在上一章最简单理解CGI,FastCGI,WSGI  我们将fastcgi规范类比HTTP。下面我们通过一个案例更加明白fastcgi

  我们使用的是 nginx作为前端 代理,我们包装了gevent_fastcgi FastCGIServer 作为我们的FastCGI Server。

  nginx配置:

 #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 / {
root html;
index index.html index.htm;
}
# 所有以.py结尾的都发送到localhost:9000进行处理
location ~\.py{
fastcgi_pass localhost:9000;
fastcgi_param QUERY_STRING $query_string;
fastcgi_param REQUEST_METHOD $request_method;
fastcgi_param CONTENT_TYPE $content_type;
fastcgi_param CONTENT_LENGTH $content_length;
fastcgi_param SCRIPT_NAME $fastcgi_script_name;
fastcgi_param REQUEST_URI $request_uri;
fastcgi_param DOCUMENT_URI $document_uri;
fastcgi_param DOCUMENT_ROOT $document_root;
fastcgi_param SERVER_PROTOCOL $server_protocol;
fastcgi_param HTTPS $https if_not_empty;
fastcgi_param GATEWAY_INTERFACE CGI/1.1;
fastcgi_param SERVER_SOFTWARE nginx/$nginx_version;
fastcgi_param REMOTE_ADDR $remote_addr;
fastcgi_param REMOTE_PORT $remote_port;
fastcgi_param SERVER_ADDR $server_addr;
fastcgi_param SERVER_PORT $server_port;
fastcgi_param SERVER_NAME $server_name;
} #error_page 404 /404.html; # redirect server error pages to the static page /50x.html
#
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root html;
} # proxy the PHP scripts to Apache listening on 127.0.0.1:80
#
#location ~ \.php$ {
# 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;
# server_name localhost; # ssl on;
# ssl_certificate cert.pem;
# ssl_certificate_key cert.key; # ssl_session_timeout 5m; # ssl_protocols SSLv2 SSLv3 TLSv1;
# ssl_ciphers HIGH:!aNULL:!MD5;
# ssl_prefer_server_ciphers on; # location / {
# root html;
# index index.html index.htm;
# }
#} }

    下面在贴出 FasctCGI Server端的代码:

 from gevent_fastcgi.server import FastCGIServer
from gevent_fastcgi.wsgi import WSGIRequestHandler def wsgi_app(environ, start_response):
print 'Request from ', environ['HTTP_USER_AGENT']
start_response('200 OK', [('Content-type', 'text/html')])
yield '<html><head><title>test fastcgi</title></head><body>'
yield '<table border="2">'
for k, v in environ.items():
yield '<tr><td>%s</td><td>%s</td></tr>'%(k, v)
yield '</table>'
yield '</body></html>' request_handler = WSGIRequestHandler(wsgi_app)
server = FastCGIServer(('127.0.0.1', 9000), request_handler, num_workers=4)
server.serve_forever()

    使用了生成器的方式,性能比较高。

    上面的代码该一下(改成WSGIServer)马上就能切换成 WSGI Server了,我们按照WSGI的规范进行扩展一下,就是一个支持WSGI Web框架了。现在应该很清楚CGI,FastCGI,WSGI技术了吧,只要把这些技术弄明白了,我们就能随意组合HTTP Server 和 运用服务器(FastCGI Server,WSGI Server等)。

    分别运行nginx和运行上面的脚本程序.

    输入任何以.py结尾的请求,将会输出一张 FastCGI的环境变量的表。例如: localhost/script/test.py

  下面汇总一下CGI,FastCGI,WSGI相关的技术文章

   CGI    粗谈CGI

   FastCGI http://www.fastcgi.com/drupal/node/6?q=node/15

   WSGI    http://wsgi.readthedocs.org/en/latest/index.html

  以及他们之间的关系   Python Web初学解惑之 WSGI、flup、fastcgi、web.py的关系

  其实看源码和这些协议的白皮书是最好的,如果还有不明白的可以留言。关于这CGI,FastCGI,WSGI以及相关知识,我研究了一个星期, 都是直接看这些 协议 的标准说明书,也研究了很多实现了这些协议 的服务器,当然基本都是Python源码。所以大家有什么困惑可以互相交流一下。

04-14 10:15