WebSocket Action

The WebSocket action publishes output messages through a WebSocket connection.

Properties

Property name	Optional	Description
addr	false	The network address of the WebSocket server, such as 127.0.0.1:8080.
path	true	The URL path of the WebSocket server endpoint, such as /api/data.
scheme	true	The URL scheme of the WebSocket server: ws or wss.
insecureSkipVerify	false	Controls whether to skip SSL/TLS certificate verification. Default: false.
certificationPath	true	The client certificate file path for TLS verification.
privateKeyPath	true	The client private key file path for TLS verification.
rootCaPath	true	The root CA certificate file path for TLS verification.
certficationRaw	true	Base64-encoded raw text of the certificate. rekuiper uses certificationPath first if you define both.
privateKeyRaw	true	Base64-encoded raw text of the private key. rekuiper uses privateKeyPath first if you define both.
rootCARaw	true	Base64-encoded raw text of the root CA certificate. rekuiper uses rootCaPath first if you define both.
checkConnection	false	Controls whether rekuiper verifies that a WebSocket connection exists before rule creation. Default: false.

Other common sink properties are supported. Refer to sink common properties for more information.

rekuiper as WebSocket Client

When the WebSocket sink defines both addr and path, rekuiper operates as a WebSocket client. rekuiper connects to the remote server and pushes messages through that connection.

You can verify the connectivity of the sink endpoint before rule execution by using the REST API: Connectivity Check.

rekuiper as WebSocket Server

When the WebSocket sink defines path and leaves addr empty, rekuiper operates as a WebSocket server. rekuiper waits for remote clients to connect and pushes messages to connected clients.

When checkConnection is set to true, rekuiper verifies that the corresponding WebSocket endpoint and active connection exist before creating the rule. Refer to Manage WebSocket Connection for details on managing connections through the REST API.

Server Configuration

To configure rekuiper as a WebSocket server endpoint, configure the settings in etc/sources/websocket.yaml:

source:
  ## Configurations for the global websocket server for websocket source
  # HTTP data service ip
  httpServerIp: 0.0.0.0
  # HTTP data service port
  httpServerPort: 10081
  # httpServerTls:
  #    certfile: /var/https-server.crt
  #    keyfile: /var/https-server.key

Configure the following properties:

• httpServerIp: The IP address to bind the HTTP data server.
• httpServerPort: The TCP port to bind the HTTP data server.
• httpServerTls: The TLS configuration for the HTTP server.

The global server starts when any rule that requires a WebSocket endpoint is started. It stops when all associated rules are stopped.

Sample Usage

The following configuration publishes output data to an external WebSocket server:

{
  "websocket": {
    "addr": "127.0.0.1:8080",
    "path": "/api/data"
  }
}