Hackido

Recent Update to Gedit Find in Files

noreply@blogger.com (vince) — Tue, 30 Jun 2009 03:18:00 +0000

I've updated the Find in Files plugin for Gedit again. It should be a tiny bit faster and also be able to search special characters. That means you can search for "<%= link_to" instead of just "%= link_to". (Characters are now properly escaped.) The conflict with the Find in Documents plugin should also work.

The original instructions for using the plugin were on my old site, but the gist is that you (may) need SnapOpen and need to enable the default File Browser plugin. Once you enable the File in Files plugin a 3rd tab will appear at the bottom of the screen. Typing in any search results there will display any matching files under your File Browser root with matching results. Basically a glorified grep -R

At some point I may get ambitious and add the ability to exclude log files, but for the moment I'd suggest only searching within a modest scope. i.e. searching within your Rails App folder? Ok! Searching within your Rails Root folder? Not such a great idea because of the potentially large log files and also all the plugins you may have. You can try it but you've been warned..

Again, I welcome any contributions or forks, so please have at it. Gedit plugins are written in Python or C and I don't program either particularly well.

Validating form_tag in ActiveRecord

noreply@blogger.com (vince) — Mon, 29 Jun 2009 19:45:00 +0000

Activerecord valiations are seriously cool. If you just want to validate something in your form it's as easy as specifying the validation in your model and letting Rails take care of the rest. But what if you want to validate a form_tag? Generally, we use form_tag when there's no model associated with our form. Without the model we can't use Activerecord validations! Well, it turns out there's an elegant solution to the problem thanks to the Tableless Activerecord gem.

Now normally I'm pretty hesitant about adding a gem dependency to my application. These things tend to break between major rails upgrades and if the plugin developer isn't beholden to thousands of users it could be a while before you see a fix. In the end, if you're desperate, you could end up maintaining code you hadn't intended to.

The Tableless Activerecord gem is pretty straight forward though. Even though it hasn't been updated in a year, it seems to work fine with Rails 2.3.2. Usage is also pretty simple. To validate a contact form without a user model, just create a file called something like contact_messenger.rb and populate with the fields in your contact form and the validates you want:


class ContactMessage < ActiveRecord::Base

  has_no_table

  column :name,    :string
  column :email,   :string
  column :phone_number, :string
  column :message, :string
  
  validates_presence_of :name, :email, :message

end

In the above example, our contact form has fields for name, email, phone number, and message, but we're only requiring name, email, message. All other validations will work here as well so, for example, if you want to require the phone number be of a particular length you can do that as well.

Full instructions for using the gem/plugin can be found on Kenneth Kalmer's website.

Quick Tip: Set up a Reverse SSH Tunnel

noreply@blogger.com (vince) — Tue, 09 Jun 2009 00:05:00 +0000

Often times I find myself using ssh to get to a server in order to get a file. The problem is that my local machine doesn't have its own publicly accessible IP address. So I end up ssh'ing into the remote server, creating the file I need (e.g. database backup) and then exiting only to run scp from my local machine afterwards. Plus, if after that I want to erase the file on the remote server I have to ssh in again and tidy up after myself. That's me running ssh x2 and scp x1 every time I want to accomplish what should be simple. There's got to be an easier way, right? You bet..

First thing you'll want to do is ssh into your server but this time we're going to pass a -R flag and a port number. That flag "Specifies that the given port on the remote (server) host is to be forwarded to the given host and port on the local side." Basically a reverse tunnel..

ssh -R 19999:localhost:22 youruser@yourserver.com

Once you're in, you can ssh back to localhost:

ssh localhost -p 19999

or copy a file down:

scp -P19999 YOUR_FILE youruser@localhost:/home/youruser/

And that is all there is to it! Credit due to HowTo Forge for pointing the way on this. They've got a bit more on the topic that you can read about here.

Quick Tip: Search Email in Thinking Sphinx

noreply@blogger.com (vince) — Sat, 06 Jun 2009 16:24:00 +0000

If you use Sphinx as your search backend you may have noticed that it won't search for an entire email address. It's a bit perplexing at first since everything else works so well. After banging my head on the issue for a few hours, I got some direct help from Pat Allan, the creator of Thinking Sphinx. The problem is with the "@" symbol which is a reserved character in Sphinx. To get around that we need to modify Sphinx's allowable character set.

Now for better or for worse, you don't actually need to define any sort of config file by default to use Thinking Sphinx.. it's smart enough to pick sensible defaults. But in this case we'll have to go ahead and create one.

Every Ruby on Rails project comes with a config folder where many files you may need to modify are stored. In this directory create a file called sphinx.yml. It's a YAML file so be careful about spacing here. It's as sensitive as your database.yml file so if you accidentally alter the spacing things may not work.

For our example, let's use the UTF-8 character set. So in that sphinx.yml file, paste this content:

development:
  port: 3312
  charset_table: "0..9, a..z, _, @, A..Z->a..z, U+410..U+42F->U+430..U+44F, U+430..U+44F"
test:
  port: 3313
  charset_table: "0..9, a..z, _, @, A..Z->a..z, U+410..U+42F->U+430..U+44F, U+430..U+44F"
production:
  port: 3312
  charset_table: "0..9, a..z, _, @, A..Z->a..z, U+410..U+42F->U+430..U+44F, U+430..U+44F"

There are a number of other options you can put in your configuration file of course, but the charset_table one is going to be the one that helps you search email. In order to see the effect, you'll need to rebuild your index. If you've got a recent version of the Thinking Sphinx plugin:

rake thinking_sphinx:rebuild

Otherwise, you'll need to stop, index, and then start:

rake thinking_sphinx:stop
rake thinking_sphinx:index
rake thinking_sphinx:start

After that searching for emails should work!

