## odcs.export()


The contract of [node](nodes.NodeStatus.md#sverify.nodes.NodeStatus.node) as an ODCS document (`ODCS_VERSION`).


Usage

``` python
odcs.export(
    node,
    *,
    id=None,
    version="1.0.0",
    status="active",
    description=None,
    descriptions=None
)
```


One schema object, named after the node, with a property per column: its logical and physical (DuckDB) type, `required` where the node proves the column NOT NULL, and `primaryKey` or [unique](unique.md#sverify.unique) for its keys. Value sets become `invalidValues` rules, row caps `rowCount` rules, keys over several columns `duplicateValues` rules, and other row conditions `sql` rules (`SELECT COUNT(*) FROM {object} WHERE NOT COALESCE(<condition>, FALSE)`, which must be 0). Every flag and rule carries the custom property `sverify` with its [status](Node.status.md#sverify.Node.status): [proved](Report.proved.md#sverify.Report.proved), `checked` (on the data, `on_unproved="check"`) or `declared`. The document's own `sverify` property names the node, the plan's sha256 (as the sink's contract record has it) and whether the whole contract is proved.


## Parameters


`node: Node`  
A node with a contract (a transform's result, stored or not).

`id: str | None = None`  
The contract's `id`. Default: a UUID derived from the node's name, the same on every export.

`version: str = ``"1.0.0"`  
The contract's `version`. Default "1.0.0".

`status: str = ``"active"`  
The contract's [status](Node.status.md#sverify.Node.status). Default "active".

`description: str | None = None`  
The dataset's purpose (`description.purpose` and the schema object's `description`). Default: the first paragraph of the transform's docstring, if any.

`descriptions: Mapping[str, str] | None = None`  
A description per column, by name.


## Returns


`dict[str, Any]`  
The document as a dict, ready for `json.dump` or `yaml.safe_dump`.


## Raises


`ValueError`  
[node](nodes.NodeStatus.md#sverify.nodes.NodeStatus.node) has no contract (a source, or a transform without one).