json_payload_validator 0.1.1

JSON validator package based on jsonschema that returns nicer validation errors for end users

Little Python package that formats validation error messages from jsonschema. You should use this package if you want a stand alone json validator decoupled from any framework.

Reason of being

jsonschema is really cool but its validation error messages suck as they’re meant for developers, not end users. So if you have an API that uses jsonschema to validate json payloads and want to return nicer error messages to your end users you can use this package :)

How it works

3 simple rules:

• If you don’t send a required property in the payload you’ll get the message 'foo' is a required property.

• If validation fails the validation rule will be returned Validation of property 'foo' failed: {'minLength': 2, 'type': 'string', 'maxLength': 50}.

• If you add message property in a validation rule its value will be returned instead of the rule Validation of property 'foo' failed: Custom error message.

Usage

Successful validation example

from json_payload_validator import validate

schema = {
    'type': 'object',
    'properties': {
        'name': {'type': 'string', 'minLength': 2, 'maxLength': 50},
    },
    'required': [
        'name'
    ]
}

payload = {'name': 'John Maus'}

error = validate(payload, schema)
print(error) # None

Validation failure example

from json_payload_validator import validate

schema = {
    'type': 'object',
    'properties': {
        'name': {'type': 'string', {'minLength': 2, 'type': 'string', 'maxLength': 50}},
    },
    'required': [
        'name'
    ]
}

payload = {'name': 555}

error = validate(payload, schema)
print(error) # Validation of property 'name' failed: {'minLength': 2, 'type': 'string', 'maxLength': 50}

Custom error message example

from json_payload_validator import validate

schema = {
    'type': 'object',
    'properties': {
        'name': {'type': 'string', 'message': 'Name must be a string'},
    },
    'required': [
        'name'
    ]
}

# example of validation
payload = {'name': 555}

error = validate(payload, schema)
print(error) # Validation of property 'name' failed: Name must be a string