JSON Schema - require all properties

I do this in code with a one-liner, for instance, if I want to use required for insert in a DB, but only want to validate against the schema when performing an update.

prepareSchema(action) {
    const actionSchema = R.clone(schema)
    switch (action) {
        case 'insert':
            actionSchema.$id = `/${schema.$id}-Insert`
            actionSchema.required = Object.keys(schema.properties)
            return actionSchema
        default:
            return schema
    }
}

I doubt there exists a way to specify required properties other than explicitly name them in required array.

But if you encounter this issue very often I would suggest you to write a small script that post-process your json-schema and add automatically the required array for all defined objects.

The script just need to traverse the json-schema tree, and at each level, if a "properties" keyword is found, add a "required" keyword with all defined keys contained in properties at the same level.

Let the machines do the bore stuff.


You can just use the "minProperties" property instead of explicity naming all the fields.

{
    "type": "object",
    "properties": {
        "elephant": {"type": "string"},
        "giraffe": {"type": "string"},
        "polarBear": {"type": "string"}
    },
    "additionalProperties": false,
    "minProperties": 3
}

if you using the library jsonschema in python use custom validators:

first create custom validator:

# Custom validator for requiring all properties listed in the instance to be in the 'required' list of the instance
def allRequired(validator, allRequired, instance, schema):
    if not validator.is_type(instance, "object"):
        return
    if allRequired and "required" in instance:
        # requiring all properties to 'required'
        instanceRequired = instance["required"]
        instanceProperties = list(instance["properties"].keys())
        for property in instanceProperties:
            if property not in instanceRequired:
                yield ValidationError("%r should be required but only the following are required: %r" % (property, instanceRequired))
        for property in instanceRequired:
            if property not in instanceProperties:
                yield ValidationError("%r should be in properties but only the following are properties: %r" % (property, instanceProperties))

then extend an exsitsing validator:

all_validators = dict(Draft4Validator.VALIDATORS)
all_validators['allRequired'] = allRequired

customValidator = jsonschema.validators.extend(
    validator=Draft4Validator,
    validators=all_validators
)

now test:

schema =  {"allRequired": True}
instance = {"properties": {"name": {"type": "string"}}, "required": []}
v = customValidator(schema)
errors = validateInstance(v, instance)

you will get the error: 'name' should be required but only the following are required: []

Tags:

Jsonschema