taipy.core.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 parent 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. |
parent_id |
str
|
The identifier of the parent (pipeline_id, scenario_id, cycle_id) or None. |
last_edit_date |
datetime
|
The date and time of the last modification. |
job_ids |
List[str]
|
The ordered list of jobs that have written this data node. |
cacheable |
bool
|
True if this data node is cacheable. False otherwise. |
validity_period |
Optional[timedelta]
|
The validity period of a cacheable 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 a task computing the data node has been submitted and not completed yet. False otherwise. |
kwargs |
bool
|
A dictionary of additional properties. |
edition_in_progress
property
writable
¶
Deprecated. Use edit_in_progress instead.
is_ready_for_reading: bool
property
¶
Indicate if this data node is ready for reading.
Returns:
| Name | Type | Description |
|---|---|---|
bool |
bool
|
False if the data is locked for modification or if the data has never been written. True otherwise. |
last_edition_date
property
writable
¶
Deprecated. Use last_edit_date instead.
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
|
lock_edit()
¶
Lock the edit of this data node.
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:
| Name | Type | Description |
|---|---|---|
Any |
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:
| Name | Type | Description |
|---|---|---|
Any |
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 edit of the data node.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
at |
datetime
|
Deprecated. |
None
|
job_id |
JobId
|
Deprecated. |
None
|
Note
The data node can be locked with the method lock_edit().
unlock_edition(at=None, job_id=None)
¶
Deprecated. Use (DataNode.)unlock_edit()^` instead.