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
27 from threading import RLock
31 # list of messages to/from Dmaap
40 cntr_msg_requests_submitted=0
41 cntr_msg_requests_fetched=0
42 cntr_msg_responses_submitted=0
43 cntr_msg_responses_fetched=0
45 # Request and response constants
46 AGENT_WRITE_URL="/events/A1-POLICY-AGENT-WRITE"
47 AGENT_READ_URL="/events/A1-POLICY-AGENT-READ/users/policy-agent"
48 APP_WRITE_URL="/send-request"
49 APP_READ_URL="/receive-response"
50 MIME_TEXT="text/plain"
51 MIME_JSON="application/json"
52 CAUGHT_EXCEPTION="Caught exception: "
53 SERVER_ERROR="Server error :"
62 # Helper function to create a Dmaap request message
63 # args : <GET|PUT|DELETE> <correlation-id> <json-string-payload - may be None> <url>
64 # response: json formatted string of a complete Dmaap message
65 def create_message(operation, correlation_id, payload, url):
68 time_stamp=datetime.datetime.utcnow()
69 msg = '{\"apiVersion\":\"1.0\",\"operation\":\"'+operation+'\",\"correlationId\":\"'+correlation_id+'\",\"originatorId\": \"849e6c6b420\",'
70 msg = msg + '\"payload\":'+payload+',\"requestId\":\"23343221\", \"target\":\"policy-agent\", \"timestamp\":\"'+str(time_stamp)+'\", \"type\":\"request\",\"url\":\"'+url+'\"}'
74 ### MR-stub interface, for MR control
76 # Send a message to MR
77 # URI and parameters (GET): /send-request?operation=<GET|PUT|POST|DELETE>&url=<url>
78 # response: <correlation-id> (http 200) o4 400 for parameter error or 500 for other errors
79 @app.route(APP_WRITE_URL,
80 methods=['PUT','POST'])
83 global cntr_msg_requests_submitted
85 print("APP_WRITE_URL lock")
87 oper=request.args.get('operation')
89 print(APP_WRITE_URL+" parameter 'operation' missing")
90 return Response('Parameter operation missing in request', status=400, mimetype=MIME_TEXT)
92 url=request.args.get('url')
94 print(APP_WRITE_URL+" parameter 'url' missing")
95 return Response('Parameter url missing in request', status=400, mimetype=MIME_TEXT)
97 if (oper != "GET" and oper != "PUT" and oper != "POST" and oper != "DELETE"):
98 print(APP_WRITE_URL+" parameter 'operation' need to be: DEL|PUT|POST|DELETE")
99 return Response('Parameter operation does not contain DEL|PUT|POST|DELETE in request', status=400, mimetype=MIME_TEXT)
101 print(APP_WRITE_URL+" operation="+oper+" url="+url)
102 correlation_id=str(time.time_ns())
104 if (oper == "PUT") and (request.json is not None):
105 payload=json.dumps(request.json)
107 msg=create_message(oper, correlation_id, payload, url)
109 print(APP_WRITE_URL+" MSG(correlationid = "+correlation_id+"): " + json.dumps(json.loads(msg), indent=2))
110 msg_requests.append(msg)
111 cntr_msg_requests_submitted += 1
112 return Response(correlation_id, status=200, mimetype=MIME_TEXT)
113 except Exception as e:
114 print(APP_WRITE_URL+"-"+CAUGHT_EXCEPTION+" "+str(e) + " "+traceback.format_exc())
115 return Response(SERVER_ERROR+" "+str(e), status=500, mimetype=MIME_TEXT)
117 # Receive a message response for MR for the included correlation id
118 # URI and parameter, (GET): /receive-response?correlationid=<correlation-id>
119 # response: <json-array of 1 response> 200 or empty 204 or other errors 500
120 @app.route(APP_READ_URL,
122 def receiveresponse():
124 global cntr_msg_responses_fetched
126 print("APP_READ_URL lock")
128 id=request.args.get('correlationid')
130 print(APP_READ_URL+" parameter 'correclationid' missing")
131 return Response('Parameter correlationid missing in json', status=500, mimetype=MIME_TEXT)
133 if (id in msg_responses):
134 answer=msg_responses[id]
135 del msg_responses[id]
136 print(APP_READ_URL+" response (correlationid="+id+"): " + answer)
137 cntr_msg_responses_fetched += 1
138 return Response(answer, status=200, mimetype=MIME_JSON)
140 print(APP_READ_URL+" - no messages (correlationid="+id+"): ")
141 return Response('', status=204, mimetype=MIME_JSON)
142 except Exception as e:
143 print(APP_READ_URL+"-"+CAUGHT_EXCEPTION+" "+str(e) + " "+traceback.format_exc())
144 return Response(SERVER_ERROR+" "+str(e), status=500, mimetype=MIME_TEXT)
146 ### Dmaap interface ###
148 # Read messages stream. URI according to agent configuration.
