Problem

I have a fairly standard

belongs_to

Sounds easy. That’s what I thought when I started.

My Solution

 Models

We have an Organization and a SubUnit models, pretty standard stuff here.

lass SubUnit < ActiveRecord::Base
  attr_accessible :name, :organization_id
  belongs_to :organization

  validates :name,
            presence: true,
            uniqueness: { scope: :organization_id }
end

class Organization < ActiveRecord::Base
  attr_accessible :name, :sub_units_attributes
  has_many :sub_units, dependent: :destroy
  accepts_nested_attributes_for :sub_units, allow_destroy: true, reject_if: proc { |a| a["name"].blank? }
  validates_presence_of :name
end

Controller

The controller is simple (standard actions removed). Keep scrolling down.

# controllers/organizations_controller.rb
class OrganizationsController < ApplicationController
  def new
    @organization = Organization.new
    @organization.sub_units.build
  end

  def create
    @organization = Organization.new(params[:organization])

    if @organization.save
      redirect_to @organization, notice: 'Organization was successfully created.'
    else
      render :new
    end
  end
end

View

Now it’s getting interesting.

# organizations/new.html.haml
= form_for @organization, :html => { :class => 'form-horizontal' } do |f|
  .row-fluid
    .span6
      .well
        %h2 Organization Info
        .control-group
          = f.label :name, :class => 'control-label'
          .controls
            = f.text_field :name, :class => 'text_field input-medium'

    .span6
      .well.sub-units
        %h2 SubUnit Info
        = f.fields_for :sub_units do |f_sub|
          = render 'sub_unit_fields', f: f_sub

        .control-group.add-sub-unit
          .controls
            = link_to 'add a SubUnit', '#', class: 'btn btn-primary add-sub-unit-button'

        #new-sub-unit-fields.hidden
          = f.fields_for :sub_units, SubUnit.new, child_index: 'new_sub_unit' do |f_sub|
            = render 'sub_unit_fields', f: f_sub

    .span12
      .form-actions
        = link_to 'Create Organization', '#', class: 'btn btn-primary create-organization-button'
        = link_to t('.cancel', :default => t("helpers.links.cancel")), organizations_path, :class => 'btn'

# _sub_unit_fields.html.haml
.control-group
  = f.label :name, class: 'control-label'
  .controls.sub-unit
    = f.text_field :name, class: 'input-mini'
    = f.hidden_field :_destroy
    = link_to "remove", '#', class: 'btn btn-warning btn-mini remove-sub-unit-button'

Your form should look like this.

Polluting Links with Javascript

Like everyone else who has started down the road to nested attribute bliss, you have watched Ryan Bates’ Railscast on Complex Forms. It’s superlative.

But there’s one thing I didn’t like… the heavy handed approach of using link_to_function. Especially when including a fair amount of escaped html into an onclick script. I’m not saying it’s wrong, just that I believe html should stay where it belongs… in the DOM. Heck, they even created a gem nested_form.

I think we can make it simpler, painless, elementary.

That’s where the following little ditty comes in handy. We are creating the exact same field structure that is used for entering a SubUnit, but hiding the html so that we can use JavaScript to copy-and-append to the visible entry area.

#new-sub-unit-fields.hidden
  = f.fields_for :sub_units, SubUnit.new, child_index: 'new_sub_unit' do |f_sub|
    = render 'sub_unit_fields', f: f_sub

Line #1: hide the div.

Line #2: use fields_for to generate the proper field id and name attributes so that it is submitted as a child object to our Organization. Notice the SubUnit.new? That prevents this block from iterating over all the @organization.sub_units that may be built, either as a new object (controller line #5), or when re-rendered due to a validation error with @organization.

Line #2: don’t forget the child_index: ‘new_sub_unit’ option! Without it, rails will attempt to index the fields id and name attributes with numbers, which in this case would be 0 (zero), and mess up the prior sub_unit fields. IOW, you will end up with two params[:organization][:sub_units_attributes][0] elements.

If you don’t understand all the details, take a few minutes and read the ActiveRecord::NestedAttributes::ClassMethods.

