docker build
docker build를 통해 Dockerfile에 명시된 설정대로 image를 생성한다. 생성된 이미지는 docker run을 통해 컨테이너에 담겨 실행된다.
Spring boot
로컬 환경에서 개발하고 있는 Spring boot 프로젝트를 도커 컨테이너에 올리려고 다음과 같은 방법을 사용했다.
일단 테스트를 위해 HelloWorld를 출력하는 컨트롤러를 하나 만들었다.
package com.dockertutorial.example;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
@RequestMapping("")
public class HelloWorld {
@GetMapping("")
public String ReturnHello() {
return "HelloWorld";
}
}그런다음 ./gradlew build로 프로젝트를 빌드하여 jar파일을 만들고, 프로젝트 루트에 만들어놓은 Dockerfile을 실행하여 image를 생성했다.
# Dockerfile
FROM openjdk:17
ARG JAR_FILE=build/libs/*-SNAPSHOT.jar
COPY ${JAR_FILE} app.jar
ENTRYPOINT ["java", "-jar", "/app.jar"]java 17버전을 사용했다.
image를 생성하기 위해 프로젝트 루트에서 다음과 같은 명령어를 실행했다.
ubuntu@DESKTOP-GMH7007:~/workspace/dockertutorial$ docker build -t dockertutorial:0.0.4 .
=> [internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 157B 0.0s
=> [internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [internal] load metadata for docker.io/library/openjdk:17 1.3s
=> [internal] load build context 0.0s
=> => transferring context: 116B 0.0s
=> [1/2] FROM docker.io/library/openjdk:17@sha256:528707081fdb9562eb819128a9f85ae7fe000e2fbaeaf9f87662e7b3f38cb7d8 0.0s
=> CACHED [2/2] COPY build/libs/*-SNAPSHOT.jar app.jar 0.0s
=> exporting to image 0.0s
=> => exporting layers 0.0s
=> => writing image sha256:de7cc8dfa14d2cfd123a6a000b383681224eb275d82567eaad6b7eda39e98c36 0.0s
=> => naming to docker.io/library/dockertutorial:0.0.4 여기까지 한다음 docker images를 실행하면 방금 생성한 이미지가 나타난다.
ubuntu@DESKTOP-GMH7007:~/workspace/dockertutorial$ docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
dockertutorial 0.0.4 de7cc8dfa14d 9 minutes ago 494MB
mysql latest 73246731c4b0 3 weeks ago 619MB
hello-world latest d2c94e258dcb 8 months ago 13.3kB생성한 image를 실행하여 컨테이너에 올리기 위해 다음과 같이 실행했다.
ubuntu@DESKTOP-GMH7007:~/workspace/dockertutorial$ docker run -d -p 10011:8080 --name dockertutorial dockertutorial:0.0.4
bf3f65653bc59ce425ec11da831c6ca49ea5647d00ed5958698649a5524e6aa2포트포워딩을 위해 8080을 10011로부터 포워딩했다. :0.0.4처럼 tag를 붙여서 image를 구분할 수 있다.
잘 실행되었는지 확인하기 위해 docker ps를 실행하면 이렇게 나온다.
ubuntu@DESKTOP-GMH7007:~/workspace/dockertutorial$ docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
bf3f65653bc5 dockertutorial:0.0.4 "java -jar /app.jar" About a minute ago Up About a minute 0.0.0.0:10011->8080/tcp, :::10011->8080/tcp dockertutorialMysql
mysql image는 원격 서버에서 받아야 한다.
docker pull mysqlmysql을 컨테이너에 그대로 올리면 바로 종료된다. docker ps -a로 확인하면 이렇다.
ubuntu@DESKTOP-GMH7007:~/workspace/dockertutorial$ docker run -d -p 10012:3306 --name database mysql:latest
a46115bed622b1153211179c281711f046cca26a1e74c85a37dcb195b76dd2e0
ubuntu@DESKTOP-GMH7007:~/workspace/dockertutorial$ docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
a46115bed622 mysql:latest "docker-entrypoint.s…" 33 seconds ago Exited (1) 32 seconds ago database포트포워딩을 10012에서 3306으로 향하도록 설정했다.
