jsoncompat

What it is and what it does

jsoncompat is a Python binding for checking whether JSON Schemas remain compatible as they evolve, and for generating example values that satisfy a schema. It addresses the problem of schema versioning: when a schema changes over time, you need to know whether old data will still validate against the new schema (backward compatibility) or whether new data will validate against old schemas (forward compatibility). The package provides three main operations: compatibility checking between schema versions, validation of JSON instances against a schema, and generation of example values from a schema.

The package exposes a straightforward API: `check_compat()` takes two schemas and a role (serializer, deserializer, or both) and returns a boolean; `validator_for()` and `generator_for()` return reusable objects that parse the schema once and support repeated validation or generation. It also includes code generation for dataclasses that automatically handle serialization and deserialization with optional format support (JSON, YAML, MessagePack). No runtime dependencies are required for the core API.

Use it for

• Verify that a new JSON Schema version remains backward compatible with old client data before deploying schema changes
• Generate valid test data that conforms to a schema for property-based testing or integration tests
• Validate incoming JSON payloads against a schema in an API or data pipeline
• Generate Python dataclasses from JSON Schemas with built-in validation and serialization
• Check forward compatibility when designing schemas that must accept data from multiple client versions

Worth the install?

AI-flagged interpretation of the facts on this page. Verify before relying on it.

Install

jsoncompat on PyPI

Before you install

Medium install friction due to compiled wheels across multiple Python versions and platforms. Actively maintained with recent release history.

Requires Python 3.12 or later.

License in practice

License treatment is unclear; the description excerpt mentions MIT License but the fact sheet does not confirm SPDX or raw license metadata. Verify the actual license before use in proprietary or restricted contexts.

Quickstart

pip install jsoncompat==0.4.2

import jsoncompat as jsc

old_schema = '{"type": "string"}'
new_schema = '{"type": "number"}'
is_compatible = jsc.check_compat(old_schema, new_schema, jsc.Role.BOTH)
print(is_compatible)

Package facts

Evidence: jsoncompat-0.4.2-cp312-cp312-macosx_10_12_x86_64.whl; jsoncompat-0.4.2-cp312-cp312-macosx_11_0_arm64.whl; jsoncompat-0.4.2-cp312-cp312-manylinux_2_17_aarch64.manylinux2014_aarch64.whl; jsoncompat-0.4.2-cp312-cp312-manylinux_2_17_x86_64.manylinux2014_x86_64.whl; jsoncompat-0.4.2-cp312-cp312-musllinux_1_2_aarch64.whl; jsoncompat-0.4.2-cp312-cp312-musllinux_1_2_x86_64.whl; jsoncompat-0.4.2-cp312-cp312-win32.whl; jsoncompat-0.4.2-cp312-cp312-win_amd64.whl; jsoncompat-0.4.2-cp313-cp313-macosx_10_12_x86_64.whl; jsoncompat-0.4.2-cp313-cp313-macosx_11_0_arm64.whl; jsoncompat-0.4.2-cp313-cp313-manylinux_2_17_aarch64.manylinux2014_aarch64.whl; jsoncompat-0.4.2-cp313-cp313-manylinux_2_17_x86_64.manylinux2014_x86_64.whl; jsoncompat-0.4.2-cp313-cp313-musllinux_1_2_aarch64.whl; jsoncompat-0.4.2-cp313-cp313-musllinux_1_2_x86_64.whl; jsoncompat-0.4.2-cp313-cp313-win32.whl; jsoncompat-0.4.2-cp313-cp313-win_amd64.whl; jsoncompat-0.4.2-cp314-cp314-macosx_10_12_x86_64.whl; jsoncompat-0.4.2-cp314-cp314-macosx_11_0_arm64.whl; jsoncompat-0.4.2-cp314-cp314-manylinux_2_17_aarch64.manylinux2014_aarch64.whl; jsoncompat-0.4.2-cp314-cp314-manylinux_2_17_x86_64.manylinux2014_x86_64.whl

Tags

More Software Development packages

See also jsonschema-pydantic · dataclasses-jsonschema · jsonschema-pydantic-converter · trafaret · eido · kubernetes-validate · datamodel-code-generator · py-avro-schema · jsonalias · genson