Now for some JS magic:

jQuery ->
  $('.well.sub-units').on('click', 'a.remove-sub-unit-button', ->
      remove_sub_unit(@)
    )

  $('.add-sub-unit-button').click ->
    add_sub_unit(@)

  add_sub_unit = (link) ->
    new_sub_unit = $(".hidden#new-sub-unit-fields").html()
    new_id = new Date().getTime()
    regexp = new RegExp("new_sub_unit", "g")
    $(link).closest('.add-sub-unit').before(new_sub_unit.replace(regexp, new_id))
    $(link).closest('.add-sub-unit').prev().find('input[type=text]').focus()

  remove_sub_unit = (link) ->
    $(link).prev("input[type=hidden]").val("1")
    $(link).closest(".control-group").hide()

Pretty simple, bind to the click events of the add-sub-unit-button and remove-sub-unit-button to functions.

add_sub_unit function copies the new-sub-unit-fields div, replacing the text of ‘new-sub-unit’ in the id and name attributes of the input/label elements with an integer.

remove_sub_unit function hides the input field group, and set the ‘_destroy’ hidden field to “1″ (‘true’ also works) so that it will not be created when the form is submitted.

Inspiration for this JavaScript goes to Ryan Bates.

Status Check

At this point we have a parent model, Organizations, with nested attributes for children SubUnits. When creating a new Organization, you can add and remove SubUnits. The entire relationship is submitted with a single form post.

Eliminate Duplicates in the DOM

Everyone else does it in model validations, manipulation of the params hash, or some other convoluted way. But I decided to eliminate duplicates before the submission of the parent form. Pretty easy, actually.

jQuery ->
  $('a.create-organization-button').click ->
    # remove duplicate form values, then submit the form
    uniqueNames = []
    $.each($('.controls.sub-unit input[type=text]'), (i, el) ->
        if $.inArray($(@).val(), uniqueNames) == -1
          uniqueNames.push($(@).val())
        else
          $(@).parent().find('input[type=hidden]').val("true")
      )
    $(@).closest('form').submit()

When the Create Organization button is clicked, the above JavaScript loops through all the SubUnit form field elements, marking duplicate entries hidden ‘_destroy’ field with ‘true’, thus preventing them from being saved. Could you just remove the elements? Sure.

Inspiration for the JavaScript remove duplicates in an array to Roman Bataev in this post.

If you watch your logs, you’ll see that all the SubUnits attributes are submitted, but only those marked with the hidden field ‘_destroy’ == ‘false’ will be created.

Started POST "/organizations" for 127.0.0.1 at 2012-12-21 16:32:39 -0700
Processing by OrganizationsController#create as HTML
  Parameters: {"utf8"=>"✓", "authenticity_token"=>"Dkphnf9nkc+5cxqRgo7mkQLcz2nvxHIUxezlOPA85cA=", "organization"=>{"name"=>"My Org", "sub_units_attributes"=>{"0"=>{"name"=>"Unit1", "_destroy"=>"false"}, "1356132751848"=>{"name"=>"Unit1", "_destroy"=>"true"}, "1356132755193"=>{"name"=>"Unit2", "_destroy"=>"false"}, "new_sub_unit"=>{"name"=>"", "_destroy"=>"false"}}}}
   (3.5ms)  begin transaction
  SubUnit Exists (0.4ms)  SELECT 1 AS one FROM "sub_units" WHERE ("sub_units"."name" = 'Unit1' AND "sub_units"."organization_id" IS NULL) LIMIT 1
  SubUnit Exists (0.1ms)  SELECT 1 AS one FROM "sub_units" WHERE ("sub_units"."name" = 'Unit2' AND "sub_units"."organization_id" IS NULL) LIMIT 1
  SQL (28.4ms)  INSERT INTO "organizations" ("created_at", "name", "updated_at") VALUES (?, ?, ?)  [["created_at", Fri, 21 Dec 2012 23:32:39 UTC +00:00], ["name", "My Org"], ["updated_at", Fri, 21 Dec 2012 23:32:39 UTC +00:00]]
  SQL (2.1ms)  INSERT INTO "sub_units" ("created_at", "name", "organization_id", "updated_at") VALUES (?, ?, ?, ?)  [["created_at", Fri, 21 Dec 2012 23:32:39 UTC +00:00], ["name", "Unit1"], ["organization_id", 6], ["updated_at", Fri, 21 Dec 2012 23:32:39 UTC +00:00]]
  SQL (0.2ms)  INSERT INTO "sub_units" ("created_at", "name", "organization_id", "updated_at") VALUES (?, ?, ?, ?)  [["created_at", Fri, 21 Dec 2012 23:32:39 UTC +00:00], ["name", "Unit2"], ["organization_id", 6], ["updated_at", Fri, 21 Dec 2012 23:32:39 UTC +00:00]]
   (48.5ms)  commit transaction

The astute reader will also notice that the SubUnit model is attempting to validate the uniqueness of the name attribute, scoping it to a non-existant Organization. I admit it would be best to skip this validation, but I will leave that exercise to you, humble reader.

