team-10/env/Lib/site-packages/streamlit/runtime/runtime_util.py
2025-08-02 07:34:44 +02:00

108 lines
3.9 KiB
Python

# Copyright (c) Streamlit Inc. (2018-2022) Snowflake Inc. (2022-2025)
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""Runtime-related utility functions."""
from __future__ import annotations
from logging import getLogger
from typing import TYPE_CHECKING, Any, Final, cast
from streamlit import config
from streamlit.errors import MarkdownFormattedException, StreamlitAPIException
if TYPE_CHECKING:
from streamlit.proto.ForwardMsg_pb2 import ForwardMsg
_LOGGER: Final = getLogger(__name__)
class MessageSizeError(MarkdownFormattedException):
"""Exception raised when a websocket message is larger than the configured limit."""
def __init__(self, failed_msg_str: Any) -> None:
msg = self._get_message(failed_msg_str)
super().__init__(msg)
def _get_message(self, failed_msg_str: Any) -> str:
# This needs to have zero indentation otherwise the markdown will render incorrectly.
return (
f"""
**Data of size {len(failed_msg_str) / 1e6:.1f} MB exceeds the message size limit of
{get_max_message_size_bytes() / 1e6} MB.**
This is often caused by a large chart or dataframe. Please decrease the amount of data sent
to the browser, or increase the limit by setting the config option `server.maxMessageSize`.
[Click here to learn more about config options](https://docs.streamlit.io/develop/api-reference/configuration/config.toml).
_Note that increasing the limit may lead to long loading times and large memory consumption
of the client's browser and the Streamlit server._
"""
).strip("\n")
class BadDurationStringError(StreamlitAPIException):
"""Raised when a bad duration argument string is passed."""
def __init__(self, duration: str) -> None:
MarkdownFormattedException.__init__(
self,
"TTL string doesn't look right. It should be formatted as"
f"`'1d2h34m'` or `2 days`, for example. Got: {duration}",
)
def serialize_forward_msg(msg: ForwardMsg) -> bytes:
"""Serialize a ForwardMsg to send to a client.
If the message is too large, it will be converted to an exception message
instead.
"""
msg_str = msg.SerializeToString()
if len(msg_str) > get_max_message_size_bytes():
# Overwrite the offending ForwardMsg.delta with an error to display.
# This assumes that the size limit wasn't exceeded due to metadata.
from streamlit.elements import exception
msg_size_error = MessageSizeError(msg_str)
_LOGGER.warning(
"Websocket message size limit exceeded. Showing error to the user: %s",
msg_size_error,
)
exception.marshall(msg.delta.new_element.exception, msg_size_error)
# Deactivate caching for this error message:
msg.metadata.cacheable = False
msg_str = msg.SerializeToString()
return msg_str
# This needs to be initialized lazily to avoid calling config.get_option() and
# thus initializing config options when this file is first imported.
_max_message_size_bytes: int | None = None
def get_max_message_size_bytes() -> int:
"""Returns the max websocket message size in bytes.
This will lazyload the value from the config and store it in the global symbol table.
"""
global _max_message_size_bytes # noqa: PLW0603
if _max_message_size_bytes is None:
_max_message_size_bytes = config.get_option("server.maxMessageSize") * int(1e6)
return cast("int", _max_message_size_bytes)