2 # ============LICENSE_START===============================================
3 # Copyright (C) 2020 Nordix Foundation. All rights reserved.
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
9 # http://www.apache.org/licenses/LICENSE-2.0
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 # ============LICENSE_END=================================================
19 from flask import Flask, request
20 from time import sleep
24 from flask import Flask
25 from flask import Response
30 # list of messages to/from Dmaap
39 cntr_msg_requests_submitted=0
40 cntr_msg_requests_fetched=0
41 cntr_msg_responses_submitted=0
42 cntr_msg_responses_fetched=0
44 # Request and response constants
45 AGENT_WRITE_URL="/events/A1-POLICY-AGENT-WRITE"
46 AGENT_READ_URL="/events/A1-POLICY-AGENT-READ/users/policy-agent"
47 APP_WRITE_URL="/send-request"
48 APP_READ_URL="/receive-response"
49 MIME_TEXT="text/plain"
50 MIME_JSON="application/json"
51 CAUGHT_EXCEPTION="Caught exception: "
52 SERVER_ERROR="Server error :"
61 # Helper function to create a Dmaap request message
62 # args : <GET|PUT|DELETE> <correlation-id> <json-string-payload - may be None> <url>
63 # response: json formatted string of a complete Dmaap message
64 def create_message(operation, correlation_id, payload, url):
67 time_stamp=datetime.datetime.utcnow()
68 msg = '{\"apiVersion\":\"1.0\",\"operation\":\"'+operation+'\",\"correlationId\":\"'+correlation_id+'\",\"originatorId\": \"849e6c6b420\",'
69 msg = msg + '\"payload\":'+payload+',\"requestId\":\"23343221\", \"target\":\"policy-agent\", \"timestamp\":\"'+str(time_stamp)+'\", \"type\":\"request\",\"url\":\"'+url+'\"}'
73 ### MR-stub interface, for MR control
75 # Send a message to MR
76 # URI and parameters (GET): /send-request?operation=<GET|PUT|POST|DELETE>&url=<url>
77 # response: <correlation-id> (http 200) o4 400 for parameter error or 500 for other errors
78 @app.route(APP_WRITE_URL,
79 methods=['PUT','POST'])
82 global cntr_msg_requests_submitted
86 oper=request.args.get('operation')
88 print(APP_WRITE_URL+" parameter 'operation' missing")
89 return Response('Parameter operation missing in request', status=400, mimetype=MIME_TEXT)
91 url=request.args.get('url')
93 print(APP_WRITE_URL+" parameter 'url' missing")
94 return Response('Parameter url missing in request', status=400, mimetype=MIME_TEXT)
96 if (oper != "GET" and oper != "PUT" and oper != "POST" and oper != "DELETE"):
97 print(APP_WRITE_URL+" parameter 'operation' need to be: DEL|PUT|POST|DELETE")
98 return Response('Parameter operation does not contain DEL|PUT|POST|DELETE in request', status=400, mimetype=MIME_TEXT)
100 print(APP_WRITE_URL+" operation="+oper+" url="+url)
101 correlation_id=str(time.time_ns())
103 if (oper == "PUT") and (request.json is not None):
104 payload=json.dumps(request.json)
106 msg=create_message(oper, correlation_id, payload, url)
108 print(APP_WRITE_URL+" MSG(correlationid = "+correlation_id+"): " + json.dumps(json.loads(msg), indent=2))
109 msg_requests.append(msg)
110 cntr_msg_requests_submitted += 1
111 return Response(correlation_id, status=200, mimetype=MIME_TEXT)
112 except Exception as e:
113 print(APP_WRITE_URL+"-"+CAUGHT_EXCEPTION+" "+str(e) + " "+traceback.format_exc())
114 return Response(SERVER_ERROR+" "+str(e), status=500, mimetype=MIME_TEXT)
116 # Receive a message response for MR for the included correlation id
117 # URI and parameter, (GET): /receive-response?correlationid=<correlation-id>
118 # response: <json-array of 1 response> 200 or empty 204 or other errors 500
119 @app.route(APP_READ_URL,
121 def receiveresponse():
123 global cntr_msg_responses_fetched
126 id=request.args.get('correlationid')
128 print(APP_READ_URL+" parameter 'correclationid' missing")
129 return Response('Parameter correlationid missing in json', status=500, mimetype=MIME_TEXT)
131 if (id in msg_responses):
132 answer=msg_responses[id]
133 del msg_responses[id]
134 print(APP_READ_URL+" response (correlationid="+id+"): " + answer)
135 cntr_msg_responses_fetched += 1
136 return Response(answer, status=200, mimetype=MIME_JSON)
138 print(APP_READ_URL+" - no messages (correlationid="+id+"): ")
139 return Response('', status=204, mimetype=MIME_JSON)
140 except Exception as e:
141 print(APP_READ_URL+"-"+CAUGHT_EXCEPTION+" "+str(e) + " "+traceback.format_exc())
142 return Response(SERVER_ERROR+" "+str(e), status=500, mimetype=MIME_TEXT)
144 ### Dmaap interface ###
146 # Read messages stream. URI according to agent configuration.
