Add purgelock management command. Closes GitLab issue #221.

Signed-off-by: Roberto Rosario <roberto.rosario.gonzalez@gmail.com>

HISTORY.rst

@@ -8,7 +8,8 @@ XX (2017-XX-XX)
 - Fix role creation API endpoint not returning id. GitLab issue #390.
 - Make tags, metadata types and cabinets searchable via the dynamic search API. GitLab issue #344.
 - Add support for updating configuration options from environment variables.
-
+- Add purgelocks management command. GitLab issue #221.
+ 
 2.3 (2017-06-08)
 ================
 - Allow for bigger indexing expression templates.

mayan/apps/lock_manager/backends/base.py

@@ -0,0 +1,15 @@
+from __future__ import unicode_literals
+
+
+class LockingBackend(object):
+    """
+    Base class for the lock backends. Defines the base methods that each
+    subclass must define.
+    """
+    @classmethod
+    def acquire_lock(cls, name, timeout=None):
+        raise NotImplementedError
+
+    @classmethod
+    def purge_locks(cls):
+        raise NotImplementedError

mayan/apps/lock_manager/backends/file_lock.py

@@ -13,6 +13,8 @@ from common.settings import setting_temporary_directory
 
 from ..exceptions import LockError
 
+from .base import LockingBackend
+
 lock = threading.Lock()
 logger = logging.getLogger(__name__)
 
@@ -23,7 +25,7 @@ open(lock_file, 'a').close()
 logger.debug('lock_file: %s', lock_file)
 
 
-class FileLock(object):
+class FileLock(LockingBackend):
     lock_file = lock_file
 
     @classmethod
@@ -31,6 +33,15 @@ class FileLock(object):
         instance = FileLock(name=name, timeout=timeout)
         return instance
 
+    @classmethod
+    def purge_locks(cls):
+        lock.acquire()
+        with open(cls.lock_file, 'r+') as file_object:
+            locks.lock(f=file_object, flags=locks.LOCK_EX)
+            file_object.seek(0)
+            file_object.truncate()
+            lock.release()
+
     def _get_lock_dictionary(self):
         if self.timeout:
             result = {

mayan/apps/lock_manager/backends/model_lock.py

@@ -2,9 +2,16 @@ from __future__ import unicode_literals
 
 from django.apps import apps
 
+from .base import LockingBackend
 
-class ModelLock(object):
+
+class ModelLock(LockingBackend):
     @classmethod
     def acquire_lock(cls, name, timeout=None):
         Lock = apps.get_model(app_label='lock_manager', model_name='Lock')
         return Lock.objects.acquire_lock(name=name, timeout=timeout)
+
+    @classmethod
+    def purge_locks(cls):
+        Lock = apps.get_model(app_label='lock_manager', model_name='Lock')
+        Lock.objects.select_for_update().delete()

mayan/apps/lock_manager/management/commands/purgelocks.py

@@ -0,0 +1,12 @@
+from __future__ import unicode_literals
+
+from django.core import management
+
+from ...runtime import locking_backend
+
+
+class Command(management.BaseCommand):
+    help = 'Erase all locks (acquired and stale).'
+
+    def handle(self, *args, **options):
+        locking_backend.purge_locks()