docs/en/instructions/eventmesh-runtime-protocol.md

TCP Protocol Document In Eventmesh-Runtime

1. Protocol Format

dataFlow

Protocol Specification

Magic Code: 9 bit, defaultValue:EventMesh

Protocol Version: 4 bit, defaultValue:0000

Message Size: 4 bit, the total length of message

Header Size: 4 bit，the length of Message Header

Message Header: the specific header content of message 

Message Body: the specific body content of message

2. Message Object in business logic layer

Message Composition

The class of Package.java is message object in business logic layer. It contains two parts: header and body.

public class Package {

    private Header header;
    private Object body;
}


public class Header {

    private Command cmd;
    private int code;
    private String msg;
    private String seq;
}

Specificatiion

Message Header(header): The field of Command in Header, used to distinguishing different message types.

Message Body(body): The message body is defined as different objects according to the message type.

Command	type of Body
HEARTBEAT_REQUEST, HEARTBEAT_RESPONSE, HELLO_RESPONSE, CLIENT_GOODBYE_REQUEST, CLIENT_GOODBYE_RESPONSE, SERVER_GOODBYE_REQUEST, SERVER_GOODBYE_RESPONSE, LISTEN_REQUEST, LISTEN_RESPONSE, UNSUBSCRIBE_REQUEST, SUBSCRIBE_RESPONSE, UNSUBSCRIBE_RESPONSE, ASYNC_MESSAGE_TO_SERVER_ACK, BROADCAST_MESSAGE_TO_SERVER_ACK	--
HELLO_REQUEST	UserAgent
SUBSCRIBE_REQUEST	Subscription
REQUEST_TO_SERVER, REQUEST_TO_CLIENT, RESPONSE_TO_SERVER, RESPONSE_TO_CLIENT, ASYNC_MESSAGE_TO_SERVER, ASYNC_MESSAGE_TO_CLIENT, BROADCAST_MESSAGE_TO_SERVER, BROADCAST_MESSAGE_TO_CLIENT, ASYNC_MESSAGE_TO_CLIENT_ACK, BROADCAST_MESSAGE_TO_CLIENT_ACK, RESPONSE_TO_CLIENT_ACK, REQUEST_TO_CLIENT_ACK	OpenMessage
REDIRECT_TO_CLIENT	RedirectInfo

3. The Interactive Command between Client and Server(Eventmesh-Runtime)

public enum Command {

    //HeartBeat
    HEARTBEAT_REQUEST(0),                              //client send heartbeat request to server
    HEARTBEAT_RESPONSE(1),                             //server reply heartbeat response to client

    //Hello
    HELLO_REQUEST(2),                                  //client send connect request to server
    HELLO_RESPONSE(3),                                 //server reply connect response to client

    //Disconncet
    CLIENT_GOODBYE_REQUEST(4),                         //client send disconnect request to server
    CLIENT_GOODBYE_RESPONSE(5),                        //server reply disconnect response to client
    SERVER_GOODBYE_REQUEST(6),                         //server send disconncet request to client
    SERVER_GOODBYE_RESPONSE(7),                        //client reply disconnect response to server

    //Subscribe and UnSubscribe
    SUBSCRIBE_REQUEST(8),                              //client send subscribe request to server
    SUBSCRIBE_RESPONSE(9),                             //server reply subscribe response to client
    UNSUBSCRIBE_REQUEST(10),                           //client send unsubscribe request to server
    UNSUBSCRIBE_RESPONSE(11),                          //server reply unsubscribe response to client

    //Listen
    LISTEN_REQUEST(12),                            	   //client send listen request to server
    LISTEN_RESPONSE(13),                               //server reply listen response to client

    //send sync message
    REQUEST_TO_SERVER(14),                             //client(Producer) send sync msg to server
    REQUEST_TO_CLIENT(15),                             //server push sync msg to client(Consumer)
    REQUEST_TO_CLIENT_ACK(16),                         //client(Consumer) send ack of sync msg to server
    RESPONSE_TO_SERVER(17),                            //client(Consumer) send reply msg to server
    RESPONSE_TO_CLIENT(18),                            //server push reply msg to client(Producer)
    RESPONSE_TO_CLIENT_ACK(19),                        //client(Producer) send ack of reply msg to server

    //send async message
    ASYNC_MESSAGE_TO_SERVER(20),                       //client send async msg to server
    ASYNC_MESSAGE_TO_SERVER_ACK(21),                   //server reply ack of async msg to client
    ASYNC_MESSAGE_TO_CLIENT(22),                       //server push async msg to client
    ASYNC_MESSAGE_TO_CLIENT_ACK(23),                   //client reply ack of async msg to server

