SPL File extract.spl

Specialized toolkits - release 4.3.1.0-prod20190605 > com.ibm.streamsx.iot 1.2.0 > com.ibm.streamsx.iot > extract.spl

Content

Operators

Composites

composite DeviceEventExtractData(output EventsWithData; input stream<DeviceEvent> Events)

Extract application event data into an SPL tuple from the JSON. Extracts the data portion of an device event into the output tuple's attributes.

The application event data is the value of the d key in the event's JSON. It is extracted to tuple type dataType in the output tuple with the assumption is is an JSON object.

The structure of dataType is expected to match JSON schema of the application event data. A subset of the attributes can be specified as well. Only those attributes that are present in dataType and the application event data will be converted. All other attributes will be ignored. If an invalid JSON string is found in the input, the operator will fail. Null values in JSON arrays are ignored. Null values for all other attributes will result in default initializled output attributes. Limitations: BLOB, MAP and COMPLEX attribute types are not supported in dataType and will be ignored.

The event's timestamp (ts in the JSON) is extracted to the attribute eventTs in the output tuple. eventTs has type com.ibm.streamsx.datetime.TimeMillis representing the number of milliseconds since the 1970/01/01 epoch.

Parameters

  • events: Filter expression for events to be extracted
  • dataType: Schema type used to convert the event's data JSON to.

Input Ports

Output Ports

  • EventsWithData: Output stream of device events with the timestamp and data extracted into an SPL tuple. Type of the stream is: DeviceEventTs dataType.