Always raise subclasses of InvalidHandshake.

Also shorten messages for InvalidHeader exceptions.

Author: aaugustin

src/websockets/client.py

@@ -176,10 +176,7 @@ def process_response(self, response: Response) -> None:
         except KeyError as exc:
             raise InvalidHeader("Sec-WebSocket-Accept") from exc
         except MultipleValuesError as exc:
-            raise InvalidHeader(
-                "Sec-WebSocket-Accept",
-                "more than one Sec-WebSocket-Accept header found",
-            ) from exc
+            raise InvalidHeader("Sec-WebSocket-Accept", "multiple values") from exc
 
         if s_w_accept != accept_key(self.key):
             raise InvalidHeaderValue("Sec-WebSocket-Accept", s_w_accept)
@@ -225,7 +222,7 @@ def process_extensions(self, headers: Headers) -> list[Extension]:
 
         if extensions:
             if self.available_extensions is None:
-                raise InvalidHandshake("no extensions supported")
+                raise NegotiationError("no extensions supported")
 
             parsed_extensions: list[ExtensionHeader] = sum(
                 [parse_extension(header_value) for header_value in extensions], []
@@ -280,15 +277,17 @@ def process_subprotocol(self, headers: Headers) -> Subprotocol | None:
 
         if subprotocols:
             if self.available_subprotocols is None:
-                raise InvalidHandshake("no subprotocols supported")
+                raise NegotiationError("no subprotocols supported")
 
             parsed_subprotocols: Sequence[Subprotocol] = sum(
                 [parse_subprotocol(header_value) for header_value in subprotocols], []
             )
 
             if len(parsed_subprotocols) > 1:
-                subprotocols_display = ", ".join(parsed_subprotocols)
-                raise InvalidHandshake(f"multiple subprotocols: {subprotocols_display}")
+                raise InvalidHeader(
+                    "Sec-WebSocket-Protocol",
+                    f"multiple values: {', '.join(parsed_subprotocols)}",
+                )
 
             subprotocol = parsed_subprotocols[0]
 

src/websockets/datastructures.py

@@ -17,7 +17,7 @@
 
 class MultipleValuesError(LookupError):
     """
-    Exception raised when :class:`Headers` has more than one value for a key.
+    Exception raised when :class:`Headers` has multiple values for a key.
 
     """
 

src/websockets/legacy/client.py

@@ -19,10 +19,9 @@
 from ..asyncio.compatibility import asyncio_timeout
 from ..datastructures import Headers, HeadersLike
 from ..exceptions import (
-    InvalidHandshake,
     InvalidHeader,
+    InvalidHeaderValue,
     NegotiationError,
-
     SecurityError,
 )
 from ..extensions import ClientExtensionFactory, Extension
@@ -181,7 +180,7 @@ def process_extensions(
 
         if header_values:
             if available_extensions is None:
-                raise InvalidHandshake("no extensions supported")
+                raise NegotiationError("no extensions supported")
 
             parsed_header_values: list[ExtensionHeader] = sum(
                 [parse_extension(header_value) for header_value in header_values], []
@@ -235,15 +234,17 @@ def process_subprotocol(
 
         if header_values:
             if available_subprotocols is None:
-                raise InvalidHandshake("no subprotocols supported")
+                raise NegotiationError("no subprotocols supported")
 
             parsed_header_values: Sequence[Subprotocol] = sum(
                 [parse_subprotocol(header_value) for header_value in header_values], []
             )
 
             if len(parsed_header_values) > 1:
-                subprotocols = ", ".join(parsed_header_values)
-                raise InvalidHandshake(f"multiple subprotocols: {subprotocols}")
+                raise InvalidHeaderValue(
+                    "Sec-WebSocket-Protocol",
+                    f"multiple values: {', '.join(parsed_header_values)}",
+                )
 
             subprotocol = parsed_header_values[0]
 

src/websockets/legacy/handshake.py

@@ -76,9 +76,7 @@ def check_request(headers: Headers) -> str:
     except KeyError as exc:
         raise InvalidHeader("Sec-WebSocket-Key") from exc
     except MultipleValuesError as exc:
-        raise InvalidHeader(
-            "Sec-WebSocket-Key", "more than one Sec-WebSocket-Key header found"
-        ) from exc
+        raise InvalidHeader("Sec-WebSocket-Key", "multiple values") from exc
 
     try:
         raw_key = base64.b64decode(s_w_key.encode(), validate=True)
@@ -92,9 +90,7 @@ def check_request(headers: Headers) -> str:
     except KeyError as exc:
         raise InvalidHeader("Sec-WebSocket-Version") from exc
     except MultipleValuesError as exc:
-        raise InvalidHeader(
-            "Sec-WebSocket-Version", "more than one Sec-WebSocket-Version header found"
-        ) from exc
+        raise InvalidHeader("Sec-WebSocket-Version", "multiple values") from exc
 
