jsFilter component: script filter. You can use JavaScript script to filter msg, metadata, msgType. The script should return the route to True or False chain.

JavaScript script supports ECMAScript 5.1(+) syntax specification and some ES6 specifications, such as: async/await/Promise/let. It allows calling Go custom functions in the script, please refer to udf .

Configuration

Field	Type	Description	Default value
jsScript	string	js script	None

• jsScript: You can filter msg, metadata, msgType. This field is the following function body content

      function Filter(msg, metadata, msgType) { 
          ${jsScript} 
       }
  

  • msg: Message content, if dataType=JSON, type is: jsonObject, you can use msg.temperature to operate. If dataType is other types, the field type is:string
  • metadata: Message metadata, type: jsonObject
  • msgType: Message type
  • Function return value type: boolean, determines the connection relationship with the next node (Relation Type)

Note

jsScript script must have a return value, return true/false;
Script execution timeout configuration reference: config.ScriptMaxExecutionTime

Relation Type

• True: Send the message to the True chain
• False: Send the message to the False chain
• Failure: Execution failed, send the message to the Failure chain

Execution result

This component will not change the content of msg, metadata and msgType.

Configuration example

  {
    "id": "s1",
    "type": "jsFilter",
    "name": "Filter",
    "configuration": {
      "jsScript": "return msg.temperature > 50;"
    }
  }

Application example

If msgType is: EVENT_APP1, then push the message to: http://192.168.136.26:9099/app1/api/msg, otherwise push to: http://192.168.136.26:9099/app2/api/msg

{
  "ruleChain": {
    "id":"rule01",
    "name": "Test rule chain",
    "root": true
  },
  "metadata": {
    "nodes": [
      {
        "id": "s1",
        "type": "jsFilter",
        "name": "Filter",
        "configuration": {
          "jsScript": "return msgType =='EVENT_APP1';"
        }
      },
      {
        "id": "s2",
        "type": "restApiCall",
        "name": "Push data-app2",
        "configuration": {
          "restEndpointUrlPattern": "http://192.168.136.26:9099/app1/api/msg",
          "requestMethod": "POST",
          "maxParallelRequestsCount": 200
        }
      },
      {
        "id": "s3",
        "type": "restApiCall",
        "name": "Push data-app2",
        "configuration": {
          "restEndpointUrlPattern": "http://192.168.136.26:9099/app2/api/msg",
          "requestMethod": "POST",
          "maxParallelRequestsCount": 200
        }
      }
    ],
    "connections": [
      {
        "fromId": "s1",
        "toId": "s2",
        "type": "True"
      },
      {
        "fromId": "s1",
        "toId": "s3",
        "type": "False"
      }
    ]
  }
}