Quick Tip: Nginx and cap deploy:web:disable

noreply@blogger.com (vince) — Thu, 04 Jun 2009 03:31:00 +0000

If you've followed my instructions for installing Ruby on Rails in Ubuntu you may have felt ambitious and also gotten Capistrano working too. The only issue is that, by default, nginx doesn't work with Capistrano's web:disable task. In order to get that working, you'll need to get your system folder setup, add a snippet of code below your server block and then restart nginx.

1. First let's add that snipped of code to nginx. If you installed nginx via phusion, then your configuration file is in /opt/nginx/conf/nginx.conf. Use any editor to add these lines within the server{} block:

if (-f $document_root/system/maintenance.html) {
   rewrite ^(.*)$ /system/maintenance.html break;
    }

2. Now that this is done, give nginx a restart:

sudo /etc/init.d/nginx stop
sudo /etc/init.d/nginx start

You can now try disabling the application using the capistrano task:

cap deploy:web:disable

3. If you get an error, that says:

Net::SFTP::StatusException (Net::SFTP::StatusException open /var/www/my_app/shared/system/maintenance.html (2, "no such file"))

Then you'll need to create a system folder. So log into your remote server and make sure that the you have a system folder with the right permissions setup.

mkdir -p /var/www/my_app/shared/system

Try it again:

cap deploy:web:disable

If it worked this time then you're done! Just don't forget to enable the server again using:

cap deploy:web:enable

Otherwise, be sure to check out the error message (most like a permission issue).

Sum and index a related column in Thinking Sphinx

noreply@blogger.com (vince) — Thu, 04 Jun 2009 00:13:00 +0000

It's fairly straight forward to get indexing working using the excellent Thinking Sphinx plugin. But sometimes you may want to do something a little more complicated. For example, if you have a Model foo with a has_many relationship to model Bar and you want to search on Bar how do you set it up? Or, what if you want to find out how many Bars Foo has? Enough! Let's work on an example.

Let's start and try to index a User model. That user has many bank accounts each of which has a balance:

User 1
--> Account 1 ($5)
--> Account 2 ($100)
--> Account 3 ($3)

User 2
--> Account 4 ($5)
--> Account 5 ($75)

In our example, we want to search for users by the amount of cash they have in their accounts. To do that we need to configure sphinx to first tell it that a User has many Accounts with a bank balance:


class Brigade < ActiveRecord::Base
  has_many :accounts
  
  #sphinx index
  define index do
    has accounts(:bank_balance), :as => :bank_balance
    indexes "SUM(bank_balance)", :as => :total_bank_balance, :sortable => true
  end
end

With that done, you can now do a search for users with a bank balance of $5 and it will return the 2 users with that balance. But, you can also do a search for users with a total bank balance of $80 and it will return only user #2.

10 little features: Android Cupcake

noreply@blogger.com (vince) — Mon, 01 Jun 2009 00:27:00 +0000

We've been hearing about Cupcake for a while and so the feature set is probably no mystery. I got tired of waiting for T-mobile to push the update down and so after a few false starts I decided to update myself (instructions here. After playing around, I found a few things which I thought I'd share in case you hadn't gotten the update yet. Here are a few of the minor things you've got to look forward to when it does finally come over the air.

1. You can now mute threads in Gmail. This feature is even more handy when you're on the road than when in front of your desktop. Nothing worse than sitting in the middle of a thread you care nothing about when travelling. I wonder how Google Wave will handle this..

2. Most applications will auto-rotate now. Auto-rotating had been disabled initially (rumored at Apple's request) but it's now been enabled. Almost all the apps, from games to the browser take advantage of this. If you're an app developer be sure to see what your app looks like when in landscape mode...

3. There's a software keyboard with autocomplete options and you get the ability to enable haptic vibrate response. T-9 on Android is still not possible due to patent issues, but luckily they've found another way to get the job done. As you type a small toolbar appears with a number of guesses on what you're typing. It's pretty effective. In fact my typing speed on the software keyboard quickly matched how fast I peck using the HTC G1 hardware keyboard.

4. If you hard press the power button it will let you both silence and enable airplane mode on the phone. Not much more needs to be said about this. It's nice to have and allowed me to uninstall the ToggleAir application.

5. When you press the any button other than menu and your phone is locked, it will show the wallpaper background. This helps identify your phone even when locked. Especially useful if you work in an office with multiple Android phone owners..

6. When you are on the phone, instead of having the screen black out and the dialpad disappear, it now stays on but makes you double tap to access the dialpad. Since the G1 doesn't have a hardware proximity sensor like the iPhone, it has no way of knowing when you hold it up to your ear and when you take it down to push a button (Apple really thought of everything didn't they!). This new behavior tries to do as best as possible given the lack of sensor.

