Validation rules reference

Each Draft 7 keyword is implemented as a separate rule class under Source\Schema\Validators\. This page lists every keyword and its implementation unit.

Type keywords

Keyword	Implementation unit
type	JsonFlow.ValidationRules.Types
enum	JsonFlow.ValidationRules.Enum
const	JsonFlow.ValidationRules.Consts

String keywords

Keyword	Implementation unit
minLength	JsonFlow.ValidationRules.MinLength
maxLength	JsonFlow.ValidationRules.MaxLength
pattern	JsonFlow.ValidationRules.Pattern
format	JsonFlow.ValidationRules.Format

Number keywords

Keyword	Implementation unit
minimum	JsonFlow.ValidationRules.Minimum
maximum	JsonFlow.ValidationRules.Maximum
exclusiveMinimum	JsonFlow.ValidationRules.ExclusiveMinimum
exclusiveMaximum	JsonFlow.ValidationRules.ExclusiveMaximum
multipleOf	JsonFlow.ValidationRules.MultipleOf

Array keywords

Keyword	Implementation unit
items	JsonFlow.ValidationRules.Items
minItems	JsonFlow.ValidationRules.MinItems
maxItems	JsonFlow.ValidationRules.MaxItems
uniqueItems	JsonFlow.ValidationRules.UniqueItems
contains	JsonFlow.ValidationRules.Contains

Object keywords

Keyword	Implementation unit
properties	JsonFlow.ValidationRules.Properties
required	JsonFlow.ValidationRules.Required
additionalProperties	JsonFlow.ValidationRules.AdditionalProperties
patternProperties	JsonFlow.ValidationRules.PatternProperties
propertyNames	JsonFlow.ValidationRules.PropertyNames
minProperties	JsonFlow.ValidationRules.MinProperties
maxProperties	JsonFlow.ValidationRules.MaxProperties

Composition keywords

Keyword	Implementation unit
allOf	JsonFlow.ValidationRules.AllOf
anyOf	JsonFlow.ValidationRules.AnyOf
oneOf	JsonFlow.ValidationRules.OneOf
not	JsonFlow.ValidationRules.NotRule
if / then / else	JsonFlow.ValidationRules.Conditional

Reference

Keyword	Implementation unit
$ref	JsonFlow.ValidationRules.Ref

Format validators

All format validators extend TBaseFormatValidator (unit JsonFlow.FormatValidators.Base). They are registered in JsonFlow.FormatRegistry.

Format string	Class unit
date	JsonFlow.FormatValidators.Date
date-time	JsonFlow.FormatValidators.DateTime
time	JsonFlow.FormatValidators.Time
email	JsonFlow.FormatValidators.Email
ipv4	JsonFlow.FormatValidators.Ipv4
ipv6	JsonFlow.FormatValidators.Ipv6
uri	JsonFlow.FormatValidators.Uri
uuid	JsonFlow.FormatValidators.Uuid
cpf	JsonFlow.FormatValidators.CPF
cnpj	JsonFlow.FormatValidators.CNPJ
cep	JsonFlow.FormatValidators.CEP
phone-br	JsonFlow.FormatValidators.BrazilianPhone
license-plate-br	JsonFlow.FormatValidators.BrazilianLicensePlate

Base rule interfaces

Every validation rule must implement IJSONSchemaTrait:

IJSONSchemaTrait = interface
  procedure Parse(const ANode: IJSONObject);   // extract keyword params from schema
  procedure SetNode(const ANode: TSchemaNode); // set owning schema node
  function Validate(const ANode: IJSONElement; const APath: String;
    var AErrors: TList<TValidationError>): Boolean;
end;

The abstract base TBaseValidationRule (unit JsonFlow.ValidationRules.Base) provides the common AddError helper and rule type classification (TRuleType):

Value	Meaning
rtPrimitive	Validates a single keyword (e.g., minLength)
rtComposite	Combines multiple sub-schemas (e.g., allOf)
rtStructural	Structural constraint (e.g., properties)

Registering a custom format validator

uses
  JsonFlow.FormatRegistry;

// Implement your validator
type
  TMyFormatValidator = class(TBaseFormatValidator)
    function Validate(const AValue: string): Boolean; override;
    function FormatName: string; override;
  end;

// Register at startup — RegisterValidator is a class method; Instance is available
// but registration goes directly through the class method:
TFormatRegistry.RegisterValidator('my-format', TMyFormatValidator.Create);

TFormatRegistry.RegisterValidator is a class (static) method — it does not require calling .Instance first. The registry dictionary is class-level. Other class methods: UnregisterValidator, GetValidator, IsFormatRegistered, GetRegisteredFormats, ClearRegistry.