - string - optional, AWS API access key. By default credentials from the environment are used.
    • awsSessionToken - string - optional, AWS session token
  • for AWS SQS connector:
    • queueUrl - string - required, AWS SQS Queue URL
    • region - string - required, region name
    • awsAccessKeyId - string - optional, AWS API key ID. By default credentials from the environment are used.
    • awsSecretAccessKey - string - optional, AWS API access key. By default credentials from the environment are used.
    • awsSessionToken - string - optional, AWS session token
• metadata - object - arbitrary metadata

Response

Status code:

• 201 Created on success
• 400 Bad Request on validation error
• 409 Conflict if function already exists

JSON object:

• space - string - space name
• functionId - string - function ID
• provider - object - provider specific information about a function
• metadata - object - arbitrary metadata

---

Update Function

Endpoint

PUT <Configuration API URL>/v1/spaces/<space>/functions/<function ID>

Request

JSON object:

• type - string - required, provider type: awslambda or http
• provider - object - required, provider specific information about a function, depends on type:
  • for AWS Lambda:
    • arn - string - required, AWS ARN identifier
    • region - string - required, region name
    • awsAccessKeyId - string - optional, AWS API key ID
    • awsSecretAccessKey - string - optional, AWS API key
    • awsSessionToken - string - optional, AWS session token
  • for HTTP function:
    • url - string - required, the URL of an http or https remote endpoint
• metadata - object - arbitrary metadata

Response

Status code:

• 200 OK on success
• 400 Bad Request on validation error
• 404 Not Found if function doesn't exist

JSON object:

• space - string - space name
• functionId - string - function ID
• provider - object - provider specific information about a function
• metadata - object - arbitrary metadata

---

Delete Function

Delete all types of functions. This operation fails if the function is currently in-use by a subscription.

Endpoint

DELETE <Configuration API URL>/v1/spaces/<space>/functions/<function ID>

Response

Status code:

• 204 No Content on success
• 404 Not Found if function doesn't exist

---

List Functions

Endpoint

GET <Configuration API URL>/v1/spaces/<space>/functions

Query Parameters

Endpoint allows filtering list of returned object with filters passed as query parameters. Currently, filters can only use metadata properties e.g. metadata.service=usersService.

Response

Status code:

• 200 OK on success

JSON object:

• functions - array of object - functions:
  • space - string - space name
  • functionId - string - function ID
  • provider - object - provider specific information about a function
  • metadata - object - arbitrary metadata

---

Get Function

Endpoint

GET <Configuration API URL>/v1/spaces/<space>/functions/<function ID>

Response

Status code:

• 200 OK on success
• 404 Not Found if function doesn't exist

JSON object:

• space - string - space name
• functionId - string - function ID
• provider - object - provider specific information about a function
• metadata - object - arbitrary metadata

Subscriptions

Create Subscription

Endpoint

POST <Configuration API URL>/v1/spaces/<space>/subscriptions

Request

• type - string - subscription type, sync or async
• eventType - string - event type
• functionId - string - ID of function to receive events
• path - string - optional, URL path under which events (HTTP requests) are accepted, default: /
• method - string - optional, HTTP method that accepts requests, default: POST
• metadata - object - arbitrary metadata

Response

Status code:

• 201 Created on success
• 400 Bad Request on validation error
• 409 Conflict if subscription already exists

JSON object:

• space - string - space name
• subscriptionId - string - subscription ID
• type - string - subscription type
• eventType - string - event type
• functionId - function ID
• method - string - HTTP method that accepts requests
• path - string - path that accepts requests, starts with /
• metadata - object - arbitrary metadata

---

Update Subscription

Endpoint

PUT <Configuration API URL>/v1/spaces/<space>/subscriptions/<subscription ID>

Request

Note that type, eventType, functionId, path, and method may not be updated in an UpdateSubscription call.

• type - string - subscription type, sync or async
• eventType - string - event type
• functionId - string - ID of function to receive events
• path - string - optional, URL path under which events (HTTP requests) are accepted, default: /
• method - string - optional, HTTP method that accepts requests, default: POST
• metadata - object - arbitrary metadata

Response

Status code:

• 200 Created on success
• 400 Bad Request on validation error
• 404 Not Found if subscription doesn't exist

JSON object:

• space - string - space name
• subscriptionId - string - subscription ID
• type - string - subscription type
• eventType - string - event type
• functionId - function ID
• method - string - HTTP method that accepts requests
• path - string - path that accepts requests, starts with /
• metadata - object - arbitrary metadata

---

Delete Subscription

Endpoint

DELETE <Configuration API URL>/v1/spaces/<space>/subscriptions/<subscription ID>

Response

Status code:

• 204 No Content on success
• 404 Not Found if subscription doesn't exist

---

List Subscriptions

Endpoint

GET <Configuration API URL>/v1/spaces/<space>/subscriptions

Query Parameters

Endpoint allows filtering list of returned object with filters passed as query parameters. Currently, filters can only use metadata properties e.g. metadata.service=usersService.