7. The Email IMAP client now really deletes email from the IMAP server. If you spent a lot of time on the G1 without using the Google account as your mail email provider, you probably noticed right away that you couldn't really delete emails. Thankfully, this is now fixed.

8. Camera improvements: Speed to launch the camera has improved as well as the speed of taking a picture. It's almost usable now.. just missing a flash. Hopefully future Android phones figure this out. Plus, you can now just hold down the camera button to launch it. No more going through the app menu and clicking the camera icon.. As covered elsewhere, there is also a camcorder now.

9. Live folders and widgets: We've got calendar widgets and a live folder that will launch various things like 'contacts with phone numbers'. It's a small thing but it does add to the usefulness of the phone.

10. There are now animations when moving between screens and lots of minor polishing has been done. You can unlock even more here if you install the "Spare Parts" application from the market.

Overall Cupcake is an excellent update. I'm really looking forward to Donut though. I especially want the ability to have the phone turn itself on if you have the alarm set. Google: think of how much energy you would save the world if you enabled this!

Android apps I'm playing with this week

noreply@blogger.com (vince) — Thu, 21 May 2009 05:35:00 +0000

I'm (somewhat) patiently awaiting the cupcake build for my Android phone. While browsing around the market, I came across a few apps to take for a spin and thought I'd write a short post about them. Without further delay, here are four apps I kind of liked.

1. Contact Owner: This is a simple application but incredibly useful. When you launch it you select some preliminary text, a contact's information, and finally some concluding text. It will then display that message on your phone when it's locked. Why is that useful? It's intended for the scenario where you lose your phone and a some kind soul recovers it. In my case it might say:

If found, please return to:
Vince Wadhwani: 202-555-1212
Reward if returned.

Pretty handy, eh? Sure beats the paper and tape I usually use.

2. Slicehost: This is an application from the guys at Slicehost to help manage your slices. I have a few slices there so I thought I'd download it and give it a whirl. The only downside so far is that you have to enable API access on your slice and then manually type the API key into the application.

Slicehost rarely does anything badly, so I imagine there's a good reason to require the key and not just do it by one-time email/password retrieval. I think the other limitation is that you'll only be able to manage one account at a time which may or may not be a big deal for you depending on how many client slices you manage.

3. Connect Four: Yeah, this last one is a softball. I feel it's like tic tac toe and there's no reason to ever lose a round against the computer. But for whatever reason (concentration is the easiest culprit to blame) it is challenging. Fun too.

4. Spare Parts: If you've got cupcake, this is a nice addition. It allows you to add some features missing from the default options including keyboard animations and haptic responses. Worth playing with!

All the above apps are free so unless you're hurting for space I'd say give them a try.

Update your rails stack from Intrepid to Jaunty

noreply@blogger.com (vince) — Tue, 05 May 2009 03:23:00 +0000

If you've got a Rails Stack built on top of Intrepid Ibex and you want to update it to Jaunty, I've got some good news in that it's pretty easy. Depending on what you have installed though you may need to do a little extra repairing. Here's a quick step by step detailing my experience.

The first thing you must do is make sure your system is up to date:

sudo apt-get update
sudo apt-get dist-upgrade

Install any packages that are out of date. After that, time to get the update manager:

sudo apt-get install update-manager-core

Since we're upgrading from Intrepid Ibex to Jaunty Jackalope there shouldn't be a reason to modify any other files like you might when upgraded from the LTS. So get straight to the matter by running this command:

sudo do-release-upgrade

Follow the on-screen instructions. If you're not an advanced user, I'll recommend just taking whatever defaults you are prompted with. Once you're done, reboot!

A couple of things went wrong with my upgrade. First, my Passenger Phusion install went awry. This was 100% my fault though for not upgrading the right way. Just in case you missed it, follow the instructions on the official blog.

The second thing I needed to fix was my rmagick install. A key library got removed and so it was back to the drawing board. Luckily, I found some easy instructions courtesy of Rob Britton.

sudo apt-get install libmagickwand-dev
sudo gem uninstall rmagick
sudo gem install rmagick --no-ri --no-rdoc

And with that you should be done, and hopefully enjoying your upgraded stack. It also couldn't hurt to do a sudo gem update just in case you have some old crud hanging around.

Quick Tip: Fix RSS feeds in Rails 2.3

noreply@blogger.com (vince) — Fri, 24 Apr 2009 18:04:00 +0000

I saw a sudden drop in the RSS subscribers on one of my site's feeds and it led me to investigate what happened. Turns out that RSS feeds changed every so slightly in Rails 2.3. Actually, it might even be a bug. The symptom is that when you visit your sites rss feed you are prompted to download the file instead of viewing it in an RSS program.

If you download the file and inspect it, you'll likely see a bunch of stuff that doesn't belong in an RSS feed at all. Even more confounding is that emptying out your index.rss.builder file still makes your browser download a file. The culprit is that Rails 2.3 shows the layout file for RSS feeds just like it would for a respond_to html. To fix it add a render_layout => false to your controller like so:

 def index
    @articles = Article.find(:all, :limit => 8, :order => 'created_at desc')
    respond_to do |format|
      format.html
      format.rss { render :layout => false}
      format.xml  { render :xml => @articles.to_xml }
    end
  end

Tada!

