1. What is docker?
Introduction
Docker is an open source engine that can easily create a lightweight, portable, and self-sufficient container for any application. Developers can compile and test containers on their laptops and deploy them in a production environment in batches, including VMs (virtual machines), bare metal, OpenStack clusters, and other basic application platforms.
Application scenarios of docker
- Automatic packaging and publishing of web applications;
- Automated testing and continuous integration and release;
- Deploy and adjust databases or other background applications in a service-oriented environment;
- Compile or extend the existing OpenShift or Cloud Foundry platform from scratch to build your own PaaS environment.
For the use of docker, I will have a special topic to explain in detail later .
2. integrate docker
Create project
Create a springboot project springboot-docker
1. Startup
package com.gf;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
@SpringBootApplication
@RestController
public class SpringbootDockerApplication {
public static void main(String[] args) {
SpringApplication.run(SpringbootDockerApplication.class, args);
}
@GetMapping("/{name}")
public String hi(@PathVariable(value = "name") String name) {
return "hi , " + name;
}
}
2. Containerize the springboot project
We write a Dockerfile to customize the image, create a Dockerfile file under src/main/resources/docker
FROM frolvlad/alpine-oraclejdk8:slim
VOLUME/tmp
ADD springboot-docker-0.0.1-SNAPSHOT.jar app.jar
RUN sh -c 'touch/app.jar'
ENV JAVA_OPTS=""
ENTRYPOINT [ "sh", "-c", "java $JAVA_OPTS -Djava.security.egd=file:/dev/./urandom -jar/app.jar" ]
3. pom.xml
We build the docker image through maven. In the pom directory of maven, add the plug-in built by the docker image
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.1.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.gf</groupId>
<artifactId>springboot-docker</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>springboot-docker</name>
<description>Demo project for Spring Boot</description>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
<docker.image.prefix>gf</docker.image.prefix>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
<plugin>
<groupId>com.spotify</groupId>
<artifactId>docker-maven-plugin</artifactId>
<version>1.2.0</version>
<configuration>
<imageName>${docker.image.prefix}/${project.artifactId}</imageName>
<dockerDirectory>src/main/resources/docker</dockerDirectory>
<resources>
<resource>
<targetPath>/</targetPath>
<directory>${project.build.directory}</directory>
<include>${project.build.finalName}.jar</include>
</resource>
</resources>
</configuration>
</plugin>
</plugins>
</build>
</project>
Build image
We run the following command to build the image:
mvn clean
mvn package docker:bulid
After the build is successful, we can view the image with the following command:
docker images
Start the mirror:
#c2dba352c3c1 ID
docker run -p 8080:8080 -t c2dba352c3c1
After that we can access the service.
Source download: github.com/gf-huanchup...