initial commit

.gitignore

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+*.pyc

LICENSE

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+MIT License
+
+Copyright (c) 2018 sankalpjonn
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

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+# Looper
+Looper is a service that can be used to run periodic tasks after a certain interval.
+
+Each job runs on a separate thread and when the service is shut down, it waits till all tasks currently being executed are completed.
+
+Inspired by this blog [`here`](https://www.g-loaded.eu/2016/11/24/how-to-terminate-running-python-threads-using-signals/)
+
+## Installation
+```sh
+python setup.py install
+```
+
+## writing a job looks like this
+
+```python
+import time
+
+from looper import Looper
+from datetime import timedelta
+
+loop = Looper()
+
+@loop.job(interval=timedelta(seconds=2))
+def sample_job_every_2s():
+    print "2s job current time : {}".format(time.ctime())
+
+@loop.job(interval=timedelta(seconds=5))
+def sample_job_every_5s():
+    print "5s job current time : {}".format(time.ctime())
+
+
+@loop.job(interval=timedelta(seconds=10))
+def sample_job_every_10s():
+    print "10s job current time : {}".format(time.ctime())
+
+loop.start()
+```
+
+## Author
+* **Sankalp Jonna**
+
+Email me with any queries: [sankalpjonna@gmail.com](sankalpjonna@gmail.com).

looper/__init__.py

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+from app import Looper

looper/app.py

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+import logging, sys, signal, time
+
+from exceptions import ServiceExit
+from job import Job
+from helpers import service_shutdown
+
+class Looper():
+    def __init__(self):
+        self.jobs = []
+        logger = logging.getLogger('looperr')
+        ch = logging.StreamHandler(sys.stdout)
+        ch.setLevel(logging.INFO)
+        formatter = logging.Formatter('[%(asctime)s] [%(name)s] [%(levelname)s] %(message)s')
+        ch.setFormatter(formatter)
+        logger.addHandler(ch)
+        logger.setLevel(logging.INFO)
+        self.logger = logger
+
+    def _add_task(self, func, interval, *args, **kwargs):
+        j = Job(interval, func, *args, **kwargs)
+        self.jobs.append(j)
+
+    def job(self, interval):
+        def decorator(f):
+            self._add_task(f, interval)
+            return f
+        return decorator
+
+    def start(self):
+        try:
+            signal.signal(signal.SIGTERM, service_shutdown)
+            signal.signal(signal.SIGINT, service_shutdown)
+
+            self.logger.info("Starting looper..")
+            for j in self.jobs:
+                self.logger.info("Registered task {}".format(j.execute))
+                j.start()
+            self.logger.info("Looper now started. Tasks will run based on the interval set")
+
+            # block main thead
+            while True:
+                time.sleep(1)
+
+        except ServiceExit:
+            for j in self.jobs:
+                self.logger.info("Stopping task {}".format(j.execute))
+                j.stop()

looper/exceptions.py

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+class ServiceExit(Exception):
+    """
+    Custom exception which is used to trigger the clean exit
+    of all running threads and the main program.
+    """
+    pass

looper/helpers.py

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+from exceptions import ServiceExit
+
+def service_shutdown(signum, frame):
+    raise ServiceExit

looper/job.py

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+from threading import Thread, Event
+from datetime import timedelta
+
+class Job(Thread):
+    def __init__(self, interval, execute, *args, **kwargs):
+        Thread.__init__(self)
+        self.stopped = Event()
+        self.interval = interval
+        self.execute = execute
+        self.args = args
+        self.kwargs = kwargs
+
+    def stop(self):
+        self.stopped.set()
+        self.join()
+
+    def run(self):
+        while not self.stopped.wait(self.interval.total_seconds()):
+            self.execute(*self.args, **self.kwargs)
+
+def sample_func(arg1, arg2, arg3):
+    print "returning {} {} {}".format(arg1, arg2, arg3)
+
+if __name__ == "__main__":
+    j = Job(timedelta(seconds=5), sample_func, **{"arg1": "sankalp", "arg2": "jonna", "arg3": "newsomething"})
+    j.start()

setup.py

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+# please install python if it is not present in the system
+from setuptools import setup
+
+with open("README.md", "r") as fh:
+    long_description = fh.read()
+
+setup(
+ name='looper',
+ version='1.0',
+ packages=['looper'],
+ license = 'MIT',
+ description = 'An elegant way to run period tasks.',
+ author = 'Sankalp Jonna',
+ author_email = 'sankalpjonna@gmail.com',
+ keywords = ['tasks','jobs','periodic task','interval','periodic job', 'flask style', 'decorator'],
+ long_description=long_description,
+ long_description_content_type="text/markdown",
+ url="https://github.com/sankalpjonn/looper",
+ include_package_data=True,
+)