Response

Status code:

• 200 OK on success

JSON object:

• subscriptions - array of object - subscriptions
  • space - string - space name
  • subscriptionId - string - subscription ID
  • type - string - subscription type
  • eventType - string - event type
  • functionId - function ID
  • method - string - HTTP method that accepts requests
  • path - string - path that accepts requests, starts with /
  • metadata - object - arbitrary metadata

---

Get Subscription

Endpoint

GET <Configuration API URL>/v1/spaces/<space>/subscriptions/<subscription ID>

Response

Status code:

• 200 OK on success
• 404 NotFound if subscription doesn't exist

JSON object:

• space - string - space name
• subscriptionId - string - subscription ID
• type - string - subscription type
• eventType - string - event type
• functionId - function ID
• method - string - HTTP method that accepts requests
• path - string - path that accepts requests, starts with /
• metadata - object - arbitrary metadata

CORS

Create CORS Configuration

Endpoint

POST <Configuration API URL>/v1/spaces/<space>/cors

Request

• method - string - endpoint method
• path - string - endpoint path
• allowedOrigins - array of string - list of allowed origins. An origin may contain a wildcard (*) to replace 0 or more characters (i.e.: http://*.domain.com), default: *
• allowedMethods - array of string - list of allowed methods, default: HEAD, GET, POST
• allowedHeaders - array of string - list of allowed headers, default: Origin, Accept, Content-Type
• allowCredentials - bool - allow credentials, default: false
• metadata - object - arbitrary metadata

Response

Status code:

• 201 Created on success
• 400 Bad Request on validation error
• 409 Conflict if CORS configuration already exists

JSON object:

• space - string - space name
• corsId - string - CORS configuration ID
• method - string - endpoint method
• path - string - endpoint path
• allowedOrigins - array of string - list of allowed origins
• allowedMethods - array of string - list of allowed methods
• allowedHeaders - array of string - list of allowed headers
• allowCredentials - boolean - allow credentials
• metadata - object - arbitrary metadata

---

Update CORS Configuration

Endpoint

PUT <Configuration API URL>/v1/spaces/<space>/cors/<CORS ID>

Request

Note that method, and path may not be updated in an UpdateCORS call.

• method - string - endpoint method
• path - string - endpoint path
• allowedOrigins - array of string - list of allowed origins
• allowedMethods - array of string - list of allowed methods
• allowedHeaders - array of string - list of allowed headers
• allowCredentials - boolean - allow credentials
• metadata - object - arbitrary metadata

Response

Status code:

• 200 Created on success
• 400 Bad Request on validation error
• 404 Not Found if CORS configuration doesn't exist

JSON object:

• space - string - space name
• corsId - string - CORS configuration ID
• method - string - endpoint method
• path - string - endpoint path
• allowedOrigins - array of string - allowed origins
• allowedMethods - array of string - allowed methods
• allowedHeaders - array of string - allowed headers
• allowCredentials - boolean - allow credentials
• metadata - object - arbitrary metadata

---

Delete CORS Configuration

Endpoint

DELETE <Configuration API URL>/v1/spaces/<space>/cors/<CORS ID>

Response

Status code:

• 204 No Content on success
• 404 Not Found if CORS configuration doesn't exist

---

List CORS Configurations

Endpoint

GET <Configuration API URL>/v1/spaces/<space>/cors

Query Parameters

Endpoint allows filtering list of returned object with filters passed as query parameters. Currently, filters can only use metadata properties e.g. metadata.service=usersService.

Response

Status code:

• 200 OK on success

JSON object:

• cors - array of object - CORS configurations
  • space - string - space name
  • corsId - string - CORS configuration ID
  • method - string - endpoint method
  • path - string - endpoint path
  • allowedOrigins - array of string - allowed origins
  • allowedMethods - array of string - allowed methods
  • allowedHeaders - array of string - allowed headers
  • allowCredentials - boolean - allow credentials
  • metadata - object - arbitrary metadata

---

Get CORS Configuration

Endpoint

GET <Configuration API URL>/v1/spaces/<space>/cors/<CORS ID>

Response

Status code:

• 200 OK on success
• 404 NotFound if CORS configuration doesn't exist

JSON object:

• space - string - space name
• corsId - string - CORS configuration ID
• method - string - endpoint method
• path - string - endpoint path
• allowedOrigins - array of string - allowed origins
• allowedMethods - array of string - allowed methods
• allowedHeaders - array of string - allowed headers
• allowCredentials - boolean - allow credentials
• metadata - object - arbitrary metadata

Prometheus Metrics

Endpoint exposing Prometheus metrics.

Endpoint

GET <Configuration API URL>/metrics

Status

Dummy endpoint (always returning 200 OK status code) for checking if the event gateway instance is running.

Endpoint

GET <Configuration API URL>/v1/status