Installation

Schemable Validator ships as three independent packages: a PHP core library, a WordPress plugin, and a TypeScript client. Install only the packages you need.

Requirements

	Version	Purpose
PHP	^7.4 || ^8.x	Core library & WP plugin
WordPress	5.9+	WP plugin only
Node.js	>=22.12.0	@uuki/schemable-validator-client only

PHP library

composer require uuki/schemable-validator

WordPress plugin

Clone the repository, place it in your plugins directory, and install the dependencies.

# Clone the repository
git clone https://github.com/uuki/schemable-validator.git
# Example destination: wp-content/plugins/schemable-validator

# Navigate to the WordPress package inside the plugin and install dependencies
cd path/to/plugins/schemable-validator/packages/wp-schemable-validator
# If placed under `wp-content`: wp-content/plugins/schemable-validator/packages/wp-schemable-validator

composer install --no-dev

Activate Schemable Validator from the plugin list in the WordPress admin dashboard.

What's included

Core classes

After installing via composer require, the classes under the SchemableValidator\ namespace become available.

Class	Namespace	Description
Validator	Orchestration	Validates input values against a schema
SchemaBuilder	Orchestration	Assembles field schemas and converts them to Validator format or JSON Schema
Template	Orchestration	Injects validated data into template strings
SV	(root)	Facade for SchemaBuilder. Build schemas with SV::object(), SV::string(), etc.
CsrfGuard	Security	CSRF token generation and verification
FormController	Infrastructure	Persists validated data across multi-page forms using sessions
MessageDict	I18n	Defines error messages per field and rule (i18n)
NativeFileValidator	Adapters\Native	Dependency-free file MIME validation (default)
NativeImageDriver	Adapters\Native	Image dimension and size constraint checks

INFO

The default engine (NativeAdapter) works without any external validation library. respect/validation and opis/json-schema are optional (suggest) dependencies.

See Feature Guide and SchemaBuilder for details.

WordPress helper functions

Once the plugin is activated, the following schv_* functions become available globally.

Function	Return	Description
schv_validator($schema, $config)	Validator	Creates a Validator instance with optional config (adapter, drivers, dict)
schv_csrf()	CsrfGuard	Creates a CSRF token manager
schv_message_dict()	MessageDict	Returns the site-wide dictionary via the schv_message_dict filter
schv_form()	FormController	Manages session state for multi-page forms
schv_template($options)	Template	Injects data into a WP option template
schv_register_schema($route, $provider)	void	Registers a schema as a REST endpoint
schv_schema_url($route)	string	Returns the REST URL of a registered schema

See Feature Guide and Interfaces for details.

Package layout

packages/
  core/                              # Core library (framework-agnostic)
    SV.php                           # Facade
    constants.php

    Orchestration/
      Validator.php                  # Validation orchestrator
      SchemaBuilder.php              # Schema definition → Validator / JSON Schema
      Template.php                   # Template string interpolation

    Schema/                          # Schema definition layer
      AbstractFieldSchema.php
      StringSchema.php
      IntegerSchema.php, NumberSchema.php
      BooleanSchema.php, EnumSchema.php
      ArraySchema.php, FileSchema.php
      CustomFieldSchema.php
      RuleMapper.php

    Validation/                      # Interfaces + pure logic (no external deps)
      BackendAdapter.php             # Adapter interface
      ExecutableValidator.php        # Per-field executor interface
      CaptchaDriver.php             # CAPTCHA verification interface
      FileValidationDriver.php      # File validation interface
      ImageDriver.php               # Image constraint interface
      CustomField.php               # Escape-hatch field interface
      Coercion.php, Formats.php     # Coercion Contract & format definitions
      CalendarDate.php, JsonLogicEval.php
      Transform.php, MessageResolver.php

    Adapters/                        # Swappable implementations
      Native/                        # Default (zero external deps)
        NativeAdapter.php
        NativeExecutableValidator.php
        NativeFileValidator.php
        NativeImageDriver.php
      Respect/                       # Optional (respect/validation)
        RespectAdapter.php
        RespectExecutableValidator.php
        RespectRules.php
        Rules/                       # Respect AbstractRule extensions
      Opis/                          # Optional (opis/json-schema)
        OpisAdapter.php
        OpisExecutableValidator.php
      Captcha/                       # CAPTCHA provider drivers
        AbstractCaptchaDriver.php
        ReCaptchaV3Driver.php
        HCaptchaDriver.php
        TurnstileDriver.php
        NullCaptchaDriver.php

    Infrastructure/
      CurlController.php             # SSRF-guarded HTTPS client
      FormController.php             # Session-based form state

    I18n/
      MessageDict.php
      DefaultMessages.php
      Locales/                       # Locale message files

    Security/
      CsrfGuard.php                  # CSRF token management

  wp-schemable-validator/            # WordPress plugin
    index.php                        # Plugin bootstrap
    composer.json                    # Requires core via composer path repo
    src/Interfaces/WordPress/
      Plugin.php                     # Admin screen & settings
      helpers.php                    # schv_* global functions
    examples/                        # Sample shortcodes (local dev)

INFO

respect/validation and opis/json-schema are optional (suggest) dependencies. The default engine (NativeAdapter) works without any external validation library.