Metadata-Version: 2.1
Name: liteserver
Version: 1.0.5
Summary: Lightweight control system for scientific instruments. Like EPICS but much simpler
Home-page: https://github.com/ASukhanov/liteServer
Author: Andrei Sukhanov
Author-email: sukhanov@bnl.gov
License: MIT
Description: # liteserv
        Very Lightweight Data Object Server. 
        It hosts Lite Data Objects (**LDO**, analog of process variables in 
        EPICS) and provides info/set/get/read/subscribe remote access to them using 
        UDP protocol. Data encoding is implemented using UBJSON specification, 
        which makes it very fast and efficient.
        
        ### Data logging and retrieving
        Data objects can be logged and retrieved using an **apstrim** package (https://pypi.org/project/apstrim).
        
        ### Bridged usage
        To monitor and control liteserv-served devices from an existing architecture 
        one can use or build a simple bridge:
        ##### A bridge for RHIC ADO Control architecture is liteServerMan.py
            liteServerMan.py -HmyHost myADO.
        An ADO manager liteServerMan.py connects to a liteServer, running on myHost and 
        creates the myADO. 
          - All input LDOs are translated to myADO input parameters.
          - All output parameters of the myADO are translated to LDOs.
        
        ##### For EPICS Control architecture
        The bridge liteServer-EPICS can be developed using a python-based implementation of IOC, for example:
        [caproto](https://nsls-ii.github.io/caproto/)
        
        ### Features
         - Simplicity. The network protocol is **UDP**, error correction of 
        late/missing/mangled data is
        implemented. The serialization protocol is **UBJSON**: binary, easier than RPC, 
        provides all JSON features. All this makes it possible to implement liteServer 
        on a CPU-less FPGA.
         - Low latency, connection-less.
         - Supported requests:
           - **info()**, returns dictionary with information on requested LDOs and 
           parameters
           - **get()**, returns dictionary of values of requested LDOs and parameters
           - **read()**, returns dictionary of changed readable (non-constant) 
           parameters of requested LDOs
           - **set()**, set values or attributes of requested LDO parameters
           - **subscribe(callback)**, subscribe to a set of the objects, if any object 
        of the requested LDOs have been changed, the server will publish the changed 
        objects to client and the callback function on the client will be invoked.
         - Multidimensional data (numpy arrays) are supported.
         - Access control info (username, program name) supplied in every request
         - Name service
           - file-based
           - network-based using a dedicated liteServer  (not commissioned yet)
         - Basic spreadsheet-based GUI: **pypet**
         - Architectures. All programs are 100% python. Tested on Linux and Windows.
         - Supported applications:
           - [Image analysis](https://github.com/ASukhanov/Imagin)
           - [Data Logger](https://github.com/ASukhanov/apstrim)
        
        ### Key Components
        - **liteServer**: Module for building liteServer applications.
        - **liteAccess**: Module for for accessing the Process Variables from a liteServer.
        - **liteCNS.py**: Name service module, it provides file-based (**liteCNS.yaml**) or network-based name service (**liteCNSserver.py**).
        
        ### Supportted devices
        Server implementations for various devices are located in .device sub-package. 
        A device server can be started using following command:
        
            python3 -m liteserv.device.<deviceName> <Arguments>
        
        - **device.liteScaler**: test implementation of the liteServer
        , supporting 1000 of up/down counters as well as multi-dimensional arrays.
        - **device.litePeakSimulator**: Waveform simulator with multiple peaks and
        a background noise.
        - **device.liteVGM**: Server for multiple gaussmeters from AlphaLab Inc.
        - **device.liteUSBCam**: Server for USB cameras.
        - **device.liteUvcCam**: Server for USB cameras using UVC library, allows for 
        pan, zoom and tilt control.
        - **device.liteWLM**: Server for Wavelength Meter WS6-600 from HighFinesse.
        - **device.liteLabjack**: LabJack U3 analog and digital IO module.
        - **device.senstation**: Server for various devices, connected to Raspberry Pi
        GPIOs: 1-wire temperature sensor, Pulse Counter, Fire alarm and Spark detector,
        Buzzer, RGB LED indicator, OmegaBus serial sensors. Coming soon: NUCLEO-STM33 
        mixed signal MCU boards, connected to Raspberry Pi over USB.
        - **device.liteGQ**: Geiger Counter and a gyro sensor GMC-500 from GQ Electronics.
        
