Illyoung Choi | a9d2c2c | 2019-07-12 13:29:42 -0700 | [diff] [blame] | 1 | #!/usr/bin/env python3 |
| 2 | |
| 3 | # Copyright 2019-present Open Networking Foundation |
| 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 | """ |
| 18 | Workflow Run |
| 19 | |
| 20 | This module implements Workflow Run interface |
| 21 | """ |
| 22 | |
| 23 | import json |
| 24 | import socketio |
| 25 | |
| 26 | from .countdown_latch import CountDownLatch |
| 27 | from .utils import get_noop_logger, gen_id, gen_seq_id |
| 28 | from .errors import ClientRPCError, ClientInputError, ClientResponseError |
| 29 | |
| 30 | WAIT_TIMEOUT = 10 # 10 seconds |
| 31 | |
| 32 | GREETING = 'cord.workflow.ctlsvc.greeting' |
Illyoung Choi | a9d2c2c | 2019-07-12 13:29:42 -0700 | [diff] [blame] | 33 | WORKFLOW_RUN_COUNT_EVENTS = 'cord.workflow.ctlsvc.workflow.run.count' |
| 34 | WORKFLOW_RUN_FETCH_EVENT = 'cord.workflow.ctlsvc.workflow.run.fetch' |
| 35 | WORKFLOW_RUN_NOTIFY_EVENT = 'cord.workflow.ctlsvc.workflow.run.notify' |
| 36 | |
| 37 | |
| 38 | class WorkflowRun(object): |
| 39 | def __init__(self, workflow_id, workflow_run_id, logger=None, name=None): |
| 40 | self.sio = socketio.Client() |
| 41 | self.workflow_id = workflow_id |
| 42 | self.workflow_run_id = workflow_run_id |
| 43 | |
| 44 | if logger: |
| 45 | self.logger = logger |
| 46 | else: |
| 47 | self.logger = get_noop_logger() |
| 48 | |
| 49 | if name: |
| 50 | self.name = name |
| 51 | else: |
| 52 | self.name = 'workflow_run_%s' % gen_id() |
| 53 | |
| 54 | self.req_id = gen_seq_id() |
| 55 | |
| 56 | # set sio handlers |
| 57 | self.logger.debug('Setting event handlers to Socket.IO') |
| 58 | self.sio.on('connect', self.__on_sio_connect) |
| 59 | self.sio.on('disconnect', self.__on_sio_disconnect) |
| 60 | self.sio.on(GREETING, self.__on_greeting_message) |
Illyoung Choi | a9d2c2c | 2019-07-12 13:29:42 -0700 | [diff] [blame] | 61 | self.sio.on(WORKFLOW_RUN_COUNT_EVENTS, self.__on_count_events_message) |
| 62 | self.sio.on(WORKFLOW_RUN_FETCH_EVENT, self.__on_fetch_event_message) |
| 63 | self.sio.on(WORKFLOW_RUN_NOTIFY_EVENT, self.__on_notify_event_message) |
| 64 | |
| 65 | self.handlers = { |
| 66 | 'connect': self.__noop_connect_handler, |
| 67 | 'disconnect': self.__noop_disconnect_handler, |
| 68 | 'notify': self.__noop_notify_handler |
| 69 | } |
| 70 | |
| 71 | # key is req_id |
| 72 | self.pending_requests = {} |
| 73 | |
| 74 | def set_logger(self, logger): |
| 75 | self.logger = logger |
| 76 | |
| 77 | def get_logger(self): |
| 78 | return self.logger |
| 79 | |
| 80 | def __on_sio_connect(self): |
| 81 | self.logger.debug('connected to the server') |
| 82 | handler = self.handlers['connect'] |
| 83 | if callable(handler): |
| 84 | handler() |
| 85 | |
| 86 | def __noop_connect_handler(self): |
| 87 | self.logger.debug('no-op connect handler') |
| 88 | |
| 89 | def __on_sio_disconnect(self): |
| 90 | self.logger.debug('disconnected from the server') |
| 91 | handler = self.handlers['disconnect'] |
| 92 | if callable(handler): |
| 93 | handler() |
| 94 | |
| 95 | def __noop_disconnect_handler(self): |
| 96 | self.logger.debug('no-op disconnect handler') |
| 97 | |
| 98 | def __noop_notify_handler(self, workflow_id, workflow_run_id, topic): |
| 99 | self.logger.debug('no-op notify handler') |
| 100 | |
| 101 | def __get_next_req_id(self): |
| 102 | req_id = self.req_id |
| 103 | self.req_id += 1 |
| 104 | return req_id |
| 105 | |
| 106 | def __on_greeting_message(self, data): |
Illyoung Choi | 67e54e7 | 2019-07-25 10:44:59 -0700 | [diff] [blame] | 107 | self.logger.debug('received a greeting message from the server') |
Illyoung Choi | a9d2c2c | 2019-07-12 13:29:42 -0700 | [diff] [blame] | 108 | |
| 109 | def __on_notify_event_message(self, data): |
