d10024-non-blocking-mode-5-async-mode-vertx-style.md

D10024 - Non-Blocking, Mode 5 Async Mode ( vert.x style )

This mode is very important in zero system, because we prefer to recommend use this mode in your development. Because vert.x is non-blocking and async, this mode is based on vert.x async multi threads, if you use this mode to do development works, you can be very smart to finish all the business requirements.

From architecture of zero system, this mode contains following advantages:

• You can use all the native async clients that vert.x provided directly such as MongoClient, MySqlClient, RedisClientetc.
• All the request works should be async mode and the performance is better.
• You can do some reactive programming with Rxjava2 instead of others.
• You can use UtilityX package that zero system provided to do complex business requirements or frequently requirements.

1. Introduction

The workflow of this mode is the same as Mode 4, but there are some difference in programming. There are both sender and consumer in current mode, and the response will reply the processed result.

Request -> Agent -> @Address ( Sender ) -> 
    EventBus -> 
        @Address ( Consumer with MessageHandler ) -> Worker -> Response

Demo projects:

• Standalone - 6083: up-rhea

2. Source Code

2.1. Sender

package up.god.micro.async;

import io.vertx.core.json.JsonObject;
import io.vertx.up.annotations.Address;
import io.vertx.up.annotations.EndPoint;

import javax.ws.rs.POST;
import javax.ws.rs.Path;

@EndPoint
@Path("/api")
public class VertxStyleActor {

    @POST
    @Path("request/vertx/handler")
    @Address("ZERO://ASYNC/VERTX/HANDLER")
    public JsonObject sayHandler(final JsonObject data) {
        data.put("agent", "HANDLER");
        return data;
    }

    @POST
    @Path("request/vertx/future")
    @Address("ZERO://ASYNC/VERTX/FUTURE")
    public JsonObject sayFuture(final JsonObject data) {
        data.put("agent", "FUTURE");
        return data;
    }
}

2.2. Consumer

package up.god.micro.async;

import io.vertx.core.Future;
import io.vertx.core.eventbus.Message;
import io.vertx.core.json.JsonObject;
import io.vertx.up.aiki.Ux;
import io.vertx.up.annotations.Address;
import io.vertx.up.annotations.Queue;
import io.vertx.up.atom.Envelop;

@Queue
public class VertxStyleWorker {


    @Address("ZERO://ASYNC/VERTX/HANDLER")
    public void sayMessage(final Message<Envelop> message) {
        final JsonObject data = Ux.getBody(message);
        message.reply(Envelop.success(data));
    }

    @Address("ZERO://ASYNC/VERTX/FUTURE")
    public Future<JsonObject> sayFuture(final Envelop envelop) {
        final JsonObject data = envelop.data();
        return Future.succeededFuture(data);
    }
}

Programming Rules

1. The worker class must be annotated with io.vertx.up.annotations.Queue.
2. You must use io.vertx.up.annotations.Address annotation to set address of string type in Sender/Consumer both.
3. Address value should be the same shared in Sender/Consumer.
4. The worker method signature should be as following:
   1. void method(Message<Envelop>)
   2. Future<T> method(Envelop)
   3. Future<Envelop> method(Envelop)

3. Console

......
[ ZERO ] ( 2 Event ) The endpoint up.god.micro.async.VertxStyleActor scanned 2 events of Event, \
    will be mounted to routing system.
......
[ ZERO ] ( 6 Queue ) The Zero system has found 6 components of @Queue.
......
[ ZERO ]        Addr : ZERO://ASYNC/VERTX/FUTURE
[ ZERO ]        Addr : ZERO://ASYNC/VERTX/HANDLER
......
[ ZERO ] ( 2 Receipt ) The queue up.god.micro.async.VertxStyleWorker scanned 2 records of Receipt, \
    will be mounted to event bus.
......
[ ZERO ] ( Uri Register ) "/api/request/vertx/future" has been deployed by ZeroHttpAgent, Options = Route...
[ ZERO ] ( Uri Register ) "/api/request/vertx/handler" has been deployed by ZeroHttpAgent, Options = Route...
......

4. Testing

4.1. Message Request

URL : http://localhost:6083/api/request/vertx/handler

Method : POST

Request :

{
    "username":"lang.yu",
    "email":"lang.yu@hpe.com"
}

Response :

{
    "data": {
        "username": "lang.yu",
        "email": "lang.yu@hpe.com",
        "agent": "HANDLER"
    }
}

4.2. Future Request

URL : http://localhost:6083/api/request/vertx/future

Method : POST

Request :

{
    "username":"lang.yu",
    "email":"lang.yu@hpe.com"
}

Response :

{
    "data": {
        "username": "lang.yu",
        "email": "lang.yu@hpe.com",
        "agent": "FUTURE"
    }
}

5. Summary

Current mode is standard vert.x mode and we recommend to use this mode in your project. Here are a java class named Envelop and it's Uniform Resource Model that defined by zero system, it could take many information to go through from agent to worker threads on event bus. The Uniform Resource Model will be introduced in future tutorials, it could help developers to simply the programming in web container, service specification and restful web request, then the developers could focus on business requirements only.