Restore and serve EPICS PVs from the Archiver¶

Using a simple JSON file to seed a dict of pvname:{'value':value}, this will acquire values from the archiver, and run a simple EPICS server locally.

In [1]:

from lcls_live.archiver import lcls_archiver_restore
import json
import os

from lcls_live.archiver import lcls_archiver_restore import json import os

In [2]:

# A list of some interesting PVs
PVDB_JSON = 'data/live_model_PVDB.json'

# Pick a proper time
ISOTIME = '2021-04-13T15:14:00.000000-07:00'

# A list of some interesting PVs PVDB_JSON = 'data/live_model_PVDB.json' # Pick a proper time ISOTIME = '2021-04-13T15:14:00.000000-07:00'

In [3]:

# Get starting PVDB
prefix = ''
pvdb = json.load(open(PVDB_JSON))

# Get starting PVDB prefix = '' pvdb = json.load(open(PVDB_JSON))

In [4]:

# Add some extras for fun
extra_pvs = ['BMLN:LI21:235:MOTR',
 'BMLN:LI24:805:MOTR',
 'ACCL:LI22:1:PDES',
 'ACCL:LI25:1:PDES']
for pv in extra_pvs:
    pvdb[pv] = {}

# Add some extras for fun extra_pvs = ['BMLN:LI21:235:MOTR', 'BMLN:LI24:805:MOTR', 'ACCL:LI22:1:PDES', 'ACCL:LI25:1:PDES'] for pv in extra_pvs: pvdb[pv] = {}

In [5]:

# Optional: update from live EPICS
# import epics
# 
# pvnames = list(pvdb)
# vals = epics.caget_many(list(pvdb))
# pvdb = {}
# for name, val in zip(pvnames, vals):
#     pvdb[name] = {'value':val}
#

# Optional: update from live EPICS # import epics # # pvnames = list(pvdb) # vals = epics.caget_many(list(pvdb)) # pvdb = {} # for name, val in zip(pvnames, vals): # pvdb[name] = {'value':val} #

In [6]:

# Optional: 

# Open an SSH tunnel in a terminal like:
# ssh -D 8080 <SLAC username>@<SLAC machine>
# And then set:
os.environ['http_proxy']='socks5h://localhost:8080'
os.environ['HTTPS_PROXY']='socks5h://localhost:8080'
os.environ['ALL_PROXY']='socks5h://localhost:8080'

# Optional: # Open an SSH tunnel in a terminal like: # ssh -D 8080 @ # And then set: os.environ['http_proxy']='socks5h://localhost:8080' os.environ['HTTPS_PROXY']='socks5h://localhost:8080' os.environ['ALL_PROXY']='socks5h://localhost:8080'

In [7]:

# Update
new_pvdata = lcls_archiver_restore(list(pvdb), ISOTIME)
for k, v in new_pvdata.items():
#    print(pvdb[k]['value'], v)
    if v is None:
        print(k, 'Bad value:', v)
    else:
        pvdb[k]['value'] = v

# Update new_pvdata = lcls_archiver_restore(list(pvdb), ISOTIME) for k, v in new_pvdata.items(): # print(pvdb[k]['value'], v) if v is None: print(k, 'Bad value:', v) else: pvdb[k]['value'] = v

