# Buggy code
def create_or_update_trigger_db(trigger):
    """
    Create a new TriggerDB model if one doesn't exist yet or update existing
    one.

    :param trigger: Trigger info.
    :type trigger: ``dict``
    """
    assert isinstance(trigger, dict)

    existing_trigger_db = _get_trigger_db(trigger)

    if existing_trigger_db:
        is_update = True
    else:
        is_update = False

    trigger_api = TriggerAPI(**trigger)
    trigger_api.validate()
    trigger_db = TriggerAPI.to_model(trigger_api)

    if is_update:
        trigger_db.id = existing_trigger_db.id

    trigger_db = Trigger.add_or_update(trigger_db)

    extra = {"trigger_db": trigger_db}

    if is_update:
        LOG.audit("Trigger updated. Trigger.id=%s" % (trigger_db.id), extra=extra)
    else:
        LOG.audit("Trigger created. Trigger.id=%s" % (trigger_db.id), extra=extra)

    return trigger_db


# Traceback (NotUniqueError)
Registering content...[flags = --config-file /etc/st2/st2.conf --register-all]
2017-11-10 16:04:14,401 INFO [-] Connecting to database "st2" @ "127.0.0.1:27017" as user "stackstorm".
2017-11-10 16:04:20,355 ERROR [-] Conflict while trying to save in DB.
Traceback (most recent call last):
File "/opt/stackstorm/st2/local/lib/python2.7/site-packages/st2common/persistence/base.py", line 173, in add_or_update
model_object = cls._get_impl().add_or_update(model_object)
File "/opt/stackstorm/st2/local/lib/python2.7/site-packages/st2common/models/db/__init__.py", line 336, in add_or_update
instance.save()
File "/opt/stackstorm/st2/local/lib/python2.7/site-packages/mongoengine/document.py", line 364, in save
raise NotUniqueError(message % six.text_type(err))
NotUniqueError: Tried to save duplicate unique keys (E11000 duplicate key error collection: st2.trigger_type_d_b index: uid_1 dup key: { : "trigger_type:core:st2.key_value_pair.update" })
2017-11-10 16:04:20,432 ERROR [-] Conflict while trying to save in DB.
Traceback (most recent call last):
File "/opt/stackstorm/st2/local/lib/python2.7/site-packages/st2common/persistence/base.py", line 173, in add_or_update
model_object = cls._get_impl().add_or_update(model_object)
File "/opt/stackstorm/st2/local/lib/python2.7/site-packages/st2common/models/db/__init__.py", line 336, in add_or_update
instance.save()
File "/opt/stackstorm/st2/local/lib/python2.7/site-packages/mongoengine/document.py", line 364, in save
raise NotUniqueError(message % six.text_type(err))
NotUniqueError: Tried to save duplicate unique keys (E11000 duplicate key error collection: st2.trigger_d_b index: uid_1 dup key: { : "trigger:core:st2.key_value_pair.value_change:99914b932bd37a50b983c5e7c90ae93b" })
2017-11-10 16:04:20,451 ERROR [-] Conflict while trying to save in DB.
Traceback (most recent call last):
File "/opt/stackstorm/st2/local/lib/python2.7/site-packages/st2common/persistence/base.py", line 173, in add_or_update
model_object = cls._get_impl().add_or_update(model_object)
File "/opt/stackstorm/st2/local/lib/python2.7/site-packages/st2common/models/db/__init__.py", line 336, in add_or_update
instance.save()
File "/opt/stackstorm/st2/local/lib/python2.7/site-packages/mongoengine/document.py", line 364, in save
raise NotUniqueError(message % six.text_type(err))
NotUniqueError: Tried to save duplicate unique keys (E11000 duplicate key error collection: st2.trigger_type_d_b index: uid_1 dup key: { : "trigger_type:core:st2.key_value_pair.delete" })
2017-11-10 16:04:20,567 INFO [-] =========================================================
2017-11-10 16:04:20,568 INFO [-] ############## Registering triggers #####################
2017-11-10 16:04:20,568 INFO [-] =========================================================
2017-11-10 16:04:20,673 INFO [-] Registered 0 triggers.

# Fixed code
def create_or_update_trigger_db(trigger, log_not_unique_error_as_debug=False):
    """
    Create a new TriggerDB model if one doesn't exist yet or update existing
    one.

    :param trigger: Trigger info.
    :type trigger: ``dict``
    """
    assert isinstance(trigger, dict)

    existing_trigger_db = _get_trigger_db(trigger)

    if existing_trigger_db:
        is_update = True
    else:
        is_update = False

    trigger_api = TriggerAPI(**trigger)
    trigger_api.validate()
    trigger_db = TriggerAPI.to_model(trigger_api)

    if is_update:
        trigger_db.id = existing_trigger_db.id

    trigger_db = Trigger.add_or_update(
        trigger_db, log_not_unique_error_as_debug=log_not_unique_error_as_debug
    )

    extra = {"trigger_db": trigger_db}

    if is_update:
        LOG.audit("Trigger updated. Trigger.id=%s" % (trigger_db.id), extra=extra)
    else:
        LOG.audit("Trigger created. Trigger.id=%s" % (trigger_db.id), extra=extra)

    return trigger_db