Saturday, February 7, 2015

The Mozilla Manifesto



The Mozilla Manifesto are the principles that guide Mozilla's mission to promote openness, innovation & opportunity on the Web.


  1. The Internet is an integral part of modern life—a key component in education, communication, collaboration, business, entertainment and society as a whole.
  2. The Internet is a global public resource that must remain open and accessible.
  3. The Internet must enrich the lives of individual human beings.
  4. Individuals’ security and privacy on the Internet are fundamental and must not be treated as optional.
  5. Individuals must have the ability to shape the Internet and their own experiences on the Internet.
  6. The effectiveness of the Internet as a public resource depends upon interoperability (protocols, data formats, content), innovation and decentralized participation worldwide.
  7. Free and open source software promotes the development of the Internet as a public resource.
  8. Transparent community-based processes promote participation, accountability and trust.
  9. Commercial involvement in the development of the Internet brings many benefits; a balance between commercial profit and public benefit is critical.
  10. Magnifying the public benefit aspects of the Internet is an important goal, worthy of time, attention and commitment.






Tuesday, January 27, 2015

Dilbert RSS


Dilbert.com used to have an RSS feed, but has since removed this feature. Luckily, dilbert-rss was created by fredley, which allows anyone to create their own Dilbert RSS feed.

"dilbert-rssScrapes dilbert.com and generates an RSS feed.

Since dilbert.com nerfed their own RSS feed, I created a tool to replicate the old functionality. This is designed to be used on your own server, using cron to update it.
"

Usage

To use the dilbert-rss (assuming you want to store the RSS feed in /www/):
git clone https://github.com/fredley/dilbert-rss.git
cd dilbert-rss
python dilbert.py /www/dilbert.xml

Dependencies

Before you can use dilbert-rss, you will need to install two Python dependencies: BeautifulSoup and PyRSS2Gen
pip install BeautifulSoup PyRSS2Gen

BeautifulSoup and PyRss2Gen

On this topic, learning about the BeautifulSoup and PyRSS2Gen Python libraries were a benefit of using the dilbert-rss project. Both libraries can be used for a number of other useful projects. BeautifulSoup will parse an HTML page turning it into a usable Python object and PyRSS2Gen can be used to easily generate RSS feeds.

Oeey.com Dilbert Feed

An example of the output can be found here: http://dilbert.oeey.com/

Open the URL within an RSS viewer. If you don't have one handy, use Firefox to see the feed as a "Live Bookmarks" view. The content will be rendered. Most other browsers will just show the XML content.

With the above I created the following cronjob:
0 18 * * *   python /usr/local/bin/dilbert.py /www/dilbert/dilbert.xml
And the matching Apache configuration, with a default DirectoryIndex pointing to the XML feed:
<virtualhost>
    ServerName dilbert.oeey.com
    DirectoryIndex dilbert.xml
    DocumentRoot /www/dilbert
    ErrorLog logs/dilbert-error_log
    CustomLog logs/dilbert-access_log common
</virtualhost>



Update: Recently the Dilbert HTML layout changed. I had forked dilbert-rss and posted a suggested fix, to which fredley accepted the pull request.





Wednesday, January 21, 2015

Agile Manifesto



Individuals and interactions over processes and tools
Working software over comprehensive documentation
Customer collaboration over contract negotiation
Responding to change over following a plan


That is, while there is value in the items on
the right, we value the items on the left more.






Friday, January 2, 2015

Hacking Kankun Smart Wifi Plug

Kankun Smart Wifi Plug


The Kankun "Small K" (KK-SP3) Smart Wifi Plug Socket is an inexpensive device (~$20) that lets you switch an outlet on and off over Wi-Fi.

