Docker Compose
brief introduction
In the docker we learned earlier, we operate a single container, and Dockerfile build is operated manually.
In the case of microservices, 100 microservices! If you use manual operation one by one, it is also very troublesome.
Therefore, Docker Compose can easily and efficiently manage containers and define and run multiple containers!
Introduction to the official website
Compose is a tool for defining and running multi container Docker applications. With compose, you can use YAML files to configure the services of your application. Then, use a single command to create and start all services from the configuration. To learn more about all the features of compose, see the feature list.
Compose applies to all environments: production, staging, development, testing, and CI workflows. You can learn more about each case in Common Use Cases.
Using Compose is basically a three-step process:
- Use the Dockerfile to define your application's environment so that it can be replicated anywhere.
- Define the services that make up your application, docker - compose YML so that they can run together in an isolated environment.
- Run the docker compose up and Docker compose command commands to start and run your entire application. You can also run docker compose up using the docker compose binary.
Understanding of Docker Compose
Docker Compose is to arrange multiple containers into one file.
Docker Compose installation
Under Linux environment
## 1. Run this command to download the current stable version of Docker Compose: sudo curl -L "https://github.com/docker/compose/releases/download/1.29.2/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose ## You can also install Docker Compose at high speed by executing the following command. sudo curl -L https://get.daocloud.io/docker/compose/releases/download/1.29.2/docker-compose-`uname -s`-`uname -m` > /usr/local/bin/docker-compose ## 2. Apply executable permissions to binary files: sudo chmod +x /usr/local/bin/docker-compose ##Test installation. $ docker-compose --version docker-compose version 1.29.2, build 1110ad01 ah
Common commands and configurations of Docker Compose
- ps: lists all compose run containers
docker-compose ps
- logs: view the service log output
docker-compose ps
- Port: print the public port of the binding
docker-compose port eureka 8761
- Build: build or rebuild services
docker-compose build
- start； Start a container that already exists for the specified service
docker-compose start xiaomingapp
- stop: the container that stops the running service
docker-compose stop redis
- rm: delete the container that knows the service
docker-compose rm redis
- up: build and start containers
docker-compose up
- kill: stop the container that knows the service
- run: execute a command on a service
docker-compose run web bash
- pull: download service image
- scale: sets the number of service running containers, specified in the form of service=num
docker-compose scale user=3 movie=3
docker-compos.yaml attribute
docker-compose.yaml core
Refer to the official document for specific parameters
Official documents: https://docs.docker.com/compose/compose-file/compose-file-v3/
## It is mainly divided into three layers Version -- "service" - > other configurations/ version: "" ## edition services: ## service Service 1: ## web build: ... image: networks: volumes ... Service 2: ## redis ... ## Other configuration networks / volumes, global rules volumes: network: configs:
case
version: "3.9" ## edition
services: ## service
web:
build: .
depends_on: ##Dependence. Execute db redis first
- db
- redis
redis:
image: redis
db:
image: postgres
Learning needs to master the law!
Using docker compose network
When arranging containers with docker compose, a default network will be created and defined. All containers use the network, and the containers can be connected.
xiaoming[root@cn-mbp-c02v221ahv2f java]# docker network list NETWORK ID NAME DRIVER SCOPE 25463fc507cb bridge bridge local 77b421abcbd9 host host local e5f240fc6078 java_default bridge local b7ade70af5bc mynet bridge local c2509facb374 none null local 3f39b14d72a7 redis bridge local
Using docker compose to package and deploy jar s
Write and test java web applications and only use redis for testing
@RestController
public class HelloController {
@Autowired
private RedisTemplate redisTemplate;
@RequestMapping("hello/{name}")
public String hello(@PathVariable("name") String name){
redisTemplate.opsForValue().set("name",name);
return (String) redisTemplate.opsForValue().get("name");
}
Here we use the redis service name for network connectivity
server.port=8080 spring.redis.host=redis
[root@cn-mbp-c02v221ahv2f java]# vi docker-compose.yml
version: '3.3'
services:
xiaomingapp:
image: xiaomingapp
build: .
ports:
- 8080:8080
depends_on:
- redis
redis:
image: "redis:alpine"
[root@cn-mbp-c02v221ahv2f java]# vi Dockerfile
FROM java:8
COPY *.jar /app.jar
CMD ["--server.port=8080"]
EXPOSE 8080
[root@cn-mbp-c02v221ahv2f java]# ll
total 26424
-rw-r--r--. 1 root root 168 Aug 3 01:49 docker-compose.yml
-rw-r--r--. 1 root root 108 Aug 3 01:48 Dockerfile
-rw-r--r--. 1 root root 27049938 Aug 3 01:48 hello-0.0.1-SNAPSHOT.jar
Use docker compose up -- build to build
[root@cn-mbp-c02v221ahv2f java]# docker-compose up --build [root@cn-mbp-c02v221ahv2f java]# docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES f697833af140 xiaomingapp "java -jar /app.jar ..." 4 hours ago Up 4 hours 0.0.0.0:8080->8080/tcp, :::8080->8080/tcp java_xiaomingapp_1 b1f576accdd1 redis:alpine "docker-entrypoint.s..." 4 hours ago Up 4 hours 6379/tcp java_redis_1
Test successful
[root@cn-mbp-c02v221ahv2f java]# curl localhost:8080/hello/xiaoming xiaoming