Sample App

What? You wanted a demo app on the GitHubs? You shall be rewarded, post haste.

Synopsis

The Good

• Submission of a parent Organization with children SubUnits utilizing nested attributes.
• Duplicate SubUnits are removed.
• Darn simple, easy to reproduce. Pretty darn unobtrusive, too.
• No funky helpers to jack some html into a link element.
• Is it better than Ryan Bates’ solution? No. Just simpler.

The Bad

• Only works on creating a new Organization. Does not work for editing an Organization with the ability to add additional SubUnits or destroy existing SubUnits. Future post?
• My JavaScript is not abstracted to make it easily reusable. Fork it, and submit a patch if you so desire.
• The SubUnit validation should be skipped when creating through an Organization.
• No fallback if JavaScript is disabled.

Additional Reading

• StackOverflow: validates_uniqueness_of in nested model rails, a great discussion of how to handle scoped validation when editing existing child attributes.
• Rails issue: validates_uniqueness_of and accepts_nested_attributes_for only validates existing records, macfanatic shows a nice way to handle the same issue.
• Rails pull request: Validates associated uniqueness for nested attributes. The paint is still wet on this one. Hopefully is stirs some discussion.
• Ryan Bates’ gem: nested_form.

TL;DR Dumped let{}, removed FactoryGirl associations, back to before(:all) and instance variable/FG.build pattern = super speedy tests. 

TL;DR.1 And read the docs.

Background

I need to test a fairly complex permission matrix at the model level. To properly test it, I need to build out several complete company structures, with a multitude of users at various authorization levels. And 200+ actual tests.

Being a fan of rspec’s let{}, I decide to use it copiously. 40 lines worth.

In these tests, I don’t really need to have persisted records, so using FactoryGirl.build_stubbed fits the bill here.

let(:company) { FactoryGirl.build_stubbed(:company)}

… an so on, 39 times. 

What I Found

I thought one particular spec was running a little slow. So I converted the FactoryGirl.build to the shiny new FactoryGirl.build_stubbed. No difference in time. So I decided to watch the test.log. Well, I quickly saw what was happening… it was persisting thousands of records.

But wait. I was using FactoryGirl.build_stubbed. Where were all these records coming from?

Problem #1

In most of my FactoryGirl factories, I was using ‘association :area‘, ‘association :store‘, and so on. Didn’t think much about these until yesterday.

Turns out that FactoryGirl will build/create and save those associated factories, even if you are using FactoryGirl.build or FactoryGirl.build_stubbed. Learned something new there. Honestly, I didn’t expect this behavior, but I understand why. Shoulda read the docs.

Now, the easy way around this is to pass into a FactoryGirl.create/build/build_stubbed a nil for the association, if it is not needed. Ala:

FactoryGirl.build_stubbed(:store, company: fg_company, area: nil)

Now it won’t build out the associated area. Alas, I had forgotten just one of these nil associations. And at the worst possible relationship level, the bottom. So every time one factory was built, it create the entire supporting structure above. Thus, every hit to an let(:invoice) builds an entire company structure from one single FactoryGirl.build_stubbed(:invoice) call.

But it get’s worse.

Problem #2

I love the let{}. But to be honest, I never read the docs on it. Well, I did read them yesterday. Relavent line being (emphasis added):

The value will be cached across multiple calls in the same example but not across examples.

Uh-oh. Let{} is like a before(:each). Which is what most specs need. But I don’t, not for this spec. I’m never modifying the AR records, just testing some methods within models, which don’t modify AR instances.

Resulting Big Problem

Ok, not really a problem. But certainly very, very inefficient.

By forgetting to nil an association in a FactoryGirld.build_stubbed, and with let{} recreating an entire company structure, to the database, for every 200+ test. Well, you get the picture. It’s slooooow. 22 seconds worth of slow.

Solution

You know I wouldn’t drag you along this far without a solution.

