'''
Values the application writes while it runs.
These are not configuration. The log filename and the profiling flag are
decided by the launcher after the process starts; nobody sets them in a
file or the environment, and setting them there would either do nothing
or confuse the launcher.
Only values with nowhere else to live belong here. Logging is configured
before the workbench exists, and the acquisition thread that reads the
profiling flag has no workbench in reach, so both are genuinely ambient.
The experiment name was kept here too and was not: every reader was a
command handler holding an `event.workbench`, and start_workspace was
already handed the name. It lives on PSIWorkbench now.
They used to live in the same dictionary as the settings, which made that
dictionary two things at once: a user would reasonably conclude from
``get_config('LOG_FILENAME')`` that ``PSI_LOG_FILENAME`` was a variable
they could set, and it is not. Keeping them here means the configuration
system can state without exceptions that every setting has a file
spelling and an environment spelling.
'''
import logging
log = logging.getLogger(__name__)
NoDefault = object()
_runtime = {}
[docs]
def set_runtime(name, value):
'''
Record a runtime value.
'''
_runtime[name] = value
log.debug('Runtime value %s set', name)
[docs]
def get_runtime(name, default=NoDefault):
'''
Read a runtime value.
Raises
------
KeyError
If the value has not been set and no default was supplied. This
means the launcher has not run the step that sets it.
'''
if name in _runtime:
return _runtime[name]
if default is NoDefault:
raise KeyError(
f'{name} has not been set. Runtime values are written by the '
'launcher while the application starts; they are not settings '
'and cannot be supplied through the configuration file or the '
'environment.')
return default
[docs]
def clear_runtime():
'''
Forget every runtime value. For tests.
'''
_runtime.clear()