Schema Validation

Overview

The library includes a built-in JSON Schema subset validator for validating handler parameters. It is optional — normal parameter binding works without it.

Enabling schema validation

'validation' => [
    'strict' => true,
    'schema' => ['enabled' => true],
],

Defining schemas on handlers

Implement RpcSchemaProviderInterface:

use Lumen\JsonRpc\Validation\RpcSchemaProviderInterface;

final class Product implements RpcSchemaProviderInterface
{
    public static function rpcValidationSchemas(): array
    {
        return [
            'create' => [
                'type'       => 'object',
                'required'   => ['name', 'price'],
                'properties' => [
                    'name'  => ['type' => 'string', 'minLength' => 1],
                    'price' => ['type' => 'number'],
                ],
                'additionalProperties' => false,
            ],
        ];
    }
}

Supported JSON Schema keywords

Keyword	Status	Notes
`type`	Supported	string, integer/int, number, boolean/bool, array, object, null
`required`	Supported
`properties`	Supported	Nested validation
`additionalProperties`	Supported	Boolean or schema
`items`	Supported	Array item validation
`minItems` / `maxItems`	Supported
`uniqueItems`	Supported
`minLength` / `maxLength`	Supported
`pattern`	Supported	Regex patterns
`minimum` / `maximum`	Supported	Inclusive bounds
`exclusiveMinimum` / `exclusiveMaximum`	Supported	Exclusive bounds
`enum`	Supported
`const`	Supported
`allOf` / `anyOf` / `oneOf`	Supported	Composition
`not`	Supported
`minProperties` / `maxProperties`	Supported
`format`	Partial	See supported formats below

Supported `format` values

Format	Description
`email`	Email address (RFC 5322 subset)
`uri`	URI with scheme
`url`	HTTP/HTTPS URL
`uuid`	UUID (any version, case-insensitive)
`ipv4`	IPv4 address
`ipv6`	IPv6 address
`date-time`	ISO 8601 date-time (requires timezone)
`date`	ISO 8601 date (YYYY-MM-DD)
`time`	ISO 8601 time (HH:MM:SS)

Unknown format values are silently ignored (not validated).

Intentionally unsupported

$ref — schema references
if/then/else — conditional schemas
dependencies / dependentSchemas
prefixItems / tuple validation
contentEncoding / contentMediaType
Numeric multipleOf
patternProperties
format values beyond the list above

These are omitted to keep the validator simple, deterministic, and suitable for runtime parameter validation without external dependencies.

Max depth protection

Nested schema validation is capped at 32 levels to prevent stack overflow from deeply nested schemas.