ExtractJSON

This formatter extracts a specific value from a JSON payload and writes it back as a new payload or as a metadata field.

Parameters

Field

Defines the JSON key to extract. If the field does not exist an empty string is returned. Field paths can be defined in a format accepted by tgo.MarshalMap.Path. By default this parameter is set to “”.

TrimValues (default: true)

Enables trimming of whitespaces at the beginning and end of the extracted value. By default this parameter is set to true.

Precision

Defines the number of decimal places to use when converting Numbers into strings. If this parameter is set to 0 no restrictions will apply. By default this parameter is set to 0.

Parameters (from core.SimpleFormatter)

ApplyTo

This value chooses the part of the message the formatting should be applied to. Use “” to target the message payload; other values specify the name of a metadata field to target. By default this parameter is set to “”.

SkipIfEmpty

When set to true, this formatter will not be applied to data that is empty or - in case of metadata - not existing. By default this parameter is set to false

Examples

ExampleConsumer:
  Type: consumer.Console
  Streams: console
  Modulators:
    - formatter.ExtractJSON
      Field: host
      ApplyTo: host