简单介绍Python下自己编写web框架的一些要点

# 首页:
@get('/')
def index():
  return '<h1>Index page</h1>'

# 带参数的URL:
@get('/user/:id')
def show_user(id):
  user = User.get(id)
  return 'hello, %s' % user.name

@interceptor('/manage/')
def check_manage_url(next):
  if current_user.isAdmin():
    return next()
  else:
    raise seeother('/signin')

@view('index.html')
@get('/')
def index():
  return dict(blogs=get_recent_blogs(), user=get_current_user())

@get('/test')
def test():
  input_data = ctx.request.input()
  ctx.response.content_type = 'text/plain'
  ctx.response.set_cookie('name', 'value', expires=3600)
  return 'result'

raise seeother('/signin')

raise notfound()

# transwarp/web.py

# 全局ThreadLocal对象：
ctx = threading.local()

# HTTP错误类:
class HttpError(Exception):
  pass

# request对象:
class Request(object):
  # 根据key返回value:
  def get(self, key, default=None):
    pass

  # 返回key-value的dict:
  def input(self):
    pass

  # 返回URL的path:
  @property
  def path_info(self):
    pass

  # 返回HTTP Headers:
  @property
  def headers(self):
    pass

  # 根据key返回Cookie value:
  def cookie(self, name, default=None):
    pass

# response对象:
class Response(object):
  # 设置header:
  def set_header(self, key, value):
    pass

  # 设置Cookie:
  def set_cookie(self, name, value, max_age=None, expires=None, path='/'):
    pass

  # 设置status:
  @property
  def status(self):
    pass
  @status.setter
  def status(self, value):
    pass

# 定义GET:
def get(path):
  pass

# 定义POST:
def post(path):
  pass

# 定义模板:
def view(path):
  pass

# 定义拦截器:
def interceptor(pattern):
  pass

# 定义模板引擎:
class TemplateEngine(object):
  def __call__(self, path, model):
    pass

# 缺省使用jinja2:
class Jinja2TemplateEngine(TemplateEngine):
  def __init__(self, templ_dir, **kw):
    from jinja2 import Environment, FileSystemLoader
    self._env = Environment(loader=FileSystemLoader(templ_dir), **kw)

  def __call__(self, path, model):
    return self._env.get_template(path).render(**model).encode('utf-8')

wsgi = WSGIApplication()
if __name__ == '__main__':
  wsgi.run()
else:
  application = wsgi.get_wsgi_application()

因此，WSGIApplication定义如下：

class WSGIApplication(object):
  def __init__(self, document_root=None, **kw):
    pass

  # 添加一个URL定义:
  def add_url(self, func):
    pass

  # 添加一个Interceptor定义:
  def add_interceptor(self, func):
    pass

  # 设置TemplateEngine:
  @property
  def template_engine(self):
    pass

  @template_engine.setter
  def template_engine(self, engine):
    pass

  # 返回WSGI处理函数:
  def get_wsgi_application(self):
    def wsgi(env, start_response):
      pass
    return wsgi

  # 开发模式下直接启动服务器:
  def run(self, port=9000, host='127.0.0.1'):
    from wsgiref.simple_server import make_server
    server = make_server(host, port, self.get_wsgi_application())
    server.serve_forever()
Try