filter invalid number

asteriskserver/src/etc/asterisk/extensions.conf

@@ -458,7 +458,7 @@ exten => _211,1,Macro(dial,+18666986155)
 exten => _933,1,Macro(dial,${EXTEN})
 ; voip.ms 911 test, which must be in this format for some reason
 exten => _15555550911,1,Macro(dial,${EXTEN})
-; blocked information numbers go to operator
+; information numbers blocked by provider go to operator
 exten => _NXX5551212,1,Goto(operator,s,1)
 exten => _1NXX5551212,1,Goto(operator,s,1)
 ; 11 digit prefixed with 1: NANPA, normalize to e.164 with + prefix

asteriskserver/src/var/lib/asterisk/agi-bin/filter_outgoing.agi

@@ -12,6 +12,7 @@ agi = agi.AGI()
 
 config_filename = 'blocklist.yaml'
 
+# prefixes of expensive numbers
 premium_nampa_prefixes = [
     '1900',
     '1976',
@@ -36,14 +37,17 @@ premium_nampa_prefixes = [
     '1869',
     '1876']
 
+# prefixes of numbers which providers will fail
+invalid_prefixes = ['1911']
+
 def filter_blocklist(blocklist, number, extension):
     """Return True if number and extension are in blocklist."""
     return any(
         all([str(block_map.get('number')) == number,
              str(block_map.get('extension')) == extension])
         for block_map in blocklist)
 
-def filter_premium(prefixes, number):
+def filter_prefix(prefixes, number):
     """Return True if prefix of number is in prefixes."""
     return any(number.startswith(prefix) for prefix in prefixes)
 
@@ -55,9 +59,12 @@ def filter_outgoing(blocklist, number, extension):
         return                  # survive
     if number == '933':         # callcentric 911 test number
         return                  # survive
-    if filter_premium(premium_nampa_prefixes, number):
+    if filter_prefix(premium_nampa_prefixes, number):
         util.metric(agi, 'filter-outgoing-premium')
         agi.hangup()
+    if filter_prefix(invalid_prefixes, number):
+        util.metric(agi, 'filter-outgoing-invalid')
+        agi.hangup()
     if filter_blocklist(blocklist, number, extension):
         util.metric(agi, 'filter-outgoing-blocked')
         agi.hangup()