Open Data Contract Standard (Python)

3.1.2 · active · verified Sun Apr 12

The `open-data-contract-standard` Python library provides a Pydantic model for reading and writing YAML files conforming to the Open Data Contract Standard (ODCS). It's extracted from the Data Contract CLI and its version number mirrors the major and minor versions of the ODCS it supports. The library is actively maintained, currently at version 3.1.2, supporting ODCS v3.1.0 and above.

Warnings

gotcha The pip module version mirrors the major and minor versions of the Open Data Contract Standard (ODCS) it supports, but specifically does NOT mirror the patch version. For instance, ODCS v3.1.0 might correspond to pip module versions >=3.1.0 but not necessarily 3.1.0 exactly.
Fix: Always check the PyPI page or GitHub README for the exact version mapping between the pip module and the ODCS specification version it implements.
breaking Migration from ODCS v2.x to v3.x involved significant breaking changes in the standard's schema, which the `open-data-contract-standard` Python library (v3.x and above) enforces. Key changes include renaming `uuid` to `id`, `columns` to `properties`, and changing the `team` (formerly `stakeholders`) structure from an array to an object.
Fix: Review the ODCS v3.0.0 changelog for a comprehensive list of breaking changes. Update your data contract YAML files to conform to the ODCS v3.x specification.
breaking ODCS v3.1.0 introduced stricter JSON Schema validation, disallowing additional or undefined properties in certain sections of the contract. While v3.1.0 was declared backward compatible with v3.0.x, contracts that previously contained extra, undefined fields (and were thus valid under a looser schema) will now fail validation.
Fix: Ensure your data contracts strictly adhere to the ODCS v3.1.0 (or later) JSON Schema, removing any properties not explicitly defined in the standard. Review the ODCS v3.1.0 release notes for details on stricter validation.
deprecated In ODCS v3.1.0, `slaDefaultElement` and the top-level `dataProduct` fields were deprecated. While still functional, they will generate warnings and are slated for removal in future major versions (e.g., ODCS v4).
Fix: Avoid using `slaDefaultElement` and the top-level `dataProduct`. Consult the latest ODCS documentation for recommended alternatives or replacements.

Install

pip install open-data-contract-standard Install stable version

Imports

OpenDataContractStandard

from open_data_contract_standard.model import OpenDataContractStandard

The main Pydantic model for the data contract.

Quickstart

This quickstart demonstrates how to load an Open Data Contract Standard (ODCS) specification from a string using the `OpenDataContractStandard` Pydantic model and then print it back as a YAML string. It includes comments for how to load from a file, which requires an existing YAML file.

from open_data_contract_standard.model import OpenDataContractStandard

# Example 1: Load a data contract specification from a string
data_contract_str = """
version: 1.0.0
kind: DataContract
id: 53581432-6c55-4ba2-a65f-72344a91553b
status: active
name: my_table
apiVersion: v3.1.0
"""
data_contract_from_string = OpenDataContractStandard.from_string(data_contract_str)
print("--- Data Contract from string ---")
print(data_contract_from_string.to_yaml())

# Example 2: To load from a file, you would use from_file
# Ensure 'data_contract.yaml' exists in the same directory
# with valid ODCS content for this to run without error.
# import os
# file_path = 'data_contract.yaml'
# with open(file_path, 'w') as f:
#    f.write(data_contract_str)
# data_contract_from_file = OpenDataContractStandard.from_file(file_path)
# print("\n--- Data Contract from file ---")
# print(data_contract_from_file.to_yaml())
# os.remove(file_path) # Clean up file

view raw JSON →