$group = $module->getGroup();
$context = $this->getContext( $group, ResourceLoaderModule::TYPE_COMBINED );
- if ( $module->isKnownEmpty( $context ) ) {
- // Avoid needless request or embed for empty module
- $data['states'][$name] = 'ready';
- continue;
- }
+ $shouldEmbed = $module->shouldEmbedModule( $this->context );
- if ( $group === 'user' || $module->shouldEmbedModule( $this->context ) ) {
- // Call makeLoad() to decide how to load these, instead of
- // loading via mw.loader.load().
+ if ( ( $group === 'user' || $shouldEmbed ) && $module->isKnownEmpty( $context ) ) {
+ // This is a user-specific or embedded module, which means its output
+ // can be specific to the current page or user. As such, we can optimise
+ // the way we load it based on the current version of the module.
+ // Avoid needless embed for empty module, preset ready state.
+ $data['states'][$name] = 'ready';
+ } elseif ( $group === 'user' || $shouldEmbed ) {
// - For group=user: We need to provide a pre-generated load.php
// url to the client that has the 'user' and 'version' parameters
// filled in. Without this, the client would wrongly use the static
$group = $module->getGroup();
$context = $this->getContext( $group, ResourceLoaderModule::TYPE_STYLES );
- // Avoid needless request for empty module
- if ( !$module->isKnownEmpty( $context ) ) {
- if ( $module->shouldEmbedModule( $this->context ) ) {
- // Embed via style element
+ if ( $module->shouldEmbedModule( $this->context ) ) {
+ // Avoid needless embed for private embeds we know are empty.
+ // (Set "ready" state directly instead, which we do a few lines above.)
+ if ( !$module->isKnownEmpty( $context ) ) {
+ // Embed via <style> element
$data['embed']['styles'][] = $name;
- } else {
- // Load from load.php?only=styles via <link rel=stylesheet>
- $data['styles'][] = $name;
}
+ // For other style modules, always request them, regardless of whether they are
+ // currently known to be empty. Because:
+ // 1. Those modules are requested in batch, so there is no extra request overhead
+ // or extra HTML element to be avoided.
+ // 2. Checking isKnownEmpty for those can be expensive and slow down page view
+ // generation (T230260).
+ // 3. We don't want cached HTML to vary on the current state of a module.
+ // If the module becomes non-empty a few minutes later, it should start working
+ // on cached HTML without requiring a purge.
+ //
+ // But, user-specific modules:
+ // * ... are used on page views not publicly cached.
+ // * ... are in their own group and thus a require a request we can avoid
+ // * ... have known-empty status preloaded by ResourceLoader.
+ } elseif ( $group !== 'user' || !$module->isKnownEmpty( $context ) ) {
+ // Load from load.php?only=styles via <link rel=stylesheet>
+ $data['styles'][] = $name;
}
$deprecation = $module->getDeprecationInformation();
if ( $deprecation ) {