Merge pull request #12 from thorgate/chore/update-django-lts-support

Update Django version to support latest LTS

.travis.yml

@@ -12,11 +12,14 @@ env:
   - DJANGO=1.11
   - DJANGO=2.0
   - DJANGO=2.1
+  - DJANGO=2.2
 
 matrix:
   exclude:
     - python: "3.4"
       env: DJANGO=2.1
+    - python: "3.4"
+      env: DJANGO=2.2
     - python: "3.7"
       env: DJANGO=1.8
     - python: "3.7"
@@ -45,7 +48,7 @@ deploy:
     repo: thorgate/tg-utils
     tags: true
     python: "3.6"
-    condition: "$DJANGO = 2.0"
+    condition: "$DJANGO = 2.2"
 
 notifications:
   email: false

requirements_dev.txt

@@ -10,3 +10,4 @@ pytest==2.8.5
 pytest-django==2.9.1
 django_compressor==2.0
 hashids==1.1.0
+python-redis-lock>=3.2.0,<4.0.0

setup.py

@@ -46,10 +46,11 @@
     },
     include_package_data=True,
     install_requires=[
-        'django>=1.8,!=2.1.0,!=2.1.1,<2.2',
+        'django>=1.8,!=2.1.0,!=2.1.1,<3.0',
     ],
     extras_require={
         'lock': [
+            'redis>=2.10.0',
             'python-redis-lock>=3.2.0,<4.0.0',
         ],
         'health_check': [

tg_utils/__init__.py

@@ -2,4 +2,4 @@
 
 __author__ = 'Thorgate'
 __email__ = '[email protected]'
-__version__ = '0.6.1'
+__version__ = '0.7.0'

tg_utils/lock.py

@@ -14,33 +14,37 @@
 
 
 REDIS_LOCK_URL = getattr(settings, 'REDIS_LOCK_URL', False)
-if not REDIS_LOCK_URL:
-    raise ImproperlyConfigured("To use locking, set REDIS_LOCK_URL in your settings.py")
-_redis_conn = StrictRedis.from_url(REDIS_LOCK_URL)
 
-DEFAULT_PREFIX = getattr(settings, 'REDIS_LOCK_DEFAULT_PREFIX', 'acquires_lock_')
+DEFAULT_PREFIX = getattr(settings, 'REDIS_LOCK_DEFAULT_PREFIX', 'acquires_lock')
 
 
 logger = logging.getLogger('tg-utils.lock')
 logger.setLevel(logging.DEBUG if settings.DEBUG else logging.INFO)
 
 
+def get_redis_connection():
+    if not REDIS_LOCK_URL:
+        raise ImproperlyConfigured("To use locking, set REDIS_LOCK_URL in your settings.py")
+
+    return StrictRedis.from_url(REDIS_LOCK_URL)
+
+
 def get_lock(resource, expires):
     # Seconds from now on
     if isinstance(expires, timedelta):
         expires = expires.total_seconds()
 
-    return redis_lock.Lock(_redis_conn, resource, expire=expires)
+    return redis_lock.Lock(get_redis_connection(), resource, expire=expires)
 
 
-def acquires_lock(expires, should_fail=True, should_wait=False, resource=None, prefix=DEFAULT_PREFIX):
+def acquires_lock(expires, should_fail=True, should_wait=False, resource=None, prefix=DEFAULT_PREFIX, create_id=None):
     """
     Decorator to ensure function only runs when it is unique holder of the resource.
 
     Any invocations of the functions before the first is done
     will raise RuntimeError.
 
-    Locks are stored in redis with prefix: `lock:acquires_lock`
+    Locks are stored in redis with default prefix: `lock:acquires_lock`
 
     Arguments:
         expires(timedelta|int): Expiry time of lock, way more than expected time to run.
@@ -49,6 +53,7 @@ def acquires_lock(expires, should_fail=True, should_wait=False, resource=None, p
         should_wait(bool): Should this task wait for lock to be released.
         resource(str): Resource identifier, by default taken from function name.
         prefix(str): Change prefix added to redis key (the 'lock:' part will always be added)
+        create_id(function): Change suffix added to redis key to lock only specific function call based on arguments.
 
     Example:
 
@@ -60,11 +65,6 @@ def acquires_lock(expires, should_fail=True, should_wait=False, resource=None, p
         def foo():
             ...
     """
-
-    # Seconds from now on
-    if isinstance(expires, timedelta):
-        expires = expires.total_seconds()
-
     # This is just a tiny wrapper around redis_lock
     # 1) acquire lock or fail
     # 2) run function
@@ -76,12 +76,20 @@ def decorator(f):
         if resource is None:
             resource = f.__name__
 
-        resource = '%s%s' % (prefix, resource)
+        resource = '%s:%s' % (prefix, resource)
 
         @wraps(f)
         def wrapper(*args, **kwargs):
+            lock_suffix = None
+
+            if create_id:
+                lock_suffix = create_id(*args, **kwargs)
+
             # The context manager is annoying and always blocking...
-            lock = redis_lock.Lock(_redis_conn, resource, expire=expires)
+            lock = get_lock(
+                resource='%s:%s' % (resource, lock_suffix) if lock_suffix else resource,
+                expires=expires,
+            )
             lock_acquired = False
 
             # Get default lock blocking mode
@@ -104,9 +112,11 @@ def wrapper(*args, **kwargs):
             if not lock.acquire(blocking=is_blocking):
                 if should_fail:
                     raise RuntimeError("Failed to acquire lock: %s" % resource)
+
                 logger.warning('Failed to acquire lock: %s', resource)
                 if not should_execute_if_lock_fails:
                     return False
+
             else:
                 lock_acquired = True