Question

这让我感到困惑了一段时间。我正在尝试创建一个非常简单的类似REST的接口（不使用第三方库，我知道这些库可用）。

它背后的想法是我可以有一个目录，例如mylib，我可以在其中放入python文件，如do_something.py，并通过POST到http://localhost/do_something代码将进入生活并做点什么！

我想我已经设法通过以下结构到达我的目标附近：

文件内容如下。

example.py
from http.server import HTTPServer
from http.server import BaseHTTPRequestHandler
import json, logging
from mylib import my_module

class MyRequestHandler (BaseHTTPRequestHandler):

    # Send JSON responses
    # -----------
    def send_json(self, json_message, response_code=200):
        self.send_response(response_code)
        self.send_header('Content-type', 'application/json')
        self.end_headers()
        self.request.sendall(json.dumps(json_message).encode())


    # Get JSON requests
    # ----------
    def get_json(self):
        body = self.rfile.read(int(self.headers.get('Content-Length')))
        if (body):
            try:
                receivedData = json.loads(body.decode())
            except:
                self.send_json({"Status": "Error", "Message": "Invalid JSON received"}, 400)
                receivedData = None
        else:
            receivedData = None
        return receivedData


    # POST
    # ---------
    def do_POST(self):

        module_to_call = (self.path).replace('/', '.')[1:]
        if module_to_call.endswith('.'): # Remove trailing dot
            module_to_call = module_to_call[:-1]
        print("Path is: '" + module_to_call + "'")

        # invoke function
        module_to_call = getattr(self, module_to_call)
        response = module_to_call()
        self.send_json(response)

    # GET
    # --------
    def do_GET(self):

        pass


# -----------------------------------------------------------------------------
# Server startup code
# -------------------
def start_server():


# Begin serving
# -------------
    port = 8003
    server = HTTPServer(('', port), MyRequestHandler)
    print(("Server now running on port {0} ...").format(port))

    server.serve_forever()


# -----------------------------------------------------------------------------
# Start the Server
# ----------------
if __name__ == '__main__':
    start_server()

my_module.py

def my_module():
    print("Hello World!")
    return{'Greeting': 'Hello World!'}

当我启动服务器并尝试POST到http://localhost:8003/my_module时，我得到以下输出：

Server now running on port 8003 ...
Path is: 'my_module'
----------------------------------------
Exception happened during processing of request from ('127.0.0.1', 59541)
Traceback (most recent call last):
  File "C:\Users\Test\AppData\Local\Programs\Python\Python35-32\lib\socketserver.py", line 313, in _handle_request_noblock
    self.process_request(request, client_address)
  File "C:\Users\Test\AppData\Local\Programs\Python\Python35-32\lib\socketserver.py", line 341, in process_request
    self.finish_request(request, client_address)
  File "C:\Users\Test\AppData\Local\Programs\Python\Python35-32\lib\socketserver.py", line 354, in finish_request
    self.RequestHandlerClass(request, client_address, self)
  File "C:\Users\Test\AppData\Local\Programs\Python\Python35-32\lib\socketserver.py", line 681, in __init__
    self.handle()
  File "C:\Users\Test\AppData\Local\Programs\Python\Python35-32\lib\http\server.py", line 422, in handle
    self.handle_one_request()
  File "C:\Users\Test\AppData\Local\Programs\Python\Python35-32\lib\http\server.py", line 410, in handle_one_request
    method()
  File ".\example.py", line 43, in do_POST
    module_to_call = getattr(self, module_to_call)
AttributeError: 'MyRequestHandler' object has no attribute 'my_module'
----------------------------------------

这很有道理，因为＆＃39; MyRequestHandler＆＃34;没有属性＆＃34; my_module＆＃34;！我无法解决的问题是如何解决这个问题？

我应该通过＆＃34; mylib＆＃34;进入MyRequestHandler？我应该在类中执行导入（但是该功能只能在类中使用）？

我试图保持简洁，所以即使是Python新手（就像我好像！）也可以写一个独立的脚本，将其放入＆＃34; mylib＆＃34;和一切＆＃34;只是工作＆＃34;。新手可以访问他们脚本的网址，让它神奇地运行。

感谢任何帮助或建议。

Answer 1

使用__import__()方法：

temp = __import__('mylib', globals(), locals(), ['module_to_call'], -1)
response = temp.module_to_call()

我在工作中使用2.6，这通常被那些使用2.7的人使用，因为importlib模块在3中更强大。如果你使用3，你可以执行以下操作：

from importlib import import_module

temp = import_module('mylib')

但现在你必须使用getattr来获得你想要调用的函数

func_to_call = getattr(temp, 'module_to_call')
response = func()

或者您可以在另一个模块中使用函数字典，但随着字典的增长，这将需要大量的工作。

Python - Access＆＃34; import＆＃34;来自班级

1 个答案: