Add documentation around read buffer; Raise clear exception:

- Document ``read_buffer_limit`` on the ``AsyncIPCProvider`` class.

- Add ``ReadBufferLimitReached`` exception to be raised when the read buffer
  limit is reached, prompting the user to increase the limit.

- Add a base ``PersistentConnectionError`` exception class for persistent
  connection errors to inherit from.

Author: fselmo

docs/providers.rst

@@ -269,6 +269,10 @@ AsyncIPCProvider
     JSON-RPC server.
 
     *  ``ipc_path`` is the filesystem path to the IPC socket:
+    *  ``read_buffer_limit`` is the maximum size of data, in bytes, that can be read
+       from the socket at one time. Defaults to 20MB (20 * 1024 * 1024). Raises
+       ``ReadBufferLimitReached`` if the limit is reached, suggesting that the buffer
+       limit be increased.
 
     This provider inherits from the
     :class:`~web3.providers.persistent.PersistentConnectionProvider` class. Refer to

newsfragments/3492.feature.rst

@@ -1 +1 @@
-Add a configuration option for the ``read_buffer_limit`` for ``AsyncIPCProvider`` in order to control the expected message size limit. Set this default value to 20MB.
+Add a configuration option for the ``read_buffer_limit`` for ``AsyncIPCProvider`` in order to control the expected message size limit (defaults to 20MB). Add ``ReadBufferLimitReached`` for when the read limit is reached, extend from ``PersistentConnectionError``.

tests/core/providers/test_async_ipc_provider.py

@@ -19,6 +19,9 @@
 from web3.datastructures import (
     AttributeDict,
 )
+from web3.exceptions import (
+    ReadBufferLimitReached,
+)
 from web3.providers import (
     AsyncIPCProvider,
 )
@@ -312,7 +315,13 @@ async def test_async_ipc_reader_can_read_20mb_message(
 async def test_async_ipc_reader_raises_on_msg_over_20mb(
     jsonrpc_ipc_pipe_path, serve_larger_than_20mb_response
 ):
-    with pytest.raises(ValueError):
+    with pytest.raises(
+        ReadBufferLimitReached,
+        match=(
+            rf"Read buffer limit of `{TWENTY_MB}` bytes was reached. "
+            "Consider increasing the ``read_buffer_limit`` on the AsyncIPCProvider."
+        ),
+    ):
         async with AsyncWeb3(
             AsyncIPCProvider(pathlib.Path(jsonrpc_ipc_pipe_path))
         ) as w3:

web3/exceptions.py

@@ -334,7 +334,20 @@ def __init__(
         super().__init__(message)
 
 
-class PersistentConnectionClosedOK(Web3Exception):
+class PersistentConnectionError(Web3Exception):
+    """
+    Raised when a persistent connection encounters an error.
+    """
+
+
+class ReadBufferLimitReached(PersistentConnectionError):
+    """
+    Raised when the read buffer limit is reached while reading data from a persistent
+    connection.
+    """
+
+
+class PersistentConnectionClosedOK(PersistentConnectionError):
     """
     Raised when a persistent connection is closed gracefully by the server.
     """

web3/providers/persistent/async_ipc.py

@@ -23,6 +23,7 @@
 from ...exceptions import (
     PersistentConnectionClosedOK,
     ProviderConnectionError,
+    ReadBufferLimitReached,
     Web3TypeError,
 )
 from ..ipc import (
@@ -96,7 +97,17 @@ async def socket_send(self, request_data: bytes) -> None:
         )
 
     async def socket_recv(self) -> RPCResponse:
-        data = await self._reader.readline()
+        try:
+            data = await self._reader.readline()
+        except ValueError as e:
+            if all(kw in str(e) for kw in ("limit", "chunk")):
+                raise ReadBufferLimitReached(
+                    f"Read buffer limit of `{self.read_buffer_limit}` bytes was "
+                    "reached. Consider increasing the ``read_buffer_limit`` on the "
+                    "AsyncIPCProvider."
+                ) from e
+            raise
+
         if not data:
             raise PersistentConnectionClosedOK("Socket reader received end of stream.")
         return self.decode_rpc_response(data)