+# -*- coding: utf-8 -*-
+
+# Copyright 2018 Telefonica S.A.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+# implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
import logging
import os
import yaml
import asyncio
-from msgbase import MsgBase, MsgException
+from osm_common.msgbase import MsgBase, MsgException
from time import sleep
+from http import HTTPStatus
__author__ = "Alfonso Tierno <alfonso.tiernosepulveda@telefonica.com>"
"""
This emulated kafka bus by just using a shared file system. Useful for testing or devops.
-One file is used per topic. Only one producer and one consumer is allowed per topic. Both consumer and producer
+One file is used per topic. Only one producer and one consumer is allowed per topic. Both consumer and producer
access to the same file. e.g. same volume if running with docker.
One text line per message is used in yaml format.
"""
-class MsgLocal(MsgBase):
- def __init__(self, logger_name='msg'):
- self.logger = logging.getLogger(logger_name)
+class MsgLocal(MsgBase):
+ def __init__(self, logger_name="msg", lock=False):
+ super().__init__(logger_name, lock)
self.path = None
# create a different file for each topic
- self.files = {}
+ self.files_read = {}
+ self.files_write = {}
self.buffer = {}
+ self.loop = None
def connect(self, config):
try:
self.path += "/"
if not os.path.exists(self.path):
os.mkdir(self.path)
+ self.loop = config.get("loop")
+
except MsgException:
raise
except Exception as e: # TODO refine
- raise MsgException(str(e))
+ raise MsgException(str(e), http_code=HTTPStatus.INTERNAL_SERVER_ERROR)
def disconnect(self):
- for f in self.files.values():
+ for topic, f in self.files_read.items():
+ try:
+ f.close()
+ self.files_read[topic] = None
+ except Exception: # TODO refine
+ pass
+ for topic, f in self.files_write.items():
try:
f.close()
- except Exception as e: # TODO refine
+ self.files_write[topic] = None
+ except Exception: # TODO refine
pass
def write(self, topic, key, msg):
:return: None or raises and exception
"""
try:
- if topic not in self.files:
- self.files[topic] = open(self.path + topic, "a+")
- yaml.safe_dump({key: msg}, self.files[topic], default_flow_style=True, width=20000)
- self.files[topic].flush()
+ with self.lock:
+ if topic not in self.files_write:
+ self.files_write[topic] = open(self.path + topic, "a+")
+ yaml.safe_dump(
+ {key: msg},
+ self.files_write[topic],
+ default_flow_style=True,
+ width=20000,
+ )
+ self.files_write[topic].flush()
except Exception as e: # TODO refine
- raise MsgException(str(e))
+ raise MsgException(str(e), HTTPStatus.INTERNAL_SERVER_ERROR)
def read(self, topic, blocks=True):
"""
if isinstance(topic, (list, tuple)):
topic_list = topic
else:
- topic_list = (topic, )
+ topic_list = (topic,)
while True:
for single_topic in topic_list:
- if single_topic not in self.files:
- self.files[single_topic] = open(self.path + single_topic, "a+")
+ with self.lock:
+ if single_topic not in self.files_read:
+ self.files_read[single_topic] = open(
+ self.path + single_topic, "a+"
+ )
+ self.buffer[single_topic] = ""
+ self.buffer[single_topic] += self.files_read[
+ single_topic
+ ].readline()
+ if not self.buffer[single_topic].endswith("\n"):
+ continue
+ msg_dict = yaml.safe_load(self.buffer[single_topic])
self.buffer[single_topic] = ""
- self.buffer[single_topic] += self.files[single_topic].readline()
- if not self.buffer[single_topic].endswith("\n"):
- continue
- msg_dict = yaml.load(self.buffer[single_topic])
- self.buffer[single_topic] = ""
- assert len(msg_dict) == 1
- for k, v in msg_dict.items():
- return single_topic, k, v
+ assert len(msg_dict) == 1
+ for k, v in msg_dict.items():
+ return single_topic, k, v
if not blocks:
return None
sleep(2)
except Exception as e: # TODO refine
- raise MsgException(str(e))
+ raise MsgException(str(e), HTTPStatus.INTERNAL_SERVER_ERROR)
- async def aioread(self, topic, loop):
+ async def aioread(
+ self, topic, loop=None, callback=None, aiocallback=None, group_id=None, **kwargs
+ ):
"""
Asyncio read from one or several topics. It blocks
:param topic: can be str: single topic; or str list: several topics
- :param loop: asyncio loop
- :return: topic, key, message
+ :param loop: asyncio loop. To be DEPRECATED! in near future!!! loop must be provided inside config at connect
+ :param callback: synchronous callback function that will handle the message
+ :param aiocallback: async callback function that will handle the message
+ :param group_id: group_id to use for load balancing. Can be False (set group_id to None), None (use general
+ group_id provided at connect inside config), or a group_id string
+ :param kwargs: optional keyword arguments for callback function
+ :return: If no callback defined, it returns (topic, key, message)
"""
+ _loop = loop or self.loop
try:
while True:
msg = self.read(topic, blocks=False)
if msg:
- return msg
- await asyncio.sleep(2, loop=loop)
+ if callback:
+ callback(*msg, **kwargs)
+ elif aiocallback:
+ await aiocallback(*msg, **kwargs)
+ else:
+ return msg
+ await asyncio.sleep(2, loop=_loop)
except MsgException:
raise
except Exception as e: # TODO refine
- raise MsgException(str(e))
+ raise MsgException(str(e), HTTPStatus.INTERNAL_SERVER_ERROR)
+ async def aiowrite(self, topic, key, msg, loop=None):
+ """
+ Asyncio write. It blocks
+ :param topic: str
+ :param key: str
+ :param msg: message, can be str or yaml
+ :param loop: asyncio loop
+ :return: nothing if ok or raises an exception
+ """
+ return self.write(topic, key, msg)
projects / osm / common.git / blobdiff