简单实现 web/app端 经API GateWay 将请求转发至微服务，并将数据返回给client客户端。
环境：Windows10，Linux虚拟机，postman，Python3.7
postman是在本地Windows系统上请求，API GateWay代码是运行在本地window上的，一个简单的微服务在Linux上运行。
详情见下：
1、API GateWay 部分代码：
# server.py
# 从wsgiref模块导入:
from wsgiref.simple_server import make_server
# 导入我们自己编写的application函数:
from hello import application
# 创建一个服务器，IP地址为空，端口是8000，处理函数是application:
httpd = make_server(\'\', 8000, application)
print(\'Serving HTTP on port 8000...\')
# 开始监听HTTP请求:
httpd.serve_forever()
# hello.py
import json
import requests
def application(environ, start_response):
start_response(\'200 OK\', [(\'Content-Type\', \'application/json\')])
# start_response(\'200 OK\', [(\'Content-Type\', \'text/html\')])
# return [b\'<h1>Hello, web!</h1>\']
print(environ[\'PATH_INFO\'])
url = environ[\'PATH_INFO\'] # web客户端请求 API网关的 url
params = {
"name": "john",
"age": 16,
"address": "地址",
"salary": "200"
}
resp = req(url, params=params)
print(\'真实服务器返回给api网关的内容：\', resp, type(resp))
return [json.dumps(resp)]
# return [b"{\'a\': 1, \'b\': 2}"]
# 模拟请求真实的服务
def req(url, params=None):
response = requests.post(\'http://192.168.175.134:6666\' + url, json=params)
return response.json()
2、微服务代码：
3、web/APP端请求，通过postman模拟：
测试过程中遇到的错误：
C:\\Users\\XH\\Anaconda3\\python.exe D:/dev/dev_py/library/api_gateway_server/server.py
Serving HTTP on port 8000...
/api/ssss
真实服务器返回给api网关的内容： {\'a\': 1, \'b\': 2} <class \'dict\'>
127.0.0.1 - - [24/Apr/2020 19:18:41] "POST /api/ssss HTTP/1.1" 200 0
Traceback (most recent call last):
File "C:\\Users\\XH\\Anaconda3\\lib\\wsgiref\\handlers.py", line 138, in run
self.finish_response()
File "C:\\Users\\XH\\Anaconda3\\lib\\wsgiref\\handlers.py", line 181, in finish_response
self.write(data)
File "C:\\Users\\XH\\Anaconda3\\lib\\wsgiref\\handlers.py", line 267, in write
"write() argument must be a bytes instance"
AssertionError: write() argument must be a bytes instance
127.0.0.1 - - [24/Apr/2020 19:18:41] "POST /api/ssss HTTP/1.1" 500 59
----------------------------------------
Exception happened during processing of request from (\'127.0.0.1\', 55306)
Traceback (most recent call last):
File "C:\\Users\\XH\\Anaconda3\\lib\\wsgiref\\handlers.py", line 138, in run
self.finish_response()
File "C:\\Users\\XH\\Anaconda3\\lib\\wsgiref\\handlers.py", line 181, in finish_response
self.write(data)
File "C:\\Users\\XH\\Anaconda3\\lib\\wsgiref\\handlers.py", line 267, in write
"write() argument must be a bytes instance"
AssertionError: write() argument must be a bytes instance
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "C:\\Users\\XH\\Anaconda3\\lib\\wsgiref\\handlers.py", line 141, in run
self.handle_error()
File "C:\\Users\\XH\\Anaconda3\\lib\\wsgiref\\handlers.py", line 369, in handle_error
self.finish_response()
File "C:\\Users\\XH\\Anaconda3\\lib\\wsgiref\\handlers.py", line 181, in finish_response
self.write(data)
File "C:\\Users\\XH\\Anaconda3\\lib\\wsgiref\\handlers.py", line 275, in write
self.send_headers()
File "C:\\Users\\XH\\Anaconda3\\lib\\wsgiref\\handlers.py", line 332, in send_headers
if not self.origin_server or self.client_is_modern():
File "C:\\Users\\XH\\Anaconda3\\lib\\wsgiref\\handlers.py", line 345, in client_is_modern
return self.environ[\'SERVER_PROTOCOL\'].upper() != \'HTTP/0.9\'
TypeError: \'NoneType\' object is not subscriptable
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "C:\\Users\\XH\\Anaconda3\\lib\\socketserver.py", line 313, in _handle_request_noblock
self.process_request(request, client_address)
File "C:\\Users\\XH\\Anaconda3\\lib\\socketserver.py", line 344, in process_request
self.finish_request(request, client_address)
File "C:\\Users\\XH\\Anaconda3\\lib\\socketserver.py", line 357, in finish_request
self.RequestHandlerClass(request, client_address, self)
File "C:\\Users\\XH\\Anaconda3\\lib\\socketserver.py", line 717, in __init__
self.handle()
File "C:\\Users\\XH\\Anaconda3\\lib\\wsgiref\\simple_server.py", line 133, in handle
handler.run(self.server.get_app())
File "C:\\Users\\XH\\Anaconda3\\lib\\wsgiref\\handlers.py", line 144, in run
self.close()
File "C:\\Users\\XH\\Anaconda3\\lib\\wsgiref\\simple_server.py", line 35, in close
self.status.split(\' \',1)[0], self.bytes_sent
AttributeError: \'NoneType\' object has no attribute \'split\'
----------------------------------------
解决：
经测试，路子可以走通。
以上。
参考：廖雪峰的WSGI接口，博客园二流子的python3.4中自定义wsgi函数，make_server函数报错问题。