Install Ruby Rails on Ubuntu 9.04 Jaunty Jackalope

noreply@blogger.com (vince) — Mon, 20 Apr 2009 12:56:00 +0000

It's getting easier to install Ruby on Rails all the time. I thought about skipping actually writing this tutorial until I heard that Phusion Passenger 2.2.0 supported Nginx. I was pretty psyched and so ran off to do an install with that new stack. If you want a head start on it or need a step by step tutorial then by all means click through for instructions.

Step 1: As usual, the first thing we'll want to do is make sure your version of Ubuntu is up to date.:

sudo apt-get update
sudo apt-get dist-upgrade

Step 2: We'll be installing some software that needs to be built so we'll need to get packages required for compiling. Luckily, you can type this single command and get everything you need:

sudo apt-get install build-essential

Step 3: Once you've got the tools, it's time to install MySQL and Ruby. If you're using SQLite you may not need all this stuff. Otherwise, just copy and paste this command into your terminal if you're in a hurry.

sudo apt-get install ruby ri rdoc mysql-server libmysql-ruby ruby1.8-dev irb1.8 libdbd-mysql-perl libdbi-perl libmysql-ruby1.8 libmysqlclient15off libnet-daemon-perl libplrpc-perl libreadline-ruby1.8 libruby1.8 mysql-client-5.0 mysql-common mysql-server-5.0 rdoc1.8 ri1.8 ruby1.8 irb libopenssl-ruby libopenssl-ruby1.8 libhtml-template-perl mysql-server-core-5.0

If you hadn't previously installed MySQL you'll be asked to set a root password. You don't have to, of course (it will bug you no fewer than 3 times if you opt not to) but I strongly recommend it. You'll need this password when you populate your rails config/database.yml file so be sure not to forget it.

Step 4: Grab the latest ruby gems and install them. As always be sure to check rubyforge.org to make sure you're grabbing the latest one. As of this writing it's 1.3.4 but it never hurts to confirm.

wget http://rubyforge.org/frs/download.php/57643/rubygems-1.3.4.tgz
tar xvzf rubygems-1.3.4.tgz
cd rubygems-1.3.4
sudo ruby setup.rb

Once it's done you can remove the .tgz file and erase the rubygems-1.3.4 directory too.

Step 5: On the command line, type gem -v. if you get this message we need to make some symlinks:

The program 'gem' can be found in the following packages:
 * rubygems1.8
 * rubygems1.9
Try: sudo apt-get install 
-bash: gem: command not found

Let's create those symlinks now:

sudo ln -s /usr/bin/gem1.8 /usr/local/bin/gem
sudo ln -s /usr/bin/ruby1.8 /usr/local/bin/ruby
sudo ln -s /usr/bin/rdoc1.8 /usr/local/bin/rdoc
sudo ln -s /usr/bin/ri1.8 /usr/local/bin/ri
sudo ln -s /usr/bin/irb1.8 /usr/local/bin/irb

Step 6: Install Ruby on Rails! You can leave off the --no-rdoc and --no-ri switches if you're on a machine with plenty of ram. But just in case you've got a more modest setup (say 256MB or less) I'd just use the following:

sudo gem install rails --no-rdoc --no-ri

If you're just doing local development then you are basically done. You may want to install additional gems (such as mongrel). If you want to deploy Ruby on Rails onto a server then it's time to setup Nginx and Phusion.

Step 7: The folks responsible for Phusion (Hongli Lai & Ninh Bui) have done a remarkable job. They truly understand what it means to make using your product easy for customers. It's one reason we love Phusion. Nginx doesn't support loadable modules like Apache does, so Phusion will download, compile, and install it for you. What could be easier? To get started, let's download the packages we'll need:

sudo apt-get install libc6 libpcre3 libpcre3-dev libpcrecpp0 libssl0.9.8 libssl-dev zlib1g zlib1g-dev lsb-base

Step 8: We're going to create a directory for your application. In anticipation of Capistrano, let's put it in /var/www/myapp/current. Swap out the myapp with anything you like.

sudo mkdir -p /var/www/myapp/current

If you've got an existing Rails application, it doesn't hurt to populate that directory now. Just make sure that the root to the public directory is /var/www/myapp/current/public. Don't forget to chown it for www-data:

sudo chown -R www-data:www-data /var/www/myapp/current/

Step 9: Now it's time to install Phusion Passenger and let it do it's magic. It's critical that you have Phusion Passenger 2.2.1 or greater installed. This may not work with 2.2.0.

sudo gem install passenger
sudo passenger-install-nginx-module

At this point you'll be greeted with two options. The first will allow Passenger to do all the work while the second, for advanced users, allows you to point Phusion to your pre-installed Nginx. We're going to make life easy on ourselves and choose option 1. I'd also recommend keeping the default path (/opt/nginx).

The Nginx configuration file (nginx.conf) file is in /opt/nginx/conf/ They've done you the favor of adding the lines you need to get going. Defining the configuration file is beyond the scope of this tutorial, but I've included a sample file which you can download. This file assumes your application is in /var/www/myapp/current.

Sample nginx.conf file for Ruby on Rails, Nginx, Phusion Passenger.

