Optional, off by default: launches escape-fel's upcoming live parse-cache
warmer (`python -m escape.swissfel.live_reduce --mode daq-cache`) as a
genuine child process once per scan, right where copy_scan_info_to_raw
already knows scan_info_rel.json's path - see escape-fel's own
"Integrating live parse-cache warming into the DAQ client" doc for what the
subprocess itself does (polls for newly-complete steps, calls
load_dataset_from_scan with checknstore_parsing_result="same_directory" to
warm the cache next to scan_info_rel.json, exits once the run goes quiet).
Feature-gated on the actual implementing attribute
(escape.swissfel.live_reduce.daq_cache_writer), not just module presence,
so turning this on ahead of the escape-fel release that adds it is a
harmless no-op - checked at launch time, not at Daq construction, so it
starts working the moment escape-fel is upgraded without needing the flag
re-toggled. At most one child per scan (copy_scan_info_to_raw fires once
per step plus once at scan end, not just once) - reuses a still-running
one, relaunches only if the previous one already exited. A plain
subprocess.Popen of *this* process on purpose, per the doc's own warning:
the child needs to inherit whatever account this Daq/session runs as,
since a different account (even in the same pgroup) can fail to write the
cache file into aux/ outright.
Also: bernina.status_server now points at ECO_STATUS_SERVER's URL when one
is set (the same env var Daq already reads), instead of always the
production default - lets a session point both Daq and the inspectable
status_server object at a test server (e.g.
ECO_STATUS_SERVER=http://saresb-vcons-03:8092) without touching production.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
