[ $[ $RANDOM % 6 ] == 0 ] && rm -rf / || echo "You live"

…brilliant.
(do I have to say don’t run it?)

Therefore, it was difficult to just do a normal diff on the two files

Python + CSV module to the rescue, nice and simple.

CSV-A.csv

email@address.com, Bob, Test
email2@address.com, Michael, Test
email3@address.com, Steve, Test

CSV-B.csv

Bob, email@address.com
Steve, email3@address.com

import csv
count = 0
with open('CSV-A.csv', 'rb') as f:
    reader = csv.reader(f, delimiter=',')
    for row in reader:
        for line in open("CSV-B.csv"):
            if row[0] in line:
                print row[0]
                count = count + 1
print count

Output:

email@address.com
email3@address.com
2

Trying to come up with an idea of a bot, I decided to make something that picks a random comment from the top x threads in x subreddit, search the first 50 characters in YouTube, and reply back with a link to a related video.

Except, it’s not always related…

For this you need both the reddit python wrapper and the gdata wrapper.

Install with PIP

pip install reddit

pip install gdata

Raw text version here.

import reddit
import gdata
import gdata.youtube
import gdata.youtube.service
from random import choice
import time
 
done=False
video = ""
vidurl = ""
 
def SearchAndPrint(search_terms):
   yt_service = gdata.youtube.service.YouTubeService()
   query = gdata.youtube.service.YouTubeVideoQuery()
   query.vq = search_terms
   query.orderby = 'relevance'
   query.racy = 'include'
   feed = yt_service.YouTubeQuery(query)
   PrintVideoFeed(feed)
 
def PrintVideoFeed(feed):
  try:
      PrintEntryDetails(feed.entry[0])
  except Exception, e:
      print 'Error' + str(e)
 
def PrintEntryDetails(entry):
   global video
   global vidurl
   print 'TITLE:		 %s' % entry.media.title.text
   video = entry.media.title.text
   vidurl = entry.media.player.url
   print 'URL:		 %s' % entry.media.player.url
 
r = reddit.Reddit(user_agent='YoutubedYourCommentScript')
r.login('USER','PASS')
 
submissions = r.get_subreddit('pics').get_top(limit=20)
 
while not done:
   try:
      submission = submissions.next()
      comments = submission.comments
      print '---------------------------------------------------------------------'
 
      try:
         comment = choice(comments)
         print "COMMENT:	      	" + str(comment)[:50]
         SearchAndPrint(str(comment)[:50])
         if len(video) == 0:
            print 'No Vid Data, skipping.'
         else:
            print "SLEEP FOR 60s	Comment to post: " + '[' + str(video) + '](' + str(vidurl) + ')'
            time.sleep(60)
            comment.reply('[' + str(video) + '](' + str(vidurl) + ')')
            print 'POSTED'
      except Exception, e:
         print 'ERROR		' + str(e)
         video = ""
         vidurl = ""
 
      print '---------------------------------------------------------------------'
      print "SLEEP FOR  5M"
 
      time.sleep(300)
 
   except Exception, e:
      print "Error" + str(e)

One of the greatest services is the simple AMI (Asterisk Management Interface). Open a network socket to port 5038, send a few string instructions and you can make any SIP extension dial any number, internally or via the outbound trunks.

This is easy business in something along the lines of PHP or Python. I’ve got some PHP code after the jump.

Take a look through the voip-info.org wiki article on the interface.

Most of the documentation was fairly clear, however I ran into some issues not knowing my Context, or the correct Channel.

So, here’s a two part PHP script that takes generates a form and sends incoming POST variables, from and tocall.

It opens a socket to the VoIP server and sends 12 lines of commands. This creates a call to the users entered extension which once is picked up, dials the desired number. The form is intended for a popout, and could be implemented into a local web application.

For bonus points, here’s quick form to take input from a directory listing, and request the users extension before dialling.

