[计网]基于gunicorn的简单web服务器

1. what is gunicorn#

1.1 definition#

Gunicorn 'Green Unicorn' is a Python WSGI HTTP Server for UNIX. It's a pre-fork worker model. The Gunicorn server is broadly compatible with various web frameworks, simply implemented, light on server resources, and fairly speedy.

1.2 characteristics#

Gunicorn是基于prefork模式的Python wsgi应用服务器，支持 Unix like的系统
采用epoll (Linux下) 非阻塞网络I/O 模型
多种Worker类型可以选择同步的，基于事件的（gevent tornado等），基于多线程的
高性能，比之uwsgi不相上下
配置使用非常简单
支持 Python 2.x >= 2.6 or Python 3.x >= 3.2

2. how to use#

2.1 install#

1	pip install gunicorn

2.2 start#

1	$ gunicorn [options] module_name:variable_name

module_name对应python文件，variable_name对应web应用实例

2.3 基础example#

编写简单的myapp.py:

def app(version, start_response):
    logging.info("version: %s" % version)
    data = b"hello, world! \n"
    start_response("200 OK", [
        ("Content-Type", "text/plain"),
        ("Content-Length", str(len(data)))
        ])
    return iter([data])

启动gunicorn

1	gunicorn myapp:app -b localhost:8080

使用curl访问8080端口

1 2	$ curl localhost:8080 hello, world!

2.4 使用flask搭建简单的web服务器#

编写myflask.py

from flask import Flask
app = Flask(__name__)

@app.route('/demo', methods=['GET'])
def demo():
    return "gunicorn and flask demo.\n"

本地简单的文件组织结构如下:

$ ls -lh
total 4.0K
drwxr-xr-x 2 xxx xxx  92 Oct 18 15:12 log
drwxr-xr-x 2 xxx xxx 120 Oct 18 17:41 script
-rw-r--r-- 1 xxx xxx 657 Oct 18 14:16 start.sh

为了启动方便, 写个简单的start.sh启动脚本如下

lsof -i :$2|grep gunicorn|awk '{print $2}'|xargs kill -9   # kill掉原来该端口上 gunicorn进程

cd script 
if [ -z "$3" ]; then    
    nohup gunicorn --workers=1 $1:app -b localhost:$2 1>../log/log.${2}_${1} 2>&1 &     # 未指定进程数
else
    nohup gunicorn --workers=$3 $1:app -b localhost:$2 1>../log/log.${2}_${1} 2>&1 &    
fi

sleep 1.5s

info=`lsof -i :$2|grep gunicorn`
# echo ${info}
if [ -z "$info" ]; then
    echo "Something wrong~ Fail to start gunicorn!"
else
    echo "succeed starting gunicorn which port is $2 and which script's name is $1"
fi

启动2个gunicorn进程, 监听8090端口

1
2
3

$ sh start.sh myflask 8090 2

succeed starting gunicorn which port is 8090 and which script's name is myflask

测试下是否ok

1 2	$ curl localhost:8090/demo gunicorn and flask demo.

至此，一个基于flask和gunicorn的简单web server就搭建完成了.

LiuWen's Blogs