147 # URI, (GET): /events/A1-POLICY-AGENT-READ/users/policy-agent
148 # response: 200 <json array of request messages>, or 500 for other errors
149 @app.route(AGENT_READ_URL,
153 global cntr_msg_requests_fetched
155 limit=request.args.get('limit')
164 print("Limting number of returned messages to: "+str(limit))
168 while(cntr<limit and len(msg_requests)>0):
171 msgs=msgs+msg_requests.pop(0)
172 cntr_msg_requests_fetched += 1
175 print(AGENT_READ_URL+" MSGs: "+json.dumps(json.loads(msgs), indent=2))
176 return Response(msgs, status=200, mimetype=MIME_JSON)
177 except Exception as e:
178 print(AGENT_READ_URL+"-"+CAUGHT_EXCEPTION+" "+str(e) + " "+traceback.format_exc())
179 return Response(SERVER_ERROR+" "+str(e), status=500, mimetype=MIME_TEXT)
181 # Write messages stream. URI according to agent configuration.
182 # URI and payload, (PUT or POST): /events/A1-POLICY-AGENT-WRITE <json array of response messages>
183 # response: OK 200 or 400 for missing json parameters, 500 for other errors
184 @app.route(AGENT_WRITE_URL,
185 methods=['PUT','POST'])
188 global cntr_msg_responses_submitted
192 print(AGENT_WRITE_URL+ " json=" + json.dumps(answer, indent=2))
194 id=item['correlationId']
196 print(AGENT_WRITE_URL+" parameter 'correlatonid' missing")
197 return Response('Parameter <correlationid> missing in json', status=400, mimetype=MIME_TEXT)
200 print(AGENT_WRITE_URL+" parameter 'msgs' missing")
201 return Response('Parameter >message> missing in json', status=400, mimetype=MIME_TEXT)
202 status=item['status']
204 print(AGENT_WRITE_URL+" parameter 'status' missing")
205 return Response('Parameter <status> missing in json', status=400, mimetype=MIME_TEXT)
206 if isinstance(msg, list) or isinstance(msg, dict):
207 msg_str=json.dumps(msg)+status[0:3]
209 msg_str=msg+status[0:3]
210 msg_responses[id]=msg_str
211 cntr_msg_responses_submitted += 1
212 print(AGENT_WRITE_URL+ " msg+status (correlationid="+id+") :" + str(msg_str))
213 except Exception as e:
214 print(AGENT_WRITE_URL+"-"+CAUGHT_EXCEPTION+" "+str(e) + " "+traceback.format_exc())
215 return Response(SERVER_ERROR+" "+str(e), status=500, mimetype=MIME_TEXT)
217 return Response('OK', status=200, mimetype=MIME_TEXT)
220 ### Functions for metrics read out ###
222 @app.route('/counter/requests_submitted',
224 def requests_submitted():
225 return Response(str(cntr_msg_requests_submitted), status=200, mimetype=MIME_TEXT)
227 @app.route('/counter/requests_fetched',
229 def requests_fetched():
230 return Response(str(cntr_msg_requests_fetched), status=200, mimetype=MIME_TEXT)
232 @app.route('/counter/responses_submitted',
234 def responses_submitted():
235 return Response(str(cntr_msg_responses_submitted), status=200, mimetype=MIME_TEXT)
237 @app.route('/counter/responses_fetched',
239 def responses_fetched():
240 return Response(str(cntr_msg_responses_fetched), status=200, mimetype=MIME_TEXT)
242 @app.route('/counter/current_requests',
244 def current_requests():
245 return Response(str(len(msg_requests)), status=200, mimetype=MIME_TEXT)
247 @app.route('/counter/current_responses',
249 def current_responses():
250 return Response(str(len(msg_responses)), status=200, mimetype=MIME_TEXT)
254 # Reset all messsages and counters
256 methods=['GET', 'POST', 'PUT'])
258 global cntr_msg_requests_submitted
259 global cntr_msg_requests_fetched
260 global cntr_msg_responses_submitted
261 global cntr_msg_responses_fetched
265 cntr_msg_requests_submitted=0
266 cntr_msg_requests_fetched=0
267 cntr_msg_responses_submitted=0
268 cntr_msg_responses_fetched=0
271 return Response('OK', status=200, mimetype=MIME_TEXT)
273 ### Main function ###
275 if __name__ == "__main__":
276 app.run(port=HOST_PORT, host=HOST_IP)