1. Just remove all the ‘association :model‘ statements from all FactoryGirl definitions. I know they are handy, but I want CONTROL over my factories. And just one small mistake can make a spec run many X-times longer.
2. Remove the let{} and replace with the good ol’ instance variable/build pattern.
3. Move all the instance variables into a before(:all).

before(:all) do

  @company = FactoryGirl.build_stubbed(:company)

  @store = FactoryGirl.build_stubbed(:store, company: company)

  … and so on, 38 times.

end

Note for step #1. It caused me to refactor some other specs as well. This turned out to be a good thing, as I was able to speed up several other specs, and add some clarity to those specs that required building out a company structure.

Results

2.5 seconds. Not too shabby.

After the refactoring for all tests, I dropped ~30 more seconds off the entire suite.

Hope this helps someone else out there improve the speed of their specs too.

I am happy to report that I have this script running as a daemon, logging every ElkM1 event into my database. And it runs for months without issue.

I will keep these instructions brief. If you have detailed questions, please ask in the comments and I’ll help the best I can.

Download

You can download all the scirpts, just click here.

Notables

1. If you don’t know a least a little perl and some MySQL basics, you may want to look elsewhere.
2. The script and accompanying files are designed to work in concert as a daemonized process.
3. Everything is logged into ‘elk_monitor.log’ in the same directory (or directory of your choosing) as the script. If you have a lot of passive infra-red motion detectors, you will want to monitor the log size.

Basic File Structure

elk_monitor.pl

This is the main script, it runs in a loop checking for new messages every second. You will need edit the %zonelist, %outputs, %areas near the top. Also, you will need to set some paths, look near the top of the file.

Required: ElkM1::Control, Log4perl

elk_monitor.sh

This is the shell script that controls elk_monitor.pl as a daemon. Setting up daemons can be complex as each system is different, so google around for some help.

elkm1.sql

A MySQL script to setup the tables and fields that the elk_monitor.pl script uses. You will need to add a database named ‘elkm1′. After that you can execute this script to create everything else for you.

lib/elkm1_db.pl

The database setting and basic sql commands are abstracted into this library. This is where you will need to set MySQL’s host, name, password, etc.

lib/file_tickler.pl

I use a custom ruby script to monitor the daemon. This library just touches a file every minute to let us know the elk_monitor.pl script is still running. Why? Well, I have had the script ‘freeze’ without exiting and most monitoring applications do not detect this. Obviously, this part is optional.

Conclusion

If you get all the settings right, she should run all day/week/month for you.

I and not a perl expert. Far from it. So I’m sure everything could use some tidying. If you do, please let me know and I’ll incorporate your changes.

But it got me thinking, there is another think I like to keep an eye on on our servers… log files. Oh, and I was looking for good excuse to play around with Sinatra. So, “with a one, and-a-two, and-a-three…” we have Sinatra-Tailer.

You can read all about it on the github page, but in short it simply performs a tail and displays the last X lines of the log file.

tail -n /path/to/my/log/file.log

Features

1. refreshes the list every X seconds, set by the user
2. only one config.yml file to edit
3. supports file globs, so you can grab a whole list of file with one line
4. specify the number of lines to show
5. completely unobtrusive js, because I’m cool?

Requirements

Sinatra framework (tested on 0.9.1.1, earlier may work)

I whipped this up pretty quickly so I’m sure there are a few bugs. There is some testing for a few unit tests, but nothing functional.

One word of warning, if you want to put this on a production server my recommendation is to put it on a separate port (like 9876) and for heaven’s sake, at a minimum use http basic authentication. From the sinatra readme:

  use Rack::Auth::Basic do |username, password|
    username == 'admin' && password == 'secret'
  end

Enjoy!

The Problem

Here in my development palace I have a couple of laptops that I use for development and an Ubuntu (hardy) server as a Rails/Rack sandbox that I run with Passenger. While I have always been able to serve up either a Rails or Sinatra project, I typically have 3 or 4 going at the same time. But I had to access them with urls like: http://192.168.0.2/project1 and http://192.168.0.2/project2.

So, what’s the problem, eh?

Well, for starters, you can’t do anything concerning subdomains. That’s a show stopper for many apps.

Second, it really messes with your environment variables like ["PATH_INFO"]. So if you do any routing and you expect the base url to be ‘/’, it won’t be. The root url will be ‘/projectx’. Bummer.

The Solution

To remedy the issues with non-tld virtual hosts (also called sub URIs?) we need to add the domains to the laptops and server, then add the virtualhosts on the server for apache. This means that I can now goto http://project1.ubuntu.remote url to get to my rails/rack app.