Requesting: http://lcls-archapp.slac.stanford.edu/retrieval/data/getDataAtTime?at=2021-04-13T15:14:00.000000-07:00&includeProxies=true
Warning: Missing PV: SBST:LI20:1:PHAS
Warning: Missing PV: GUN:IN20:1:GN1_AAVG
Warning: Missing PV: GUN:IN20:1:GN1_PAVG
Warning: Missing PV: ACCL:IN20:300:L0A_AAVG
Warning: Missing PV: ACCL:IN20:300:L0A_PAVG
Warning: Missing PV: ACCL:IN20:400:L0B_AAVG
Warning: Missing PV: ACCL:IN20:400:L0B_PAVG
Warning: Missing PV: ACCL:LI21:1:L1S_AAVG
Warning: Missing PV: ACCL:LI21:1:L1S_PAVG
Warning: Missing PV: ACCL:LI21:180:L1X_AAVG
Warning: Missing PV: ACCL:LI21:180:L1X_PAVG
KLYS:LI24:61:PHAS Bad value: None
KLYS:LI25:11:PHAS Bad value: None
KLYS:LI25:21:PHAS Bad value: None
KLYS:LI25:31:PHAS Bad value: None
KLYS:LI25:41:PHAS Bad value: None
KLYS:LI25:51:PHAS Bad value: None
KLYS:LI25:61:PHAS Bad value: None
KLYS:LI25:71:PHAS Bad value: None
KLYS:LI25:81:PHAS Bad value: None
KLYS:LI26:11:PHAS Bad value: None
KLYS:LI26:21:PHAS Bad value: None
KLYS:LI26:41:PHAS Bad value: None
KLYS:LI26:51:PHAS Bad value: None
KLYS:LI26:61:PHAS Bad value: None
KLYS:LI26:71:PHAS Bad value: None
KLYS:LI26:81:PHAS Bad value: None
KLYS:LI27:11:PHAS Bad value: None
KLYS:LI27:21:PHAS Bad value: None
KLYS:LI27:41:PHAS Bad value: None
KLYS:LI27:51:PHAS Bad value: None
KLYS:LI27:81:PHAS Bad value: None
KLYS:LI28:11:PHAS Bad value: None
KLYS:LI28:21:PHAS Bad value: None
KLYS:LI28:31:PHAS Bad value: None
KLYS:LI28:41:PHAS Bad value: None
KLYS:LI28:51:PHAS Bad value: None
KLYS:LI28:61:PHAS Bad value: None
KLYS:LI28:71:PHAS Bad value: None
KLYS:LI28:81:PHAS Bad value: None
KLYS:LI29:11:PHAS Bad value: None
KLYS:LI29:31:PHAS Bad value: None
KLYS:LI29:41:PHAS Bad value: None
KLYS:LI29:51:PHAS Bad value: None
KLYS:LI30:31:PHAS Bad value: None
KLYS:LI30:41:PHAS Bad value: None
KLYS:LI30:51:PHAS Bad value: None
KLYS:LI30:61:PHAS Bad value: None

In [8]:

# Dump to file for safekeeping
outfile = f'data/live_model_PVDB-{ISOTIME}.json'
json.dump(pvdb, open(outfile, 'w'))

# Dump to file for safekeeping outfile = f'data/live_model_PVDB-{ISOTIME}.json' json.dump(pvdb, open(outfile, 'w'))

SimpleServer from pcaspy¶

This following is adapted from: https://pcaspy.readthedocs.io/en/latest/tutorial.html

In [9]:

from pcaspy import Driver, SimpleServer

from pcaspy import Driver, SimpleServer

---------------------------------------------------------------------------
ModuleNotFoundError                       Traceback (most recent call last)
Input In [9], in <cell line: 1>()
----> 1 from pcaspy import Driver, SimpleServer

ModuleNotFoundError: No module named 'pcaspy'

In [10]:

class myDriver(Driver):
    def __init__(self):
        super(myDriver, self).__init__()
        
    def getParam(self, reason):
        #print('myDriver.getParam', reason) 
        return super().getParam(reason)

class myDriver(Driver): def __init__(self): super(myDriver, self).__init__() def getParam(self, reason): #print('myDriver.getParam', reason) return super().getParam(reason)

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Input In [10], in <cell line: 1>()
----> 1 class myDriver(Driver):
      2     def __init__(self):
      3         super(myDriver, self).__init__()

NameError: name 'Driver' is not defined

In [12]:

server = SimpleServer()
server.createPV(prefix, pvdb)
driver = myDriver()

server = SimpleServer() server.createPV(prefix, pvdb) driver = myDriver()

In [ ]:

while True:
    # process CA transactions
    server.process(0.1)

while True: # process CA transactions server.process(0.1)

In [14]:

# cleanup
os.remove(outfile)

# cleanup os.remove(outfile)