class QSBackend(JSONBackend):
"""
Questionniare Backend
This backend connects to the LCLS questionnaire and looks at devices with
the key pattern pcds-{}-setup-{}-{}. These fields are then combined and
turned into proper happi devices. The translation of table name to
``happi.HappiItem`` is determined by the :attr:`.device_translations`
dictionary. The beamline is determined by looking where the proposal was
submitted.
Unlike the other backends, this one is read-only. All changes to the device
information should be done via the web interface. Finally, in order to
avoid duplicating any code needed to search the device database, the
QSBackend inherits directly from JSONBackend. Many of the functions are
unmodified with exception being that this backend merely searchs through an
in memory dictionary while the JSONBackend reads from the file before
searches.
Parameters
----------
expname : str
The experiment name from the elog, e.g. xcslp1915
"""
device_translations = {
'motors': 'Motor',
'trig': 'Trigger',
'ao': 'Acromag',
'ai': 'Acromag'
}
def __init__(self, expname, **kwargs):
# Create our client and gather the raw information from the client
self.qs = QuestionnaireClient(**kwargs)
# Get the proposal number
exp_dict = self.qs.getExpName2URAWIProposalIDs()
try:
proposal = exp_dict[expname]
except KeyError:
# Rare case for debug/daq experiments, roll with it for now
proposal = expname
run_no = 'run{}'.format(expname[-2:])
try:
logger.debug("Requesting list of proposals in %s", run_no)
prop_ids = self.qs.getProposalsListForRun(run_no)
try:
beamline = prop_ids[proposal]['Instrument']
except KeyError:
# Rare care for debug/daq experiments
beamline = prop_ids[expname]['Instrument']
proposal = expname
# Invalid proposal id for this run
except KeyError as exc:
raise DatabaseError('Unable to find proposal {}'.format(proposal))\
from exc
# Find if our exception gave an HTTP status code and interpret it
except Exception as exc:
if len(exc.args) > 1:
status_code = exc.args[1]
else:
status_code = ''
# No information found from run
if status_code == 500:
reason = 'No run id found for {}'.format(run_no)
# Invalid credentials
elif status_code == 401:
reason = 'Invalid credentials'
# Unrecognized error
else:
reason = 'Unable to find run information'
raise DatabaseError(reason) from exc
# Interpret the raw information into a happi structured dictionary
self.db = dict()
logger.debug("Requesting proposal information for %s", proposal)
raw = self.qs.getProposalDetailsForRun(run_no, proposal)
for table, _class in self.device_translations.items():
# Create a regex pattern to find all the appropriate pattern match
pattern = re.compile(r'pcdssetup-{}' r'-(\d+)-(\w+)'.format(table))
# Search for all keys that match the device and store in a
# temporary dictionary
devices = dict()
for field in raw.keys():
match = pattern.match(field)
if match:
dev_no = match.group(1)
# Create an empty dictionary for the specific device
# information
if dev_no not in devices:
devices[dev_no] = dict()
# Add the key information to the specific device dictionary
devices[dev_no][match.group(2)] = raw[field]
# Store the devices as happi items
if not devices:
logger.info("No device information found under '%s'", table)
else:
logger.debug("Found %s devices under %s table", len(devices),
table)
for num, dev_info in devices.items():
try:
post = {
'name': dev_info.pop('name'),
'prefix': dev_info['pvbase'],
'beamline': beamline,
'type': _class,
# TODO: We should not assume that we are using
# the prefix as _id. Other backends do not make
# this assumption. This will require moving the
# _id configuration from Client to Backend
'_id': dev_info.pop('pvbase')
}
# Add extraneous metadata
post.update(dev_info)
# Check that the we haven't received empty strings from
# the Questionnaire
for key in ['prefix', 'name']:
if not post.get(key):
raise Exception("Unable to create a device "
" without %s" % key)
except Exception:
logger.warning(
"Unable to create an object from "
"Questionnaire table %s row %s", table, num)
else:
self.db[post['_id']] = post
def initialize(self):
"""
Can not initialize a new Questionnaire entry from API
"""
raise NotImplementedError("The Questionnaire backend is read-only")
def load(self):
"""
Return the structured dictionary of information
"""
return self.db
def store(self, *args, **kwargs):
"""
The current implementation of this backend is read-only
"""
raise NotImplementedError("The Questionnaire backend is read-only")
def save(self, *args, **kwargs):
"""
The current implementation of this backend is read-only
"""
raise NotImplementedError("The Questionnaire backend is read-only")
def delete(self, _id):
"""
The current implementation of this backend is read-only
"""
raise NotImplementedError("The Questionnaire backend is read-only")
def __init__(self, client: QuestionnaireClient):
self._client = client
self._experiment = None
self.experiment_to_proposal = client.getExpName2URAWIProposalIDs()