    //send broadcast message
    BROADCAST_MESSAGE_TO_SERVER(24),                   //client send broadcast msg to server
    BROADCAST_MESSAGE_TO_SERVER_ACK(25),               //server reply ack of broadcast msg to client
    BROADCAST_MESSAGE_TO_CLIENT(26),                   //server push broadcast msg to client
    BROADCAST_MESSAGE_TO_CLIENT_ACK(27),               //client reply ack of broadcast msg to server

    //redirect
    REDIRECT_TO_CLIENT(30),                            //server send redirect instruction to client
}

4. Client initiates interaction

Scene	Client Send	Server Reply
Hello	HELLO_REQUEST	HELLO_RESPONSE
Heartbeat	HEARTBEAT_REQUEST	HEARTBEAT_RESPONSE
Subscribe	SUBSCRIBE_REQUEST	SUBSCRIBE_RESPONSE
Unsubscribe	UNSUBSCRIBE_REQUEST	UNSUBSCRIBE_RESPONSE
Listen	LISTEN_REQUEST	LISTEN_RESPONSE
Send sync msg	REQUEST_TO_SERVER	RESPONSE_TO_CLIENT
Send reply msg of sync msg	RESPONSE_TO_SERVER	--
Send async msg	ASYNC_MESSAGE_TO_SERVER	ASYNC_MESSAGE_TO_SERVER_ACK
Send broadcast msg	BROADCAST_MESSAGE_TO_SERVER	BROADCAST_MESSAGE_TO_SERVER_ACK
Client start disconnect	CLIENT_GOODBYE_REQUEST	CLIENT_GOODBYE_RESPONSE

5. Server initiates interaction

Scene	Server Send	Client Reply
Push sync msg to client	REQUEST_TO_CLIENT	REQUEST_TO_CLIENT_ACK
Push reply msg of sync msg to client	RESPONSE_TO_CLIENT	RESPONSE_TO_CLIENT_ACK
Push async msg to client	ASYNC_MESSAGE_TO_CLIENT	ASYNC_MESSAGE_TO_CLIENT_ACK
Push broadcast msg to client	BROADCAST_MESSAGE_TO_CLIENT	BROADCAST_MESSAGE_TO_CLIENT_ACK
Server start disconnect	SERVER_GOODBYE_REQUEST	--
Server send redirect	REDIRECT_TO_CLIENT	--

6. Message classification

Send sync msg

rr-msg

Send async msg

async-msg

Send broadcast msg

broadcast-msg

HTTP Protocol Document In Eventmesh-Runtime

The class of LiteMessage.java is message definition in http protocal of EventMesh-Runtime.If you want to send msg by using http protocol,you can use client in eventmesh-sdk-java, and you just need care the specific protocol in the field of content.

public class LiteMessage {

    private String bizSeqNo;

    private String uniqueId;

    private String topic;

    private String content;

    private Map<String, String> prop;

    private long createTime = System.currentTimeMillis();
}

1. Message Send and Message Composition

Request Method: POST

Message Composition: RequestHeader + RequestBody

Heartbeat Msg

RequestHeader

Key	Description
Env	Enviroment of Client
Region	Region of Client
Idc	IDC of Client
Dcn	DCN of Client
Sys	Subsystem ID of Client
Pid	Client Process ID
Ip	Client Ip
Username	Client username
Passwd	Client password
Version	Protocol version
Language	Develop language
Code	Request Code

RequestBody

Key	Description
clientType	Producer:clientType is ClientType.PUB,Consumer:clientType is ClientType.SUB
heartbeatEntities	Heartbeat content,contains topic,url...

Subscribe Msg

RequestHeader

same with RequestHeader of heartbeat msg

RequestBody

Key	Description
topic	topic of client want to subscribe
url	url of client, server push msg to the url when receiving msg from other components

Unsubscribe Msg

RequestHeader

same with RequestHeader of Heartbeat Msg

RequestBody

same with RequestBody of Subscribe Msg

Send async msg

RequestHeader

same with RequestHeader of Heartbeat Msg

RequestBody

Key	Description
topic	topic of msg
content	msg content
ttl	timeout time of msg
bizSeqNo	biz sequence number of msg
uniqueId	unique mark of msg

2. Client initiates interaction

Scene	Client Send	Server Reply
Heartbeat	HEARTBEAT(203)	SUCCESS(0)/EVENTMESH_HEARTBEAT_ERROR(19)
Subscribe	SUBSCRIBE(206)	SUCCESS(0)/EVENTMESH_SUBSCRIBE_ERROR(17)
Unsubscribe	UNSUBSCRIBE(207)	SUCCESS(0)/EVENTMESH_UNSUBSCRIBE_ERROR(18)
Send async msg	MSG_SEND_ASYNC(104)	SUCCESS(0)/EVENTMESH_SEND_ASYNC_MSG_ERR(14)

3. Server initiates interaction

Scene	Server Send	Client Reply	Remark
Push async msg to client	HTTP_PUSH_CLIENT_ASYNC(105)	retCode	retCode=0,send success