Extend routing specification to allow inserting arbitrary

pre-call-originate ("po_proc") routine to do various
conditioning, such is in this case appending arbitrary
attributes into accounting request. 3 such functions are
provided:

- VAL2Xattrs: append to both originate and answering accounting
  requests;
- VAL2XattrsO: append to originate request only;
- VAL2XattrsA: append to answering request only.

PR: #38

sippy/B2BRoute.py

@@ -26,6 +26,7 @@
 
 from sippy.SipHeader import SipHeader
 from sippy.SipConf import SipConf
+from sippy.B2BTransforms import getTransProc
 
 try:
     from urllib import unquote
@@ -163,6 +164,8 @@ def __init__(self, sroute = None, cself = None):
                     self.params['outbound_proxy'] = (v, 5060)
                 else:
                     self.params['outbound_proxy'] = (host_port[0], int(host_port[1]))
+            elif a == 'po_proc':
+                self.params['po_proc'] = getTransProc(v)
             else:
                 self.params[a] = v
         if len(extra_headers) > 0:

sippy/B2BTransforms.py

@@ -26,6 +26,7 @@
 import sys
 
 from sippy.SipRequest import SipRequest
+from sippy.CCEvents import CCEventTry
 
 class HDR2Xattrs():
     # Source: https://github.com/sippy/b2bua/pull/38
@@ -55,10 +56,34 @@ def __call__(self, cc:'CallController', req:SipRequest):
         else:
             cc.extra_attributes.extend(extra_attributes)
 
+class VAL2Xattrs():
+    # Source: https://github.com/sippy/b2bua/pull/39
+    # Author: @twmobius
+    doO: bool = True
+    doA: bool = True
+    radius_parameters: list
+    def __init__(self, v:str):
+        radius_parameters = []
+        pairs = v.split(';')
+        for pair in pairs:
+            [key, _, value] = pair.partition("=")
+            if value == '': continue
+            radius_parameters.append((key, value))
+        self.radius_parameters = radius_parameters
+
+    def __call__(self, cc:'CallController', _:CCEventTry):
+        if self.doO and cc.acctO is not None:
+            cc.acctO.addAttributes(self.radius_parameters)
+        if self.doA and cc.acctA is not None:
+            cc.acctA.addAttributes(self.radius_parameters)
+
 class Nop():
     def __init__(self, v:str): pass
     def __call__(self, *a, **kwa): pass
 
+class VAL2XattrsA(VAL2Xattrs): doO = False
+class VAL2XattrsO(VAL2Xattrs): doA = False
+
 def getTransProc(value:str):
     rparts = value.split('[', 1)
     if not len(rparts) == 2 or not value.endswith(']'):
@@ -70,5 +95,5 @@ def getTransProc(value:str):
     return fclass(farg)
 
 if __name__ == '__main__':
-    for t in ('HDR2Xattrs[X-foo-hdr]',):
+    for t in ('HDR2Xattrs[X-foo-hdr]', 'VAL2Xattrs[foo=bar;baz=xxx]', 'VAL2XattrsA[foo=bar;baz=xxx]', 'VAL2XattrsO[foo=bar;baz=xxx]'):
         p = getTransProc(t)

sippy/RadiusAccounting.py

@@ -188,3 +188,7 @@ def _process_result(self, results, sip_cid, btime):
         else:
             message = 'Error sending Acct/%s request (delay is %.3f)\n' % (self.origin, delay)
         self.global_config['_sip_logger'].write(message, call_id = sip_cid)
+
+    def addAttributes(self, attributes):
+        self._attributes.extend(tuple(x) for x in attributes \
+                                if tuple(x) not in self._attributes)

sippy/b2bua_radius.py

@@ -374,6 +374,9 @@ def placeOriginate(self, oroute):
                 self.state = CCStateDead
                 return
         event.reason = self.eTry.reason
+        po_proc = oroute.params.get('po_proc', None)
+        if po_proc is not None:
+            po_proc(self, event)
         self.uaO.recvEvent(event)
 
     def disconnect(self, rtime = None):

tests/test_B2BTransforms.py

@@ -19,6 +19,9 @@ class TestB2BTransforms(unittest.TestCase):
     def test_getTransProc(self):
         transformations = [
             ('HDR2Xattrs[X-foo-hdr]', (FakeCC(), FakeRequest(self))),
+            ('VAL2Xattrs[foo=bar;baz=xxx]', (FakeCC(), FakeEvent())),
+            ('VAL2XattrsA[foo=bar;baz=xxx]', (FakeCC(), FakeEvent())),
+            ('VAL2XattrsO[foo=bar;baz=xxx]', (FakeCC(), FakeEvent())),
             ('Nop[]', (None, None)),
         ]