reqId unique request identifier
Returns a single property named
catalogRecord.exists. The property value is set to “1” if the specified catalog entry exists in the image or default catalog, otherwise it is set to “0”.
req=exists requests against the
/is/content context will indicate the presence or absence of a specified record in the static content catalog.
Other commands in the request string are ignored. The HTTP response is cacheable with the TTL based on
Requests that support JSONP response format lets you specify the name of the JS callback handler using the extended syntax of
req=...,json [&handler = reqHandler ]
<reqHandler> is the name of the JS handler that is present in the JSONP response. Only a-z, A-Z, and 0-9 characters are allowed. Optional. Default is