jsonschema_test.py

# Rough sketch of using hypothesis to make jsonschema schemas

from hypothesis.strategies import (
    composite, dictionaries, fixed_dictionaries, sampled_from, text
)

JSON_SCHEMA_PRIMITIVES = ('array', 'boolean', 'integer', 'number', 'null',
                          'object', 'string')
MAX_SCHEMA_DEPTH = 2


@composite
def make_props_strategy(
        draw,
        key_st=text(min_size=2, max_size=5),
        value_st=fixed_dictionaries({'type': sampled_from(JSON_SCHEMA_PRIMITIVES)}),
        depth=0):
    props = draw(dictionaries(key_st, value_st, max_size=4))
    for key, prop in props.items():
        if prop['type'] == 'object':
            if depth > MAX_SCHEMA_DEPTH:
                del props[key]
                continue
            prop['properties'] = draw(make_props_strategy(key_st, value_st, depth+1))
    return props


@composite
def make_jsonschema(draw):
    node = {
        'type': 'object',
        'properties': draw(make_props_strategy()),
        }
    return node

from hypothesis import find
from pprint import pprint
pprint(make_jsonschema().filter(lambda x: True in [z['type'] == 'object' for y,z in x['properties'].items()]).example())

stdout.txt

{'properties': {u'\x05\u0120\x98\u019b\x9c': {'type': 'array'},
                u'\x98\u019b': {'properties': {u'\x08\x03': {'type': 'number'},
                                               u'\x08\x11\x86': {'properties': {u'\x11\ucb4f': {'type': 'integer'},
                                                                                u'D\x85': {'type': 'integer'},
                                                                                u'\xbcP': {'type': 'integer'},
                                                                                u'\u0133\x85': {'type': 'integer'}},
                                                                 'type': 'object'},
                                               u'\x08\x9e': {'type': 'null'}},
                                'type': 'object'},
                u'\u0120\t\u019b\x13\x9c': {'type': 'array'},
                u'\u0120\x98\x13\t\x13': {'type': 'integer'}},
 'type': 'object'}