For reference, I am using the following:

• Laptops: Mac OS X, 10.5.7 and 10.4.11
• Server: Ubuntu Desktop 8.04LTS, Apache/2.2.8 (Ubuntu) mod_fastcgi/2.4.6 PHP/5.2.4-2ubuntu5.5 with Suhosin-Patch Phusion_Passenger/2.0.6

On Each Laptop

These instructions are for Mac OS X, but should be identical for your favorite flavor of *nix. We are going to add some friendly names to our ubuntu server using it’s ip address (192.168.0.2). In this example we will be able to access the root web documents using http://ubuntu.remote, and one of our Sinatra projects using http://project1.ubuntu.remote.

Important! Don’t use a name ending in ‘.local’. While it did work for me, I read about a few instances where some systems will not resolve domain names ending in .local outside the local machine. Also, don’t change anything else in your /etc/hosts file except to add the lines at the end.

mate /etc/hosts

# add the following line to the END of your /etc/hosts file and save
# note: there is a <space> character between the ip address and each host name
192.168.0.2 ubuntu.remote project1.ubuntu.remote

On The Server: Hosts File

Nothing will work until we tell the server machine that it can accept incoming traffic from our new friendly names. Similar to on the mac, we need to edit our /etc/hosts file but we will add a slightly different line. In this case we are telling the server that incoming traffic from ‘ubuntu.remote’ and ‘gems.ubuntu.remote’ are just names for the localhost (127.0.0.1).

sudo pico /etc/hosts

# add the following line to the end of our /etc/hosts file and save
# you can added after your existing 127.0.0.1 line if you wish
127.0.0.1 ubuntu.remote project1.ubuntu.remote

On The Server: VirtualHosts

As a final step we will need to add or change the virtual host definitions for your rails/rack project. Depending on your Apache setup or Linux distro, the default enabled site may be slightly different and you may have to adapt your virtual host file to your default setup.

First, in my /etc/apache2/apache.conf file, I have the following line near the end of the file. This was to eliminate a warning every time apache was started/restarted. It may affect your virtual host default, but shouldn’t, so add it if you get errors.

#added near end of /etc/apache2/apache.conf
ServerName localhost

Next we need to check our default virtual host setup to see how the NameVirtualHost is defined. We will duplicate that in each new virtual host that we add. The parts we are looking is the NameVirtualHost and VirtualHost near the top. They could be ‘NameVirtualHost *’ and ‘<VirtualHost *>’ or ‘NameVirtualHost *:80′ and ‘<VirtualHost *:80>’. See the pattern? We need to use the same definition in our new virtual files.

Let’s check our default virtual host setup:

cd /etc/apache2/sites-enabled
ls # your are looking for the name of your default site file

  total 0

  lrwxrwxrwx 1 root root 36 2009-02-27 18:49 000-default -> /etc/apache2/sites-available/default

cat /etc/apache2/sites-enabled/000-default

  NameVirtualHost *
  <VirtualHost *>
    ServerAdmin webmaster@localhost
  # snipped several lines #
  </VirtualHost>

On my system the NameVirtualHost is ‘*’, so that is what we need to use for the new virtual host. In this case, I am going to add a virtual host file for a rack based project. It’s a Sinatra app, but that doesn’t matter as this will work for any rack based project, even a rails/rack project (since rails 2.2.2?).

Also, I like using the Apache2 system to enable and disable sites. It’s clean, easy to use, and if any apache admin comes along they will know exactly what is going on.

It’s also work mentioning that you should disable or delete any existing virtual host files that you were using previously.

cd /etc/apache2/sites-available
sudo pico gems

# enter this as your virtual host setup
<VirtualHost *>
  ServerName project1.ubuntu.remote

  DocumentRoot "/path/to/your/application/project/public"

  RackEnv production
  <directory "/path/to/your/application/project/public">
    Order allow,deny
    Allow from all
  </directory>
</VirtualHost>

# save the file and reload apache

sudo /etc/init.d/apache2 reload

The Fun Part

Assuming you saw no errors when you reloaded apache, you should be able to go to your new urls see both the root files and your rack application.

http://ubuntu.remote

http://project1.ubuntu.remote

Dyn-O-Mite!

Bonus Points!

For extra credit, let’s say you have admin access to your router, and you are one of those gotta-have-control-of-everything dudes (or dudettes) so you installed a 3rd party firmware. You’re in luck! You can probably add some custom entries in your DNS and you don’t have to edit the /etc/hosts files on your laptop.