Smart Plug is a Controllable OpenWRT Linux BusyBox

Designed to be controlled by a smart phone, some engineering minds posted on Hackaday a way to control the device from any web browser or SSH client.  It turns out the Smart Plug is running a version of OpenWRT, which is basically a minimal BusyBox Linux environment (BusyBox: The Swiss Army Knife of Embedded Linux). It also has SSH access turned on by default, and was just a matter of determining the default password (admin, 1234, or p9z34c). Once you have SSH access you can either control the relay directly, or add a CGI script to control from a web browser.

root@koven:~# cat /etc/openwrt_release
DISTRIB_ID="OpenWrt"
DISTRIB_RELEASE="Bleeding Edge"
DISTRIB_REVISION="r39365"
DISTRIB_CODENAME="barrier_breaker"
DISTRIB_TARGET="ar71xx/generic"
DISTRIB_DESCRIPTION="OpenWrt Barrier Breaker r39365"

AliExpress

The Kunkun Smart Plug can be picked up on AliExpress for about $20.
"AliExpress is like eBay worldwide, but a lot bigger." (src)
Smart Plug package

There are a lot of options for purchase, just make sure you pick the US connector version (example), or you will need to buy an adapter (a mistake I made with the first one I ordered).

Smart Plug - US Connector Version

If you do get the wrong one, the front "female" receptacle connector was a universal connector, but the back "male" plug connector is the problem and you have to buy an adapter, so your device will end up looking like this:
Smart Plug - Chinese Connectors with US adapter
I should mention that one plug took 2 weeks to arrive and another took just shy of a full month. Different sellers, but both coming from China.

Factory Reset

As we make changes to the wireless settings, we can recover to the original factory settings by pressing and holding an almost-invisible white button on the surface of the plug for 4 seconds.

Configuring to SmartPlug Wireless Network

To get access and control to the Smart Plug, we first need to configure it.

Out of the box the Smart Plug is set as a Wireless Access Point, with an SSID of OK_SP3 (no password). To be useful, we will need to connect to this temporary access point and configure the device to connect to our home wireless network.



To configure the wireless, we can either:

1. Connect to the SSH service (default ip: 192.168.10.253) and modify the wireless files manually

or

2. We can use the Smart Phone Android/iOS app to configure the Smart Plug

I think the initial setup is easier with the app, so...

Configuring to SmartPlug Wireless Network - Android App Method


1. Download and install the Android Kankun "SmartPlug" app. (I assume the app on iOS is the same, but I haven't verified this)



For reference, I installed the app from the Google Play Store, but the instructions also provide a URL to download the app file: http://kk.huafeng.com:8081/android/Smartwifi.apk

2. Connect your Android Smart phone to the OK_SP3 network.

3. Start the SmartPlug app and click the "Config" button. Note: the "Device" page will be empty, unless you have already configured devices.



4. This is where we will change the Smart Plug's wireless network settings to our home network. Change the "Wifi" item to your home SSID (sorry no discovery option here). Change the Password to your home's wireless password. Ignore the "Encryption" option. Finally click the Configuring button to save the changes.



5. The Smart Plug should now be on your home's wireless network, and your Smart Phone will have been auto disconnected from the OK_SP3 network and also back on your home network. Check the status of the blue LED on the Smart Plug. If the LED is off, everything is good. If the light is blinking, it was unable to connect to your home wireless network.



6. Now check the "Device" list. Your Smart Plug should now be in the device list. Select the device.



Note: The device's Ethernet address (MAC) is also listed. Take note of the MAC, as you will want to check your DHCP server's logs to determine the IP address of your Smart Plug.

7. From here, we can quickly test the Smart Plug. We will be presented with a visual "on/off" button. Click the "on/off" a few times until you are satisfied. You will hear the relay switch on and off, or if you have something plugged into the Smart Plug, you will see it turn on and off.



7. Check your home's DHCP logs to find out what the new IP address of your Smart Plug is. Next we will connect to the Smart Plug over SSH.

