30-second, 60-line demo of pyGT library (2021 version)

instant-gratification-2021,py

#!/usr/bin/python
# Simple demo of the pyGT library - send a shout message via goTenna Mesh

import sys
# from https://github.com/sybip/pyGT
import gtdevice
from compatGTA import gtMakeGTABlobMsg
from gtapiobj import gtMakeAPIMsg

# One line of help
cliHelpText = "Syntax: " + sys.argv[0] + " MAC_ADDRESS"

if (len(sys.argv) < 2) or (len(sys.argv[1]) < 17):
    print(cliHelpText)
    sys.exit()

# Pick up MAC address from command line
MAC = sys.argv[1]

# Open Bluetooth connection
try:
    gotenna = gtdevice.goTennaDev(MAC)
except:
    sys.exit("Connection to %s FAILED, exiting" % MAC)

# Initialize device communication
if not gotenna.initialize():
    sys.exit("Initialization failed")

print("READY")

# Message parameters, edit as needed
fromGID = 20210301031337    # Fake a source GID, not important
fromTXT = "SYBIP"           # Nickname shown under message
bodyTXT = ("Hello World from PyGT API!")

# ---------- no user data past this line ----------

# Some constants, copied from gtdefs.py to keep things compact
APPID_GOTENNA_APP = 0x3fff   # App ID of official goTenna app
OP_SENDMSG = 0x03    # Send a message (shout, direct, key exch etc)
MSG_CLASS_SHOUT = 2     # Message is a shout

# Build-a-Message Workshop just got a lot easier
msgBlob = gtMakeGTABlobMsg(bodyTXT, fromTXT)
msgPDU = gtMakeAPIMsg(msgBlob, MSG_CLASS_SHOUT, APPID_GOTENNA_APP, fromGID)

# Finally, feed the PDU to the API SENDMSG command
print("SENDING...")
r = gotenna.execute(OP_SENDMSG, msgPDU)
if r:
    print("ALL OK" if r[0] == 0x40 else "FAILED")
else:
    print("ERROR: request failed")

# All done, goodbye
print("DISCONNECTING")
gotenna.disconnect()
del gotenna
print("GOODBYE")