Participant Intermediary

The CLAMP Participant Intermediary is a common library in ONAP, which does common message and state handling for participant implementations. It provides a Java API, which participant implementations implement to receive and send messages to the CLAMP runtime and to handle Automation Composition Element state.

Terminology

  • Broadcast message: a message for all participants (participantId=null)

  • Message to a participant: a message only for a participant (participantId properly filled)

  • MessageSender: a class that takes care of sending messages from participant-intermediary

  • GUI: graphical user interface, Postman or a Front-End Application

  • Message Broker: It supports the message Broker Kafka

Inbound messages to participants

  • PARTICIPANT_REGISTER_ACK: received as a response from clamp-acm runtime server as an acknowledgement to ParticipantRegister message sent from a participant

  • PARTICIPANT_DEREGISTER_ACK: received as a response from clamp-acm runtime server as an acknowledgement to ParticipantDeregister message sent from a participant

  • AUTOMATION_COMPOSITION_STATE_CHANGE: a message received from clamp-acm runtime server for a state change of clamp-acm

  • AUTOMATION_COMPOSITION_DEPLOY: a message received from clamp-acm runtime server for a clamp-acm deploy with clamp-acm instances

  • AUTOMATION_COMPOSITION_PREPARE: a message received from clamp-acm runtime server for a clamp-acm prepare/review with clamp-acm instances

  • PARTICIPANT_PRIME: a message received from clamp-acm runtime server for a participant update with tosca definitions of clamp-acm

  • PARTICIPANT_STATUS_REQ: A status request received from clamp-acm runtime server to send an immediate ParticipantStatus from all participants

  • PROPERTIES_UPDATE: a message received from clamp-acm runtime server for updating the Ac instance property values

  • AUTOMATION_COMPOSITION_MIGRATION: a message received from clamp-acm runtime server for migrating/migration-precheck the Ac instance from a composition definition to a composition definition target

  • PARTICIPANT_SYNC_MSG: a message received from clamp-acm runtime server with tosca definitions and the Ac instances to handle synchronization

Outbound messages

  • PARTICIPANT_REGISTER: is sent by a participant during startup

  • PARTICIPANT_DEREGISTER: is sent by a participant during shutdown

  • PARTICIPANT_STATUS: is sent by a participant as heartbeat with the status and health of a participant

  • AUTOMATIONCOMPOSITION_STATECHANGE_ACK: is an acknowledgement sent by a participant as a response to AutomationCompositionStateChange

  • AUTOMATION_COMPOSITION_DEPLOY_ACK: is an acknowledgement sent by a participant as a response to AutomationCompositionDeploy

  • PARTICIPANT_PRIME_ACK: is an acknowledgement sent by a participant as a response to ParticipantPrime

Design of a PARTICIPANT_REGISTER message

  • A participant starts and send a PARTICIPANT_REGISTER message with participantId, replicaId and Supported Element Definition Types

  • in ACM-runtime ParticipantRegisterListener collects the message from Message Broker

  • if participant is not present in DB, it saves participant reference with status ON_LINE to DB

  • It triggers the execution to send a PARTICIPANT_REGISTER_ACK message to the participant registered

  • if participant is present in DB and there are AC Definitions related to the Participant, it triggers the execution to send a PARTICIPANT_SYNC_MSG message to synchronize participant

Design of a PARTICIPANT_DEREGISTER message

  • A participant is going to close and undeploys all AC-elements and send a PARTICIPANT_DEREGISTER message

  • in ACM-runtime, ParticipantDeregisterListener collects the message from Message Broker

  • It saves participant reference with status OFF_LINE to DB

  • It triggers the execution to send a PARTICIPANT_DEREGISTER_ACK message to the participant deregistered

  • Participant is not monitored.

Prime of an Automation Composition Definition Type

  • ACM-runtime assigns the AC Definition to the participants based of Supported Element Definition Type by participant

  • it triggers the execution to send a broadcast PARTICIPANT_PRIME message

  • the message is built by ParticipantPrimePublisher using Tosca Service Template data (to fill the list of ParticipantDefinition)

  • Participant-intermediary will receive a PARTICIPANT_PRIME message and stores the Tosca Service Template data on CacheProvider

  • Each participant performs its designated job of prime

DePrime of an Automation Composition Definition Type

  • ACM-runtime triggers the execution to send a broadcast PARTICIPANT_PRIME message

  • the message is built by ParticipantPrimePublisher with an empty list of ParticipantDefinition

  • Participant-intermediary will receive a PARTICIPANT_PRIME message and deletes the Tosca Service Template data on CacheProvider

  • Each participant performs its designated job of deprime

Design of “issues automation composition commands to automation compositions” - case PREPARE

  • AUTOMATION_COMPOSITION_PREPARE message with instantiation details and PREPARE order state is sent to participants

  • Participant-intermediary will receive AUTOMATION_COMPOSITION_PREPARE message and sends the details of AutomationCompositionElements to participants

  • Each participant performs its designated job of prepare

Design of “issues automation composition commands to automation compositions” - case UNDEPLOYED to DEPLOYED

  • AUTOMATION_COMPOSITION_DEPLOY message with instantiation details and DEPLOY order state is sent to participants

  • Participant-intermediary validates the current deployState change

  • Participant-intermediary will receive AUTOMATION_COMPOSITION_DEPLOY message and sends the details of AutomationCompositionElements to participants

  • Each participant performs its designated job of deployment by interacting with respective frameworks

Design of “issues automation composition commands to automation compositions” - case REVIEW