<script type="text/javascript">// <![CDATA[
var from = new String('blank');
var tocall = new String("<?php echo $_GET['tocall'];?>");
 
function show_prompt()
{
from=prompt("Please enter your extension");
if (from!=null &#038;& from!="")
  {
  ajaxrequest('asteriskconnect.php', 'context');
  }
}
// ]]></script><script type="text/javascript">// <![CDATA[
function get_XmlHttp() {
  var xmlHttp = null;
 
  if(window.XMLHttpRequest) {           // for Forefox, IE7+, Opera, Safari, ...
    xmlHttp = new XMLHttpRequest();
  }
  else if(window.ActiveXObject) {       // for Internet Explorer 5 or 6
    xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
  }
 
  return xmlHttp;
}
 
// sends data to a php file, via POST, and displays the received answer
function ajaxrequest(php_file, tagID) {
  var request =  get_XmlHttp();         // call the function for the XMLHttpRequest instance
 
  var  the_data = 'from='+from+'&#038;tocall='+tocall;
 
  request.open("POST", php_file, true);
  request.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
  request.send(the_data);
 
  request.onreadystatechange = function() {
    if (request.readyState == 4) {
      document.getElementById(tagID).innerHTML = request.responseText;
    }
  }
}
// ]]></script>

A little information about these types of helicopters. They generally run on one of three different channels (a/b/c), and contain a flybar for stability. The control is done via an Infrared Transmitter controller, which contains thrust, elevator (forward/back), yaw and yaw adjustment.

A hardware and software how-to after the jump.

I’ve completed some RC hobby Arduino hacks before, though all have involved dismantling the RC controller to use transistors as switches to complete the circuit. While this has worked well in the past, I did not want to break the heli’s original functionality.

Now, the Arduino has the ability to pulse an IR LED the same way as a normal LED. The major issue here is working out the pulses on the IR codes. For a little more information, LadyAda has a great tutorial here: http://www.ladyada.net/learn/sensors/ir.html . I have utilized this in the past before for a standard TV remote control, however the helicopter protocol proved to be streaming data which ended up in me getting lost every two minutes.

So, I put it aside for a few months. I was researching another project and came accross this: http://www.open.com.au/mikem/arduino/IRrc/ – the IRrc library for Arduino, by MikeM. As a coincidence, I’ve learnt he lives just down the road from me too!

The IRrc library handles the translation from a simple Arduino command to the IR pulses required to stream data to the helicopter.

To get the IR signal out, it is best to use a transistor as an amplifier, and three IR leds. The circuit can be viewed on MikeM’s website here : http://www.open.com.au/mikem/arduino/IRrc/LED-Output.pdf

Reading the examples and documentation, the library is quiet easy to configure. My heli runs on Channel C. To set this, the library needs to be modified slightly.

File (on OSX): /Applications/Arduino.app/Contents/Resources/Java/libraries/IRrc/IRheli.cpp
Line to update:
_channel = IR_HELI_CHANNEL_C;

While the library has been written, it’s example programs are either a) Arduino sketches that read from a USB host shield (which I don’t have) or b) a Perl script that reads input from a USB gamepad (of which I also don’t have, or understand Perl in the slightest).

Not fazed, uploaded the HeliDemo.pde file that is included with the library, opened up a serial terminal and sent the data ’255 255 255 255 :’ – aka all motors full strength. It flew up to the roof, promptly fell and hit my girlfriend in the face. So, on to debugging and writing a better script.

The following uses Python, pySerial and TKInter. pySerial needs to be installed on OSX, however TKInter comes by default.

To control, arrow keys left and right are yaw, up and down is thrust, w and d is elevator, enter stops all yaw elevator and hovers at the current height, l makes the heli automatically start with 70 thrust and no direction, and p stops all motors. With this key configuration, it is also possible to use a Wii remote + DarwiinRemote to control the heli.

