[asterisk-dev] Proposing change to Queue and missed calls behavior

[Stian Hvatum]

On 12/07/2015 05:02 PM, Olle E. Johansson wrote:
>> On 07 Dec 2015, at 16:53, Mark Michelson <mmichelson at digium.com> wrote:
>>
>> On 12/04/2015 01:00 PM, Stian Hvatum wrote:
>>> Hi,
>>> I have a problem with an accompanying solution that I wish to share, but I am not sure if it is valuable enough or correct enough to be suggested as a patch to Asterisk.
>>>
>>> When SIP-phones are members of a queue, they tend to accumulate "missed calls" unless the C-flag is applied. When the C-flag is applied there is no missed calls at all, since all hangups are marked as "answered elsewhere". I have created and attached a patch which makes the C-flag "answer elsewhere" all hangups that are caused by app_queue canceling the dial or the call is really answered elsewhere, but sets normal cause when caller actually hangs up before the call is answered.
>>>
>>> I know the patch alters the behavior of the C-flag, and altering behavior of existing flags is probably a bad thing. I can try to create a new flag for this "missed call on caller hangup"-behavior if that is of any value. Also, I don't have much experience with the Asterisk source code, so if I break something by setting normal cause here I would be very happy if anyone would give me a hint about it. The only problem I have seen so far is that if the caller hangs up during an announcement or between app_queue's dial outs, the call is not marked as missed (as the previous call was "answered elsewhere" and no new calls went out to the phones).
>>>
>>> The code is running a few places without causing any trouble as far as I can tell. I wrote this after a customer had a few thousand missed calls on his queue-connected phone...
>>>
>>> Best regards and thanks for a great project!
>>> Stian Hvatum
>> In my opinion, if the c-flag is set and the caller hangs up, you are correct that the "answered elsewhere" status should not be applied. I also think the "answered elsewhere" status should not be applied if a call to a single queue member times out before the member answers the call. The c-flag behavior should only be applied when multiple queue members' phones are ringing at the same time, and Asterisk has to cancel the outgoing call to certain members due to the call being answered by someone else.
>>
>> I think the change you are suggesting would be welcome.
> Mark,
> That was not the idea when I wrote it. (If I remember correctly). The case was that the phone should NEVER show any queue calls as missed, regardless of why.
>
> This behaviour is still useful - to separate personal calls that require callback from calls that doesn’t require call back (i.e. calls from the queue).
>
> I like the idea with a new option.
>
> /O

Thanks for comments.
As Olle writes, there are many cases where a call never should be shown 
as missed. I think it might be better to implement a new option, then it 
at least won't hurt any one relying on the current behavior. Are there 
any naming schemes for these options, or can I use e.g. "M" for "only 
show call as Misse when first caller in line hangs up"?

If I want to commit this as a new option upstream, should I also write 
some sort of unit test or regression test?

Best regards,
Stian Hvatum