bluesky-hwproxy 2022.8.0

Proxy for reading bluesky hardware over ZMQ interface.

Bluesky Hardware Proxy

This is a proxy server to provide access to certain bluesky device methods over a zmq interface. The interface is based directly on the zmq interface of bluesky-queueserver, so an identical client (with a different address) can be used. For convenience, a version of zmq_single_request with the default address of tcp://localhost:60620 is provided as bluesky_hwproxy.comms.zmq_single_request.

Starting a server

start-hwproxy-server is an entry point provided to start up an instance of hwproxy. It accepts the same parameters for specifying the environment that contains device objects as start-re-manager from bluesky-queueserver.

for example:

$ start-hwproxy-server --startup-script ./startup.py
$ start-hwproxy-server --startup-module ophyd.sim
$ start-hwproxy-server --startup-dir ./startup/

Note that at present, --startup-profile is not connected, though will be in the near future.

Connecting via python

from bluesky_hwproxy.comms import zmq_single_request

devices = zmq_single_request("list")[0]["result"]

describe = zmq_single_request("describe", {"device":devices[-1]})[0]["result"]

Connecting via cli

We provide a hwproxy command line program to allow interfacing with the hwproxy server

Commands to interact with the server itself:

$ hwproxy list # List available hardware as string keys, one per line
motor1
motor2
det

$ hwproxy reload # reload available devices

The following print JSON response to the terminal:

$ hwproxy read <device>
$ hwproxy describe <device>
$ hwproxy config read <device>
$ hwproxy config describe <device>
$ hwproxy hints <device>

Output is colorized when run from an interactive shell, plain text when e.g. piped.

Finally, we allow checking if a set position is valid:

$ hwproxy check <device> <value>
true

The result is simply true or false printed to the terminal.

<value> can be any json encoded string (most of the time it is a simple float, however pseudopositioners and specialized hardware may use lists, etfc.