Interface Gateway Help Requested

I'm not familiar with Python I'm afraid. It hasn't changed for quite a while and as Karl says it works on test clients. Granted SimSig should not throw an access violation so I'd be interested to work out how that is being generated.

Again, I'm a bit rusty on this but the "Expecting CONNECT" message is because SimSig is not seeing the verb "CONNECT" with the key/value of "accept-version" and "1.1". Yet the Python code (which I'm not familiar with) appears to send that, and Karl says it works. So I'm confused. The only thing that stands out for me is the body='accept-version:1.1' which reads to me as the body, not the header text.

As if it's sending:
CONNECT

otherbodytext
accept-version:1.1
^@

Instead of:
CONNECT
accept-version:1.1

otherbodytext
^@

(the double carriage return signifies the end of headers and the start of the body)

Maybe it's as simple as:
conn.start()
conn.connect()
conn.subscribe(etc)

(from https://stackoverflow.com/questions/6234630/activemq-how-to-configure-to-work-with-stomp-in-python )

its likely we have a later version of the library than others. We will have to wait for headshot119 to see if that is the case. If we know the working version number then we can install the older versions

Likewise I tried it using both python 2.7 and 3.7 venvs and I got the same access violation and no response from the gateway.

from stompest.config import StompConfig
from stompest.protocol import StompSpec, frame
from stompest.sync import Stomp

CONFIG = StompConfig('tcp://localhost:51515', version=StompSpec.VERSION_1_1)
QUEUE = '/topic/TD_ALL_SIG_AREA'

if __name__ == '__main__':
client = Stomp(CONFIG)
client.connect()
# client.subscribe(QUEUE, {StompSpec.ACK_HEADER: StompSpec.ACK_CLIENT_INDIVIDUAL})
a = frame.StompFrame(command='SUBSCRIBE', rawHeaders=[('id', '0'), ('destination', '/topic/TD_ALL_SIG_AREA'),('ack', 'auto')])
client.sendFrame(a)
while True:
frame = client.receiveFrame()
print(dict(frame))
client.disconnect()

pip install stompest

Quite excited by the input control on Headshot119's Github - connecting as a SimSig client rather than to the interface. Might it be possible to get level crossing status out that way?

DonRiver in post 116520 said:

Quite excited by the input control on Headshot119's Github - connecting as a SimSig client rather than to the interface. Might it be possible to get level crossing status out that way?

It's great to see the interest in this. I would caution against using the client interface instead of the Gateway as the former uses indexes for objects and compressed fields, which can change between different versions of the same sim, whereas the Gateway uses names (human friendly as well as computer friendly). IIRC there was a slight change to the protocol just last week for clients.

You can also ask for extra things in the Gateway - usually a relatively simple task for us.

Thanks very much Sam - I could get your stompest example to work!

Would suggest `print frame.body` rather than `print(dict(frame))` as `frame.body` gives clean json while `dict` gives… I'm not sure what exactly?

I'm trying and failing to pipe the stompest example into jq so I can format and filter the json - but the problem's probably my inexpertise with bash.

Short of building an entire NX panel (nice as that would be) I'd like to make something to help me manage trains approaching level crossings. Got North-East Scotland in mind particularly here.

Stage 1 is to write a jq filter which presents a console message when specific track sections/berths become occupied. This can run in the console on the second monitor.

Stage 2 would be a small hardware panel which indicate specific track circuits with LEDs - and if it could be wrangled, also show the status of the crossings and with hardware inputs to control them?

Stage 3 would be a scaled-down NX panel covering some manageable section of the simulation. Strips of addressable RGB LEDs might be a simple and cheap way of representing track occupancy and route selection in bulk.

Quite excited by the input control on Headshot119's Github - connecting as a SimSig client rather than to the interface. Might it be possible to get level crossing status out that way?