[Kamailio-Users] [sr-dev] rfc: xavp - extended avp

[Daniel-Constantin Mierla]

On 29.07.2009 11:52 Uhr, Martin Hoffmann wrote:
> Daniel-Constantin Mierla wrote:
>   
>> On 28.07.2009 13:51 Uhr, Martin Hoffmann wrote:
>>     
>>> You could generalize this into only using the generic data value and
>>> wrap the other types into these. This requires makeing these generic
>>> data values in the script language somehow. For all this, you will need
>>> a somewhat more elaborate interface to the type than a free function.
>>>   
>>>       
>> it is an option, but I wanted to have it simple for common data types in  
>> the same time to allow dealing with more complex structures.
>>     
>
> Agree. I was actually more thinking into the future and into a Grand
> Unified Variable kind of thing. Not sure if this should be a service
> provided by the core or some module. But should we agree that we want
> such a thing then it might be better to work on that instead of building
> an interims solution based on AVPs.
>
> This is not to diminish your work in any way, I quite like the
> possibilities especially with the option for lists. It just may safe you
> same work that will eventually be superseded by something else.
>   
the core has to provide at least the mechanisms to hook up to different 
contexts (e.g., like now to sip message/transaction). The PV interface 
implementation is done in pv module, so that is not bound to core at 
all. Without pv module, xavp cannot be used from config.

To the other matter, I brought this to discussion to find the best 
solution, therefore all is open. There is no memory penalty as the value 
is a union, if one uses only the generic data it is not affected by the 
existence of the other simple data types.

I am not a fan of over-engineering, trying to keep being practical, not 
getting to something very complex due to nature of variables existing 
now, in kamailio (at least) there are references inside the sip message, 
to the proxy and OS environment, to shared and private memory, list of 
values in share memory (avps), database query result, hash table (local 
cache), memcached data (distributed cache). What is common to all these 
is the interface to config file -- each exports set/get function to/from 
int or str values.

Cheers,
Daniel

-- 
Daniel-Constantin Mierla
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