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      Licensed under the Apache License, Version 2.0 (the "License"); you may
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      under the License.

Notifications
=============

Notifications can be generated for several events in the image lifecycle.
These can be used for auditing, troubleshooting, etc.

Strategies
----------

* logging

  This strategy uses the standard Python logging infrastructure with
  the notifications ending up in file specificed by the log_file
  configuration directive.

* rabbit

  This strategy sends notifications to a rabbitmq queue. This can then
  be processed by other services or applications.

* qpid

  This strategy is similar to rabbit. It sends notifications to an AMQP
  message queue via Qpid.

* noop

  This strategy produces no notifications. It is the default strategy.

Notification Types
------------------

* ``image.create``

  Emitted when an image record is created in Glance.  Image record creation is
  independent of image data upload.

* ``image.prepare``

  Emitted when Glance begins uploading image data to its store.

* ``image.upload``

  Emitted when Glance has completed the upload of image data to its store.

* ``image.activate``

  Emitted when an image goes to `active` status.  This occurs when Glance
  knows where the image data is located.

* ``image.send``

  Emitted upon completion of an image being sent to a consumer.

* ``image.update``

  Emitted when an image record is updated in Glance.

* ``image.delete``

  Emitted when an image deleted from Glance.


Content
-------

Every message contains a handful of attributes.

* message_id

  UUID identifying the message.

* publisher_id

  The hostname of the glance instance that generated the message.

* event_type

  Event that generated the message.

* priority

  One of WARN, INFO or ERROR.

* timestamp

  UTC timestamp of when event was generated.

* payload

  Data specific to the event type.

Payload
-------

* image.send

  The payload for INFO, WARN, and ERROR events contain the following:

  image_id
    ID of the image (UUID)
  owner_id
    Tenant or User ID that owns this image (string)
  receiver_tenant_id
    Tenant ID of the account receiving the image (string)
  receiver_user_id
    User ID of the account receiving the image (string)
    destination_ip
  bytes_sent
    The number of bytes actually sent

* image.create

  For INFO events, it is the image metadata.
  WARN and ERROR events contain a text message in the payload.

* image.prepare

  For INFO events, it is the image metadata.
  WARN and ERROR events contain a text message in the payload.

* image.upload

  For INFO events, it is the image metadata.
  WARN and ERROR events contain a text message in the payload.

* image.activate

  For INFO events, it is the image metadata.
  WARN and ERROR events contain a text message in the payload.

* image.update

  For INFO events, it is the image metadata.
  WARN and ERROR events contain a text message in the payload.

* image.delete

  For INFO events, it is the image id.
  WARN and ERROR events contain a text message in the payload.