dubbo-example

An example of using Apache Dubbo for microservice RPC.

This example starts both a Dubbo service and a restful web service. The Dubbo service returns Hello World! and Goodbye! messages. The Dubbo service is accessed by making an HTTP call to the restful web service, which in turn calls the Dubbo service and returns the message created by the Dubbo service.

Projects

The following projects make up this example:

• dubbo-example-api - Dubbo service API exposed by the provider
• dubbo-example-consumer - Rest service that calls API exposed by the provider
• dubbo-example-provider - Dubbo service that implements the API

Building the Example

Run the following Gradle command to build this example:

./gradlew clean build

Running the Example

Follow the steps below to run the Dubbo example:

Starting the Provider

1. In a new terminal, run the following command to start the provider:

    ./gradlew :dubbo-example-provider:run
   

   If the provider starts successfully, you will see the following in the terminal:

    2018-09-21 18:45:32.298  INFO 78749 --- [           main] dubbo.example.provider.Application       : Started Application in 1.433 seconds (JVM running for 1.8)
    2018-09-21 18:45:32.300  INFO 78749 --- [pool-1-thread-1] .d.c.e.AwaitingNonWebApplicationListener :  [Dubbo] Current Spring Boot Application is await...
   

Starting the Consumer

1. In a new terminal, run the following command to start the consumer:

    ./gradlew :dubbo-example-consumer:run
   

   If the consumer starts successfully, you will see the following in the terminal:

    2018-09-21 18:48:05.875  INFO 78789 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 8081 (http) with context path ''
    2018-09-21 18:48:05.889  INFO 78789 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 8080 (http) with context path ''
    2018-09-21 18:48:05.891  INFO 78789 --- [           main] dubbo.example.consumer.Application       : Started Application in 3.757 seconds (JVM running for 4.127)
   

Calling the Consumer

1. In a new terminal, run the following command to invoke the hello endpoint:

    curl -v http://localhost:8080/hello?name=World
   

   If the request was successful, you will receive a Hello, World! message:

    *   Trying ::1...
    * TCP_NODELAY set
    * Connected to localhost (::1) port 8080 (#0)
    > GET /hello?name=World HTTP/1.1
    > Host: localhost:8080
    > User-Agent: curl/7.54.0
    > Accept: */*
    >
    < HTTP/1.1 200
    < Content-Type: text/plain;charset=UTF-8
    < Content-Length: 13
    < Date: Sat, 22 Sep 2018 01:49:59 GMT
    <
    * Connection #0 to host localhost left intact
    Hello, World!
   

2. Run the following command to invoke the goodbye endpoint:

    curl -v http://localhost:8080/goodbye
   

   If the request was successful, you will receive a Goodbye! message:

    *   Trying ::1...
    * TCP_NODELAY set
    * Connected to localhost (::1) port 8080 (#0)
    > GET /goodbye HTTP/1.1
    > Host: localhost:8080
    > User-Agent: curl/7.54.0
    > Accept: */*
    >
    < HTTP/1.1 200
    < Content-Type: text/plain;charset=UTF-8
    < Content-Length: 8
    < Date: Sat, 22 Sep 2018 01:51:42 GMT
    <
    * Connection #0 to host localhost left intact
    Goodbye!
   

Bugs and Feedback

For bugs, questions, and discussions please use the Github Issues.

License

Copyright 2018 Greg Whitaker

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.