CloudEvents Java API

Java API for CloudEvents(https://github.com/cloudevents/spec)

Features

• Standard Java Bean for cloud events
• Builder Pattern to build events
• Json support by Jackson adapter
• CloudEvents JSON Schema: https://github.com/linux-china/cloud-events-java-api/blob/master/cloud-events-schema.json

How to use

• Extend CloudEvent class:

public class LoginEvent extends CloudEvent<String> {
    public LoginEvent(String email, String ip) {
        setData(email);
        setContentType("text/plain");
        setExtension("ip", ip);
    }
}

• Create object directly

CloudEvent<String> loginEvent = new CloudEvent<String>("text/plain", "jacky.chenlb@alibaba-inc.com");

• Event Builder

CloudEvent<String> loginEvent = CloudEventBuilder.<String>newInstance().contentType("text/plain").data("jacky.chenlb@alibaba-inc.com").build();

ObjectMapper

• ObjectMapper creation

  ObjectMapper objectMapper = new ObjectMapper();
  objectMapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
  objectMapper.enable(SerializationFeature.INDENT_OUTPUT);

• write as String

  objectMapper.writeValueAsString(loginEvent);

• read from json text

  objectMapper.readValue(jsonText, new TypeReference<CloudEvent<String>>() {});

Protocol Buffer

Please refer CloudEventMapper for converter between JavaBean and ProtoMessage.

Event Logging

CloudEvent ships with default toString pattern: CloudEvent{cloudEventsVersion=’0.1’,eventID=’xxx’}

12:49:22,076 |-INFO in ch.qos.logback.classic.LoggerContext[default] - CloudEvent{cloudEventsVersion='0.1',eventID='xxx'}

Event Broker

Please consider NATS or NATS Streaming to post or subscribe cloud events.

References

• CloudEvents Specification: https://github.com/cloudevents/spec
• CloudEvents Date format: https://tools.ietf.org/html/rfc3339
• NATS: https://nats.io/