asynchronous refactoring

- don't execute celery tasks directly
- introduce optional parameters to fileserver tasks to allow chaining
- handle user/group/key create and delete tasks in new osusers.signals
  class
- adapt unit tests
- change TaskResults model to store the task signatures
- generalize the local settings' logging configuration

gnuviechadmin/osusers/signals.py

@@ -0,0 +1,160 @@
+"""
+This module contains the signal handlers of the :py:mod:`osusers` app.
+
+"""
+from __future__ import absolute_import, unicode_literals
+
+import logging
+
+from django.db.models.signals import (
+    m2m_changed,
+    post_delete,
+    post_save,
+)
+from django.dispatch import receiver
+
+from celery import chain, group
+
+from fileservertasks.tasks import (
+    delete_file_mail_userdir,
+    delete_file_sftp_userdir,
+    set_file_ssh_authorized_keys,
+    setup_file_mail_userdir,
+    setup_file_sftp_userdir,
+)
+from ldaptasks.tasks import (
+    add_ldap_user_to_group,
+    create_ldap_group,
+    create_ldap_user,
+    delete_ldap_group,
+    delete_ldap_user,
+    remove_ldap_user_from_group,
+    set_ldap_user_password,
+)
+from taskresults.models import TaskResult
+
+from .models import (
+    AdditionalGroup,
+    Group,
+    SshPublicKey,
+    User,
+    password_set,
+)
+
+
+_LOGGER = logging.getLogger(__name__)
+
+
+@receiver(password_set, sender=User)
+def handle_user_password_set(sender, instance, password, **kwargs):
+    taskresult = TaskResult.objects.create_task_result(
+        'handle_user_password_set',
+        set_ldap_user_password.s(instance.username, password))
+    _LOGGER.info(
+        'LDAP password change has been requested in task %s',
+        taskresult.task_id)
+
+
+#@receiver(post_save)
+#def handle_post_save(sender, **kwargs):
+#    _LOGGER.debug(
+#        'handling post_save signal for %s with args %s',
+#        sender, kwargs)
+
+
+@receiver(post_save, sender=Group)
+def handle_group_created(sender, instance, created, **kwargs):
+    if created:
+        taskresult = TaskResult.objects.create_task_result(
+            'handle_group_created',
+            create_ldap_group.s(
+                instance.groupname, instance.gid, instance.descr))
+        _LOGGER.info(
+            'LDAP group creation has been requested in task %s',
+            taskresult.task_id)
+    _LOGGER.debug(
+        'group %s has been %s', instance, created and "created" or "updated")
+
+
+@receiver(post_save, sender=User)
+def handle_user_created(sender, instance, created, **kwargs):
+    if created:
+        chain = create_ldap_user.s(
+                instance.username, instance.uid, instance.group.gid,
+                instance.gecos, instance.homedir, instance.shell, None
+            ) | setup_file_sftp_userdir.s(instance.username
+            ) | setup_file_mail_userdir.s(instance.username)
+        taskresult = TaskResult.objects.create_task_result(
+            'handle_user_created', chain)
+        _LOGGER.info(
+            'LDAP user creation has been requested in task %s',
+            taskresult.task_id)
+    _LOGGER.debug(
+        'user %s has been %s', instance, created and "created" or "updated")
+
+
+@receiver(post_save, sender=AdditionalGroup)
+def handle_user_added_to_group(sender, instance, created, **kwargs):
+    if created:
+        taskresult = TaskResult.objects.create_task_result(
+            'handle_user_added_to_group',
+            add_ldap_user_to_group.s(
+                instance.user.username, instance.group.groupname))
+        _LOGGER.info(
+            'Adding user to LDAP group has been requested in task %s',
+            taskresult.task_id)
+
+
+@receiver(post_save, sender=SshPublicKey)
+@receiver(post_delete, sender=SshPublicKey)
+def handle_ssh_keys_changed(sender, instance, **kwargs):
+    sig = set_file_ssh_authorized_keys.s(
+        instance.user.username, [
+            str(key) for key in
+            SshPublicKey.objects.filter(user=instance.user)])
+    taskresult = TaskResult.objects.create_task_result(
+        'handle_ssh_keys_changed', sig)
+    _LOGGER.info(
+        'Change of SSH keys has been requested in task %s',
+        taskresult.task_id)
+
+
+#@receiver(post_delete)
+#def handle_post_delete(sender, **kwargs):
+#    _LOGGER.debug(
+#        'handling post_delete signal for %s with args %s',
+#        sender, kwargs)
+
+
+@receiver(post_delete, sender=Group)
+def handle_group_deleted(sender, instance, **kwargs):
+    taskresult = TaskResult.objects.create_task_result(
+        'handle_group_deleted',
+        delete_ldap_group.s(instance.groupname))
+    _LOGGER.info(
+        'LDAP group deletion has been requested in task %s',
+        taskresult.task_id)
+
+
+@receiver(post_delete, sender=User)
+def handle_user_deleted(sender, instance, **kwargs):
+    chain = delete_file_mail_userdir.s(instance.username
+        ) | delete_file_sftp_userdir.s(instance.username
+        ) | delete_ldap_user.s(instance.username)
+    _LOGGER.debug('chain signature %s', chain)
+    taskresult = TaskResult.objects.create_task_result(
+        'handle_user_deleted', chain)
+    _LOGGER.info(
+        'LDAP user deletion has been requested in task %s',
+        taskresult.task_id)
+
+
+@receiver(post_delete, sender=AdditionalGroup)
+def handle_user_removed_from_group(sender, instance, **kwargs):
+    taskresult = TaskResult.objects.create_task_result(
+        'handle_user_removed_from_group',
+        remove_ldap_user_from_group.s(
+            instance.user.username, instance.group.groupname))
+    _LOGGER.info(
+        'Removing user from LDAP group has been requested in task %s',
+        taskresult.task_id)