micronaut 学习 二 创建一个简单的服务

Posted 2021-03-25 rongfengliang-荣锋亮

micronaut 提供的cli 很方便，我们可以快速创建具有所需特性的应用，以下是一个简单的web server app

创建命令

mn create-app hello-world

效果

mn create-app hello-world

| Generating Java project...

| Application created at /Users/dalong/mylearning/micronaut-project/hello-world

启动服务

./gradlew run

添加简单代码

src/main/java/hello/world/HelloController.java

package hello.world;

import io.micronaut.http.MediaType;

import io.micronaut.http.annotation.Controller;

import io.micronaut.http.annotation.Get;

​

@Controller("/hello") 

public class HelloController {

​

    @Get(produces = MediaType.TEXT_PLAIN) 

    public String index() {

        return "Hello World"; 

    }

}

访问效果

curl http://localhost:8080/hello

Hello World%

 

集成测试

• 测试controller
  使用httpclient

package hello.world;

import io.micronaut.context.annotation.Property;

import io.micronaut.http.HttpRequest;

import io.micronaut.http.client.HttpClient;

import io.micronaut.http.client.annotation.Client;

import io.micronaut.runtime.server.EmbeddedServer;

import io.micronaut.test.annotation.MicronautTest;

import org.junit.jupiter.api.Test;

​

import javax.inject.Inject;

​

import static org.junit.jupiter.api.Assertions.assertEquals;

​

@MicronautTest

class HelloControllerSpec {

    @Inject

    EmbeddedServer server; 

​

    @Inject

    @Client("/")

    HttpClient client; 

​

    @Test

    void testHelloWorldResponse() {

        String response = client.toBlocking() 

                .retrieve(HttpRequest.GET("/hello"));

        assertEquals("Hello World", response); //)

    }

}

• 测试service

package hello.world;

​

import io.micronaut.test.annotation.MicronautTest;

import javax.inject.Inject;

import org.junit.jupiter.api.Test;

import static org.junit.jupiter.api.Assertions.assertEquals;

​

@MicronautTest

public class HelloClientSpec {

​

    @Inject

    HelloClient client;

​

    @Test

    public void testHelloWorldResponse(){

        assertEquals("Hello World", client.hello().blockingGet());

    }

}

 

 

打包应用

./gradlew assemble 

效果

 

 

部署打包软件

java -jar build/libs/hello-world-0.1-all.jar 

 

效果：

hello-world java -jar build/libs/hello-world-0.1-all.jar 

16:20:24.013 [main] INFO io.micronaut.runtime.Micronaut - Startup completed in 2009ms. Server Running: http://localhost:8080

docker 运行

默认micronaut 生成的项目包含了一个dockerfile ，我添加了一个docker-compose 文件
dockerfile

 

FROM adoptopenjdk/openjdk11-openj9:jdk-11.0.1.13-alpine-slim

COPY build/libs/hello-world-*-all.jar hello-world.jar

EXPOSE 8080

CMD java -Dcom.sun.management.jmxremote -noverify ${JAVA_OPTS} -jar hello-world.jar

 

version: "3"

services:

  app:

     image: dalongrong/micronaut-hello-world

     build: ./

     ports:

     - "8080:8080"

运行&&效果

docker-compose up -d

 

效果：

Creating network "hello-world_default" with the default driver

Building app

Step 1/4 : FROM adoptopenjdk/openjdk11-openj9:jdk-11.0.1.13-alpine-slim

jdk-11.0.1.13-alpine-slim: Pulling from adoptopenjdk/openjdk11-openj9

4fe2ade4980c: Pull complete

1ba2a07c78f2: Pull complete

944724f145c9: Pull complete

1cb512dae36f: Pull complete

Digest: sha256:60718fa9eb6b6bc4ab6fe7f3a9db31b8725fb63ebdda833a43f541c07792ff5c

Status: Downloaded newer image for adoptopenjdk/openjdk11-openj9:jdk-11.0.1.13-alpine-slim

 ---> f3f4b8ddca6f

Step 2/4 : COPY build/libs/hello-world-*-all.jar hello-world.jar

 ---> b794f9b8e0d4

Step 3/4 : EXPOSE 8080

 ---> Running in d3e19ae06642

Removing intermediate container d3e19ae06642

 ---> 2f4abdc6ddfd

Step 4/4 : CMD java -Dcom.sun.management.jmxremote -noverify ${JAVA_OPTS} -jar hello-world.jar

 ---> Running in 5958c2868e24

Removing intermediate container 5958c2868e24

 ---> 44c4289cb2b6

Successfully built 44c4289cb2b6

Successfully tagged dalongrong/micronaut-hello-world:latest

WARNING: Image for service app was built because it did not already exist. To rebuild this image you must use `docker-compose build` or `docker-compose up --build`.

Creating hello-world_app_1 ... done

访问：

curl http://localhost:8080/hello 

Hello World% 

参考资料

https://docs.micronaut.io/snapshot/guide/index.html
https://github.com/rongfengliang/micronaut-hello-world