簡單實現 web/app端 經API GateWay 將請求轉發至微服務，並將數據返回給client客戶端。
環境：Windows10，Linux虛擬機，postman，Python3.7
postman是在本地Windows系統上請求，API GateWay代碼是運行在本地window上的，一個簡單的微服務在Linux上運行。
詳情見下：
1、API GateWay 部分代碼：
# server.py
# 從wsgiref模塊導入:
from wsgiref.simple_server import make_server
# 導入我們自己編寫的application函數:
from hello import application
# 創建一個服務器，IP地址為空，端口是8000，處理函數是application:
httpd = make_server('', 8000, application)
print('Serving HTTP on port 8000...')
# 開始監聽HTTP請求:
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客戶端請求 API網關的 url
params = {
"name": "john",
"age": 16,
"address": "地址",
"salary": "200"
}
resp = req(url, params=params)
print('真實服務器返回給api網關的內容：', resp, type(resp))
return [json.dumps(resp)]
# return [b"{'a': 1, 'b': 2}"]
# 模擬請求真實的服務
def req(url, params=None):
response = requests.post('http://192.168.175.134:6666' + url, json=params)
return response.json()
2、微服務代碼：
3、web/APP端請求，通過postman模擬：
測試過程中遇到的錯誤：
C:\Users\XH\Anaconda3\python.exe D:/dev/dev_py/library/api_gateway_server/server.py
Serving HTTP on port 8000...
/api/ssss
真實服務器返回給api網關的內容： {'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'
----------------------------------------
解決：
經測試，路子可以走通。
以上。
參考：廖雪峰的WSGI接口，博客園二流子的python3.4中自定義wsgi函數，make_server函數報錯問題。