为什么要使用 Docker-compose

在微服务架构的应用中，一般都会有若干个微服务，每个微服务都会部署多个实例，如果每个实例都要我们手动启动的话，运维的工作量会非常的大，而docker-compose 的作用就是来管理这些实例，可以按照一定的业务规则批量启动这些实例，docker-compose 是一个编排多容器分布式部署的工具，提供命令集管理容器体弱应 用的完整开发周器，其中有构建，启动和停止。

Docker-compose 安装

# 最新地址
# https://github.com/docker/compose/releases
# 下载docker-compos
sudo curl -L "https://github.com/docker/compose/releases/download/1.24.1/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
# 为docker-compos 赋予可执行权限
chmod +x /usr/local/bin/docker-compos

安装成功！

卸载docker-compose rm /usr/local/bin/docker-compose

Docker-compose 的使用

Docker-compose 只有在多容器的时候，才能体现出来作用，所以这一次实验的项目为一个简单的 go+nginx 。

准备工作

	# 在当前目录下
	mkdir -p ./docker-compose
	cd docker-compose
	wget -c https://nginx.org/download/nginx-1.12.2.tar.gz 
	mkdir -p ./nginx/conf
	touch ./docker-compose.yml
	touch ./nginx/conf/nginx.conf
	touch ./hello_dockerfile
	touch ./nginx_dockerfile 
	touch ./start.sh
	chmod +x ./start.sh

准备docker-compose.yml 内容

version: '3'
services:
  nginx:
   image: compose_nginx:1.0
   ports:
    - 80:80
   links:
    - compose_hello
   volumes:
    - ./nginx/conf/nginx.conf:/usr/local/nginx/conf/nginx.conf
  compose_hello:
    image: compose_hello:1.0
    expose:
      - "8080"

准备一个go应用

# hello_dockerfile
FROM centos:7
MAINTAINER frost <ycr1997@163.com>
ADD hello_world hello
RUN chmod +x hello
EXPOSE 8080
CMD ./hello

准备一个nginx 服务器

步骤可以查看：Docker | dockerfile 文件编写

# nginx_dockerfile
# base image
FROM centos:7

# MAINTAINER
MAINTAINER frost <ycr1997@163.com>

# put nginx-1.12.2.tar.gz into /usr/local/src and unpack nginx
ADD nginx-1.12.2.tar.gz /usr/local/src

# running required command
RUN yum install -y gcc gcc-c++ glibc make autoconf openssl openssl-devel 
RUN yum install -y libxslt-devel -y gd gd-devel GeoIP GeoIP-devel pcre pcre-devel
RUN useradd -M -s /sbin/nologin nginx

# change dir to /usr/local/src/nginx-1.12.2
WORKDIR /usr/local/src/nginx-1.12.2

# execute command to compile nginx
RUN ./configure --user=nginx --group=nginx --prefix=/usr/local/nginx --with-file-aio  --with-http_ssl_module  --with-http_realip_module    --with-http_addition_module    --with-http_xslt_module   --with-http_image_filter_module    --with-http_geoip_module  --with-http_sub_module  --with-http_dav_module --with-http_flv_module    --with-http_mp4_module --with-http_gunzip_module  --with-http_gzip_static_module  --with-http_auth_request_module  --with-http_random_index_module   --with-http_secure_link_module   --with-http_degradation_module   --with-http_stub_status_module && make && make install

ENV PATH /usr/local/nginx/sbin:$PATH

EXPOSE 80

ENTRYPOINT ["nginx"]

CMD ["-g","daemon off;"]

准备nginx.conf 文件内容

#user  nobody;
worker_processes  1;

#error_log  logs/error.log;
#error_log  logs/error.log  notice;
#error_log  logs/error.log  info;

#pid        logs/nginx.pid;


events {
    worker_connections  1024;
}


http {
    include       mime.types;
    default_type  application/octet-stream;

    #log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
    #                  '$status $body_bytes_sent "$http_referer" '
    #                  '"$http_user_agent" "$http_x_forwarded_for"';

    #access_log  logs/access.log  main;

    sendfile        on;
    #tcp_nopush     on;

    #keepalive_timeout  0;
    keepalive_timeout  65;

    #gzip  on;

    server {
        listen       80;
        server_name  localhost;

        #charset koi8-r;

        #access_log  logs/host.access.log  main;

        location / {
        	proxy_pass http://compose_hello:8080;
    		}

        #error_page  404              /404.html;

        # redirect server error pages to the static page /50x.html
        #
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }

        # proxy the PHP scripts to Apache listening on 127.0.0.1:80
        #
        #location ~ \.php$ {
        #    proxy_pass   http://127.0.0.1;
        #}

        # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
        #
        #location ~ \.php$ {
        #    root           html;
        #    fastcgi_pass   127.0.0.1:9000;
        #    fastcgi_index  index.php;
        #    fastcgi_param  SCRIPT_FILENAME  /scripts$fastcgi_script_name;
        #    include        fastcgi_params;
        #}

        # deny access to .htaccess files, if Apache's document root
        # concurs with nginx's one
        #
        #location ~ /\.ht {
        #    deny  all;
        #}
    }


    # another virtual host using mix of IP-, name-, and port-based configuration
    #
    #server {
    #    listen       8000;
    #    listen       somename:8080;
    #    server_name  somename  alias  another.alias;

    #    location / {
    #        root   html;
    #        index  index.html index.htm;
    #    }
    #}


    # HTTPS server
    #
    #server {
    #    listen       443 ssl;
    #    server_name  localhost;

    #    ssl_certificate      cert.pem;
    #    ssl_certificate_key  cert.key;

    #    ssl_session_cache    shared:SSL:1m;
    #    ssl_session_timeout  5m;

    #    ssl_ciphers  HIGH:!aNULL:!MD5;
    #    ssl_prefer_server_ciphers  on;

    #    location / {
    #        root   html;
    #        index  index.html index.htm;
    #    }
    #}
}

准备start.sh 文件内容

# 制作 nginx 镜像
docker build -f ./nginx_dockerfile -t compose_nginx:1.0 .
# 镜作 应用 hello 镜像
docker build -f ./hello_dockerfile -t compose_hello:1.0 .
# 批量启动容器
docker-compose up

验证