[asterisk-dev] Problem with PJSIP and Blind Transfers

[Joshua Colp]

On Thu, Apr 20, 2017, at 03:34 PM, Dan Cropp wrote:

<snip>

> 
> 
> With PJSIP, it seems as though the success/failure of the Transfer dial
> plan command occurs when it sends the REFER.  It never waits to know if
> it succeeds or fails.
> Looking at the PJSIP messages, this TRANSFERSTATUS is sent even before
> the other side has responded with the 202 Accepted packet.

This is correct. TRANSFERSTATUS only reflects our ability to send the
message currently, not the actual response of the other side.

> 
> When logging the PJSIP messages, I see the so valid number case sends the
> REFER, receives 202 Accepted, but the trace doesn't write the Notify/OK
> response with the Verbosity and PJSIP debug enabled.

It would be up to the other side to send the NOTIFY, and PJSIP itself
may actually request that the implicit subscription (which generates the
NOTIFY) not occur. This would explain why you don't see the NOTIFY.

> 
> For failures, I do not even see the 404 Not Found in the log.  Asterisk
> replies with a TRANSFERSTATUS of SUCCESS when the other end sends the 404
> Not Found.
> 
> Is the correct next step to submit an Issue?

Yes, depending on the level of interaction we have it may be possible to
make things reflect reality better. We use PJSIP functionality to do
this REFER functionality so we have to see what it can do.

Cheers,

-- 
Joshua Colp
Digium, Inc. | Senior Software Developer
445 Jan Davis Drive NW - Huntsville, AL 35806 - US
Check us out at: www.digium.com & www.asterisk.org