bencher.bench_plot_server
=========================

.. py:module:: bencher.bench_plot_server

.. autoapi-nested-parse::

   A server for display plots of benchmark results



Attributes
----------

.. autoapisummary::

   bencher.bench_plot_server._PORT_RANGE_MIN
   bencher.bench_plot_server._PORT_RANGE_MAX
   bencher.bench_plot_server._PORT_PROBE_ATTEMPTS


Classes
-------

.. autoapisummary::

   bencher.bench_plot_server._CorsStaticHandler
   bencher.bench_plot_server.BenchPlotServer


Module Contents
---------------

.. py:data:: _PORT_RANGE_MIN
   :value: 49152


.. py:data:: _PORT_RANGE_MAX
   :value: 65535


.. py:data:: _PORT_PROBE_ATTEMPTS
   :value: 100


.. py:class:: _CorsStaticHandler(application: Application, request: tornado.httputil.HTTPServerRequest, **kwargs: Any)

   Bases: :py:obj:`tornado.web.StaticFileHandler`


   A Tornado static file handler that adds CORS headers.

   Required for rerun integration: the rerun web viewer fetches .rrd files
   from the Panel server.  Without Access-Control-Allow-Origin and OPTIONS
   preflight handling the browser silently blocks the cross-origin fetch
   and the viewer shows 0 B.

   Note: ``Allow-Origin: *`` is appropriate here because this server is
   intended for local development only, not public-facing deployments.


   .. py:method:: data_received(chunk)

      Implement this method to handle streamed request data.

      Requires the `.stream_request_body` decorator.

      May be a coroutine for flow control.



   .. py:method:: set_default_headers()

      Override this to set HTTP headers at the beginning of the request.

      For example, this is the place to set a custom ``Server`` header.
      Note that setting such headers in the normal flow of request
      processing may not do what you want, since headers may be reset
      during error handling.



   .. py:method:: options(*_args)


.. py:class:: BenchPlotServer

   A server for display plots of benchmark results


   .. py:method:: plot_server(bench_name: str, plot_cfg: bencher.bench_cfg.BenchPlotSrvCfg | None = None, plots_instance=None) -> threading.Thread

      Load previously calculated benchmark data from the database and start a plot server to display it

      :param bench_name: The name of the benchmark and output folder for the figures
      :type bench_name: str
      :param plot_cfg: Options for the plot server. Defaults to None.
      :type plot_cfg: BenchPlotSrvCfg, optional

      :raises FileNotFoundError: No data found was found in the database to plot



   .. py:method:: load_data_from_cache(bench_name: str) -> tuple[bencher.bench_cfg.BenchCfg, list[panel.panel]] | None

      Load previously calculated benchmark data from the database and start a plot server to display it

      :param bench_name: The name of the benchmark and output folder for the figures
      :type bench_name: str

      :returns: benchmark result data and any additional panels
      :rtype: tuple[BenchCfg, list[pn.panel]] | None

      :raises FileNotFoundError: No data found was found in the database to plot



   .. py:method:: _find_free_port() -> int
      :staticmethod:


      Find a free port by testing random ports in the dynamic/private range.

      Using ``port=0`` with Tornado/Bokeh can fail on some Linux kernels
      (notably 6.x) because the kernel deterministically assigns the same
      ephemeral port, causing ``EADDRINUSE`` when a previous server is
      still running.  Picking a random port from the IANA dynamic range
      avoids this.

      Note: there is an inherent TOCTOU race between probing the port here
      and the actual ``bind()`` inside Panel/Bokeh.  In practice the window
      is very small and the random selection makes collisions unlikely, but
      callers should be prepared for a rare ``OSError`` on server start.



   .. py:method:: serve(bench_name: str, plots_instance: list[panel.panel], port: int | None = None, show: bool = True) -> threading.Thread

      Launch a panel server to view results


      :param bench_cfg: benchmark results
      :type bench_cfg: BenchCfg
      :param plots_instance: list of panel objects to display
      :type plots_instance: list[pn.panel]
      :param port: use a fixed port to launch the server
      :type port: int



   .. py:method:: _rrd_extra_patterns() -> list
      :staticmethod:


      Return Tornado route patterns for serving .rrd files with CORS headers.

      Mounts ``cachedir/rrd/`` at ``/rrd_static/`` so that the local rerun
      viewer can fetch ``.rrd`` files from the Panel server.  See the module
      docstring in ``utils_rerun.py`` for the full architecture explanation.