External services: create healthcheck APIs so that systems can gracefully degrade
Description
For example, a site might want to do:
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if ( $isDown( "elasticsearch" ) ) {
showError( "Hey, our search isn't working right now, please check back soon!" );
} else {
results = search( ... );
// ...
}In the case, above, the $isDown() call does not check elasticsearch directly. Instead, it just checks with the latest run healthcheck to avoid multiple requests all slowing down and crashing trying to ping a service that has died.
