`StaticCache::canPurge()`

Whether the CDN driver can purge. false when it has no credentials (headers-only mode).

php

if (! StaticCache::canPurge()) {
    // pages expire by TTL only
}

Reference

php

StaticCache::canPurge(): bool

Good to know

In headers-only mode, purgeTags(), purgeUrls(), purgePrefix() and purgeAll() do nothing and log a notice.