어떤 오류를 내는지 확인하기 위해 docker container logs database를 실행하면 이렇게 나온다.
ubuntu@DESKTOP-GMH7007:~/workspace/dockertutorial$ docker container logs database
2024-01-12 13:40:15+00:00 [Note] [Entrypoint]: Entrypoint script for MySQL Server 8.2.0-1.el8 started.
2024-01-12 13:40:15+00:00 [Note] [Entrypoint]: Switching to dedicated user 'mysql'
2024-01-12 13:40:15+00:00 [Note] [Entrypoint]: Entrypoint script for MySQL Server 8.2.0-1.el8 started.
2024-01-12 13:40:16+00:00 [ERROR] [Entrypoint]: Database is uninitialized and password option is not specified
You need to specify one of the following as an environment variable:
- MYSQL_ROOT_PASSWORD
- MYSQL_ALLOW_EMPTY_PASSWORD
- MYSQL_RANDOM_ROOT_PASSWORD필수적으로 설정해야하는 환경변수가 존재하기 때문에, 컨테이너에 올릴 때 항상 옵션으로 넣어야 한다. 로그에서 볼 수 있듯 세 가지 옵션 중에 하나는 무조건 넣어야 한다고 한다.
'mysql - Official Image | Docker Hub' 이 링크에서 설정할 수 있는 환경변수를 명시하고 있다.
문서를 읽어보면 MYSQL_ROOT_PASSWORD를 항상 요구하고 있다. 따라서 컨테이너를 실행할 때 이렇게 실행하면 된다.
ubuntu@DESKTOP-GMH7007:~/workspace/dockertutorial$ docker run -d -p 10012:3306 --name database -e MYSQL_ROOT_PASSWORD=password mysql:latest
7e6ae1b3f7be97bc063105de1834c1b23f0b0c4075bbc8e26f813091f152b559
ubuntu@DESKTOP-GMH7007:~/workspace/dockertutorial$ docker container logs database
2024-01-12 13:51:20+00:00 [Note] [Entrypoint]: Entrypoint script for MySQL Server 8.2.0-1.el8 started.
2024-01-12 13:51:20+00:00 [Note] [Entrypoint]: Switching to dedicated user 'mysql'
2024-01-12 13:51:20+00:00 [Note] [Entrypoint]: Entrypoint script for MySQL Server 8.2.0-1.el8 started.
2024-01-12 13:51:20+00:00 [Note] [Entrypoint]: Initializing database files
2024-01-12T13:51:20.566833Z 0 [System] [MY-015017] [Server] MySQL Server Initialization - start.
2024-01-12T13:51:20.567560Z 0 [Warning] [MY-011068] [Server] The syntax '--skip-host-cache' is deprecated and will be removed in a future release. Please use SET GLOBAL host_cache_size=0 instead.
2024-01-12T13:51:20.567597Z 0 [System] [MY-013169] [Server] /usr/sbin/mysqld (mysqld 8.2.0) initializing of server in progress as process 79
2024-01-12T13:51:20.575524Z 1 [System] [MY-013576] [InnoDB] InnoDB initialization has started.
2024-01-12T13:51:21.721999Z 1 [System] [MY-013577] [InnoDB] InnoDB initialization has ended.
docker-compose
spring boot 프로젝트와 mysql을 컨테이너에 올렸다 내렸다 하려면 명령어를 여러개 쳐야한다. 상당히 복잡한데 이걸 yml파일로 명시하여 한 번에 여러 개의 컨테이너를 생성하기 위해 docker-compose를 사용한다고 한다.
version: '3.8'
services:
db:
container_name: mysql
image: mysql:latest
environment:
MYSQL_ROOT_PASSWORD: password
MYSQL_USER: admin
MYSQL_PASSWORD: password1
MYSQL_DATABASE: TestDatabase
ports:
- '10012:3306'
app:
container_name: app
build:
context: ../
dockerfile: Dockerfile
restart: always
ports:
- '10011:8080'
depends_on:
- db
docker-compose.yml을 deploy폴더에 넣어두고 위와 같이 작성했다.