I installed Tomato firmware on my Linksys wireless router. Tomato uses Dnsmasq with allows you to set internal host names.

Maybe I’ll cover that in another post.

About a year ago, James Russo released a script on Cocoontech to monitor and control your Elk M1 from a perl script. You can read the forum post for more details. Thanks to James and other Cocoontech members, it works fairly well.

But there have been no updates or bug fixes in over a year. Not wanting to relive my perl days (sorry, I never really liked perl), I decided to revive the project and give it a new home. I asked James for permission to take over the project and he gracefully agreed.

ElkM1::Control New Home on Github

Go check it out! ElkM1::Control on github.

Why github? First, I have stopped using SVN. And sourceforge, ElkM1::Control’s original home, doesn’t support git. Second, github makes it too easy to fork a project and make changes yourself, then push them back up so that I can integrate those changes. You really should try git if you haven’t before. And you don’t need git to download ElkM1::Control and install it.

Updates and Bug Fixes!

You read that right, I have made a few bug fixes and added a couple of new features. I have been running ElkM1::Control on my Ubuntu Hardy server for about a month with no problems. I have also run and do some debugging on OS X (10.5.x).

I also changed the version numbering system to the more common major.minor.release notation. We are not at version 0.1.0.

Quick Installation Instructions

1. Goto the project home page and click the download button. Select the ZIP version (for some reason the TAR doesn’t work sometimes).
2. Follow the README file, don’t forget the PREREQUISITES section. For those who don’t rtfm…
3. From your favorite shell, you may need to add sudo in front of each: ‘perl Makefile.PL’
4. ‘make’
5. ‘make test’
6. Then to install: ‘make install’

Next, you’ll need a little script to get going. There are several scripts posted on Cocoontech, but this one should get you started:

# Example 2: Display all M1 messages
use ElkM1::Control;
    my $elk = ElkM1::Control->new(host => '192.168.0.251', port => 2101);
    while (1) {  # Loop forever
        while (my $msg = $elk->readMessage) { # Read the M1's messages
                print $msg->toString;  # Print the messages
        }
    }

I shouldn’t disrespect restful authentication much as she has been with me for over a year now. But every time I had to install, setup, and get the basics working in RA I couldn’t help gnashing my teeth. I jumped on the RA bandwagon like so many other Rails developers looking for an authentication system that just and move on to more important things.

Enter Authlogic by Ben Johnson of BinaryLogic. By luck, I was starting a new rails app this week, so I decided to take Authlogic out for a test drive. Following Ben’s Tutorial: Authlogic Basic Setup I had a basic login/logout/session management system up and running in a ridiculously little amount of code. The best part of Authlogic is that it truly get’s out of my way and provides me with what I need… a robust and secure methodology of authentication and session management.

The benefits of Authlogic are:

• It’s a plugin and a gem. When Ben pushes an update, getting the latest release is super simple.
• It’s a plugin and a gem. This keeps the authentication code separate from your codes, the way it should be.
• Session are treated like ActiveRecord objects. This is just as cools as it sounds and is very Rails-like.
• Better security. Authlogic uses a non-reversible token that is changed on every session initiation and password change, thus virtually eliminating session persistence and brute force session attacks.
• Ben Johnson. Ben knows what he is doing and has been quickly releasing updates.
• Ben Johnson. Sorry for the repetition, but Ben also has a nice series of tutorials with supporting project code you can download.
  • Tutorial: Reset passwords with Authlogic the RESTful way
  • Tutorial: Authlogic Basic Setup

I had several years of photos that I needed to identify and remove the duplicate. Instead of manually combing through 12,000 (read Long Story below) and before carpal tunnel set in, I needed a script to help me out. My situation may or may not be unique, so this script may not work 100% out-of-the-box for you, but it should get you started.

To use:

1. Download and unzip the script
2. Double-click the script to open in Script Editor
3. Go into iPhoto and select a group of photos you want to compare
4. Switch back to Script Editor and run the script
5. Don’t Touch Anything! Just let the script finish, it could take a while if you are comparing a lot of photos
6. After the script is done, go back into iphoto and search for “duplicate”
7. You can highlight all the duplicates and delete them or move them some place safe

Photos are considered a duplicate if:

1. both heights match
2. both widths match
3. the photo date in iPhoto match, this is typically the EXIF creation date

Long Story:

Breakfast from a Can? WTF!