        ### Installation
        Python3 should be 3.6 or higher.
        
            python3 pip install liteserver
        
        Additional libraries may be required for specific devices.
        
        ## Examples
        Most convenient way to test base class functionality is by using **ipython3**, 
        
        Start a server liteScaler on a local host:
        
            python3 -m liteserver.device.liteScaler -ilo -s2
            ipython3
        
        ```python
        from liteserver import liteAccess as LA 
        from pprint import pprint
        
        Host = 'localhost'
        LAserver = Host+':server'
        LAdev1   = Host+':dev1'
        LAdev2   = Host+':dev2'
        
        #``````````````````Programmatic way, using Access`````````````````````````````
        # Advantage: The previuosly created PVs are reused.
        list(LA.Access.info((Host+':*','*')))# list of all devices on the Host
        LA.Access.info((LAserver,'*'))
        LA.Access.get((LAserver,'*'))
        LA.Access.set((LAdev1,'frequency',[2.0]))
        LA.Access.subscribe(LA.testCallback,(LAdev1,'cycle'))
        LA.Access.unsubscribe()
        #,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,	
        #``````````````````Object-oriented way````````````````````````````````````````
        allServerParameters = LA.PVs((LAserver,'*'))
        pprint(allServerParameters.info())
        pprint(allServerParameters.get())# get all parameters from device LAserver
        # get all readable parameters from device Scaler1:server, which have been 
        # modified since the last read:
        pprint(allServerParameters.read())
        
        allDev1Parameters = LA.PVs((LAdev1,'*'))
        print(allDev1Parameter.info())
        
        server_performance = LA.PVs((LAserver,'perf'))
        pprint(server_performance.info())
        pprint(server_performance.get())
        # simplified get: returns (value,timestamp) of a parameter 'perf' 
        pprint(server_performance.value)
        
        server_multiple_parameters = LA.PVs((LAserver,('perf','run')))
        pprint(server_multiple_parameters.info())
        pprint(server_multiple_parameters.get())
        
        server_multiple_devPars = LA.PVs((LAdev1,('time','frequency')),(LAserver,('statistics','perf')))
        pprint(server_multiple_devPars.get())
        
        # setting
        dev1_frequency = LA.PVs((LAdev1,'frequency'))
        dev1_frequency.set([1.5])
        dev1_frequency.value
        dev1_multiple_parameters = LA.PVs([LAdev1,('frequency','coordinate')])
        dev1_multiple_parameters.set([8.,[3.,4.]])
        
        # subscribing
        ldo = LA.PVs([LAdev1,'cycle'])
        ldo.subscribe()# it will print image data periodically
        ldo.unsubscribe()# cancel the subscruption
        
        # test for timeout, should timeout in 10s:
        #,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
        #``````````````````Observations```````````````````````````````````````````````
            # Measured transaction time is 1.8ms for:
        LA.PVs([[['Scaler1','dev1'],['frequency','command']]]).get()
            # Measured transaction time is 6.4ms per 61 KBytes for:
        LA.PVs([[['Scaler1','dev1'],'*']]).read() 
        #``````````````````Tips```````````````````````````````````````````````````````
        # To enable debugging: LA.PVs.Dbg = True
        # To enable transaction timing: LA.Channel.Perf = True
        ```
        
Platform: UNKNOWN
Classifier: License :: OSI Approved :: MIT License
Classifier: Programming Language :: Python :: 3
Classifier: Programming Language :: Python :: 3.7
Description-Content-Type: text/markdown
