rTorrent and libTorrent

Just a quick update: mancub has written a tutorial for setting up XMLRPC in lighttpd and using that with rTorrent and a GUI of your choice:
http://www.wl500g.info/showthread.php?t=12110

There are several GUI's, google for "rtorrent gui" or see the wikipedia page. I use rtGui on my desktop machine, I've set it to connect to lighttpd on the router over LAN. It allows you to add torrent files too! But you'll need a webserver on your desktop too for rtGui (I run Linux on the desktop as well so it wasn't much of a problem). I have no idea how well rtGui runs on a webserver installed on Windows.

So, now I have rtorrent with XMLRPC connected to lighttpd, both on the router, and the GUI on the desktop, which makes sense, because usually these clients are based on PHP or other stuff that is too heavy for the router.

The only problem left for me now is to figure out how to obtain a simple lightweight command line xmlrpc client. The xmlrpc-c package apparently has only the library. The purpose is to be able to query rtorrent for total bytes transferred up/down from a shell script and input that data into RRDTool. I already got graphs going that show total bytes transferred in/out of the route, it would be very interesting to be able to see how much of that is P2P.

I couldn't compile the xmlrpc client from the xmlrpc-c source package, got all kinds of errors until I gave up. Another possibility was to write a client in PHP but it runs slow as hell; plus PHP on the Asus doesn't have xmlrpc libs and I'd have to use all kinds of third party libs and it gets really annoying.

So the hell with all the xmlrpc crap. I figured out what lighttpd expects to receive at the special "/RPC2" url you set up (see mancub's tutorial). Which is this:

Code:

---

<?xml version="1.0" encoding="iso-8859-1"?>
<methodCall>
<methodName>d.multicall</methodName>
<params>
 <param>
  <value>
  <string>main</string>
  </value>
 </param>
 <param>
  <value>
  <string>d.get_down_total=</string>
  </value>
 </param>
 <param>
  <value>
  <string>d.get_up_total=</string>
  </value>
 </param>
</params>
</methodCall>

---

To make use of it, you put it in a file, let's call it "post.txt" then you can simply use wget (ipkg install wget) like this:

Code:

---

wget -T10 -q --no-check-certificate --post-data=post.txt -O - http://localhost/RPC2

---

Replace localhost/RPC2 with the address you've set up your lighttpd with. -T10 means to timeout after 10 seconds. -q means to be quiet (no progress bar). --no-check-certificate is useful if your lighttpd uses SSL. --post-data tells wget where to get the stuff above. -O - means to output what it gets back on the console, so you can pipe it to something else, replace - with a file name if you like that better.

This is what wget should return if everything was set up properly:

Code:

---

<?xml version="1.0" encoding="UTF-8"?>
<methodResponse>
<params>
<param><value><array><data>
<value><array><data>
<value><i8>4271258199</i8></value>
<value><i8>1437056179</i8></value>
</data></array></value>
<value><array><data>
<value><i8>4271258199</i8></value>
<value><i8>1437056179</i8></value>
</data></array></value>
<value><array><data>
<value><i8>4271258199</i8></value>
<value><i8>1437056179</i8></value>
</data></array></value>
<value><array><data>
<value><i8>4271258199</i8></value>
<value><i8>1437056179</i8></value>
</data></array></value>
</data></array></value></param>
</params>
</methodResponse>

---

Obviously, the values will be different each time you do this. But you'll notice that all four value sets are identical, so you can use only the first set. I dunno why rtorrent does that but I had 4 torrents running so it may be that.

Don't worry, the values you get this way are good. I've checked against the overall WLAN transfer numbers and against the limits I've set in rtorrent, and they match.

So, all you need to do next is use shell commands to extract those two values from there, then you can use them with rrdtool or whatever.

If anybody has some cool sed or awk magic they can use to extract them, please tell us. For now, all I've been able to come up with is this:

Code:

---

wget bla bla bla |\
grep i8|sed 's/[^0-9]//g'|tr '[:space:]' ' '|awk '{print $1":"$2}'

---

This will print the numbers separated by colons, good to be sent directly to rrdtool. If you want something else adjust as needed.

What happens here: I select only the lines with "i8" on them, 'cause I know they have the numbers. Then I strip everything but the digits. Then I put everything on the same line. Then I extract the first and second things on the line.

Quote:

---

Originally Posted by al37919

P.S. This script has 1 small bug/feature. An extra screen window with /bin/sh is started which can be afterwards exited manually. Up to now nobody knows how to eliminate it :(

---

Hey, al37919, when you do "screen -S rtorrent -X screen rtorrent" what you're doing is creating a new screen window window with the rtorrent program running on it. There is window #0 and then you are creating window #1 with rtorrent attached. If you want to get rid of that extra window (window #0), you can do two things:

1) Send an stuff command to screen, with rtorrent and the carriage return code (Control-M). With -p 0 you select the window #0 and stuff sends the parameter string to that window:

Code:

---

screen -S rtorrent -p 0 -X stuff 'rtorrent^M'

---

2) Send the kill command to the same window:

Code:

---

screen -S rtorrent -p 0 -X kill

---

The second command can also be used to kill the window after rtorrent exits, if you want to.

Hi! Thanks for the advice, I've somehow missed this message. Now I tested both possibilities:

Thing #1 unfortunately is not completely effective. Using it we really have only single window #0 in the session, however the junk /bin/sh process is still sitting in the 'ps aux' output. Killing of this /bin/sh naturally kills both rtorrent and screen.

Thing #2 seems to solve the issue. If we add it at the end of the d_start() function we get rtorrent started without annoying process in the memory. Exiting of the rtorrent results in termination of teh screen session.

Thanks a lot again,
al