Example:
dnsmasq-dhcp: DHCPDISCOVER(eth0) 00:15:61:bc:42:af
dnsmasq-dhcp: DHCPOFFER(eth0) 10.10.10.222 00:15:61:bc:42:af
dnsmasq-dhcp: DHCPREQUEST(eth0) 10.10.10.222 00:15:61:bc:42:af
dnsmasq-dhcp: DHCPACK(eth0) 10.10.10.222 00:15:61:bc:42:af


Configuring to SmartPlug Wireless Network - SSH Method


default /etc/config/wireless:
...

config wifi-iface
        option device radio0
        option network lan
        option mode ap
        option ssid OK_SP3
        option encryption none

change /etc/config/wireless:
...

config wifi-iface
        option device radio0
        option network wwan
        option ssid 'YOURSSID'
        option mode sta
        option encryption psk
        option key 'YOUR_WPA_KEY'

append /etc/config/network: (thanks Michael Liddle)
  config interface 'wwan'
  option proto 'dhcp'

After saving this file, reboot the Smart Plug and it should be connected to your home network. If the connection fails, perform the "factory reset" procedures to reset the network settings.
# reboot


SSH Password

Using your favorite SSH client, connect to the Smart Plug's IP address. Use "root" for the username, and "p9z34c" as the password (older models may have used "admin" or "1234").

$ ssh root@10.10.10.222
root@10.10.10.222's password:

BusyBox v1.19.4 (2014-03-27 17:39:06 CST) built-in shell (ash)
Enter 'help' for a list of built-in commands.

  _    _               _    _
 | | _-_| _____ _____  | | _-_| _____ ____
 |  -_-  |     ||     ||  -_-  |     ||    |
 | |-_   |  -  ||  |  || |-_   |  -__||   _|
 |  _ -_ |_____||__|__||  _ -_ |_____||__|
 |_| -__|  S M A L L   |_| -__| S M A R T
 -----------------------------------------------------
 KONKE Technology Co., Ltd. All rights reserved.
 -----------------------------------------------------
  * www.konke.com            All other products and
  * QQ:27412237              company names mentioned
  * 400-871-3766             may be the trademarks of
  * fae@konke.com            their respective owners.
 -----------------------------------------------------
root@koven:~#

You can then change the default password with the 'passwd' command.

# cat /etc/shadow | grep root
root:$1$4a45vajh$LVbmwoCs84PwyB.r2UdIN1:16185:0:99999:7:::

# passwd
Changing password for root
New password:
Retype password:
Password for root changed by root

Control Relay

Turning on and off the relay is really easy:

# turn relay on
echo 1 > /sys/class/leds/tp-link:blue:relay/brightness

# turn relay off
echo 0 > /sys/class/leds/tp-link:blue:relay/brightness


Web Interface

cnxsoft posted a simple CGI script (relay.cgi) to control the relay from a web interface:

Simply create the directory /www/cgi-bin/ and create the relay.cgi script as follows and give execute permission (chmod +x /www/cgi-bin/relay.cgi).

#!/bin/sh
echo "Content-Type: text/plain"
echo "Cache-Control: no-cache, must-revalidate"
echo "Expires: Sat, 26 Jul 1997 05:00:00 GMT"
echo

RELAY_CTRL=/sys/class/leds/tp-link:blue:relay/brightness

case "$QUERY_STRING" in
 state) 
  case "`cat $RELAY_CTRL`" in
   0) echo "OFF"
   ;;
   1) echo "ON"
   ;;
  esac
 ;;
 on) 
  echo 1 > $RELAY_CTRL
  echo OK
 ;;
 off) 
  echo 0 > $RELAY_CTRL
  echo OK
 ;;
esac

Open a browser and use the following URLs to control the relay:

http://your_device_ip/cgi-bin/relay.cgi?on

http://your_device_ip/cgi-bin/relay.cgi?off

Power Limits

The Smart Plug has a max current of 10 A or 2,200 W. A fire may be caused by exceeding these limits.



Google+ Group

Hacking the the Smart Plug now has a community group setup on Google+ Groups.










Friday, December 26, 2014

USB Connectors


Found this wonderful reference chart of the various popular USB connectors.  The male "plug" adapter inserts into the female "jack/receptacle".













