Investigation on using Async-api

Investigation on using Async-api for clamp messaging doc.

Tool:

  • Java AsyncAPI: This tool stores modules, which simplifies interacting with AsyncAPI in jvm ecosystem.

  • SCS MultiApi Plugin: This is a plugin designed to help developers automatizing the creation of code classes from YML files based on AsyncApi and OpenAPI. It…

  • ZenWave SDK: DDD and API-First for Event-Driven Microservices

  • Springwolf: Automated documentation for event-driven applications built with Spring Boot

SCS MultiApi Plugin

This is a plugin designed to help developers automatizing the creation of code classes from YML files based on AsyncApi and OpenAPI. It is presented in 2 flavours Maven and Gradle (MPL-2.0 license).

This plugin allows developers to automatize the creation of code classes for REST and Kafka connections, based on YML files under the AsyncApi and OpenApi specifications. In the latter case, many of the configuration options and classes that are generated are based on reimplementation or modification of the OpenAPI Generator models and template designs.

The generation of the REST and Kafka connections is independent each other and could be used only one, or both at the same time.

Link: (https://github.com/sngular/scs-multiapi-plugin)

Below the plugin for policy-clamp-models:

pom
<plugin> <groupId>com.sngular</groupId> <artifactId>scs-multiapi-maven-plugin</artifactId> <version>5.3.5</version> <executions> <execution> <id>asyncapi</id> <phase>generate-sources</phase> <goals> <goal>asyncapi-generation</goal> </goals> <configuration> <specFiles> <specFile> <filePath>${project.basedir}/src/main/resources/asyncapi/asyncapi.yaml</filePath> <supplier> <ids>sendMessage</ids> <modelPackage>org.onap.policy.clamp.models.acm.messages.kafka.participant</modelPackage> </supplier> <consumer> <ids>receiveMessage</ids> <modelPackage>org.onap.policy.clamp.models.acm.messages.kafka.participant</modelPackage> </consumer> </specFile> </specFiles> <generatedSourcesFolder>sources-generated</generatedSourcesFolder> </configuration> </execution> </executions> </plugin>



Below the models/src/main/resources/asyncapi/asyncapi.yaml for ParticipantRegister and ParticipantRegisterAck messages.

asyncapi.yaml
asyncapi: 2.0.0 info: title: Account Service version: '1.0.0' description: Manages user accounts in the system. servers: production: url: kafka:9092 protocol: kafka description: kafka broker channels: policy-acm-participant: publish: operationId: sendMessage message: $ref: '#/components/messages/ParticipantRegisterAck' policy-acm-acruntime: subscribe: operationId: receiveMessage message: $ref: '#/components/messages/ParticipantRegister' components: messages: ParticipantRegister: name: ParticipantRegister title: ParticipantRegister summary: Register a participant contentType: application/json payload: $ref: '#/components/schemas/ParticipantRegister' ParticipantRegisterAck: name: ParticipantRegisterAck title: ParticipantRegisterAck summary: Send message back from a registered participant contentType: application/json payload: $ref: '#/components/schemas/ParticipantRegisterAck' schemas: ParticipantRegister: type: object properties: messageType: description: "Message Type" $ref: '#/components/schemas/ParticipantMessageType' default: 'PARTICIPANT_REGISTER' messageId: type: string format: uuid timestamp: type: string format: dateTime participantId: type: string format: uuid participantSupportedElementType: type: array items: $ref: '#/components/schemas/ParticipantSupportedElementType' ParticipantSupportedElementType: type: object properties: id: type: string format: uuid typeName: type: string typeVersion: type: string ParticipantRegisterAck: type: object properties: messageType: description: "Message Type" $ref: '#/components/schemas/ParticipantMessageType' default: 'PARTICIPANT_REGISTER_ACK' responseTo: type: string format: uuid timestamp: type: string format: dateTime participantId: type: string format: uuid Message: type: string ParticipantMessageType: type: string enum: - PARTICIPANT_STATUS - PARTICIPANT_STATE_CHANGE - AUTOMATION_COMPOSITION_DEPLOY - AUTOMATION_COMPOSITION_STATE_CHANGE - PARTICIPANT_REGISTER - PARTICIPANT_REGISTER_ACK - PARTICIPANT_DEREGISTER - PARTICIPANT_DEREGISTER_ACK - PARTICIPANT_PRIME - PARTICIPANT_PRIME_ACK - AUTOMATION_COMPOSITION_DEPLOY_ACK - AUTOMATION_COMPOSITION_STATECHANGE_ACK - PARTICIPANT_STATUS_REQ - PROPERTIES_UPDATE - PARTICIPANT_RESTART - AUTOMATION_COMPOSITION_MIGRATION



  • the plugin generates model classes with builder support; is mandatory create the bean with the builder;

  • there is no support for java.util.UUID and java.time.Instant;

  • appliesTo method have to be refactored;

ZenWave SDK

ZenWave SDK is a configurable and extensible toolkit for Domain Driven Design (DDD) and API-First that can generate code from a mix of different models including (MIT license):

  • ZDL Domain Language

  • AsyncAPI

  • OpenAPI

Link: (https://github.com/zenwave360/zenwave-sdk)

Springwolf

 It documents asynchronous APIs using the AsyncAPI specification. (Apache License 2.0).

springwolf-ui adds a web UI, much like that of Springfox, and allows easy publishing of auto-generated payload examples.

Using @AsyncListener and @AsyncPublisher any protocol can be documented, although the binding in the AsyncAPI document will remain empty. 
The protocols with native support come along with a @_ProtocolName_Binding annotation to define protocol specific properties.

Library:

pom
<dependency> <groupId>io.github.springwolf</groupId> <artifactId>springwolf-core</artifactId> <version>0.16.0</version> </dependency> <dependency> <groupId>io.github.springwolf</groupId> <artifactId>springwolf-kafka</artifactId> <version>0.16.0</version> </dependency> <dependency> <groupId>io.github.springwolf</groupId> <artifactId>springwolf-ui</artifactId> <version>0.16.0</version> </dependency>

Properties file:

application.yaml

Example Java code:

SupervisionParticipantHandler class



http://localhost:6969/onap/policy/clamp/acm/springwolf/asyncapi-ui.html

Springwolf Kafka Plugin

Automated documentation for Spring Boot application with Kafka consumers.

This plugin generates an AsyncAPI document from @KafkaListener methods. (ACM-Runtime do not using @KafkaListener).