EASY_SVG_API

Constant · Easy SVG · Status: Stable

EASY_SVG_API is a plain number that tells add-ons which version of Easy SVG's sanitizer contract is installed. The contract is one function, easy_svg_sanitizer(), which returns a sanitizer set up exactly the way the site cleans SVG. When the constant exists, you can use that function. Since 5.0.0.

Usage

define( 'EASY_SVG_API', 3 );

Defined in easy-svg.php, at the moment the plugin file loads. Read it with defined( 'EASY_SVG_API' ) and compare it as an integer.

When to use it

• Your plugin or theme cleans SVG markup and should use the same rules as the site (the allow-list from esw_svg_allowed_tags and esw_svg_allowed_attributes, and the remote reference setting).
• You want to know whether Easy SVG is installed and offers that function, without comparing plugin versions.

Do not use it when:

• You need the Icons panel extension points. That is EASY_SVG_PANEL_API.
• You need the icon write functions or easy_svg_registrable_icons. That is EASY_SVG_ICONS_API.

Parameters

None: this is a constant, not a function.

Return value

Default

Not applicable: the constant is defined by the plugin and is missing when Easy SVG is not active.

Examples

Clean markup the way the site does

function myaddon_clean_svg( $markup ) {
	if ( ! defined( 'EASY_SVG_API' ) || EASY_SVG_API < 3 ) {
		return false;
	}

	$sanitizer = easy_svg_sanitizer();
	if ( null === $sanitizer ) {
		return false; // The sanitizing library is not loaded.
	}

	$clean = $sanitizer->sanitize( (string) $markup );

	return is_string( $clean ) && '' !== trim( $clean ) ? $clean : false;
}

Check once, after all plugins have loaded

Whether EASY_SVG_API exists while your own plugin file loads depends on load order. Decide on plugins_loaded.

function myaddon_maybe_boot() {
	if ( ! defined( 'EASY_SVG_API' ) ) {
		add_action( 'admin_notices', 'myaddon_missing_easy_svg_notice' );
		return;
	}

	require_once __DIR__ . '/includes/svg-features.php';
}
add_action( 'plugins_loaded', 'myaddon_maybe_boot' );

function myaddon_missing_easy_svg_notice() {
	if ( ! current_user_can( 'activate_plugins' ) ) {
		return;
	}
	printf(
		'<div class="notice notice-warning"><p>%s</p></div>',
		esc_html__( 'My Add-on needs Easy SVG Support to be active.', 'myaddon' )
	);
}

Defensive: constant and function

$myaddon_can_sanitize = defined( 'EASY_SVG_API' ) && function_exists( 'easy_svg_sanitizer' );

How it works

• define( 'EASY_SVG_API', 3 ) runs at the top of easy-svg.php, right after the two allow-list classes and before any settings are read. Once Easy SVG has loaded, the constant exists on every request: front end, admin, REST, cron and WP-CLI.
• It is defined whether or not SVG uploads or the icon library are switched on. It says that the code is there, not that a feature is enabled.
• easy_svg_sanitizer() returns a new sanitizer on every call, configured with the filtered allow-lists and esw_svg_remove_remote_references. It returns null when the sanitizing library is not available.
• WordPress loads active plugins in the order of their file paths. A plugin in a folder that sorts before easy-svg (for example easy-svg-pro, because - sorts before /) and all must-use plugins load earlier, so the constant is not there yet while their main file runs.

Pitfalls

• Checking too early. At the top of your plugin file the constant can be missing even though Easy SVG is active. Check on plugins_loaded or later.
• Comparing plugin versions instead. The readme promises this number, not version strings.
• Assuming easy_svg_sanitizer() returns an object. It can return null. Always check before calling sanitize().
• Using the classes behind it. esw_svg_tags, esw_svg_attributes and the global $sanitizer are internal. A rename makes class_exists() false and your add-on would think Easy SVG is missing.

Related

• easy_svg_sanitizer()
• EASY_SVG_PANEL_API
• EASY_SVG_ICONS_API
• esw_svg_allowed_tags
• esw_svg_remove_remote_references