Merge pull request #12 from cuda-networks/process-queue-command

Process queue Django Command

README.md

@@ -4,7 +4,7 @@ django-eb-sqs is a simple task manager for the Elastic Beanstalk Worker Tier. It
 
 ### Installation
 
-Install the module with `pip install django-eb-sqs` or add it to your `requirements.txt`.
+Install the module with `pip install git+git://github.com/cuda-networks/django-eb-sqs.git` or add it to your `requirements.txt`.
 
 Don't forget to add django-eb-sqs app to your Django `INSTALLED_APPS` settings:
 ```python
@@ -94,6 +94,17 @@ For example:
 python manage.py run_eb_sqs_worker --url http://127.0.0.1:80/worker/process --queue default
 ```
 
+#### Executing Tasks without Elastic Beanstalk
+
+Another way of executing tasks is to use the Django command `process_queue`.
+This command can work with one or more queues, reading from the queues infinitely and executing tasks as they come-in.
+
+```bash
+python manage.py process_queue --queues <comma-delimited list of queue names>
+```
+
+This is a good idea for someone who wants to execute tasks without an Elastic Beanstalk worker.
+
 
 #### Group Tasks
 Multiple tasks can be grouped by specifing the `group_id` argument when calling `delay` on a task.
@@ -119,6 +130,9 @@ def group_finished(group_id):
 
 The following settings can be used to fine tune django-eb-sqs. Copy them into your Django `settings.py` file.
 
+- EB_AWS_REGION (`us-east-1`): The AWS region to use when working with SQS.
+- EB_SQS_MAX_NUMBER_OF_MESSAGES (`10`): The maximum number of messages to read in a single call from SQS (<= 10).
+- EB_SQS_WAIT_TIME_S (`2`): The time to wait (seconds) when receiving messages from SQS.
 - EB_SQS_AUTO_ADD_QUEUE (`True`): If queues should be added automatically to AWS if they don't exist.
 - EB_SQS_DEAD_LETTER_MODE (`False`): Enable if this worker is handling the SQS dead letter queue. Tasks won't be executed but group callback is.
 - EB_SQS_DEFAULT_DELAY (`0`): Default task delay time in seconds.

development.txt

@@ -1,5 +1,5 @@
-boto3==1.3.1
-Django==1.9.6
+boto3==1.4.4
+Django==1.10.6
 mock==2.0.0
 moto==0.4.24
 redis==2.10.5

eb_sqs/management/commands/process_queue.py

@@ -0,0 +1,58 @@
+from __future__ import absolute_import, unicode_literals
+
+import boto3
+import logging
+
+from django.core.management import BaseCommand, CommandError
+
+from eb_sqs import settings
+from eb_sqs.worker.worker import Worker
+from eb_sqs.worker.worker_factory import WorkerFactory
+
+logger = logging.getLogger(__name__)
+
+
+class Command(BaseCommand):
+    help = 'Command to process tasks from one or more SQS queues'
+
+    def add_arguments(self, parser):
+        parser.add_argument('--queues', '-q',
+                            dest='queue_names',
+                            help='Name of queues to process, separated by commas')
+
+    def handle(self, *args, **options):
+        if not options['queue_names']:
+            raise CommandError('Queue names (--queues) not specified')
+
+        queue_names = [queue_name.rstrip() for queue_name in options['queue_names'].split(',')]
+
+        logger.debug('[django-eb-sqs] Connecting to SQS: {}'.format(', '.join(queue_names)))
+
+        sqs = boto3.resource('sqs', region_name=settings.AWS_REGION)
+        queues = [sqs.get_queue_by_name(QueueName=queue_name) for queue_name in queue_names]
+
+        logger.debug('[django-eb-sqs] Connected to SQS: {}'.format(', '.join(queue_names)))
+
+        worker = WorkerFactory.default().create()
+
+        while True:
+            for queue in queues:
+                messages = queue.receive_messages(
+                    MaxNumberOfMessages=settings.MAX_NUMBER_OF_MESSAGES,
+                    WaitTimeSeconds=settings.WAIT_TIME_S,
+                )
+
+                for msg in messages:
+                    self._process_message(msg, worker)
+
+    def _process_message(self, msg, worker):
+        # type: (Any, Worker) -> None
+        logger.debug('[django-eb-sqs] Read message {}'.format(msg.message_id))
+        try:
+            worker.execute(msg.body)
+            logger.debug('[django-eb-sqs] Processed message {}'.format(msg.message_id))
+        except Exception as exc:
+            logger.error('[django-eb-sqs] Unhandled error: {}'.format(exc), exc_info=1)
+        finally:
+            msg.delete()
+            logger.debug('[django-eb-sqs] Deleted message {}'.format(msg.message_id))

eb_sqs/settings.py

@@ -2,26 +2,31 @@
 
 from django.conf import settings
 
-AUTO_ADD_QUEUE = getattr(settings, 'EB_SQS_AUTO_ADD_QUEUE', True) # type: bool
-QUEUE_PREFIX = getattr(settings, 'EB_SQS_QUEUE_PREFIX', 'eb-sqs-') # type: unicode
-DEFAULT_QUEUE = getattr(settings, 'EB_SQS_DEFAULT_QUEUE', 'default') # type: unicode
+AWS_REGION = getattr(settings, 'EB_AWS_REGION', 'us-east-1')  # type: unicode
 
