Python web学习：Django + uWSGI + Nginx

一、背景

由于工作需要，最近学习了下Python web的开发，现在做一个简要总结。
选用的Python web架构如下：
Python web框架：Django
应用服务器： uWSGI
代理服务器：Nginx
其中Django是最为常用的Python web框架，类似的框架还有：Flask、web2py等。

二、Django

安装Django可在网上搜索资料。

django-admin

安装完Django后，运行django-admin，得到如下结果：

创建Python web工程

运行如下命令django-admin startproject HelloWorld，可创建名为HelloWorld的Python web工程，目录结构如下：

目录说明：

• HelloWorld: 项目的根目录。
• manage.py: 一个实用的命令行工具，可让你以各种方式与该 Django 项目进行交互，例如通过命令行启动该web项目，通过pycharm启动该web项目等。
• HelloWorld/init.py: 一个空文件，告诉 Python 该目录是一个 Python 包。
• HelloWorld/settings.py: 该 Django 项目的设置/配置。
• HelloWorld/urls.py: 该 Django 项目的 URL 声明; 该web项目提供的所有接口均在这里配置。
• HelloWorld/wsgi.py: 一个 WSGI 兼容的 Web 服务器的入口，以便运行你的项目。

web项目启动

命令行窗口下执行如下命令：

python manage.py runserver 0.0.0.0:8000

0.0.0.0 让其它电脑可连接到开发服务器，8000 为端口号。如果不说明，那么端口号默认为 8000。

打开浏览器，输入http://localhost:8000/查看效果：

三、uWSGI

uWSGI是一个应用服务器，可以理解为地位和Tomcat类似，一般和Nginx配合使用，以提供HTTP服务。

uWSGI使用示例

The first WSGI application

Let’s start with a simple “Hello World” example:

def application(env, start_response):
    start_response('200 OK', [('Content-Type','text/html')])
    return [b"Hello World"]

(save it as foobar.py).

As you can see, it is composed of a single Python function. It is called “application” as this is the default function that the uWSGI Python loader will search for (but you can obviously customize it).

Deploy it on HTTP port 9090

Now start uWSGI to run an HTTP server/router passing requests to your WSGI application:

uwsgi --http :9090 --wsgi-file foobar.py

打开浏览器输入http://localhost:9090/，结果如下

Adding concurrency and monitoring

The first tuning you would like to make is adding concurrency (by default uWSGI starts with a single process and a single thread).

You can add more processes with the --processes option or more threads with the --threads option (or you can have both).

uwsgi --http :9090 --wsgi-file foobar.py --master --processes 4 --threads 2

This will spawn 4 processes (each with 2 threads), a master process (will respawn your processes when they die) and the HTTP router (seen before).

uWSGI配置

仍以上面的配置为例：

uwsgi --http :9090 --wsgi-file foobar.py --master --processes 4 --threads 2

Argh! What the hell is this?! dealing with such long command lines is unpractical, foolish and error-prone. Never fear! uWSGI supports various configuration styles. In this quickstart we will use .ini files.

[uwsgi]
socket = 127.0.0.1:3031
chdir = /home/foobar/myproject/
wsgi-file = myproject/wsgi.py
processes = 4
threads = 2
stats = 127.0.0.1:9191
A lot better!

Just run it:

uwsgi yourfile.ini

在浏览器中访问，仍可得到正确结果。

uWSGI详细资料详见本文末尾中的资料链接。

四、Nginx

配置基本和Java web中的Nginx的配置相同，配置文件如下：

# proxy conf
user                        admin;

worker_rlimit_nofile        100000;

error_log                   "/data/logs/error_log" warn;
pid                         /home/admin/logs/tengine.pid;

events {
    use                     epoll;
    worker_connections      20480;
}

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

    root                    /home/admin/htdocs;

    sendfile                on;
    tcp_nopush              on;

    server_tokens           off;

    keepalive_timeout       0;

    client_header_timeout   1m;
    send_timeout            1m;
    client_max_body_size    3m;

    error_page              506 http://your_error_page.html;

    index                   index.html index.htm;

    log_format              proxyformat    "$remote_addr $request_time_usec $http_x_readtime [$time_local] \"$request_method http://$host$request_uri\" $status $body_bytes_sent \"$http_referer\" \"$http_user_agent\" \"$md5_encode_cookie_unb\" \"$md5_encode_$cookie_cookie2\" ";

    access_log              "/data/logs/access_log" proxyformat;
    log_not_found           off;

    gzip                    on;
    gzip_http_version       1.0;
    gzip_comp_level         6;
    gzip_min_length         1024;
    gzip_proxied            any;
    gzip_vary               on;
    gzip_disable            msie6;
    gzip_buffers            96 8k;
    gzip_types              text/xml text/plain text/css application/javascript application/x-javascript application/rss+xml;

    proxy_set_header        Host $host;
    proxy_set_header        X-Real-IP $remote_addr;
    proxy_set_header        Web-Server-Type nginx;
    proxy_set_header        WL-Proxy-Client-IP $remote_addr;
    proxy_set_header        X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_redirect          off;
    proxy_buffers           128 8k;
    proxy_intercept_errors  on;

    # fight mhtml/utf-7 bug
    hat_content             "\r\n";
    hat_types               text/html text/css;

    server {
        listen              8080;
        server_name         localhost;

        location /test/tools {
            include uwsgi_params;
            uwsgi_pass 127.0.0.1:8000;
            chunked_transfer_encoding off;
        }
    }
}

其中include uwsgi_params;中的配置如下：

uwsgi_param  QUERY_STRING       $query_string;
uwsgi_param  REQUEST_METHOD     $request_method;
uwsgi_param  CONTENT_TYPE       $content_type;
uwsgi_param  CONTENT_LENGTH     $content_length;

uwsgi_param  REQUEST_URI        $request_uri;
uwsgi_param  PATH_INFO          $document_uri;
uwsgi_param  DOCUMENT_ROOT      $document_root;
uwsgi_param  SERVER_PROTOCOL    $server_protocol;
uwsgi_param  HTTPS              $https if_not_empty;

uwsgi_param  REMOTE_ADDR        $remote_addr;
uwsgi_param  REMOTE_PORT        $remote_port;
uwsgi_param  SERVER_PORT        $server_port;
uwsgi_param  SERVER_NAME        $server_name;

include uwsgi_params的作用如下：

五、资料

Django

1. https://docs.djangoproject.com/zh-hans/2.2/
2. https://www.jianshu.com/p/679dee0a4193
3. http://www.runoob.com/django/django-first-app.html

uWSGI

1. https://uwsgi-docs.readthedocs.io/en/latest/

PEP 3333 – Python Web Server Gateway Interface v1.0.1

1. https://www.python.org/dev/peps/pep-3333/