Front Controller Configuration

Description

Front controller behaviour can be configured using configuration options. Pre PHP 7.4 there was a 20% penalty of doing this vs editing the index.php file. However, PHP preloading[fn:preloading] negates this. Post PHP 7.4 configuration options can be used without a performance penalty.

Syntax

config/packages/framework.yaml

framework:
# use the HTTP Cache defaults
http_cache: true

# configure every HTTP Cache option
http_cache:
    private_headers: ['Authorization', 'Cookie', 'MyCustomHeader']
    default_ttl: 3600
    allow_revalidate: true
    stale_if_error: 600

# configure proxies to trust directly in the config file:
trusted_proxies: '127.0.0.0/8,10.0.0.0/8,172.16.0.0/12,192.168.0.0/16'
# or use an env var if this value is dynamic
trusted_proxies: '%env(TRUSTED_PROXIES)%'

# you can also define the trusted headers
trusted_headers: ['x-forwarded-all', '!x-forwarded-host', '!x-forwarded-prefix']

Footnotes

[fn:preloading]https://www.php.net/manual/en/opcache.preloading.php