Detailed explanation of how to automatically generate docker nginx reverse proxy configuration using python

由于在测试环境上用docker部署了多个应用，而且他们的端口有的相同，有的又不相同，数量也比较多，在使用jenkins发版本的时候，不好配置，于是想要写一个脚本，能在docker 容器创建、停止的时候，自动生成nginx反向代理，然后reload nginx

我的原则是尽量简单，轻量，内存占用少

目标很明确，只要能监听到docker的容器启动/停止事件，即可

网上查了一下可以用docker events来监听docker事件，试了一下，发现基本可以满足，于是用python写了一段程序，用来监听docker事件

python

#!/usr/bin/python# coding: utf8import osimport jsonimport reimport subprocessdef override(path, text):
    if not os.path.exists(path) and os.path.exists(path+"_temp"):
        os.rename(path+"_temp",path)
    fw = open(path+"_temp", 'wb')
    fw.write(text)
    fw.close()    if os.path.exists(path):
        os.remove(path)
    os.rename(path+"_temp", path)def read(path):
    try:
        fr = open(path, "rb")    except IOError:        print "The file don't exist, Please double check!"
        return
    lines = fr.readlines()
    ret = ''
    for line in lines:
        ret += line    return retdef read_jsonfile(path):
    return json.loads(read(path))def cmd(command):
    return os.popen(command).read()def get_name(container):
    return cmd("docker inspect -f '{{.Name}}' " + container).replace("/", "").replace('\n', '')def get_ip(container):
    return cmd("docker inspect -f '{{.NetworkSettings.IPAddress}}' " + container).replace('\n', '')def get_port(container):
    return cmd("docker inspect -f '{{.Config.ExposedPorts}}' " + container).replace('/tcp:{}]', '').replace('map[', '').replace('\n', '')def get_info(container):
    filename = "/var/lib/docker/containers/" + container + "/config.v2.json"
    config = read_jsonfile(filename)

    name = config['Name'].replace("/", "")
    port = config['Config']['ExposedPorts'].keys()[0].replace('/tcp', '')
    ip = cmd("docker inspect -f '{{.NetworkSettings.IPAddress}}' " + name)    # ip = config['NetworkSettings']['Networks']['bridge']['IPAddress']

    ret = {'name': name, 'port': port, 'ip': ip}    return ret


tpl = """
    server {
        listen 80;
        server_name $name.test.com;
        location / {
        proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header Host $http_host;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_pass http://$ip:$port;
        }
    }
"""def generate_conf():
    print "generate_conf"
    out = cmd("docker ps | grep -v CONTAINER | awk '{print $1}'")
    containers = out.split("\n")
    servers = ''
    hosts = ''
    for con in containers:        if con != '':
            name = get_name(con)
            ip = get_ip(con)
            port = get_port(con)            print ip, port            if len(port) >= 2:
                servers += tpl.replace("$name", name).replace("$ip", ip).replace("$port", port)
                hosts += "11.12.13.14 " + name + ".test.com\n"
    override('/usr/local/openresty/nginx/conf/vhost.conf', servers)
    override(&#39;/usr/local/openresty/nginx/html/vhost.html&#39;, "<pre class="brush:php;toolbar:false">" + hosts + "

")def reload_nginx(): print "reload nginx" cmd('nginx -s reload')def auto_reload(): generate_conf() reload_nginx()print " ==================== docker events ==================== "# auto_reload()proc = subprocess.Popen(["docker", "events"], # shell=True, # windows: true, linux: false stdout=subprocess.PIPE)while 1: out = proc.stdout.readline() event = re.sub('\(|\)', "", out).split(" ") if out.find('container stop') != -1: auto_reload() print ' container stop ' elif out.find('container start') != -1: auto_reload() print ' start container ' if out == '': print "out " break

启动命令：

nohup ./docker.py > /dev/null 2>&1 &

程序会在后台运行，断开ssh也不会结束

主要就是生成一个 conf 文件，这个文件要在nginx.conf里面引入，然后每次有容器启动/停止都生成这个文件，然后重启nginx，我这了还把容器名加上一个域名，组合成了一个子域名，然后把对应的映射关系生成了一个html文件，通过浏览器可以访问这个文件，然后把对应的代码 复制到本机的 hosts 文件里面，可以实现通过域名访问应用，当然只是开发测试的时候会这么做，但是也足够了。

The above is the detailed content of Detailed explanation of how to automatically generate docker nginx reverse proxy configuration using python. For more information, please follow other related articles on the PHP Chinese website!