Saturday, November 29, 2014

Big Ben Clock - Raspberry Pi


We mounted a large clock on the wall of our vaulted ceiling and wanted to give it a little more pizzazz. I wanted to give it a Big Ben feel, so I added some speakers, a Raspberry Pi, a little code, and voilĂ ! We now have a mini Big Ben of our own.

With a Wifi connector I am also able to remotely push other audio sounds to the speakers. Think speaker front end for a makeshift security system, or other audio states of your home automation. The possibilities are endless.


Demonstration




Code

The following is the code I wrote for the cronjob schedule and bash script to determine which audio file to play.

cronjob schedule:
# hourly from 7am to 10pm
0 7-22 * * *  /opt/big_ben/big_ben.sh > /dev/null

big_ben.sh:
#!/bin/bash

# Author: Kenneth Burgener  2014
# Purpose: Determine hour and play appropriate Big Ben MP3

# crontab: (from 7am and 10pm)
# 0 7-22 * * *  /opt/big_ben/big_ben.sh > /dev/null

# Get hour (1-12) for mp3 file
HOUR=`date +%l`
HOUR=$(( $HOUR ))

# Get military hour (1-24) for math below
MILHOUR=`date +%k`
MILHOUR=$(( $MILHOUR ))

# Set audio volume depending on time of day
if [ $MILHOUR -le 8 -o $MILHOUR -ge 20 ] ; then
    # 8am and earlier, 8pm and later
    #/usr/bin/amixer set PCM 80% > /dev/null
    /usr/bin/amixer set PCM 90% > /dev/null
else
    # 9am to 7pm
    #/usr/bin/amixer set PCM 95% > /dev/null
    /usr/bin/amixer set PCM 91% > /dev/null
fi

/usr/bin/mpg123 /opt/big_ben/audio/big_ben_$HOUR.mp3 2> /dev/null


Big Ben Audio

I found a good quality mp3 file that had the full 12 chimes. I then used Audacity to chop the file into smaller versions for the appropriate hour chimes.
  • big_ben.zip
    • big_ben_1.mp3
    • big_ben_2.mp3
    • big_ben_3.mp3
    • big_ben_4.mp3
    • big_ben_5.mp3
    • big_ben_6.mp3
    • big_ben_7.mp3
    • big_ben_8.mp3
    • big_ben_9.mp3
    • big_ben_10.mp3
    • big_ben_11.mp3
    • big_ben_12.mp3
  • big_ben_12.mp3






Sunday, November 9, 2014

Twitter Logger with Python


Want a more modern method for simple logging and notifications? Twitter is very popular, but it normally too "noisy" for me to follow for social messages. Add a bit of tech and now I have a reason to check Twitter at least once a day, or follow the events on my phone.

I had read articles in both Linux Journal and The MagPi Magazine about engineering minds using Twitter to receive notifications when certain events occur. I decided to take this a step further and create a tiny Twitter logger script for all of my Raspberry Pis. I now receive notifications for all kinds of events, such as:

  • Daily "alive" notifications
  • Reboots, power cycles
  • Changes in dynamic IP address
  • GPIO event triggers (think security alarm, garage door, sprinkler system, etc)
  • And anything else that fancies me at the moment

Code

How complicated is the Python? Easy. Only 3 lines (ignoring the line wrapping and commented debug code):
import twitter

api = twitter.Api(consumer_key='XXX',
                  consumer_secret='XXX',
                  access_token_key='XXX',
                  access_token_secret='XXX')

status = api.PostUpdate('This is my status update')

# print status.text

To use this code you will need to first generate your Twitter App API Access Keys and also install the python-twitter Python package.

Twitter App API Access Keys

Step 1 - Twitter Account: So how does one get started?  Well first, you need a Twitter account.  I assume you already have one, or at least don't need help creating one.

