katsdptelstate 0.6

Getting Started

You will need a relatively recent version of Redis installed (2.8.9 or newer).

• macOS: brew install redis

• Ubuntu: apt-get install redis-server

Then pip install katsdptelstate and run a local redis-server. If you also want to load RDB files, do pip install katsdptelstate[rdb].

A Simple Example

import time
import katsdptelstate

# Connect to an actual Redis server
telstate = katsdptelstate.TelescopeState('localhost:6379')
# Or use a fake Redis instance (key/values stored in memory, useful for testing)
telstate = katsdptelstate.TelescopeState()
# Load dump file into Redis if katsdptelstate is installed with [rdb] option
telstate.load_from_file('dump.rdb')

# Attribute / dict style access returns the latest value
telstate.add('n_chans', 32768)
print(telstate.n_chans)
print(telstate['n_chans'])

# List all keys (attributes and sensors)
print(telstate.keys())

# Sensors are timestamped underneath
st = time.time()
telstate.add('n_chans', 4096)
et = time.time()
telstate.add('n_chans', 16384)
# Time ranges can be used and are really fast
telstate.get_range('n_chans', st=st, et=et)
# Add an item 10 seconds back
telstate.add('n_chans', 1024, ts=time.time() - 10)

# Attributes cannot be changed (only deleted)
telstate.add('no_change', 1234, immutable=True)
# Adding it again is OK as long as the value doesn't change
telstate.add('no_change', 1234, immutable=True)
# Will raise katsdptelstate.ImmutableKeyError
telstate.add('no_change', 456)