FoehnConfig

Core configuration class for Føhn. Like all other config classes, it can be auto-discovered via a foehn.config.php file. A legacy array-based approach via Kernel::boot() is also supported.

Signature

<?php

namespace Studiometa\Foehn\Config;

use Tempest\Core\DiscoveryCacheStrategy;

final readonly class FoehnConfig
{
    public function __construct(
        public DiscoveryCacheStrategy $discoveryCacheStrategy = DiscoveryCacheStrategy::NONE,
        public ?string $discoveryCachePath = null,
        /** @var list<class-string> */
        public array $hooks = [],
        public bool $debug = false,
    );

    public static function fromArray(array $config): self;
    public function isDebugEnabled(): bool;
    public function isDiscoveryCacheEnabled(): bool;
    public function getDiscoveryCachePath(): string;
}

Properties

Property	Type	Default	Description
discoveryCacheStrategy	DiscoveryCacheStrategy	NONE	Cache strategy for discoveries
discoveryCachePath	string|null	null	Custom path for cache files
hooks	class-string[]	[]	Opt-in hook classes to activate
debug	bool	WP_DEBUG value	Enable debug logging for discovery

Usage

Config file (recommended)

Create a config file in your app directory:

<?php
// app/foehn.config.php

use Studiometa\Foehn\Config\FoehnConfig;
use Studiometa\Foehn\Hooks\Cleanup\CleanHeadTags;
use Studiometa\Foehn\Hooks\Security\SecurityHeaders;
use Tempest\Core\DiscoveryCacheStrategy;

return new FoehnConfig(
    discoveryCacheStrategy: DiscoveryCacheStrategy::FULL,
    discoveryCachePath: WP_CONTENT_DIR . '/cache/foehn',
    hooks: [
        CleanHeadTags::class,
        SecurityHeaders::class,
    ],
    debug: WP_DEBUG,
);

Then boot the kernel without any config array:

Kernel::boot(__DIR__ . '/app');

Via Kernel::boot() (legacy)

You can also pass configuration directly to Kernel::boot():

use Studiometa\Foehn\Kernel;

Kernel::boot(__DIR__ . '/app', [
    'discovery_cache' => 'full',
    'discovery_cache_path' => WP_CONTENT_DIR . '/cache/foehn',
    'hooks' => [
        CleanHeadTags::class,
        SecurityHeaders::class,
    ],
    'debug' => WP_DEBUG,
]);

Note: If both a foehn.config.php file and boot array are provided, the config file takes precedence.

Discovery Cache Strategies

Strategy	Value	Description
NONE	'none'	No caching (default, for development)
FULL	'full'	Cache all discoveries (production)
PARTIAL	'partial'	Cache only vendor discoveries

Opt-in Hooks

Føhn includes built-in hook classes that you can opt into:

'hooks' => [
    \Studiometa\Foehn\Hooks\Cleanup\CleanHeadTags::class,
    \Studiometa\Foehn\Hooks\Cleanup\DisableEmoji::class,
    \Studiometa\Foehn\Hooks\Security\SecurityHeaders::class,
],

These classes are not auto-discovered — they must be explicitly listed.

Debug Mode

When enabled, discovery failures (reflection errors, missing classes) are logged via trigger_error():

'debug' => true,

Defaults to the value of WP_DEBUG when not explicitly set.

All Config Classes

All Føhn config classes follow the same pattern — discoverable via *.config.php files:

Config Class	Config file	Purpose
FoehnConfig	app/foehn.config.php	Core bootstrap settings
TimberConfig	app/timber.config.php	Template directories
AcfConfig	app/acf.config.php	ACF field transformation
RestConfig	app/rest.config.php	REST API permissions
RenderApiConfig	app/render-api.config.php	Render API allowlisting

Related

• Kernel
• Guide: Discovery Cache
• Guide: Configuration