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我必须将参数传递给SimpleHTTPRequestHandler类,因此我使用类工厂创建了如下的自定义处理程序。将参数传递给SimpleHTTPRequestHandler

def RequestHandlerClass(application_path):  

    class CustomHandler(SimpleHTTPRequestHandler): 

    def __init__(self, request, client_address, server): 

     SimpleHTTPRequestHandler.__init__(self, request, client_address, server) 
     self._file_1_done = False 
     self._file_2_done = False 
     self._application_path = application_path 

    def _reset_flags(self): 

     self._file_1_done = False 
     self._file_2_done = False 

    def do_GET(self): 

     if (self.path == '/file1.qml'): 
      self._file_1_done = True 

     if (self.path == '/file2.qml'): 
      self._file_2_done = True 

     filepath = self._application_path + '/' + self.path # Error here 

     try: 
      f = open(filepath) 
      self.send_response(200) 
      self.end_headers() 
      self.wfile.write(f.read()) 
      f.close() 
     except IOError as e : 
      self.send_error(404,'File Not Found: %s' % self.path)  


     if (self._file_1_done and self._file_2_done): 
      self._reset_flags() 
      self.server.app_download_complete_event.set() 
    return CustomHandler 

这是使用自定义的处理

class PythonHtpServer(BaseHTTPServer.HTTPServer, threading.Thread): 

    def __init__(self, port, serve_path): 
    custom_request_handler_class = RequestHandlerClass(serve_path) 
    BaseHTTPServer.HTTPServer.__init__(self, ('0.0.0.0', port), custom_request_handler_class) 
    threading.Thread.__init__(self) 
    self.app_download_complete_event = threading.Event() 

    def run(self): 
    self.serve_forever() 

    def stop(self): 
    self.shutdown()  

我的httpserver,我开始与

http_server = PythonHtpServer(port = 8123, serve_path = '/application/main.qml') 

服务器启动服务器,但我得到这个错误

AttributeError: CustomHandler instance has no attribute '_application_path' 

基本上,从错误,服务器确实开始,但我不知道为什么它不创建属性(或者init没有被调用)。请告诉我我哪里错了。任何帮助将受到欢迎。

回答

0

从概念上讲,你写这样的事情(在此例如,application_path〜= var):

def createClass(var): 
    class MyClass: 
     def __init__(self): 
      self.var = var 
     def func(self): 
      # use var in some way 
      print (self.var) 
    # Return class definition 
    return MyClass 

因此类被写入到保存变量var当创建MyClass实例。然而,在函数结束时,变量被破坏,由于该类只返回一个类定义而不是类实例MyClass实例不会获得由当时的原始变量创建var被销毁,因此变量var从来没有真正被MyClass保存。

相反,你可以添加var作为参数传递给MyClass.__init__功能,并创建一个生成器类来处理MyClass实例的创建,像这样:

class MyClass: 
    def __init__(self, arg1, arg2, var): 
     (self.arg1, self.arg2, self.var) = (arg1, arg2, var) 
    # Insert other methods as usual 

class MyClassGenerator: 
    def __init__(self, var): 
     self.var = var 
    def make(self, arg1, arg2): 
     return MyClass(arg1, arg2, var) 
2

恕我直言,最简单的方法就是让_application_path静态类的属性。它仅在类声明时申报,并可以通过类的实例透明地使用:

def RequestHandlerClass(application_path):  

    class CustomHandler(SimpleHTTPRequestHandler): 

    _application_path = application_path # static attribute 

    def __init__(self, request, client_address, server): 

     SimpleHTTPRequestHandler.__init__(self, request, client_address, server) 
     self._file_1_done = False 
     self._file_2_done = False 

    def _reset_flags(self): 
     ... 

这样的自定义处理程序类的每个新实例将有机会获得为self._application_path应用程序的路径。