team-10/venv/Lib/site-packages/streamlit/web/server/stats_request_handler.py
2025-08-02 02:00:33 +02:00

86 lines
3 KiB
Python

# Copyright 2018-2022 Streamlit Inc.
#
# 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 typing import List
import tornado.web
from streamlit.proto.openmetrics_data_model_pb2 import (
MetricSet as MetricSetProto,
GAUGE,
)
from streamlit.runtime.stats import StatsManager, CacheStat
class StatsRequestHandler(tornado.web.RequestHandler):
def initialize(self, stats_manager: StatsManager) -> None:
self._manager = stats_manager
def set_default_headers(self):
# Avoid a circular import
from streamlit.web.server import allow_cross_origin_requests
if allow_cross_origin_requests():
self.set_header("Access-Control-Allow-Origin", "*")
def options(self):
"""/OPTIONS handler for preflight CORS checks."""
self.set_status(204)
self.finish()
def get(self) -> None:
stats = self._manager.get_stats()
# If the request asked for protobuf output, we return a serialized
# protobuf. Else we return text.
if "application/x-protobuf" in self.request.headers.get_list("Accept"):
self.write(self._stats_to_proto(stats).SerializeToString())
self.set_header("Content-Type", "application/x-protobuf")
self.set_status(200)
else:
self.write(self._stats_to_text(self._manager.get_stats()))
self.set_header("Content-Type", "application/openmetrics-text")
self.set_status(200)
@staticmethod
def _stats_to_text(stats: List[CacheStat]) -> str:
metric_type = "# TYPE cache_memory_bytes gauge"
metric_unit = "# UNIT cache_memory_bytes bytes"
metric_help = "# HELP Total memory consumed by a cache."
openmetrics_eof = "# EOF\n"
# Format: header, stats, EOF
result = [metric_type, metric_unit, metric_help]
result.extend(stat.to_metric_str() for stat in stats)
result.append(openmetrics_eof)
return "\n".join(result)
@staticmethod
def _stats_to_proto(stats: List[CacheStat]) -> MetricSetProto:
metric_set = MetricSetProto()
metric_family = metric_set.metric_families.add()
metric_family.name = "cache_memory_bytes"
metric_family.type = GAUGE
metric_family.unit = "bytes"
metric_family.help = "Total memory consumed by a cache."
for stat in stats:
metric_proto = metric_family.metrics.add()
stat.marshall_metric_proto(metric_proto)
metric_set = MetricSetProto()
metric_set.metric_families.append(metric_family)
return metric_set