def fetch(request, name, res_type, consolidation):
"""Fetch the data from a specific RRD, in some time frame, with a particular resolution.
:param request: The original request.
:type request: HttpRequest
:param name: The name of the target resmon database.
:type name: str
:param res_type: The type of data: cpu | memory
:type res_type: str
:param consolidation: The optional consolidation function used. If specified must be one of: average | last.
The default is last.
:type consolidation; str
:return: The requested data set.
"""
try:
resolution = request.GET.get('resolution')
start = request.GET.get('start')
end = request.GET.get('end')
if not resolution:
resolution = '1s' # Default to the fastest resolution
if not end:
end = time.time() # Default to now
if not start:
start = end - (24 * 3600) # Default to one day worth of data
ts = time.time()
data = None
if consolidation == 'average':
data = rrdutil.fetch_avg_data(name + res_type + '.rrd', start_ts=int(start), end_ts=int(end), resolution=parse_timespec(resolution))
else:
data = rrdutil.fetch_last_data(name + res_type + '.rrd', start_ts=int(start), end_ts=int(end), resolution=parse_timespec(resolution))
resp = RestCmd('/resmon/fetch', _process_fetch_data(data))
if 'xml' in request.META.get('HTTP_ACCEPT'):
return HttpResponse(ElementTree.tostring(resp.export_xml()), content_type='application/xml')
return HttpResponse(resp.export_json(), content_type='application/json')
except Exception as e:
tb = sys.exc_info()[2]
logger.error('Encountered unexpected {0} at {1}'.format(e, traceback.format_tb(tb)))
return HttpResponseServerError('Encountered unexpected error, please check service log for more details')
def main(args):
"""Main entry to the gen_graph command.
:param args: Command line argument list. A list of strings.
:type args: list
:return: The return code for the command, 0 is success, anything else for failure
:rtype: int
"""
exit_code = 0 # Default to success
parser = None
try:
# Parse the given argument list
parser = argparse.ArgumentParser(prog='fetch', description='Fetch some resource utilisation data from a resmon DB')
parser.add_argument('-s', metavar='start_time', help='The start time, default to 24h before the end time',
type=int)
parser.add_argument('-e', metavar='end_time', help='The end time, default to now', type=int)
parser.add_argument('-c', help='Consolidation function: ave | last. Default to ave', type=str,
choices=['ave', 'last'], default='ave')
parser.add_argument('-r', help='Resolution of the requested data, e.g. 1s, 30s, 1m, ...', type=str, required=True)
parser.add_argument('-p', metavar='period/timeframe', help='If a start time is not specified then this will '
'specify the period of time against which the graph will cover. E.g. 23s, 5m, 6h, 1d, 2w',
type=str, default='1d')
parser.add_argument('-f', metavar='RRD_file', help='Name of the RRD file', type=str, required=True)
arg = parser.parse_args(args=args)
# Calculating the end timestamp
end_ts = int(time.time())
if arg.e: # End time
end_ts = int(arg.e)
# Calculating the start timestamp
start_ts = end_ts - (24 * 3600) # Default start time is one day old data
if arg.s: # Start time
start_ts = int(arg.s)
elif arg.p: # Period is meaningful only when start time is not specified
start_ts = end_ts - parse_timespec(arg.p)
ret = []
# Calculating the consolidation function
if arg.c == 'last':
ret += fetch_last_data(arg.f, start_ts=start_ts, end_ts=end_ts, resolution=parse_timespec(arg.r))
else:
ret += fetch_avg_data(arg.f, start_ts=start_ts, end_ts=end_ts, resolution=parse_timespec(arg.r))
if len(ret) > 2:
curr_ts = ret[0][0]
inc = int(ret[0][2])
print(rrd_fields_to_csv('ts', ret[1]))
for line in ret[2]:
print(rrd_fields_to_csv(curr_ts, line))
curr_ts += inc
except KeyboardInterrupt:
tb = sys.exc_info()[2]
logger.warning('User interruption at {0}'.format(format_tb(tb)))
exit_code = errno.EINTR
except ValueError as e:
tb = sys.exc_info()[2]
logger.warning('Encountered {0} at {1}'.format(e, format_tb(tb)))
exit_code = errno.EINVAL
except Exception as e:
tb = sys.exc_info()[2]
logger.warning('Encountered unexpected {0} at {1}'.format(e, format_tb(tb)))
exit_code = errno.EINVAL
return exit_code
