taipy.core.data.DataNode

Bases: _Entity

Reference to a dataset.

A Data Node is an abstract class that holds metadata related to the dataset it refers to. In particular, a data node holds the name, the scope, the owner identifier, the last edit date, and some additional properties of the data.
A Data Node also contains information and methods needed to access the dataset. This information depends on the type of storage, and it is held by subclasses (such as SQL Data Node, CSV Data Node, ...).

Note

It is recommended not to instantiate subclasses of DataNode directly.

Attributes:

Name	Type	Description
config_id	str	Identifier of the data node configuration. It must be a valid Python identifier.
scope	Scope	The scope of this data node.
id	str	The unique identifier of this data node.
name	str	A user-readable name of this data node.
owner_id	str	The identifier of the owner (pipeline_id, scenario_id, cycle_id) or None.
parent_ids	Optional[Set[str]]	The set of identifiers of the parent tasks.
last_edit_date	datetime	The date and time of the last modification.
edits	List[Edit]	The list of Edits (an alias for dict) containing medata about each edition of that node.
version	str	The string indicates the application version of the data node to instantiate. If not provided, the current version is used.
validity_period	Optional[timedelta]	The validity period of a data node. Implemented as a timedelta. If validity_period is set to None, the data_node is always up-to-date.
edit_in_progress	bool	True if the data node is locked for modification. False otherwise.
kwargs	bool	A dictionary of additional properties.

cacheable property writable

Deprecated. Use skippable attribute of a Task instead.

edition_in_progress property writable

Deprecated. Use edit_in_progress instead.

edits property

Get all Edits of the data node.

expiration_date: datetime property

Datetime instant of the expiration date of the data node.

is_ready_for_reading: bool property

Indicate if this data node is ready for reading.

Returns:

Type	Description
bool	False if the data is locked for modification or if the data has never been written. True otherwise.

is_up_to_date property

Indicate if this data node is up-to-date.

Returns:

Type	Description
	False if the data ever been written or the expiration date has passed. True otherwise.

job_ids property

List of the jobs having edited the data node.

last_edition_date property writable

Deprecated. Use last_edit_date instead.

parent_id property writable

Deprecated. Use owner_id instead.

parent_ids property

List of parent ids of the data node.

properties property

Dictionary of custom properties.

filter(operators, join_operator=JoinOperator.AND)

Read the data referenced by the data node, appying a filter.

The data is filtered by the provided list of 3-tuples (key, value, Operator).

If multiple filter operators are provided, filtered data will be joined based on the join operator (AND or OR).

Parameters:

Name	Type	Description	Default
operators	Union[List[Tuple], Tuple]	TODO	required
join_operator	JoinOperator	The operator used to join the multiple filter 3-tuples.	JoinOperator.AND

get_last_edit()

Get last Edit of the data node, or None

get_parents()

Get all parents of the data node.

lock_edit()

Lock the data node modification.

Note

The data node can be unlocked with the method unlock_edit().

lock_edition()

Deprecated. Use lock_edit instead.

read()

Read the data referenced by this data node.

Returns:

Type	Description
Any	The data referenced by this data node. None if the data has not been written yet.

read_or_raise()

Read the data referenced by this data node.

Returns:

Type	Description
Any	The data referenced by this data node.

Raises:

Type	Description
NoData	If the data has not been written yet.

unlock_edit(at=None, job_id=None)

Unlocks the data node modification.

Parameters:

Name	Type	Description	Default
at	Optional[datetime]	Deprecated.	None
job_id	Optional[JobId]	Deprecated.	None

Note

The data node can be locked with the method lock_edit().

unlock_edition(at=None, job_id=None)

Deprecated. Use unlock_edit() instead.

write(data, job_id=None, **kwargs)

Write some data to this data node.

Parameters:

Name	Type	Description	Default
data	Any	The data to write to this data node.	required
job_id	JobId	An optional identifier of the writer.	None
**kwargs		Extra information to attach to the edit document corresponding to this write.	{}