     if s_w_version != "13":
         raise InvalidHeaderValue("Sec-WebSocket-Version", s_w_version)
@@ -156,9 +152,7 @@ def check_response(headers: Headers, key: str) -> None:
     except KeyError as exc:
         raise InvalidHeader("Sec-WebSocket-Accept") from exc
     except MultipleValuesError as exc:
-        raise InvalidHeader(
-            "Sec-WebSocket-Accept", "more than one Sec-WebSocket-Accept header found"
-        ) from exc
+        raise InvalidHeader("Sec-WebSocket-Accept", "multiple values") from exc
 
     if s_w_accept != accept(key):
         raise InvalidHeaderValue("Sec-WebSocket-Accept", s_w_accept)

src/websockets/legacy/server.py

@@ -397,7 +397,7 @@ def process_origin(
         try:
             origin = headers.get("Origin")
         except MultipleValuesError as exc:
-            raise InvalidHeader("Origin", "more than one Origin header found") from exc
+            raise InvalidHeader("Origin", "multiple values") from exc
         if origin is not None:
             origin = cast(Origin, origin)
         if origins is not None:

src/websockets/server.py

@@ -257,9 +257,7 @@ def process_request(
         except KeyError as exc:
             raise InvalidHeader("Sec-WebSocket-Key") from exc
         except MultipleValuesError as exc:
-            raise InvalidHeader(
-                "Sec-WebSocket-Key", "more than one Sec-WebSocket-Key header found"
-            ) from exc
+            raise InvalidHeader("Sec-WebSocket-Key", "multiple values") from exc
 
         try:
             raw_key = base64.b64decode(key.encode(), validate=True)
@@ -273,10 +271,7 @@ def process_request(
         except KeyError as exc:
             raise InvalidHeader("Sec-WebSocket-Version") from exc
         except MultipleValuesError as exc:
-            raise InvalidHeader(
-                "Sec-WebSocket-Version",
-                "more than one Sec-WebSocket-Version header found",
-            ) from exc
+            raise InvalidHeader("Sec-WebSocket-Version", "multiple values") from exc
 
         if version != "13":
             raise InvalidHeaderValue("Sec-WebSocket-Version", version)
@@ -315,7 +310,7 @@ def process_origin(self, headers: Headers) -> Origin | None:
         try:
             origin = headers.get("Origin")
         except MultipleValuesError as exc:
-            raise InvalidHeader("Origin", "more than one Origin header found") from exc
+            raise InvalidHeader("Origin", "multiple values") from exc
         if origin is not None:
             origin = cast(Origin, origin)
         if self.origins is not None:

tests/test_client.py

@@ -342,8 +342,7 @@ def test_multiple_accept(self):
             raise client.handshake_exc
         self.assertEqual(
             str(raised.exception),
-            "invalid Sec-WebSocket-Accept header: "
-            "more than one Sec-WebSocket-Accept header found",
+            "invalid Sec-WebSocket-Accept header: multiple values",
         )
 
     def test_invalid_accept(self):
@@ -556,7 +555,9 @@ def test_multiple_subprotocols(self):
         with self.assertRaises(InvalidHandshake) as raised:
             raise client.handshake_exc
         self.assertEqual(
-            str(raised.exception), "multiple subprotocols: superchat, chat"
+            str(raised.exception),
+            "invalid Sec-WebSocket-Protocol header: "
+            "multiple values: superchat, chat",
         )
 
     def test_supported_subprotocol(self):

tests/test_server.py

@@ -305,8 +305,7 @@ def test_multiple_key(self):
             raise server.handshake_exc
         self.assertEqual(
             str(raised.exception),
-            "invalid Sec-WebSocket-Key header: "
-            "more than one Sec-WebSocket-Key header found",
+            "invalid Sec-WebSocket-Key header: multiple values",
         )
 
     def test_invalid_key(self):
@@ -366,8 +365,7 @@ def test_multiple_version(self):
             raise server.handshake_exc
         self.assertEqual(
             str(raised.exception),
-            "invalid Sec-WebSocket-Version header: "
-            "more than one Sec-WebSocket-Version header found",
+            "invalid Sec-WebSocket-Version header: multiple values",
         )
 
     def test_invalid_version(self):
@@ -437,7 +435,7 @@ def test_multiple_origin(self):
             raise server.handshake_exc
         self.assertEqual(
             str(raised.exception),
-            "invalid Origin header: more than one Origin header found",
+            "invalid Origin header: multiple values",
         )
 
     def test_supported_origin(self):