how to get request body in varnish

Question

I am currently working on a project based on varnish..

we write vcl and vmod. But the project needs to check the request body. How can I get the post request body in VCL or vmod with a C function?

Answer 1

You can do almost everything you want with VCL/VMOD. You should try to call a VMOD subroutine in vcl_recv, and then in C code, write something like below :

• Use VRT_GetHdr(rec->s, HDR_REQ, "\017Content-Length:"); to read the body length
• Use HTC_Read(rec->s->htc, body, bodylen);

And enjoy !

You should take a look at existing vmods https://www.varnish-cache.org/vmods, and be free to look into the varnish API sources.

Answer 2

I'm not sure you can.

Varnish generally only deals with Req/Resp headers. The bodies are passed along without (much) modification.

I you do find a solution please let me know as I'm interested in this as well.