149 # URI, (GET): /events/A1-POLICY-AGENT-READ/users/policy-agent
150 # response: 200 <json array of request messages>, or 500 for other errors
151 @app.route(AGENT_READ_URL,
155 global cntr_msg_requests_fetched
157 limit=request.args.get('limit')
166 print("Limting number of returned messages to: "+str(limit))
168 timeout=request.args.get('timeout')
169 if (timeout is None):
172 timeout=min(int(timeout),60000)
174 startTime=int(round(time.time() * 1000))
175 currentTime=int(round(time.time() * 1000))
177 while(currentTime<startTime+int(timeout)):
179 if(len(msg_requests)>0):
183 while(cntr<limit and len(msg_requests)>0):
186 msgs=msgs+msg_requests.pop(0)
187 cntr_msg_requests_fetched += 1
190 print(AGENT_READ_URL+" MSGs: "+json.dumps(json.loads(msgs), indent=2))
191 return Response(msgs, status=200, mimetype=MIME_JSON)
192 except Exception as e:
193 print(AGENT_READ_URL+"-"+CAUGHT_EXCEPTION+" "+str(e) + " "+traceback.format_exc())
194 return Response(SERVER_ERROR+" "+str(e), status=500, mimetype=MIME_TEXT)
195 sleep(0.025) # sleep 25 milliseconds
196 currentTime=int(round(time.time() * 1000))
198 print("timeout: "+str(timeout)+", startTime: "+str(startTime)+", currentTime: "+str(currentTime))
199 return Response("[]", status=200, mimetype=MIME_JSON)
201 # Write messages stream. URI according to agent configuration.
202 # URI and payload, (PUT or POST): /events/A1-POLICY-AGENT-WRITE <json array of response messages>
203 # response: OK 200 or 400 for missing json parameters, 500 for other errors
204 @app.route(AGENT_WRITE_URL,
205 methods=['PUT','POST'])
208 global cntr_msg_responses_submitted
210 print("AGENT_WRITE_URL lock")
213 print(AGENT_WRITE_URL+ " json=" + json.dumps(answer, indent=2))
214 if isinstance(answer, dict):
215 #Create a an array if the answer is a dict (single message)
217 answer_list.append(answer)
221 id=item['correlationId']
223 print(AGENT_WRITE_URL+" parameter 'correlatonid' missing")
224 return Response('Parameter <correlationid> missing in json', status=400, mimetype=MIME_TEXT)
227 print(AGENT_WRITE_URL+" parameter 'msgs' missing")
228 return Response('Parameter >message> missing in json', status=400, mimetype=MIME_TEXT)
229 status=item['status']
231 print(AGENT_WRITE_URL+" parameter 'status' missing")
232 return Response('Parameter <status> missing in json', status=400, mimetype=MIME_TEXT)
233 if isinstance(msg, list) or isinstance(msg, dict):
234 msg_str=json.dumps(msg)+status[0:3]
236 msg_str=msg+status[0:3]
237 msg_responses[id]=msg_str
238 cntr_msg_responses_submitted += 1
239 print(AGENT_WRITE_URL+ " msg+status (correlationid="+id+") :" + str(msg_str))
240 except Exception as e:
241 print(AGENT_WRITE_URL+"-"+CAUGHT_EXCEPTION+" "+str(e) + " "+traceback.format_exc())
242 return Response('{"message": "' + SERVER_ERROR + ' ' + str(e) + '","status":"500"}', status=200, mimetype=MIME_JSON)
244 return Response('{}', status=200, mimetype=MIME_JSON)
247 ### Functions for metrics read out ###
249 @app.route('/counter/requests_submitted',
251 def requests_submitted():
252 return Response(str(cntr_msg_requests_submitted), status=200, mimetype=MIME_TEXT)
254 @app.route('/counter/requests_fetched',
256 def requests_fetched():
257 return Response(str(cntr_msg_requests_fetched), status=200, mimetype=MIME_TEXT)
259 @app.route('/counter/responses_submitted',
261 def responses_submitted():
262 return Response(str(cntr_msg_responses_submitted), status=200, mimetype=MIME_TEXT)
264 @app.route('/counter/responses_fetched',
266 def responses_fetched():
267 return Response(str(cntr_msg_responses_fetched), status=200, mimetype=MIME_TEXT)
269 @app.route('/counter/current_requests',
271 def current_requests():
272 return Response(str(len(msg_requests)), status=200, mimetype=MIME_TEXT)
274 @app.route('/counter/current_responses',
276 def current_responses():
277 return Response(str(len(msg_responses)), status=200, mimetype=MIME_TEXT)
281 # Reset all messsages and counters
283 methods=['GET', 'POST', 'PUT'])
285 global cntr_msg_requests_submitted
286 global cntr_msg_requests_fetched
287 global cntr_msg_responses_submitted
288 global cntr_msg_responses_fetched
292 cntr_msg_requests_submitted=0
293 cntr_msg_requests_fetched=0
294 cntr_msg_responses_submitted=0
295 cntr_msg_responses_fetched=0
298 return Response('OK', status=200, mimetype=MIME_TEXT)
300 if __name__ == "__main__":
301 app.run(port=HOST_PORT, host=HOST_IP)