Reading SIP headers on REFER packet

Hi all,

I’m trying to read a SIP header from a REFER packet, here’s the packet:

REFER sip:redacted;transport=ws SIP/2.0
Via: SIP/2.0/WSS 8eqih34l1f85.invalid;received=redacted;branch=z9hG4bK3848701
Max-Forwards: 69
To: redacted;tag=dc0472c5-34a8-4fd1-abe6-6f771eca5ddf
From: sip:redacted;tag=0aaqq26p7v
Call-ID: 56c69406-5502-4771-85b3-e629085a3da1
CSeq: 6549 REFER
X-Redirect: pause
X-Foo: Bar
Refer-To: sip:pause@redacted:8089
Referred-By: sip:redacted
Contact: sip:i9pivj14@8eqih34l1f85.invalid;transport=ws
Allow: INVITE, ACK, CANCEL, BYE, UPDATE, MESSAGE, OPTIONS, REFER, INFO, NOTIFY
Supported: outbound
User-Agent: Redacted
Content-Length: 0
Content-Length: 0

Using the following:

[pause]
exten => s,1,Set(FOO=${PJSIP_HEADER(read,X-Foo)})
exten => s,n,NoOp( *** ${FOO} *** )

The variable FOO always reports empty. This works on invites, for some reason struggling with refers.

Any help appreciated! Might be doing something boneheaded here dunno.

BK

Looks like it’s not possible at least in 20.x.