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Pseudovariable implementation extended
The pseudovariable implementation has been extended with new operations to give more power to the script writer:
1. Added 2 new operations on pseudovariables values from the script:
- delete the pseudovariable at a certain index; syntax: pvar[_index_]=NULL.
- overwrite the value of a pseudovariable at a certain index; syntax: pvar[_index_]=_value_.
Ex: $(avp(i:10)[1])=NULL.
2. Added one new function for avp: inserts a value to an avp set at a certain position
3. Added operations for set values of pseudovariables:
- count the number of values; syntax: set_count(_pvar_name_).
- select an element from the set based on fitness. The selection algorithm is the genetic algorithm roulette-wheel selection. One usage example is selecting a route based on costs. syntax: set_select_weight(_pvar_name_); it returns the index of the selected value.
4. Added a new transformation: extract a parameter from a To like header
- syntax: {nameaddr.param,param_name}
- example: "test" <sip:test@opensips.org>;tag=dat43h' {nameaddr.param,tag} = dat43h
5. Added context meaning to pseudovariables - a new token added in front of the pv type name that specifies the context where the pv should be taken from
The implementation is made general - with a mechanism of registering pv context functions, allowing for extensions and addition of custom contexts. For now there are 2 pv contexts: reply and request, registered by the tm module.
- example:
- referencing $(<request>ru) from a reply route will get the Request-URI from the request
- the <reply> context can be used from failure route to access information from the reply.