그다음 docker-compose build, docker-compose up으로 이미지 생성과 컨테이너 실행을 했다.
ubuntu@DESKTOP-GMH7007:~/workspace/dockertutorial/deploy$ docker-compose build; docker-compose up
db uses an image, skipping
Building app
[+] Building 0.9s (7/7) FINISHED docker:default
=> [internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 157B 0.0s
=> [internal] load metadata for docker.io/library/openjdk:17 0.7s
=> [internal] load build context 0.0s
=> => transferring context: 116B 0.0s
=> [1/2] FROM docker.io/library/openjdk:17@sha256:528707081fdb9562eb819128a9f85ae7fe000e2fbaeaf9f87662e7b3f38cb7d8 0.0s
=> CACHED [2/2] COPY build/libs/*-SNAPSHOT.jar app.jar 0.0s
=> exporting to image 0.0s
=> => exporting layers 0.0s
=> => writing image sha256:de7cc8dfa14d2cfd123a6a000b383681224eb275d82567eaad6b7eda39e98c36 0.0s
=> => naming to docker.io/library/deploy_app 0.0s
Recreating mysql ... done
Recreating app ... done
Attaching to mysql, app
mysql | 2024-01-12 13:59:09+00:00 [Note] [Entrypoint]: Entrypoint script for MySQL Server 8.2.0-1.el8 started.
mysql | 2024-01-12 13:59:09+00:00 [Note] [Entrypoint]: Switching to dedicated user 'mysql'
mysql | 2024-01-12 13:59:09+00:00 [Note] [Entrypoint]: Entrypoint script for MySQL Server 8.2.0-1.el8 started.
mysql | 2024-01-12 13:59:09+00:00 [Note] [Entrypoint]: Initializing database files
mysql | 2024-01-12T13:59:09.428635Z 0 [System] [MY-015017] [Server] MySQL Server Initialization - start.
mysql | 2024-01-12T13:59:09.429384Z 0 [Warning] [MY-011068] [Server] The syntax '--skip-host-cache' is deprecated and will be removed in a future release. Please use SET GLOBAL host_cache_size=0 instead.
mysql | 2024-01-12T13:59:09.429423Z 0 [System] [MY-013169] [Server] /usr/sbin/mysqld (mysqld 8.2.0) initializing of server in progress as process 80
mysql | 2024-01-12T13:59:09.446686Z 1 [System] [MY-013576] [InnoDB] InnoDB initialization has started.
mysql | 2024-01-12T13:59:10.602298Z 1 [System] [MY-013577] [InnoDB] InnoDB initialization has ended.
app |
app | . ____ _ __ _ _
app | /\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
app | ( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
app | \\/ ___)| |_)| | | | | || (_| | ) ) ) )
app | ' |____| .__|_| |_|_| |_\__, | / / / /
app | =========|_|==============|___/=/_/_/_/
app | :: Spring Boot :: (v3.2.1)
app |
app | 2024-01-12T13:59:10.949Z INFO 1 --- [ main] c.d.example.ExampleApplication : Starting ExampleApplication using Java 17.0.2 with PID 1 (/app.jar started by root in /)
app | 2024-01-12T13:59:10.953Z INFO 1 --- [ main] c.d.example.ExampleApplication : No active profile set, falling back to 1 default profile: "default"
app | 2024-01-12T13:59:11.513Z INFO 1 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat initialized with port 8080 (http)
app | 2024-01-12T13:59:11.521Z INFO 1 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat]
app | 2024-01-12T13:59:11.522Z INFO 1 --- [ main] o.apache.catalina.core.StandardEngine : Starting Servlet engine: [Apache Tomcat/10.1.17]
app | 2024-01-12T13:59:11.545Z INFO 1 --- [ main] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
app | 2024-01-12T13:59:11.546Z INFO 1 --- [ main] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 538 ms
app | 2024-01-12T13:59:11.772Z INFO 1 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat started on port 8080 (http) with context path ''
app | 2024-01-12T13:59:11.781Z INFO 1 --- [ main] c.d.example.ExampleApplication : Started ExampleApplication in 1.093 seconds (process running for 1.361)
근데 잘 되는데, 세세한 설정을 모르기 때문에 좀 더 공부가 필요하다.