| 110 | """ |
| 111 | Handler for a notify event |
| 112 | REQ = { |
| 113 | 'topic': <topic> |
| 114 | } |
| 115 | """ |
| 116 | self.logger.info('received a notify event message from the server') |
| 117 | topic = data['topic'] |
| 118 | |
| 119 | self.logger.info('a notify event message - topic (%s)' % topic) |
| 120 | if topic: |
| 121 | handler = self.handlers['notify'] |
| 122 | if callable(handler): |
| 123 | self.logger.info('calling a notify event handler - %s' % handler) |
| 124 | handler(self.workflow_id, self.workflow_run_id, topic) |
| 125 | |
Illyoung Choi | a9d2c2c | 2019-07-12 13:29:42 -0700 | [diff] [blame] | 126 | def __on_count_events_message(self, data): |
| 127 | self.__on_response(WORKFLOW_RUN_COUNT_EVENTS, data) |
| 128 | |
| 129 | def __on_fetch_event_message(self, data): |
| 130 | self.__on_response(WORKFLOW_RUN_FETCH_EVENT, data) |
| 131 | |
| 132 | def __check_pending_request(self, req_id): |
| 133 | """ |
| 134 | Check a pending request |
| 135 | """ |
| 136 | if req_id in self.pending_requests: |
| 137 | return True |
| 138 | return False |
| 139 | |
| 140 | def __put_pending_request(self, api, params): |
| 141 | """ |
| 142 | Put a pending request to a queue |
| 143 | """ |
| 144 | req_id = self.__get_next_req_id() |
| 145 | latch = CountDownLatch() |
| 146 | params['req_id'] = req_id # inject req_id |
| 147 | self.sio.emit(api, params) |
| 148 | self.pending_requests[req_id] = { |
| 149 | 'req_id': req_id, |
| 150 | 'latch': latch, |
| 151 | 'api': api, |
| 152 | 'params': params, |
| 153 | 'result': None |
| 154 | } |
| 155 | return req_id |
| 156 | |
| 157 | def __wait_response(self, req_id): |
| 158 | """ |
| 159 | Wait for completion of a request |
| 160 | """ |
| 161 | if req_id in self.pending_requests: |
| 162 | req = self.pending_requests[req_id] |
| 163 | # python v 3.2 or below does not return a result |
| 164 | # that tells whether it is timedout or not |
| 165 | return req['latch'].wait(WAIT_TIMEOUT) |
| 166 | else: |
| 167 | self.logger.error( |
| 168 | 'cannot find a pending request (%s) from a queue' % req_id |
| 169 | ) |
| 170 | raise ClientRPCError( |
| 171 | req_id, |
| 172 | 'cannot find a pending request (%s) from a queue' % req_id |
| 173 | ) |
| 174 | |
| 175 | def __complete_request(self, req_id, result): |
| 176 | """ |
| 177 | Compelete a pending request |
| 178 | """ |
| 179 | if req_id in self.pending_requests: |
| 180 | req = self.pending_requests[req_id] |
| 181 | req['latch'].count_down() |
| 182 | req['result'] = result |
| 183 | return |
| 184 | |
| 185 | self.logger.error( |
| 186 | 'cannot find a pending request (%s) from a queue' % req_id |
| 187 | ) |
| 188 | raise ClientRPCError( |
| 189 | req_id, |
| 190 | 'cannot find a pending request (%s) from a queue' % req_id |
| 191 | ) |
| 192 | |
| 193 | def __pop_pending_request(self, req_name): |
| 194 | """ |
| 195 | Pop a pending request from a queue |
| 196 | """ |
| 197 | return self.pending_requests.pop(req_name, None) |
| 198 | |
| 199 | def connect(self, url): |
| 200 | """ |
| 201 | Connect to the given url |
| 202 | """ |
| 203 | query_string = 'id=%s&type=workflow_run&name=%s&workflow_id=%s&workflow_run_id=%s' % \ |
| 204 | (self.name, self.name, self.workflow_id, self.workflow_run_id) |
| 205 | connect_url = '%s?%s' % (url, query_string) |
| 206 | |
| 207 | if not (connect_url.startswith('http://') or connect_url.startswith('https://')): |
| 208 | connect_url = 'http://%s' % connect_url |
| 209 | |
| 210 | self.logger.debug('Connecting to a Socket.IO server (%s)' % connect_url) |
| 211 | self.sio.connect(url=connect_url, transports=['websocket']) |
| 212 | |
| 213 | def disconnect(self): |
| 214 | """ |
| 215 | Disconnect from the server |
| 216 | """ |
| 217 | self.sio.disconnect() |
