ricxappframe/xapp_rest.py

   1 #!/usr/bin/env python3
   2 # ==================================================================================
   3 #       Copyright (c) 2022 Nokia
   4 #
   5 #   Licensed under the Apache License, Version 2.0 (the "License");
   6 #   you may not use this file except in compliance with the License.
   7 #   You may obtain a copy of the License at
   8 #
   9 #          http://www.apache.org/licenses/LICENSE-2.0
  10 #
  11 #   Unless required by applicable law or agreed to in writing, software
  12 #   distributed under the License is distributed on an "AS IS" BASIS,
  13 #   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14 #   See the License for the specific language governing permissions and
  15 #   limitations under the License.
  16 # ==================================================================================
  17 import socket
  18 import http.server
  19 import threading
  20
  21
  22 def initResponse(status=200, response="OK"):
  23
  24     """
  25     initResponse
  26         init the reponse data for handler to get all details defined
  27
  28     Parameters
  29     ----------
  30     status: int
  31         http status code
  32     response: string
  33         http response text
  34     Returns
  35     -------
  36     response - http response text
  37     status - http status code
  38     payload - payload data for the client (response data text or attachment file data)
  39     attachment - file name of the attached payload data
  40     mode text (utf-8) or binary data
  41     """
  42     return {'response': response, 'status': status, 'payload': None, 'ctype': 'application/json', 'attachment': None, 'mode': 'plain'}
  43
  44
  45 class RestHandler(http.server.BaseHTTPRequestHandler):
  46
  47     def _findUrihandler(self, uri, keys):
  48         for key in keys:
  49             value = keys[key]
  50             if uri.find(value['uri']) >= 0:
  51                 return key, value
  52         return None, None
  53
  54     def _sendResponse(self, response):
  55         # sends the reponse according to the initResponse() response data
  56         self.send_response(response['status'])
  57         self.send_header("Server-name", "XAPP REST SERVER 0.9")
  58         self.send_header('Content-type', response['ctype'])
  59
  60         if response['payload'] is not None:
  61             # payload has been set
  62             length = len(response['payload'])
  63             if length != 0:
  64                 self.send_header('Content-length', length)
  65             if response['attachment'] is not None:
  66                 self.send_header('Content-Disposition', "attachment; filename=" + response['attachment'])
  67         self.end_headers()
  68         if response['payload'] is not None:
  69             if response['mode'] == 'plain':
  70                 # ascii mode
  71                 self.wfile.write(response['payload'].encode('utf-8'))
  72             elif response['mode'] == 'binary':
  73                 # binary mode
  74                 self.wfile.write(response['payload'])
  75
  76     def add_handler(self, method=None, name=None, uri=None, callback=None):
  77         """
  78         Adds the function handler for given uri. The function callback is matched in first matching
  79         uri. So prepare your handlers setup in such a way that those won't override each other. For example you can setup
  80         usual xapp handler in this list:
  81
  82             server = ricrest.ThreadedHTTPServer(address, port)
  83             server.handler.add_handler(self.server.handler, "GET", "config", "/ric/v1/config", self.configGetHandler)
  84             server.handler.add_handler(self.server.handler, "GET", "healthAlive", "/ric/v1/health/alive", self.healthyGetAliveHandler)
  85             server.handler.add_handler(self.server.handler, "GET", "healthReady", "/ric/v1/health/ready", self.healthyGetReadyHandler)
  86             server.handler.add_handler(self.server.handler, "GET", "symptomdata", "/ric/v1/symptomdata", self.symptomdataGetHandler)
  87
  88         Parameters
  89         ----------
  90         method string
  91             http method GET, POST, DELETE
  92         name string
  93             unique name - used for map name
  94         uri string
  95             http uri part which triggers the callback function
  96         cb  function
  97             function to be used for http method processing
  98         """
  99         if not hasattr(self, 'handlers'):
 100             # init method can't be used becuase it has been inherited from base object
 101             # so check the handlers existence and create if not defined
 102             self.lock = threading.Lock()
 103             self.handlers = dict()
 104             self.handlers["get"] = dict()
 105             self.handlers["post"] = dict()
 106             self.handlers["delete"] = dict()
 107         self.lock.acquire()
 108         if method == "GET":
 109             self.handlers["get"][name] = dict()
 110             self.handlers["get"][name]['uri'] = uri
 111             self.handlers["get"][name]['cb'] = callback
 112         elif method == "POST":
 113             self.handlers["post"][name] = dict()
 114             self.handlers["post"][name]['uri'] = uri
 115             self.handlers["post"][name]['cb'] = callback
 116         elif method == "DELETE":
 117             self.handlers["delete"][name] = dict()
 118             self.handlers["delete"][name]['uri'] = uri
 119             self.handlers["delete"][name]['cb'] = callback
 120         self.lock.release()
 121
 122     def do_GET(self):
 123         try:
 124             response = initResponse(status=404, response='Not Found')
 125             cbname, hndl = self._findUrihandler(self.path, self.handlers['get'])
 126             if hndl is not None:
 127                 # call the defined callback handler
 128                 response = hndl['cb'](cbname, self.path, None, self.headers['Content-Type'])
 129             self._sendResponse(response)
 130
 131         except (socket.error, IOError):
 132             pass
 133
 134     def do_DELETE(self):
 135         try:
 136             response = initResponse(status=404, response='Not Found')
 137             cbname, hndl = self._findUrihandler(self.path, self.handlers['delete'])
 138             if hndl is not None:
 139                 # call the defined callback handler
 140                 response = hndl['cb'](cbname, self.path, None, self.headers['Content-Type'])
 141             self._sendResponse(response)
 142         except (socket.error, IOError):
 143             pass
 144
 145     def do_POST(self):
 146         try:
 147             response = initResponse(status=404, response='Not Found')
 148             cbname, hndl = self._findUrihandler(self.path, self.handlers['post'])
 149             if hndl is not None:
 150                 data = self.rfile.read(int(self.headers['Content-Length']))
 151                 # call the defined callback handler
 152                 response = hndl['cb'](cbname, self.path, data, self.headers['Content-Type'])
 153                 print(response)
 154             self._sendResponse(response)
 155         except (socket.error, IOError):
 156             pass
 157
 158
 159 class ThreadedHTTPServer(object):
 160
 161     handler = RestHandler
 162     server_class = http.server.HTTPServer
 163
 164     def __init__(self, host, port):
 165         """
 166         init
 167
 168         Parameters
 169         ----------
 170         host string
 171             http listen interface ip ("0.0.0.0" binds all interfaces)
 172         port int
 173             listen service port
 174         """
 175         self.server = self.server_class((host, port), self.handler)
 176         self.server_thread = threading.Thread(target=self.server.serve_forever)
 177         self.server_thread.daemon = True
 178
 179     def start(self):
 180         """
 181         start
 182             starts the thread serving http requests
 183         """
 184         self.server_thread.start()
 185
 186     def stop(self):
 187         """
 188         stop
 189             stops thread serving http requests
 190         """
 191         self.server.socket.close()
 192         self.server.server_close()
 193         self.server.shutdown()