Step 2 - Mobile Phone: Unfortunately, your code will only be able to read status updates, unless you tie a mobile phone number to your account. Once you have validated your mobile phone, you will then be able to write/post status updates as well. Go to your account Settings and select the Mobile section. Add your mobile phone number, and wait for the validation code to appear on your phone. (note: I did attempt to try a couple of free burner mobile phone numbers, none of which ever received the validation code)

"You must add your mobile phone to your Twitter profile before granting your application write capabilities. Please read https://support.twitter.com/articles/110250-adding-your-mobile-number-to-your-account-via-web for more information"
Step 3 - Twitter App: Next, we need to create a Twitter App. This is nothing more than a method to get access to your api keys. Browse to https://apps.twitter.com/ and click the "Create New App" button.

Fill in the Name, Description and Website fields, then accept the agreement and continue.

The important field is the Name field as it has to be unique among all Twitter Apps. I just used my twitter account name, as I assumed no one else would be using that for an app name.

The Website field has to be populated, but won't be used. Put some temporary website and continue.

The Callback URL can be ignored.


Step 4 - Access Level: After the Twitter App has been created, find the Application Settings section and modify the Access level option by clicking the Modify App Permission link.  Change the access level from Read Only to Read and Write.  If you receive a warning about your mobile phone number, go back to step 2.

Step 5 - Access Keys: Finally, find the Application Settings section again and click the Manage Keys and Access Tokens link. You will find the consumer keys at the top of the page. Under the Your Access Token section, click the Create My Access Token button to generate the access tokens. If it isn't obvious the keys match the code variables as such:
consumer_key = "Consumer Key (API Key)"
consumer_secret = "Consumer Secret (API Secret)"
access_token_key = "Access Token"
access_token_secret = "Access Token Secret"

Now with your access keys, you can begin using the code above to update your twitter status with various notifications.

python-twitter

The python-twitter package "provides a pure Python interface for the Twitter API." To install the python-twitter package, simply use pip.
$ sudo pip install python-twitter

That was easy.

Check Status Code

The previous code showed how we can post a new update, but what about getting our current status, or someone else's?
import twitter
api = twitter.Api(...)

# get my timeline
statuses = api.GetUserTimeline()

# get a specific user's timeline:
# statuses = api.GetUserTimeline(screen_name=SCREEN_NAME)

# show latest message only:
print statuses[0].text

# show all returned messages:
for s in statuses:
       print s.text

Catch Errors

There are a few important errors that you will probably run across, and should handle:

Authentication failure: (check your keys, especially for accientally copied space characters)
twitter.error.TwitterError: [{u'message': u'Could not authenticate you', u'code': 32}]

Too long of a message: (shorten your message)
twitter.error.TwitterError: [{u'message': u'Status is over 140 characters.', u'code': 186}]

Duplicate message: (don't repeat messages or add a unique id, like time)
twitter.error.TwitterError: [{u'message': u'Status is a duplicate.', u'code': 187}]

User does not exist: (check the user name you are trying to query)
twitter.error.TwitterError: [{u'message': u'Sorry, that page does not exist', u'code': 34}]
test

Cronjob

I updated the twitter script to accept a message from the command line, and then added it to my cronjob:
@daily      /usr/bin/python /usr/local/bin/twitter alive
@reboot     /usr/bin/python /usr/local/bin/twitter reboot

Tips

#1 To be able to group and sort messages, I would recommend using the power of the hashtag. Pick a unique identifier (maybe your username) and append a category like this:
system startup #oeey_garage_pi

#2 To avoid the "Status is a duplicate" you may also wish to append a unique ID to all messages. I like to use the current linux epoc time, like this:
system startup #oeey_garage_pi (1415571010)

The updated posting code would look like this:
import time
...
status = api.PostUpdate('{message} #{category} ({id})'.format(
        message=message,
        category=category,
        id=int(time.time())

Issues


InsecurePlatformWarning:
/usr/local/lib/python2.7/dist-packages/requests/packages/urllib3/util/ssl_.py:90: InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#insecureplatformwarning. InsecurePlatformWarning
Solution: either ignore the warning or upgrade to at least Python 2.7.9 (or change code to use pyOpenSSL).

Other Libraries

If Python is not your thing, there a number of other Twitter libraries for various other programming platforms.

That's All Folks


Good luck, and have a good time playing with Python and Twitter.