Make it possible to parse multiple Address and Via from a string

src/sipmessage/address.py

@@ -6,7 +6,7 @@
 import dataclasses
 import re
 
-from . import grammar
+from . import grammar, utils
 from .parameters import Parameters
 from .uri import URI
 
@@ -22,7 +22,6 @@
         "<(?P<uri>[^>]+)>"
         # *(SEMI contact-params)
         f"(?P<parameters>(?:{grammar.SEMI}{grammar.GENERIC_PARAM})*)"
-        "$"
     ),
     # addr-spec *(SEMI contact-params)
     re.compile(
@@ -32,7 +31,6 @@
         "(?P<uri>[^ ;]+)"
         # *(SEMI contact-params)
         f"(?P<parameters>(?:{grammar.SEMI}{grammar.GENERIC_PARAM})*)"
-        "$"
     ),
 ]
 
@@ -70,15 +68,29 @@ def parse(cls, value: str) -> "Address":
 
         If parsing fails, a :class:`ValueError` is raised.
         """
-        value = grammar.simplify_whitespace(value)
+        return utils.parse_single(cls._parse_one, value)
 
+    @classmethod
+    def parse_many(cls, value: str) -> "list[Address]":
+        """
+        Parse the given string into a list of :class:`Address` instances.
+
+        If parsing fails, a :class:`ValueError` is raised.
+        """
+        return utils.parse_many(cls._parse_one, value)
+
+    @classmethod
+    def _parse_one(cls, value: str) -> "tuple[Address, str]":
         for pattern in ADDRESS_PATTERNS:
             m = pattern.match(value)
             if m:
-                return cls(
-                    uri=URI.parse(m.group("uri")),
-                    name=unquote(m.group("name").strip()),
-                    parameters=Parameters.parse(m.group("parameters")),
+                return (
+                    cls(
+                        uri=URI.parse(m.group("uri")),
+                        name=unquote(m.group("name").strip()),
+                        parameters=Parameters.parse(m.group("parameters")),
+                    ),
+                    value[m.end() :],
                 )
         else:
             raise ValueError("Address is not valid")

src/sipmessage/utils.py

@@ -0,0 +1,30 @@
+import typing
+
+from . import grammar
+
+T = typing.TypeVar("T")
+
+
+def parse_many(parser: typing.Callable[[str], tuple[T, str]], value: str) -> list[T]:
+    value = grammar.simplify_whitespace(value)
+
+    items: list[T] = []
+    while value:
+        item, value = parser(value)
+        items.append(item)
+
+        # Consume list separator(s).
+        while value.startswith(","):
+            value = value[1:].lstrip()
+
+    return items
+
+
+def parse_single(parser: typing.Callable[[str], tuple[T, str]], value: str) -> T:
+    value = grammar.simplify_whitespace(value)
+
+    item, value = parser(value)
+    if value:
+        raise ValueError("Header has trailing data")
+
+    return item

src/sipmessage/via.py

@@ -6,15 +6,14 @@
 import dataclasses
 import re
 
-from . import grammar
+from . import grammar, utils
 from .parameters import Parameters
 
 VIA_PATTERN = re.compile(
     f"^SIP{grammar.SLASH}2\\.0{grammar.SLASH}(?P<transport>{grammar.TOKEN}) "
     f"(?P<host>{grammar.HOST})"
     f"(?::(?P<port>{grammar.PORT}))?"
     f"(?P<parameters>(?:{grammar.SEMI}{grammar.GENERIC_PARAM})*)"
-    "$"
 )
 
 
@@ -43,8 +42,19 @@ def parse(cls, value: str) -> "Via":
 
         If parsing fails, a :class:`ValueError` is raised.
         """
-        value = grammar.simplify_whitespace(value)
+        return utils.parse_single(cls._parse_one, value)
 
+    @classmethod
+    def parse_many(cls, value: str) -> "list[Via]":
+        """
+        Parse the given string into a list of :class:`Via` instances.
+
+        If parsing fails, a :class:`ValueError` is raised.
+        """
+        return utils.parse_many(cls._parse_one, value)
+
+    @classmethod
+    def _parse_one(cls, value: str) -> tuple["Via", str]:
         m = VIA_PATTERN.match(value)
         if m is None:
             raise ValueError("Via is not valid")
@@ -56,7 +66,7 @@ def parse(cls, value: str) -> "Via":
             host=m.group("host"),
             port=int(port) if port else None,
             parameters=Parameters.parse(m.group("parameters")),
-        )
+        ), value[m.end() :]
 
     def __str__(self) -> str:
         s = f"SIP/2.0/{self.transport} {self.host}"

tests/test_address.py

@@ -200,3 +200,23 @@ def test_rfc4475_intmeth_to(self) -> None:
             '"BEL:\x07 NUL:\x00 DEL:\x7f" '
             "<sip:1_unusual.URI~(to-be!sure)&isn't+it$/crazy?,/;;*@example.com>",
         )
+
+    def test_trailing_comma(self) -> None:
+        with self.assertRaises(ValueError) as cm:
+            Address.parse("<sip:1.2.3.4;lr>,")
+        self.assertEqual(str(cm.exception), "Header has trailing data")
+
+
+class AddressParseManyTest(unittest.TestCase):
+    def test_simple(self) -> None:
+        contacts = Address.parse_many(
+            "<sip:[email protected]>, <sip:[email protected]>, <sip:[email protected]>"
+        )
+        self.assertEqual(
+            contacts,
+            [
+                Address(uri=URI(scheme="sip", host="atlanta.com", user="alice")),
+                Address(uri=URI(scheme="sip", host="biloxi.com", user="bob")),
+                Address(uri=URI(scheme="sip", host="chicago.com", user="carol")),
+            ],
+        )

tests/test_via.py

@@ -116,3 +116,26 @@ def test_rfc4475_wsinv(self) -> None:
                 parameters=Parameters(branch="z9hG4bK30239"),
             ),
         )
+
+
+class ViaParseManyTest(unittest.TestCase):
+    def test_simple(self) -> None:
+        vias = Via.parse_many(
+            "SIP/2.0/UDP 192.168.255.111;branch=z9hG4bK30239, "
+            "SIP/2.0/WSS T8trJdbBz7r6.invalid;branch=z9hG4bKYJHC9fb"
+        )
+        self.assertEqual(
+            vias,
+            [
+                Via(
+                    transport="UDP",
+                    host="192.168.255.111",
+                    parameters=Parameters(branch="z9hG4bK30239"),
+                ),
+                Via(
+                    transport="WSS",
+                    host="T8trJdbBz7r6.invalid",
+                    parameters=Parameters(branch="z9hG4bKYJHC9fb"),
+                ),
+            ],
+        )