Use properties defaults

[jcollado]

When using a schema that has some default values for properties, the validation
passes when those properties are missing.

That's completely fine, but I'd expect also that when a property is missing,
the data passed to the validator is overwritten to set the property to the
default value according to the schema.

For example:

>>> schema = {'type': 'object',
              'properties': {
              'answer': {'type': 'integer', 'default': 42},
              },
             }
>>> data = {}
>>> jsonschema.validate(data, schema)
>>> print data
{}

What I'd expect is:

>>> print data
{'answer': 42}

I realize that if the schema type doesn't match a mutable type, this won't work
because the jsonschema.validate won't be able to modify the data in place. In such a
case, maybe a change in the API so that it returns the new data would be fine:

>>> schema = {'type': 'integer',
              'default': 42,
             }
>>> new_data = jsonschema.validate(0, schema)
>>> print new_data
42

[Julian]

Hi!

This is a duplicate of #4, you can check that out for one or two examples of some code that does this. The JSON Schema specification doesn't specify that the default property should do this, and by default, IMHO, it shouldn't :). Since it's relatively easy to do this yourself (see there), I think that should be good. Let me know if that works for you.

Julian.

[jcollado]

@Julian Thanks for the reference to issue #4. Yes, that fixes my problem indeed.

[Julian]

Glad to hear it :)! Thanks.