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

120 lines
4.3 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.
from __future__ import annotations
import mimetypes
import os
from typing import TYPE_CHECKING, Final, cast
import tornado.web
import streamlit.web.server.routes
from streamlit.logger import get_logger
if TYPE_CHECKING:
from streamlit.components.types.base_component_registry import BaseComponentRegistry
_LOGGER: Final = get_logger(__name__)
class ComponentRequestHandler(tornado.web.RequestHandler):
def initialize(self, registry: BaseComponentRegistry) -> None:
self._registry = registry
def get(self, path: str) -> None:
parts = path.split("/")
component_name = parts[0]
component_root = self._registry.get_component_path(component_name)
if component_root is None:
self.write("not found")
self.set_status(404)
return
# follow symlinks to get an accurate normalized path
component_root = os.path.realpath(component_root)
filename = "/".join(parts[1:])
abspath = os.path.normpath(os.path.join(component_root, filename))
# Do NOT expose anything outside of the component root.
if os.path.commonpath([component_root, abspath]) != component_root:
self.write("forbidden")
self.set_status(403)
return
try:
with open(abspath, "rb") as file:
contents = file.read()
except OSError:
sanitized_abspath = abspath.replace("\n", "").replace("\r", "")
_LOGGER.exception(
"ComponentRequestHandler: GET %s read error", sanitized_abspath
)
self.write("read error")
self.set_status(404)
return
self.write(contents)
self.set_header("Content-Type", self.get_content_type(abspath))
self.set_extra_headers(path)
def set_extra_headers(self, path: str) -> None:
"""Disable cache for HTML files.
Other assets like JS and CSS are suffixed with their hash, so they can
be cached indefinitely.
"""
is_index_url = len(path) == 0
if is_index_url or path.endswith(".html"):
self.set_header("Cache-Control", "no-cache")
else:
self.set_header("Cache-Control", "public")
def set_default_headers(self) -> None:
if streamlit.web.server.routes.allow_all_cross_origin_requests():
self.set_header("Access-Control-Allow-Origin", "*")
elif streamlit.web.server.routes.is_allowed_origin(
origin := self.request.headers.get("Origin")
):
self.set_header("Access-Control-Allow-Origin", cast("str", origin))
def options(self) -> None:
"""/OPTIONS handler for preflight CORS checks."""
self.set_status(204)
self.finish()
@staticmethod
def get_content_type(abspath: str) -> str:
"""Returns the ``Content-Type`` header to be used for this request.
From tornado.web.StaticFileHandler.
"""
mime_type, encoding = mimetypes.guess_type(abspath)
# per RFC 6713, use the appropriate type for a gzip compressed file
if encoding == "gzip":
return "application/gzip"
# As of 2015-07-21 there is no bzip2 encoding defined at
# http://www.iana.org/assignments/media-types/media-types.xhtml
# So for that (and any other encoding), use octet-stream.
if encoding is not None:
return "application/octet-stream"
if mime_type is not None:
return mime_type
# if mime_type not detected, use application/octet-stream
return "application/octet-stream"
@staticmethod
def get_url(file_id: str) -> str:
"""Return the URL for a component file with the given ID."""
return f"components/{file_id}"