Step 10: Time to make some Nginx tweaks for Ubuntu/Debian. If you're used to running nginx as installed by Debian or Ubuntu then you might notice that you've lost the familiar way to start and stop nginx. Gone is /etc/init.d/nginx stop and /etc/init.d/nginx/start. To get it back, copy (or download) this into a file called nginx in /etc/init.d/ (as root)

#! /bin/sh

### BEGIN INIT INFO
# Provides:          nginx
# Required-Start:    $all
# Required-Stop:     $all
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: starts the nginx web server
# Description:       starts nginx using start-stop-daemon
### END INIT INFO

PATH=/opt/nginx/sbin:/sbin:/bin:/usr/sbin:/usr/bin
DAEMON=/opt/nginx/sbin/nginx
NAME=nginx
DESC=nginx

test -x $DAEMON || exit 0

# Include nginx defaults if available
if [ -f /etc/default/nginx ] ; then
        . /etc/default/nginx
fi

set -e

case "$1" in
  start)
        echo -n "Starting $DESC: "
        start-stop-daemon --start --quiet --pidfile /opt/nginx/logs/$NAME.pid \
                --exec $DAEMON -- $DAEMON_OPTS
        echo "$NAME."
        ;;
  stop)
        echo -n "Stopping $DESC: "
        start-stop-daemon --stop --quiet --pidfile /opt/nginx/logs/$NAME.pid \
                --exec $DAEMON
        echo "$NAME."
        ;;
  restart|force-reload)
        echo -n "Restarting $DESC: "
        start-stop-daemon --stop --quiet --pidfile \
                /opt/nginx/logs/$NAME.pid --exec $DAEMON
        sleep 1
        start-stop-daemon --start --quiet --pidfile \
                /opt/nginx/logs/$NAME.pid --exec $DAEMON -- $DAEMON_OPTS
        echo "$NAME."
        ;;
  reload)
          echo -n "Reloading $DESC configuration: "
          start-stop-daemon --stop --signal HUP --quiet --pidfile     /opt/nginx/logs/$NAME.pid \
              --exec $DAEMON 
          echo "$NAME."
          ;;
      *)
            N=/etc/init.d/$NAME
            echo "Usage: $N {start|stop|restart|reload|force-reload}" >&2
            exit 1   
            ;;
    esac

    exit 0

Next, let's set the permissions and make nginx load on a reboot:

sudo chmod +x /etc/init.d/nginx
sudo /usr/sbin/update-rc.d -f nginx defaults

Now you should be able to start and stop nginx using the command you're used to:

sudo /etc/init.d/nginx start

Bonus step In case it's not already installed, let's grab the perquisites and then install the mysql gem. This will improve performance on your webserver:

sudo apt-get install libmysqlclient-dev
sudo gem install mysql --no-rdoc --no-ri

Troubleshooting If things didn't go smoothly, here are some things to check:

1. There's an error log for nginx in /opt/nginx/logs/ Try looking to see if you get any hints there.

2. If you see a 403 forbidden error, make sure you have permissions set correctly. I'm running Nginx as www-data and I've set the group/user owners of my rails app to match using the chown -R www-data:www-data command. It doesn't hurt to confirm it.

3. Try running your rails app in development mode using the standard script/server. If it doesn't work there then it obviously won't work in production mode either

For help, you should check out the great railsforum or Mailing list front-end.

Swapping Control & Alt in Linux

noreply@blogger.com (vince) — Sun, 19 Apr 2009 05:32:00 +0000

More for my own reference and in preparation of me completely gutting my system, I'm posting the contents of my .xmodmaprc file which swaps the left control and alt-keys. This allows me to use my linux laptop more like I used my mac, with the command key.

Feel free to copy the contents to a file called .xmodmaprc and run it using the xmodmap command:

xmodmap .xmodmaprc

remove Control = Control_L
remove Mod1 = Alt_L
keysym Control_L = Alt_L
keysym Alt_L = Control_L
add Control = Control_L
add Mod1 = Alt_L

Named Scopes and Thinking Sphinx

noreply@blogger.com (vince) — Sat, 18 Apr 2009 22:18:00 +0000

I'm really not a fan of the Thinking Sphinx conditions syntax. It's different than what I'm used to using in ActiveRecord and has caused me some problems with dates and such. Instead I use named scopes whenever I can. For example, in Railfood, a site for locomotive parts, I use a named scope to show only products that are in stock. That causes some issues, not only because of all the nil records but because the default number of results returned is 20.

For example:

@p =Product.current.search("injector").size 

=> 20

@p =Product.current.search("123").size 

=> 20

One of the first gotchas (covered here too) is that if you actually inspect that array you'll see that it's filled with nil.

[nil, nil, nil, nil nil,nil, nil, nil, nil nil,nil, nil, nil, nil nil,nil, nil, nil, nil nil,]

To get around it, call the compact method on the array:

@p =Product.current.search("injector").compact.size 

=> 0

The other gotcha here is that if you actually have 20000 records that match "injector" but only 1 of them is current, you'll get zero results. To work around that you need to increase the maximum amount of results per page:

@p =Product.current.search("injector", :per_page => 20000).compact.size 

=> 1

But what about pagination? Thinking Sphinx does give us this, but the fact that both the methods are called :per_page kind of screws things up. To work around this, just call paginate on your results:

@p =Product.current.search("injector",
                   :per_page => 20000).paginate(:per_page => 8, :page => params[:page])

And that should do it. Of course, depending on how many results you have you may need to up the initial per_page from 20000 to something larger. This isn't ideal in my humble opinion, but it works for the moment. Other suggestions are welcome!

