Rough writeup of necessary functionality for Barco control, main features work (polish with error handling pending)

barco_telnet/barco_telnet_control.py

@@ -0,0 +1,72 @@
+import asyncio
+import aiomqtt
+import telnetlib3
+
+cmdMap = {
+    'POWER': 'POWR',
+    'SHUTTER': 'PMUT',
+    'FREEZE': 'FRZE'
+}
+reverseCmdMap = {v: k for k, v in cmdMap.items()}
+
+def parse_barco_response(raw: str):
+    raw = raw[1:-1]  # strip square brackets
+    #print(raw)
+    if raw.startswith("ERR"):
+        return None  # TODO parse type error - "disabled control" is special case
+    cmd, status = raw.split("!", maxsplit=2)
+    #print(cmd + " " + status)
+    cmd = reverseCmdMap[cmd]
+    status = 'ON' if status == '01' else 'OFF'
+    return cmd, status
+
+
+async def barco_telnet_command(client, writer):
+    await client.subscribe("p1/projectors/main/#")
+    async with client.messages() as msgs:
+        async for mesg in msgs:
+            if mesg.topic.matches('p1/projectors/main/command/+'):
+                cmd = mesg.topic.value.split("/")[-1]
+                val = '1' if mesg.payload.decode() == 'ON' else '0'
+                barcoCmd = f"[{cmdMap[cmd]}{val}]"
+                print("Received: [" + mesg.topic.value + "] payload: [" + mesg.payload.decode() + "]")
+                print("Sending command to Barco: " + barcoCmd)
+                writer.write(barcoCmd)
+
+
+async def barco_telnet_read_status(client, reader):
+    while True:
+        output = await reader.readuntil(b']')
+        raw_response: str = output.decode().strip()  # strip not necessary? needed for local netcat testing though
+        print("Received: " + raw_response + " from Barco")
+        parsed = parse_barco_response(raw_response)
+        if parsed == None:
+            continue  #TODO alert for errors
+        print(f"Updating topic [{parsed[0]}] with value [{parsed[1]}]")
+        await client.publish(f"p1/projectors/main/status/{parsed[0]}", payload=parsed[1])
+
+
+async def barco_telnet_query_status(writer):
+    while True:
+        for val in cmdMap.values():
+            print(f"Querying Barco with: [{val}?]")
+            writer.write(f"[{val}?]" + '\r\n')  # TODO test if funny CRLF necessary (it probably gets ignored)
+            await asyncio.sleep(1)  # sleep between writes necessary, otherwise it gets confused.
+            # simultaneous commands from control could break this? TODO fix later
+        await asyncio.sleep(1000)  # TODO find appropriate period
+
+
+async def shell(reader, writer):
+    async with aiomqtt.Client('localhost', 1883) as client:
+        task_status_query = asyncio.create_task(barco_telnet_query_status(writer))
+        task_status_reader = asyncio.create_task(barco_telnet_read_status(client, reader))
+        task_control = asyncio.create_task(barco_telnet_command(client, writer))
+        await asyncio.gather(task_status_query, task_status_reader, task_control)
+
+
+if __name__ == '__main__':
+    loop = asyncio.get_event_loop()
+    #coro = telnetlib3.open_connection('192.168.192.12', 3023, shell=shell)
+    coro = telnetlib3.open_connection('localhost', 1234, shell=shell)
+    reader, writer  = loop.run_until_complete(coro)
+    loop.run_until_complete(writer.protocol.waiter_closed)