Switching FoxyProxy Profiles using Script

FoxyProxy is a useful extension to Firefox, but I’m always having to switch profiles back and forth as I take my laptop from work to home, and vice versa. I experimented with proxy PAC files without any success (mainly because laptops have multiple network adapters and the PAC scripts only detect your first IP address). Plus, as far as I can tell, PAC files are checked for every single HTTP request which must be a hit on browser performance.

Anyway, what I decided to do was directly modify the FoxyProxy config file before Firefox was run, and this would then select which FoxyProxy profile was used. The script below detects the host of something on my local network (which doesn’t exist at work) and switches accordingly. You could get it to switch on anything you like, but this works for me.

runfirefox.vbs

Set WshShell = WScript.CreateObject("WScript.Shell")

' Code to determine where you are and switch profiles accordingly
if (Ping("somehost") = "201.69.34.132") then
	ModifyFoxyProxy("3402440320")
else 
	ModifyFoxyProxy("patterns")
end if

' Run Firefox - this uses a specific profile.. your command line can simply exclude it
ReturnCode  = WshShell.Run("""C:\Program Files\Mozilla Firefox\firefox.exe"" -profile ""z:/firefox/profiles/qtxjee58.default""", 6, False)



sub ModifyFoxyProxy(sProfile) 
	' Path to your foxyproxy.xml file
	xmlfile="Z:\Firefox\Profiles\qtxjee58.default\foxyproxy.xml"
	outfile="Z:\Firefox\Profiles\qtxjee58.default\foxyproxy.xml"
	set oparser=createobject("msxml2.domdocument")
	with oparser
	    .async=false
	    .validateOnParse=false
	    .resolveExternals=false
	    .load xmlfile
	end with
	    
	if oparser.parseerror.errorcode<>0 then
	    wscript.echo "xml file " & xmlfile & " is not well-formed." & vbcrlf & "Operation aborted."
	    wscript.quit 999
	end if
	
	set oroot=oparser.documentElement
	oroot.setAttribute "mode", sProfile
	oparser.save outfile
	    
	set oparser=nothing 

end sub


function Ping(strHost)

    dim objPing, objRetStatus

    set objPing = GetObject("winmgmts:{impersonationLevel=impersonate}").ExecQuery ("select * from Win32_PingStatus where address = '" & strHost & "'")

    for each objRetStatus in objPing
        if IsNull(objRetStatus.StatusCode) or objRetStatus.StatusCode<>0 then
    		Ping = ""
            'WScript.Echo "Status code is " & objRetStatus.StatusCode
        else
            'Ping = True
            'Wscript.Echo "Bytes = " & vbTab & objRetStatus.BufferSize
            'Wscript.Echo "Time (ms) = " & vbTab & objRetStatus.ResponseTime
            'Wscript.Echo "TTL (s) = " & vbTab & objRetStatus.ResponseTimeToLive
            Ping = objRetStatus.ProtocolAddress 
        end if
    next
    
end function