While we're on the subject of Thinking Sphinx, be sure to set :enable_star => 1 in your index block if you want to use wildcards in your searches.

Testing Attachment Fu in Rails Test Unit

noreply@blogger.com (vince) — Fri, 10 Apr 2009 02:19:00 +0000

Whether you're using standard Test Unit or Shoulda, you should be testing models. But if a User model has to have a Photo, how do you set up a unit test to make sure it passes? I've read blog posts and forums threads on the issue but never found anything comprehensive enough for a entry-level rails tester to understand. So, with that in mind, read on for a quick tutorial.

I'm using Shoulda so my tests are geared for that syntax. If you're using Test Unit, feel free to modify accordingly. The meat of the answer is still the same.

First of all, let's assume you're in the test/unit/user.rb file doing your unit test. Your file starts off looking like this:

require File.join(File.dirname(__FILE__),"..","test_helper")

class UserTest < ActiveSupport::TestCase
end

You'll want to add your context block, setup block, and an assertion too.


context "A new user with a valid photo" do
 setup do
   @user = User.create(:email => "test@example.com", :login => "test", :password => "password123", :password_confirmation => "password123")
 end

  should "be a valid user" do
     assert(@user.valid?)
   end
end

Running the above test won't work if you're requiring a photo because you haven't actually set one up. To do that you'll have to use create the photo in the test like this:


@photo = Photo.create(:uploaded_data => fixture_file_upload("/files/mugshot.png",'image/png')

The tricky part is that the fixture_file_upload is a part of ActionController::TestProcess. So you'll need to include it for it to work. The final user.rb will therefore look like this:

require File.join(File.dirname(__FILE__),"..","test_helper")

class UserTest < ActiveSupport::TestCase
  include ActionController::TestProcess
  context "A new user with a valid photo" do
    setup do
      @photo = Photo.create(:uploaded_data => fixture_file_upload("/files/mugshot.png",'image/png'))
      @user = User.create(:email => "test@example.com", :login => "test", :password => "password123", :password_confirmation => "password123", :photo => [@photo])
    end

    should "be a valid user" do
      assert(@user.valid?)
    end
  end
end

Now when you run your test, it should pass:

ruby test/unit/user.rb

Started
.
Finished in 0.196 seconds.

1 tests, 1 assertions, 0 failures, 0 errors

A few things to look out for:

- The above assumes a User has many Photos which is why it's photos => [@photo] and not photo => @photo.

- You'll need to create a file called mugshot.png and put it in the test/fixtures/files directory (which you probably need to create)

- I'm using Shoulda, if you use straight test::unit or rspec, you'll need to change things appropriately.

- My example also assumes the only things required in your user model is the email, login, password, and photo. Adjust accordingly.

Hopefully the above works for you. Now that you're validating attachments correctly there's no reason not to do more testing!

XFCE 4.6 makes it into Debian Experimental

noreply@blogger.com (vince) — Sun, 29 Mar 2009 18:17:00 +0000

After a long long wait, Debian Experimental is finally blessed with XFCE 4.6. To install it you have to enable the experimental repository. Put this line in your /etc/apt/sources.list file somewhere:

#Debian Experimental
deb http://ftp.debian.org/debian/ experimental main non-free contrib

Next run an update and upgrade:

sudo apt-get update
sudo apt-get dist-upgrade

Finally, grab the XFCE 4.6 packages:

sudo apt-get install xfce4 -t experimental

There are a number of improvements in XFCE 4.6 but the big winner for me is the multiple selection of icons on the Desktop. Something that other DE (including LXDE) have been doing forever.

Autocomplete associated fields in Rails 2.3

noreply@blogger.com (vince) — Sat, 28 Mar 2009 16:57:00 +0000

I recently had to use an autocomplete field and populate the associated form fields depending on the result. It's not that bad to do using javascript if you know what you're doing. The last part is the key of course. It took me a while to figure it out so I thought I'd share. So if you're using Ruby on Rails and want to pull it off, here's a step by step on how to do it.

First thing you need to do is install the autocomplete plugin for Rails as this functionality was removed from core quite a while ago:

ruby script/plugin install auto_complete

In this example we'll be working with a Charity model. We'll be grabbing the charity name using an autocomplete text box and filling in another field.

This assumes you have your form already set up correctly, so first get the text field with autocomplete set up:

<%= text_field_with_auto_complete :charity, :name %>

Next, let's observe that field:

<%= observe_field 'charity_name', :on => 'blur', :frequency => 0.50, :url => {:action => 'update_fields'}, :with => "'name=' + element.value"  %>

In our example we'll set up one more field which we'll have populated. Let's call it address:

<%= f.text_field :address %>

Remember that your field name may vary depending on how your form is setup. If unsure, use firebug or view the source of your form.

