GetHttpRequestData(): Performance gotcha

GetHTTPRequestData() is a built in CFML function that retrieves:

• HTTP Headers
• HTTP Method
• HTTP Body

Handy! However, the HTTP Body part has issues. Ben Nadel blogged about one such issue here: https://www.bennadel.com/blog/2824-gethttprequestdata-may-break-your-request-in-coldfusion-but-gethttprequestdata-false-may-not.htm.

I discovered another issue today. Each time you call GetHttpRequestData(), Lucee will re-read the input stream of the request to populate the body, consuming memory in the process.

This won’t necessarily show up with some cursory testing of request times. However, if you use something like FusionReactor to test the amount of memory a request burns through you are likely to see some unexpectedly large requests when:

• The request body is large (i.e. file uploads, big API payloads)
• You call GetHttpRequestData() multiple times.

The solution, as Ben points out, is to use GetHttpRequestData( false ) if you do not care about the request body.

I have raised an issue with the Lucee team to look into only reading the stream once: https://luceeserver.atlassian.net/browse/LDEV-3176.