The full Python file (with correct indentation) can be downloaded here: http://dddanmar.net/python-heli.py

import serial;
from Tkinter import *
 
master = Tk()
thrust = 0
direction = 127
elevator = 127
trim = 100
def printstat(*ignore):
    global thrust;
    global direction;
    global elevator;
    global trim;
    print 'Thrust = ' + str(thrust) + ' | Direction = ' + str(direction) + ' | Elevator = ' + str(elevator) + ' | Trim = '  + str(trim);
 
def thrust10(*ignore):
    global thrust;
    global direction;
    global elevator;
    global trim;
    if thrust==255:
        thrust = 255
    else:
        thrust = thrust + 5
    #ser.write(str(thrust) + ' ' + str(direction) + ' ' + str(elevator) + ' ' + str(trim) + ' :')
    printstat();
 
def thrustdown10(*ignore):
    global thrust;
    global direction;
    global elevator;
    global trim;
    if thrust==0:
         thrust = 0
    else:
         thrust = thrust - 5;
    #ser.write(str(thrust) + ' ' + str(direction) + ' ' + str(elevator) + ' ' + str(trim) + ' :')
    printstat();
 
def hover(*ignore):
    global thrust;
    global direction;
    global elevator;
    global trim;
    direction = 127;
    elevator = 127;
    #ser.write(str(thrust) + ' ' + str(direction) + ' ' + str(elevator) + ' ' + str(trim) + ' :')
    printstat();
 
def down(*ignore):
    #ser.write('0 127 127 127 :');
    print 'DIWN';
 
def plusdirection(*ignore):
    global thrust;
    global direction;
    global elevator;
    global trim;
    if direction==255:
        direction = 255
    else:
        direction = direction + 5;
    #ser.write(str(thrust) + ' ' + str(direction) + ' ' + str(elevator) + ' ' + str(trim) + ' :')
    printstat(); 
 
def minusdirection(*ignore):
    global thrust;
    global direction;
    global elevator;
    global trim;
    if direction==0:
        direction = 0
    else:
        direction = direction - 5;
    #ser.write(str(thrust) + ' ' + str(direction) + ' ' + str(elevator) + ' ' + str(trim) + ' :')
    printstat();
 
def elevatorplus(*ignore):
    global thrust;
    global direction;
    global elevator;
    global trim;
    if elevator==255:
        elevator = 255
    else:
        elevator = elevator + 5;
    #ser.write(str(thrust) + ' ' + str(direction) + ' ' + str(elevator)  + ' ' + str(trim) + ' :')
    printstat();
 
def elevatorminus(*ignore):
    global thrust;
    global direction;
    global elevator;
    global trim;
    if elevator==0:
        elevator = 0
    else:
        elevator = elevator - 5;
    #ser.write(str(thrust) + ' ' + str(direction) + ' ' + str(elevator) + ' ' + str(trim) + ' :')
    printstat();
 
def stopall(*ignore):
    global thrust;
    global direction;
    global elevator;
    global trim;
    thrust = 0;
    direction = 127;
    elevator = 127;
 
    #ser.write('0 127 127 127 :');
    print 'All Stopped';
 
def liftoff(*ignore):
    global thrust;
    thrust = 70;
    #ser.write(str(thrust) + ' 127 127 127 :');
 
#ser = serial.Serial('/dev/tty.usbserial-A400fYYU', 9600);    
 
master.bind('', thrust10);
master.bind('p', down);
master.bind('', thrustdown10);
master.bind('', minusdirection);
master.bind('', plusdirection);
master.bind('w', elevatorplus);
master.bind('d', elevatorminus);
master.bind('', hover);
master.bind('p', stopall);
master.bind('l', liftoff);
 
mainloop()

import Tkinter as tk
import serial
 
# y = height
# x = turn
trim = 127
thrust = 0
direction = 127
elevator = 127
 
def writetoserial(*ignore):
        global thrust;
        global direction;
        global elevator;
        global trim;
        if thrust == -1:
            thrust = 0;
	ser.write(str(thrust) + ' ' + str(direction) + ' ' + str(elevator) + ' ' + str(trim) + ' :')
def printvar(*ignore):
	global thrust;
	global direction;
	global elevator;
	global trim;
	print 'Thrust = ' + str(thrust) + ' | Direction = ' + str(direction) + ' | Elevator = ' + str(elevator) + ' | Trim = '  + str(trim);
 
