Mapper

The Mapper processor allows you to transform input data into a desired output format using a template.
This is useful for reformatting data before sending it to a sink.

Configuration

To configure the Mapper processor, you need to define the outputEvent template in your configuration file. The template uses placeholders to map input data fields to the desired output structure.

It is possible to create nested objects, or to point to a specific field in the input data (also nested). If the field value is an object or an array, it will be copied as is in the output structure.

To configure mapper processor, you need to provide the following parameters in your configuration file:

• type (string): The type of the processor, which should be set to mapper.
• outputEvent (object): The output event template, it's an object which map the input event to the desired output event.

Template

All data inside the {{ }} template will be evaluated. Inside the template it is expected to have the field path to take the value from.

For example, given the following input:

{
  "issue": {
    "key": "ISSUE-123",
    "fields": {
      "summary": "This is a summary",
      "created": "2021-01-01T00:00:00Z"
    }
  }
}

To reach the summary field, the template should be {{ issue.fields.summary }}. To reach the created field, the template should be {{ issue.fields.created }}.

Static data

It is also possible to set static data, for example:

{
  "type": "mapper",
  "outputEvent": {
    "key": "static-value",
    "createdAt": "{{ issue.fields.created }}"
  }
}

In this case, the key field will always have the value static-value.

Limitation

It is not possible combine multiple fields in a single output field.

For example, given the following input:

{
  "name": "value1",
  "surname": "value2"
}

The following configuration is not valid:

{
  "type": "mapper",
  "outputEvent": {
    "fullName": "{{ name }} {{ surname }}"
  }
}

Example

This configuration will map the input data to the outputEvent structure.

{
  "type": "mapper",
  "outputEvent": {
    "key": "{{ issue.key }}",
    "createdAt": "{{ issue.fields.created }}",
    "summary": "{{ issue.fields.summary }}",
    "metadata": {
      "description": "{{ issue.fields.description }}"
    }
  }
}

Given an input event:

{
  "id": "message-id",
  "issue": {
    "key": "ISSUE-123",
    "fields": {
      "summary": "This is a summary",
      "created": "2021-01-01T00:00:00Z",
      "description": "This is a description"
    }
  }
}

It will be transformed into:

{
  "key": "ISSUE-123",
  "summary": "This is a summary",
  "createdAt": "2021-01-01T00:00:00Z",
  "metadata": {
    "description": "This is a description"
  }
}