Event description
The Event
object in Taipy is a notification mechanism for any changes occurring within Taipy Core,
particularly those related to the Scenario and Data Management. It is a crucial part of the system that allows
tracking and responding to changes in the state of various entities managed by Taipy, such as data nodes, jobs,
and scenarios.
An Event
object is composed of several key attributes that describe what happened, the
type of operation performed, the entity concerned and its type, and other contextual
details.
-
entity_type
- Type:
EventEntityType
(Enum) -
Description: Specifies the type of entity that has undergone a change. This attribute helps identify the nature of the object affected. The possible entity types are:
CYCLE
SCENARIO
SEQUENCE
TASK
DATA_NODE
JOB
SUBMISSION
- Type:
-
operation
- Type:
EventOperation
(Enum) -
Description: Indicates the type of operation performed. The
operation
attribute is essential for understanding the nature of the change. The possible operations are:CREATION
- An entity has been created.UPDATE
- An entity has been updated.DELETION
- An entity has been deleted.SUBMISSION
- An entity has been submitted for processing.
- Type:
-
entity_id
- Type:
str
- Description: The unique identifier for the entity that has been changed. This ID allows you to precisely identify which object in the system the event refers to.
- Type:
-
attribute_name
- Type:
str
- Description: The name of the specific attribute that has been changed within
the entity. This attribute is only relevant for
UPDATE
operations, where a specific field of an entity has been modified.
- Type:
-
attribute_value
- Type:
Any
- Description: The new value of the changed attribute. Like
attribute_name
, this only applies toUPDATE
operations.
- Type:
-
metadata
- Type:
dict
- Description: A dictionary containing additional metadata about the source of the event. This can include context-specific information that provides more insight into the event's origin or purpose.
- Type:
-
creation_date
- Type:
datetime
- Description: The exact date and time the event was created.
- Type:
Scenario creation event
For example, when a scenario is created, an event is emitted with the following attributes:
entity_type
:EventEntityType.SCENARIO
operation
:EventOperation.CREATION
entity_id
: the id of the scenariocreation_date
: the date and time of the event creation
Events are particularly useful when you want to:
- Update the user interface (e.g., update a list of scenarios when a new one is created)
- Trigger an action (e.g., automatically submit a scenario when its input data is updated)
- Notify end-users (e.g., send a GUI notification to all users when a job fails)
- etc.
For more examples, see the examples page.