-EXECUTE_INLINE = getattr(settings, 'EB_SQS_EXECUTE_INLINE', False) # type: bool
-FORCE_SERIALIZATION = getattr(settings, 'EB_SQS_FORCE_SERIALIZATION', False) # type: bool
+MAX_NUMBER_OF_MESSAGES = getattr(settings, 'EB_SQS_MAX_NUMBER_OF_MESSAGES', 10)  # type: int
+WAIT_TIME_S = getattr(settings, 'EB_SQS_WAIT_TIME_S', 2)  # type: int
 
-DEFAULT_DELAY = getattr(settings, 'EB_SQS_DEFAULT_DELAY', 0) # type: int
-DEFAULT_MAX_RETRIES = getattr(settings, 'EB_SQS_DEFAULT_MAX_RETRIES', 0) # type: int
-DEFAULT_COUNT_RETRIES = getattr(settings, 'EB_SQS_DEFAULT_COUNT_RETRIES', True) # type: bool
+AUTO_ADD_QUEUE = getattr(settings, 'EB_SQS_AUTO_ADD_QUEUE', True)  # type: bool
+QUEUE_PREFIX = getattr(settings, 'EB_SQS_QUEUE_PREFIX', 'eb-sqs-')  # type: unicode
+DEFAULT_QUEUE = getattr(settings, 'EB_SQS_DEFAULT_QUEUE', 'default')  # type: unicode
 
-USE_PICKLE = getattr(settings, 'EB_SQS_USE_PICKLE', False) # type: bool
+EXECUTE_INLINE = getattr(settings, 'EB_SQS_EXECUTE_INLINE', False)  # type: bool
+FORCE_SERIALIZATION = getattr(settings, 'EB_SQS_FORCE_SERIALIZATION', False)  # type: bool
 
-GROUP_CALLBACK_TASK = getattr(settings, 'EB_SQS_GROUP_CALLBACK_TASK', None) # type: Any
+DEFAULT_DELAY = getattr(settings, 'EB_SQS_DEFAULT_DELAY', 0)  # type: int
+DEFAULT_MAX_RETRIES = getattr(settings, 'EB_SQS_DEFAULT_MAX_RETRIES', 0)  # type: int
+DEFAULT_COUNT_RETRIES = getattr(settings, 'EB_SQS_DEFAULT_COUNT_RETRIES', True)  # type: bool
 
-REDIS_CLIENT = getattr(settings, 'EB_SQS_REDIS_CLIENT', None) # type: StrictRedis
+USE_PICKLE = getattr(settings, 'EB_SQS_USE_PICKLE', False)  # type: bool
+
+GROUP_CALLBACK_TASK = getattr(settings, 'EB_SQS_GROUP_CALLBACK_TASK', None)  # type: Any
+
+REDIS_CLIENT = getattr(settings, 'EB_SQS_REDIS_CLIENT', None)  # type: StrictRedis
 # default: 7 days
-REDIS_EXPIRY = getattr(settings, 'EB_SQS_REDIS_EXPIRY', 3600*24*7) # type: int
-REDIS_KEY_PREFIX = getattr(settings, 'EB_SQS_REDIS_KEY_PREFIX', 'eb-sqs-') # type: string
+REDIS_EXPIRY = getattr(settings, 'EB_SQS_REDIS_EXPIRY', 3600 * 24 * 7)  # type: int
+REDIS_KEY_PREFIX = getattr(settings, 'EB_SQS_REDIS_KEY_PREFIX', 'eb-sqs-')  # type: string
 
-WORKER_FACTORY = getattr(settings, 'EB_SQS_WORKER_FACTORY', None) # type: WorkerFactory
+WORKER_FACTORY = getattr(settings, 'EB_SQS_WORKER_FACTORY', None)  # type: WorkerFactory
 
-DEAD_LETTER_MODE = getattr(settings, 'EB_SQS_DEAD_LETTER_MODE', False) # type: bool
+DEAD_LETTER_MODE = getattr(settings, 'EB_SQS_DEAD_LETTER_MODE', False)  # type: bool

setup.py

@@ -6,13 +6,13 @@
 
 setup(
     name='django-eb-sqs',
-    version='0.96',
+    version='0.97',
     package_dir={'eb_sqs': 'eb_sqs'},
     include_package_data=True,
     packages=find_packages(),
     description='A SQS worker implementation for Elastic Beanstalk',
     long_description=README,
-    url='https://github.com/sookasa/django-eb-sqs',
+    url='https://github.com/cuda-networks/django-eb-sqs',
     install_requires=[
         'boto3>=1.3.1',
         'Django>=1.7',