假设我们要添加一个我们自己的middleware,用来记录每次请求的日志
下面就是一个符合规范的middleware, 构造函数中接受一个wsgi app, __call__返回一个wsgi app.
代码如下:
class loggermiddleware(object):
    '''wsgi middleware'''
    def __init__(self, application):
        self.app = application
    def __call__(self, environ, start_response):
        # write logs
        try:
            return self.app(environ, start_response)
        except exception, e:
            # write logs
            pass
        finally:
            # write logs
            pass
在项目的__init__.py的main函数中， 在config.make_wsgi_app上包上一层我们的middleware:
代码如下:
from pyramid.config import configurator
    config = configurator()
    config.scan()
    app = config.make_wsgi_app()
    # put middleware
    app = loggermiddleware(app)
    serve(app, host='0.0.0.0')