Lastly, let's get some controller code in the update_fields action. This is where we call our javascript.


  def update_fields
    @charity = Charity.find_by_name(params[:name])
    if @charity.nil?
      render :nothing => true
    else
      render :update do |page|
      page['charity_address'].value = @charity.address
    end
  end

In the above example you can fill in as many associated fields as you'd like. You can also put the above into an RJS.. frankly that might be better but I like to have logic in my models first, then my controllers, and lastly in any views.

undefined method `use_transactional_fixtures=' in Rails 2.3

noreply@blogger.com (vince) — Wed, 18 Mar 2009 15:46:00 +0000

I'm trying to be better about testing these days so when I upgraded to Ruby on Rails 2.3 the other day I was a bit dismayed to be getting errors with my tests. They went something like this:


undefined method `use_transactional_fixtures='

Ug. I generated a new Rails 2.3 app to find out what was going on.

Turns out the problem is in the test_helper.rb file. You'll need to swap out the old class definition with this:

class ActiveSupport::TestCase

Once you do that your tests should run again (assuming they did before hand).

Quick Tip: Solve uninitialized constant ApplicationController in Rails 2.3

noreply@blogger.com (vince) — Tue, 17 Mar 2009 01:02:00 +0000

If you've just upgraded your Rails stack to 2.3 you may be seeing a strange error:

uninitialized constant ApplicationController

Turns out, among the Major changes that came along with the latest Release of Ruby on Rails, there were a few minor ones too. One of those is that the application controller is no longer called application.rb Now it's referred to as application_controller.rb.

In effect, to solve this problem, just rename the file. Or, as Liam points out in the comments below, run:

rake rails:update

Be sure to update your server stack before deploying. Obviously if you rename the file to get it working on Rails 2.3 and upload to a Rails 2.2 server you'll be in trouble. Don't forget that Rails 2.3 also requires a new version of Phusion Passenger!

Useful font and tab tweaks for Iceweasel

noreply@blogger.com (vince) — Wed, 04 Mar 2009 16:47:00 +0000

I had to erase my .mozilla folder today.. ran into a weird problem with gmail. Whenever I start off with Firefox/Iceweasel for the first time there are always some font adjustments I need to make in the about:config section. These settings generally match what ships by default in Windows. On the Linux side though these can vary depending on the distro. If you happen to have some font-rendering issues, try these settings:

font.size.variable.x-western: 16
font.size.fixed.x-western: 13
font.minimum-size.x-western: 0

Ridiculous website policies

noreply@blogger.com (vince) — Sat, 28 Feb 2009 20:20:00 +0000

I've been changing passwords around lately, something that I like to do every once in a while to keep myself on my toes, and I have to say that I am still shocked to see some of the requirements in place by certain places. More than 1 financial institution has password limitations that actually weaken what you can do!

For example, here's the policy from American Express

# Contain 6 to 8 characters - at least one letter and one number (not case sensitive)
# Contain no spaces or special characters (e.g., &, >, *, $, @)
# Be different from your User ID and your last Password

Seriously? I'm limited to an alphanumeric password no larger than 8 characters and no smaller than 6? I understand that they have other limitations in place to prevent a computer from brute-forcing the password, but I can't help but think these requirements are unhelpful and unnecessary.

It's time for all webmasters who store passwords to make sure that these silly limitations are removed. Here are some policy recommendations:

Special characters and spaces should be allowed and even encouraged.
Minimum password length enforcement makes sense, but if you're going to have a maximum make sure it's at least 16 characters
All passwords should be encrypted and salted in your database
Require 5-10 seconds in between each failed login

Finally, provide your users with an password strength indicator so they know if they've selected something easy to break. Microsoft actually does a great job of this. Assuming you can find how to change your password in hotmail, they provide good feedback when you do it. They even have some recommendations of their own you should look at..

Quick Tip: Sort by directory size

noreply@blogger.com (vince) — Sat, 14 Feb 2009 19:56:00 +0000

If you've got files hidden around your system and you don't know where they are, you can use a quick command to track them down. Try this:


sudo du --max-depth=1 /home/ | sort -n -rs

The great exhale

noreply@blogger.com (vince) — Wed, 11 Feb 2009 05:55:00 +0000

I'm not sure if anyone else has noticed, but it seems like the Internet has gotten quieter recently. There's more activity on sites like Facebook and Twitter and many other established websites continue to grow and publish, but the smaller bloggers seem to be letting out a long, deep breath. I wonder if they're asking themselves whether it's worth it?

My blogging has slowed down a bit but mostly because my learning has slowed down. I continue to work of course, but mostly creating things with skills I already have. The economy dictates I focus my energies on cash generation and, let's face it, blogging doesn't bring in much cash for most of us.

I was just on polishlinux.org and noticed there hadn't been a post since December. OSNews also seems to have slowed down a bit compared to where it was when Eugenia was running it. What's going on blogosphere? You all spending your time on Digg & Reddit?

Top 10 Android App's II

noreply@blogger.com (vince) — Sun, 25 Jan 2009 20:11:00 +0000

I did a writeup on my Top Android Apps back in November. How times change! After 2 months of using my G1, a lot of the apps I wrote about have been erased and replaced with new ones. Here's the current state of the android. (With a few exceptions all these apps are available through the Market!)

10. Toggle WiFi: This is a solid little app that does one thing but does it well: it toggles the WiFi on and off. That's especially handy if you use a streaming audio application (#4). For example StreamFurious will cut out when you make the transition from 3G to WiFi or vice versa.

