Apache Kafka Rewind Connector Offsets

arazzo: 1.0.1
info:
  title: Apache Kafka Rewind Connector Offsets
  summary: Stop a connector, capture its offsets, rewind them to a chosen position, and resume.
  description: >-
    Replaying a window of data through a connector means moving its offsets
    backwards, and Kafka Connect will only alter offsets while the connector is
    STOPPED. This workflow enforces that ordering: it stops the connector,
    captures the current offsets so the caller can put them back if the rewind
    is wrong, PATCHes the offsets to the requested position, resumes the
    connector, and confirms it restarted from the new position. Every step
    spells out its request inline so the flow can be read and executed without
    opening the underlying OpenAPI description.
  version: 1.0.0
sourceDescriptions:
- name: kafkaConnectApi
  url: ../openapi/kafka-connect.yml
  type: openapi
workflows:
- workflowId: rewind-connector-offsets
  summary: Alter a stopped connector's offsets to replay data, then resume it.
  description: >-
    Stops the connector, snapshots its offsets for rollback, writes the target
    offsets, and resumes processing from the rewound position.
  inputs:
    type: object
    required:
    - connectorName
    - offsets
    properties:
      connectorName:
        type: string
        description: The name of the connector whose offsets are being rewound.
      offsets:
        type: array
        description: >-
          The target offsets to write. Each entry carries the partition and
          offset objects in the shape the connector's plugin defines, which
          differs between source and sink connectors.
        items:
          type: object
  steps:
  - stepId: stopConnector
    description: >-
      Stop the connector. This is mandatory: Kafka Connect rejects offset
      alterations for connectors that are running or merely paused.
    operationId: stopConnector
    parameters:
    - name: connector
      in: path
      value: $inputs.connectorName
    successCriteria:
    - condition: $statusCode == 204
  - stepId: captureOffsets
    description: >-
      Capture the connector's current offsets before altering them. This
      snapshot is the only rollback path if the rewind target turns out to be
      wrong.
    operationId: getConnectorOffsets
    parameters:
    - name: connector
      in: path
      value: $inputs.connectorName
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      previousOffsets: $response.body#/offsets
  - stepId: rewindOffsets
    description: >-
      Write the target offsets to the stopped connector so that it will replay
      from the requested position when it resumes.
    operationId: alterConnectorOffsets
    parameters:
    - name: connector
      in: path
      value: $inputs.connectorName
    requestBody:
      contentType: application/json
      payload:
        offsets: $inputs.offsets
    successCriteria:
    - condition: $statusCode == 200
  - stepId: verifyOffsets
    description: >-
      Read the offsets back while the connector is still stopped, confirming the
      rewind landed before any data is reprocessed.
    operationId: getConnectorOffsets
    parameters:
    - name: connector
      in: path
      value: $inputs.connectorName
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      rewoundOffsets: $response.body#/offsets
  - stepId: resumeConnector
    description: >-
      Resume the connector so it begins processing from the rewound offsets.
    operationId: resumeConnector
    parameters:
    - name: connector
      in: path
      value: $inputs.connectorName
    successCriteria:
    - condition: $statusCode == 202
  - stepId: confirmReplaying
    description: >-
      Confirm the connector returned to a healthy state and is replaying from
      the new position.
    operationId: getConnectorStatus
    parameters:
    - name: connector
      in: path
      value: $inputs.connectorName
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      connectorState: $response.body#/connector/state
      taskStates: $response.body#/tasks
  outputs:
    previousOffsets: $steps.captureOffsets.outputs.previousOffsets
    rewoundOffsets: $steps.verifyOffsets.outputs.rewoundOffsets
    connectorState: $steps.confirmReplaying.outputs.connectorState