| 218 | |
| 219 | def wait(self): |
| 220 | self.sio.wait() |
| 221 | |
| 222 | def sleep(self, sec): |
| 223 | self.sio.sleep(sec) |
| 224 | |
| 225 | def get_handlers(self): |
| 226 | return self.handlers |
| 227 | |
| 228 | def set_handlers(self, new_handlers): |
| 229 | for k in self.handlers: |
| 230 | if k in new_handlers: |
| 231 | self.handlers[k] = new_handlers[k] |
| 232 | |
| 233 | def __request(self, api, params={}): |
| 234 | if api and params: |
| 235 | req_id = self.__put_pending_request(api, params) |
| 236 | self.logger.debug('waiting for a response for req_id (%s)' % req_id) |
| 237 | self.__wait_response(req_id) # wait for completion |
| 238 | req = self.__pop_pending_request(req_id) |
| 239 | if req: |
| 240 | if req['latch'].get_count() > 0: |
| 241 | # timed out |
| 242 | self.logger.error('request (%s) timed out' % req_id) |
| 243 | raise ClientRPCError( |
| 244 | req_id, |
| 245 | 'request (%s) timed out' % req_id |
| 246 | ) |
| 247 | else: |
| 248 | return req['result'] |
| 249 | else: |
| 250 | self.logger.error('cannot find a pending request (%s) from a queue' % req_id) |
| 251 | raise ClientRPCError( |
| 252 | req_id, |
| 253 | 'cannot find a pending request (%s) from a queue' % req_id |
| 254 | ) |
| 255 | else: |
| 256 | self.logger.error( |
| 257 | 'invalid arguments api (%s), params (%s)' % |
| 258 | (api, json.dumps(params)) |
| 259 | ) |
| 260 | raise ClientInputError( |
| 261 | 'invalid arguments api (%s), params (%s)' % |
| 262 | (api, json.dumps(params)) |
| 263 | ) |
| 264 | |
| 265 | def __on_response(self, api, result): |
| 266 | if result and 'req_id' in result: |
| 267 | self.logger.debug('completing a request (%s)' % result['req_id']) |
| 268 | self.__complete_request(result['req_id'], result) |
| 269 | else: |
| 270 | self.logger.error( |
| 271 | 'invalid arguments api (%s), result (%s)' % |
| 272 | (api, json.dumps(result)) |
| 273 | ) |
| 274 | raise ClientInputError( |
| 275 | 'invalid arguments api (%s), result (%s)' % |
| 276 | (api, json.dumps(result)) |
| 277 | ) |
| 278 | |
Illyoung Choi | a9d2c2c | 2019-07-12 13:29:42 -0700 | [diff] [blame] | 279 | def count_events(self): |
| 280 | """ |
| 281 | Count events. |
| 282 | """ |
| 283 | result = self.__request(WORKFLOW_RUN_COUNT_EVENTS, { |
| 284 | 'workflow_id': self.workflow_id, |
| 285 | 'workflow_run_id': self.workflow_run_id |
| 286 | }) |
| 287 | if result['error']: |
| 288 | self.logger.error( |
| 289 | 'request (%s) failed with an error - %s' % |
| 290 | (result['req_id'], result['message']) |
| 291 | ) |
| 292 | raise ClientResponseError( |
| 293 | 'request (%s) failed with an error - %s' % |
| 294 | (result['req_id'], result['message']) |
| 295 | ) |
| 296 | else: |
| 297 | return result['result'] |
| 298 | |
| 299 | def fetch_event(self, task_id, topic): |
| 300 | """ |
| 301 | Fetch an event. |
| 302 | """ |
| 303 | if task_id and topic: |
| 304 | result = self.__request(WORKFLOW_RUN_FETCH_EVENT, { |
| 305 | 'workflow_id': self.workflow_id, |
| 306 | 'workflow_run_id': self.workflow_run_id, |
| 307 | 'task_id': task_id, |
| 308 | 'topic': topic |
| 309 | }) |
| 310 | if result['error']: |
| 311 | self.logger.error( |
| 312 | 'request (%s) failed with an error - %s' % |
| 313 | (result['req_id'], result['message']) |
| 314 | ) |
| 315 | raise ClientResponseError( |
| 316 | 'request (%s) failed with an error - %s' % |
| 317 | (result['req_id'], result['message']) |
| 318 | ) |
| 319 | else: |
| 320 | return result['result'] |
| 321 | else: |
| 322 | self.logger.error( |
| 323 | 'invalid arguments task_id (%s), topic (%s)' % |
| 324 | (task_id, topic) |
| 325 | ) |
| 326 | raise ClientInputError( |
| 327 | 'invalid arguments task_id (%s), topic (%s)' % |
| 328 | (task_id, topic) |
| 329 | ) |