9. AK Notepad A super simple notebook application that lets you type in text freeform. It's a hold over from my last list. Simplicity works!

8. Video Player: One of the apps that dropped off my list from last time is DoggCatcher. I just am not listening to as many podcasts anymore. I'm also not watching many videos on my G1 these days, but it is a handy app for those occasions when you do need to watch something.

7. WeatherBug: Another hold over from my last Top 10. If you need to find the weather this is a good choice. Not as invasive as other weather apps though I've heard that these guys used to do nasty things on other platforms.. (I'm keeping an eye on you!)

6. Shazam: The ultimate music identifying application. Out somewhere and want to ID that song that's playing? This your solution!

5. Steel: An alternative to the native browser, this application has made really good progress. It seems just as fast and has a few extra features such as a built-in software keyboard and an auto-rotate of the screen depending on how you're holding it. Two features that the Android team may not have included due to patent concerns.

4. StreamFurious is an application that let's you stream audio from icecast servers. I use it to listen to NPR since the G1 lacks a radio. Very cool.

3. Tetherbot: Although it isn't a true tethering application, it will let you use your G1's connection to access the net on your laptop's web browser. Given how much you can do through a browser these days, it's a pretty awesome app.

2. aTrackDog: One of the constant headaches is keeping the already installed apps on your phone up to date. Enter aTrackDog which does it for you. Launch the app and it'll let you know how many of the applications on your phone have newer versions. It's almost like and apt-get update && apt-get dist-upgrade but for Android. Very handy until an official solution appears!

1. ConnectBot: I use this app all the time. It seems that anytime I need to access a server I'm without my laptop. This is the all time most useful app I'm run into on my Android phone and the single biggest reason the iPhone is a non-starter for me.

A rake task to generate a google sitemap

noreply@blogger.com (vince) — Thu, 22 Jan 2009 22:46:00 +0000

I wanted to generate a dynamic sitemap on the off-chance it would help with Google results. Static sitemaps are pretty straight forward but if you've got a lot of stuff and they change daily, then hand editing files just won't do it. In that case you need to use a rake task along with cron to regenerate a sitemap. Here's one way you can do that.

In this scenario, I'm assuming you have a bunch of stores and that you want the sitemap to list them all. (You should replace your find statement with whatever you feel is appropriate to your sitemap.)


desc "Generate a sitemap.xml file"
task :generate_sitemap => :environment do |t|
  filename = "#{RAILS_ROOT}/public/sitemap.xml"
  stores = Store.find(:all)

  File.open(filename, "w") do |file|
    xml = Builder::XmlMarkup.new(:target => file, :indent => 2)
    xml.instruct!
    xml.urlset "xmlns" => "http://www.sitemaps.org/schemas/sitemap/0.9" do
      for store in stores
        xml.url do
          xml.loc "http://www.buyindie.net/stores/#{store.id}-#{store.name.gsub(/[^a-z0-9]+/i, '-')}"
          xml.lastmod store.updated_at.xmlschema
          xml.changefreq "weekly"
          xml.priority 0.6
        end
      end
    end
  end       
end

Running that file will generate a sitemap.xml file which you can submit to The Google for inclusion. There are other ways to do this though. One criticism about using scripts like this is that if there's an error in the sitemap, it may not be obvious to other programmers where the code that generates the sitemap is.

To address that, one could generate the sitemap in the same way one would generate an RSS feed. Sprinkle in some page caching and expiration and you're on your way to having a sitemap generator that is friendly enough to share with your fellow coders.

Under the covers: BuyIndie

noreply@blogger.com (vince) — Thu, 15 Jan 2009 23:18:00 +0000

Although it's still not what I consider to be a finished website, BuyIndie had improved enough for me to go ahead and relaunch it. The previous version was pretty crusty and wasn't even close to a decent representation of what we could do. It had broken css, broken html, broken ruby code, and various outdated components. As an experiment, I thought it would be fun to list a few of the open source components we used to update the site this time around.

Out with Ferret in with Sphinx. Ferret had a ton of limitations but the most annoying was the inability for it to search for anything with special characters. Search for "Hank" and you got what you were looking for, but "Hank's" would yield nothing. Sphinx is way faster, it's more powerful, and there are several good plugins that you can use. We went with Thinking Sphinx For browsing, it's acts as attachment on steriods (also tailored).

GeoKit stays strong. When it comes to doing work with Google Maps, GeoKit is an excellent plugin. It was present in the last iteration of BuyIndie and remains in this one as well. Recently updated I believe so it's not dead by any means.

Some Technoweenie, please. Though both have been modified from their initial states, Attachment Fu and Restful Authentication make up the image and user handling parts of the site. They remain great plugins though I think in future projects I may go with some upcoming plugins such as Paperclip and Authlogic. Akismet, Redcloth and Open-ID also help with authenticating, formatting, and containing user input.

PDF Generation: If you send a list to somebody on BuyIndie, we generate a one page PDF so the recipient can easily print out the map/list and take it with them. We decided to go with Prawn for the PDF generation. Though it had some rough patches, it's now stabilized enough to make it worthwhile to use in production.

Ship It! The last time around I was on a private server.. this time I opted to go with Slicehost. So far so good there.

There's plenty of other gems mixed in, but hopefully the above gives you a small peek into what's going on under the covers!