Using Expect to run C-Gate commands

A simple way to create a poor man's Homegate is to use Expect/Tcl scripts... for Windows users, download the binaries from http://bmrc.berkeley.edu/people/chaffee/expectnt.html

... then you can automate commands to C-Gate by writing the appropriate scripts... for example the following switches off my desk lights by connecting to my c-gate service running on my linux server (bart)...

# define c-gate server parameters
set hostname "bart"
set port "20023"
# define cgate v2.3.25 (build 2057) telnet response
set cgate_prompt "build 2057"
spawn telnet $hostname $port
expect -re "$cgate_prompt" {
# send c-gate command - turn off lights
exp_send "off 254/56/63\r"
}
expect "200 OK:"
exp_send "exit\r"
exp_send_user "Light Switched OFF"

... if you save the above as a file (say light_off.tcl), then pass into Expect on the command line you can automate the execution eg. create a Windows desktop icon to the runtime (tclsh80.exe) and pass in the path to the expect script eg. on my system this is -

"C:\Program Files\Expect-5.21\bin\tclsh80.exe" "C:\Program Files\Expect-5.21\light_off.tcl"

Choose your favorite icon, and away you go.

... another example, to set lights to 50% over 2 sec, with a bit of error handling...

set hostname "bart"
set port "20023"
set cgate_prompt "build 2057"
spawn telnet $hostname $port
expect -re "$cgate_prompt" {
exp_send "ramp 254/56/63 50% 2s\r"
exp_send_user "sent c-gate command\n"
} eof {
exp_send_user "could not connect to $hostname\n"
}
expect "200 OK:"
exp_send "exit\r"
exp_send_user "Light Switched On 50%"

 

Thanks ramon
Exactly the idea I need to inspire me.

I might try this in python and add on a web UI to it and away we go....

 

Just in case anyone was wondering the same, I have a basic python script working using the telnetlib module:

Code:

#!/usr/bin/python

import telnetlib
host = "cgatehost"
port = "20023"
telnet  = telnetlib.Telnet(host,port)
stuff = telnet.read_until("\n")
print stuff
telnet.write("project list\n")
stuff = telnet.read_until("\n")
print stuff
telnet.close()

Something to get people started.