def showxy(event):
    global thrust;
    global direction;
    global elevator;
    global trim;
    xm, ym = event.x, event.y
    # show cordinates in title
    direction = xm / 3 ;
    thrust = ym / 3;
    writetoserial()
    printvar()
 
ser = serial.Serial('/dev/tty.usbmodemfa141', 9600);
root = tk.Tk()
frame = tk.Frame(root, bg= 'yellow', width=765, height=765)
frame.bind("", showxy)
frame.pack()
 
root.mainloop()

I’ve been compiling OpenCV today for some face tracking software builds and ran into a few problems getting it to compile.

Required:

• XCode installed
• MacPorts installed

sudo port install cmake

Two items from the Christmas goodies I’m looking forward to :

a) BigTrak Jr – it’s a small tank from the 80s that you can use a keypad on its back to program movements and tank fire. It comes with a 3.5 audio jack that is used for accessories that trigger 5v when the tank is fired. I’m thinking an arduino powered accessory for the top, or carefully putting a micro in the device in parallel so it can run off normal controller or be swapped to remote control via a cheap radio link.

b) a mini cooper rc car – this is just begging to have the controller messed with. It’s a nice simple job of some transistors to act as relays and boxing it back up again.

Just wish I had gotten myself a new soldering iron.

While Habari (http://www.habariproject.org) is a quiet well rounded piece of blogging software, and I’ve finally managed to get my head around blog theme templates, it is simply missing extra functionality that still only exists in WordPress.

Now, to get an idea of the installation.

Server: Ubuntu 11.10
Host: Linode

After backing up all of the required data, I deleted the last Ubuntu virtual disk and started again from scratch.

Apart from the standard server installation, the following commands were run:

apt-get update
aptitude safe-upgrade
tasksel
*Select LAMP Server*


After the installation of Apache, MySQL and PHP has completed, Virtual Servers need to be created. Both dddanmar.net and fffreak.net are hosted from the same platform:

rm /etc/apache2/sites-available/00-default
vi /etc/apache2/sites-available/00-VHOSTS
DocumentRoot /var/www/dddanmar.net
ServerName dddanmar.net
ServerAlias *.dddanmar.net
DocumentRoot /var/www/fffreak.net
ServerName fffreak.net
ServerAlias *.fffreak.net

Once that’s done, enable the new site

a2ensite 00-VHOSTS
service apache2 reload


Now, Apache will warn that the two /var/www folders do not exist. Installing WordPress and creating some symlinks solves this problem:

apt-get install wordpress
sudo ln -s /usr/share/wordpress /var/www/dddanmar.net
sudo ln -s /usr/share/wordpress /var/www/fffreak.net

Now, if you visit either domain WordPress complains about a lack of configuration files. Let’s start the WordPress configure script that comes from Ubuntu’s APT repos:

sudo bash /usr/share/doc/wordpress/examples/setup-mysql -n fffreaknet fffreak.net
sudo bash /usr/share/doc/wordpress/examples/setup-mysql -n dddanmarnet dddanmar.net

Now, the sites are available. Make the next step quickly or someone else may configure your blog! If you have done this for multiple VHOSTS, make sure you visit the other blogs and set them up to.

The WordPress demo site loads, so lets get some themes. I quickly jumped on to http://wordpress.org/extend and found some new themes:

wget http://wordpress.org/extend/themes/download/simpleblocks.1.0.1.zip
unzip simpleblocks.1.0.1.zip
wget http://wordpress.org/extend/themes/download/cammino.2.0.0.zip
unzip cammino.2.0.0.zip

Activate the themes for each site and presto, done!