  • AUTOMATION_COMPOSITION_PREPARE message with instantiation details and REVIEW order state is sent to participants

  • Participant-intermediary will receive AUTOMATION_COMPOSITION_PREPARE message and sends the details of AutomationCompositionElements to participants

  • Each participant performs its designated job of review

Design of “issues automation composition commands to automation compositions” - case DEPLOYED to UNDEPLOYED

  • AUTOMATION_COMPOSITION_STATE_CHANGE message with instantiation details and UNDEPLOY order state is sent to participants

  • Participant-intermediary validates the current deployState change

  • Participant-intermediary will receive AUTOMATION_COMPOSITION_STATE_CHANGE message and sends AC-element details to participants

  • Each participant performs its designated job of undeployment by interacting with respective frameworks

Update of an Automation Composition Instance

  • ACM-runtime updates the instance properties of the deployed Ac instances

  • it triggers the execution to send a broadcast PROPERTIES_UPDATE message

  • the message is built by AcElementPropertiesPublisher using the REST request payload (to fill the list of elements with the updated property values)

  • Participant-intermediary will receive a PROPERTIES_UPDATE message and stores the updated values of the elements on CacheProvider

  • Each participant performs its designated job of update by interacting with respective frameworks

Migrate-precheck of an Automation Composition Instance

  • it triggers the execution to send a broadcast AUTOMATION_COMPOSITION_MIGRATION message with precheck set to true

  • the message is built by AutomationCompositionMigrationPublisher using the REST request payload (to fill the compositionTargetId and list of elements with the updated property values)

  • Participant-intermediary will receive a AUTOMATION_COMPOSITION_MIGRATION message and use a copy of the instance from CacheProvider to merge with data from the message

  • Each participant performs its designated job of migrate-precheck

Migrate of an Automation Composition Instance

  • ACM-runtime saves the compositionTargetId and updates the instance properties of the deployed Ac instances

  • it triggers the execution to send a broadcast AUTOMATION_COMPOSITION_MIGRATION message with precheck set to false

  • the message is built by AutomationCompositionMigrationPublisher using the REST request payload (to fill the compositionTargetId and list of elements with the updated property values)

  • Participant-intermediary will receive a AUTOMATION_COMPOSITION_MIGRATION message and stores the compositionTargetId and the updated values of the elements on CacheProvider

  • Each participant performs its designated job of migrate by interacting with respective frameworks

Design of “issues automation composition commands to automation compositions” - case LOCKED to UNLOCKED

  • AUTOMATION_COMPOSITION_STATE_CHANGE message with instantiation details and UNLOCK order state is sent to participants

  • Participant-intermediary validates the current lockState change

  • Participant-intermediary will receive AUTOMATION_COMPOSITION_STATE_CHANGE message

  • Each participant performs its designated job of unlock

Design of “issues automation composition commands to automation compositions” - case UNLOCKED to LOCKED

  • AUTOMATION_COMPOSITION_STATE_CHANGE message with instantiation details and LOCK order state is sent to participants

  • Participant-intermediary validates the current lockState change

  • Participant-intermediary will receive AUTOMATION_COMPOSITION_STATE_CHANGE message

  • Each participant performs its designated job of lock

Design of Delete - case UNDEPLOYED to DELETED

  • AUTOMATION_COMPOSITION_STATE_CHANGE message with instantiation details and DELETE order state is sent to participants

  • Participant-intermediary validates the current deployState change

  • Participant-intermediary will receive AUTOMATION_COMPOSITION_STATE_CHANGE message and sends AC-element details to participants

  • Each participant performs its designated job of removing instantiation data if not done in undeployment

  • Participant-intermediary will remove instantiation data

Design of a PARTICIPANT_STATUS_REQ message

  • ACM-runtime triggers the execution to send a broadcast PARTICIPANT_STATUS_REQ message or to send it to a specific participant

  • the message is built by ParticipantStatusReqPublisher

  • Participant-intermediary will receive a PARTICIPANT_STATUS_REQ message

Design of a PARTICIPANT_STATUS message

  • A participant sends a scheduled PARTICIPANT_STATUS message or in response to a PARTICIPANT_STATUS_REQ message

  • This message will hold the state and healthStatus of all the participants running actively

  • PARTICIPANT_STATUS message holds a special attribute to return Tosca definitions, this attribute is populated only in response to PARTICIPANT_STATUS_REQ

Design of a AUTOMATION_COMPOSITION_DEPLOY_ACK message

  • A participant sends AUTOMATION_COMPOSITION_DEPLOY_ACK message in response to a AUTOMATION_COMPOSITION_DEPLOY message.

  • For each AC-elements moved to the ordered state as indicated by the AUTOMATION_COMPOSITION_DEPLOY

  • AutomationCompositionUpdateAckListener in ACM-runtime collects the messages from Message Broker

  • It checks the deployStatus of all automation composition elements

  • It updates the AC-instance in DB accordingly

Design of a AUTOMATIONCOMPOSITION_STATECHANGE_ACK message

  • A participant sends AUTOMATIONCOMPOSITION_STATECHANGE_ACK message in response to a AUTOMATIONCOMPOSITION_STATECHANGE message.

  • For each AC-elements moved to the ordered state as indicated by the AUTOMATIONCOMPOSITION_STATECHANGE

  • AutomationCompositionStateChangeAckListener in ACM-runtime collects the messages from Message Broker

  • It checks the deployStatus/lockStatus of all automation composition elements

  • It updates the AC-instance in DB accordingly