hypothesis-jsonschema

A Hypothesis strategy for generating data that matches some JSON schema.

Here's the PyPI page.

API

The public API consists of just one function: hypothesis_jsonschema.from_schema, which takes a JSON schema and returns a strategy for allowed JSON objects.

Schema reuse with "definitions" and "$ref" is not yet supported, but everything else in drafts 04, 05, and 07 is fully tested and working.

For details on how to use this strategy in your tests, see the Hypothesis docs.

Supported versions

hypothesis-jsonschema requires Python 3.6 or later. In general, 0.x versions will require very recent versions of all dependencies because I don't want to deal with compatibility workarounds.

hypothesis-jsonschema may make backwards-incompatible changes at any time before version 1.x - that's what semver means! - but I've kept the API surface small enough that this should be avoidable. The main source of breaks will be if or when schema that never really worked turn into explicit errors instead of generating values that don't quite match.

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Changelog:

0.10.0 - 2019-12-26

• Improved handling of numeric schemas, especially integer schemas with multipleOf.
• Bump the minimum version of Hypothesis to ensure that all users have the unique array bugfix from 0.9.12.
• Fixed a bug where array schemas with an array of items, additionalItems: false, and a maxItems larger than the number of allowed items would resolve to an invalid strategy.

0.9.13 - 2019-12-18

• Improved internal handling of schemas for arrays which must always be length-zero.

0.9.12 - 2019-12-01

• Fixed RFC 3339 strings generation. Thanks to Dmitry Dygalo for the patch!
• Fixed a bug where equal floats and ints could be generated in a unique array, even though JSONSchema considers 0 === 0.0 (though this may also require an upstream fix to work...)

0.9.11 - 2019-11-30

• Fixed a bug where objects which could have either zero or one properties would always be generated with zero.

0.9.10 - 2019-11-27

• Updated project metadata and development tooling
• Supported and tested on Python 3.8

0.9.9 - 2019-10-02

• Correct handling of {"items": [...], "uniqueItems": true"} schemas

0.9.8 - 2019-08-24

• Corrected handling of the "format" keyword with unknown values - custom values are allowed by the spec and should be treated as annotations (i.e. ignored).

0.9.7 - 2019-08-15

• Improved canonicalisation, especially for deeply nested schemas.

0.9.6 - 2019-08-02

• A performance optimisation for null and boolean schema, which relies on a bugfix in jsonschema >= 3.0.2.

0.9.5 - 2019-08-02

• Improved handling of the contains keyword for arrays

0.9.4 - 2019-07-01

• Improved canonicalisation and merging for a wide range of schemas, which as usual unlocks significant optimisations and performance improvements for cases where they apply.

0.9.3 - 2019-06-13

• Future-proofed canonicalisation of type key.

0.9.2 - 2019-05-23

• Better internal canonicalization, which makes current and future optimisations more widely applicable.
• Yet another fix, this time for negative zero and numeric bouds as floats with sub-integer precision. IEEE 754 is tricky, even with Hypothesis!
• Fixes handling of enum with elements disallowed by base schema, handling of if-then-else with a base schema, and handling of regex patterns that are invalid in Python.

0.9.1 - 2019-05-22

• Fix the fix for numeric schemas with multipleOf and exclusive bounds.

0.9.0 - 2019-05-21

• Supports merging schemas for overlapping patternProperties, a significant performance improvement in most cases.
• If the "type" key is missing, it is now inferred from other keys rather than always defaulting to "object".
• Fixed handling of complicated numeric bounds.

0.8.2 - 2019-05-21

• Improve performance for object schemas where the min and max size can be further constrained from properties and propertyNames attributes.

0.8.1 - 2019-03-24

• Supports draft-04 schemata with the latest version of jsonschema

0.8.0 - 2019-03-23

• Further improved support for allOf, oneOf, and anyOf with base schemata
• Added support for dependencies
• Handles overlapping patternProperties

0.7.0 - 2019-03-21

• Now requires jsonschema >= 3.0
• Improved support for allOf, oneOf, and propertyNames
• Supports schemata with "type": [an array of types]
• Warning-free on Hypothesis 4.11

0.6.1 - 2019-02-23

• Fix continuous delivery configuration (before the latent bug manifested)

0.6.0 - 2019-02-23

• Support for conditional subschemata, i.e. the if, then, else keywords, and the anyOf, allOf, oneOf, and not keywords.

0.5.0 - 2019-02-22

• Works with jsonschema 3.0 pre-release
• Initial support for draft06 and draft07

0.4.2 - 2019-02-14

• Dropped dependency on canonicaljson
• Less warnings on Python 3.7

0.4.1 - 2019-02-06

• Relicensed under the more permissive Mozilla Public License, like Hypothesis
• Requires Hypothesis version 4.0 or later
• Fixed an array bounds bug with maxItems and contains keywords

0.4.0 - 2018-11-25

Supports string formats (email, datetime, etc) and simple use of the "contains" keyword for arrays.

0.3.0 - 2018-11-25

Good support for all basic types. MVP.

0.2.0 - 2018-11-24

Inference for null, boolean, string, and numeric types.

0.1.0 - 2018-11-21

Stake in the ground (generate arbitrary JSON and filter it!)

Security contact information

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