At first, I honestly thought it was a joke, but I was compelled to stop and pick up the can and watch our demo maven squirt batter out of a can onto the griddle. I did try one, and it tasted OK, but nothing better than what I make for the kids on weekends. That’s when the whole thing really started to bother me.

Ridiculously High Cost!

I doubt one can could hold its own against my two boys. And the three pack can was something like $7.00 (please comment if you know the real price). Geeze Louise that is expensive. According to the label each can will make 28 – 4in. pancakes. I have some pretty serious doubts about that claim. Those must be some darn thin pancakes.

By their own admission, there is only 2.25 cups of batter in each can. When I make pancakes, I use a ladle that is 6oz. which I reckon results in 4oz. per pancake. And each of my boys will eat 3 to 4 of those suckers, without batting an eye. That comes out to ONE CAN per child. And my kids are not the video game, boob tube species either. In fact both are a tad on the skinny side.

Could You Be More Environmentally Unfriendly or What?

Don’t prattle on to me about how steel cans are recyclable. The amount of energy to produce and recycle those cans, the extra weight of shipping, the added shelf space, not to mention that you must keep it refrigerated are all energy wastes. And completely unnecessary.

My pancakes come in paper bags… um, flour, pinch of baking soda and baking powder, maybe some buttermilk if I have it around, , dash of salt, and an egg or two. Not much to recycle there. Even if you go the pancake mix route, all you have is one small box or plastic (recyclable) bag. Even better, Elise has a great recipe for Blueberry Buttermilk Pancakes over at Simply Recipes. Yum.

All that steel in the name of convenience is a shameful waste.

Are People Really That Lazy?

That was probably my first thought. Have people become so darn lazy that can’t mix a little water with some batter mix and make semi-homemade pancakes? I hope not. For crying in a bucket, how hard is it to mix up a little batter!

If you poke around on the blaster site, they have so-called testimonials from overly exuberant customers espousing how much time Batter Blaster has saved them and how convenient it was. All I can picture is one of those self-absorbed parents, squirting goo out of a can, while yapping on their cell phone, kids with permanent carpel tunnel jamming out on their NDS,  while cooking some pancakes. Woot, ain’t multi-tasking great. America, we sure have come a long way baby.

Let me put a better vision in your mind… you take a box of Krusteaz Pancake & Waffle Mix out of your cupboard, let your son or daughter measure out a couple of cups of mix, show them how to calculate the appropriate amount of water to add, topping it off with a short mixing lesson. You just made something together, and they enjoyed spending time with you, and they will enjoy cooking because they actually did something useful.

Wow, educating your kids about cooking and math all while you develop a real relationship with your kids FTW! Flipping amazing.

BTW, they sell the Krusteaz mix in big bags at Costco for around the same price as the blasters. I can only guess the hundreds of pancakes you can make with that bag, plus you’ll forgo chucking enough steel to build a Yugo.

Please, Please, Please…

Don’t by this product. It exists for only the wrong reasons. Do what is better for your wallet, your planet, and your family by exercising your brain and hands. Trust me, your kids will like you better for it.

If you have a favorite pancake or waffle recipe, please add it in the comments below.

I feel better now℠

Update 12/2/08: Fixed in Rails 2.2! (read more)

The error that I received was thus:

ActionView::TemplateError (undefined method `length' for #) on line #83 of dashboard/index.html.erb:


Fortunately, someone has submitted a ticket to Rails core. I hope it’s applied in the Rails 2.2.0 release.

Current Method, Done Busted

As of Rails 2.1.0, this is the current method (Rails 2.0.2 is similar, and also broken).

<br />
# File actionpack/lib/action_view/helpers/text_helper.rb, line 49<br />
def truncate(text, length = 30, truncate_string = "...")<br />
if text<br />
l = length - truncate_string.chars.length<br />
chars = text.chars<br />
(chars.length > length ? chars[0...l] + truncate_string : text).to_s<br />
end<br />
end<br />

The problem is that chars method called on the string object (truncate_string) returns an <Enumerable::Enumerator> object. And according to the Ruby 1.8.7 RDoc, there is no ‘length’ method in Enumerable::Enumerator. To be honest, I can’t find the ‘chars’ method in any of the Ruby 1.8.6 docs or 1.8.7 docs. I guessing that it may have been Rails method at some time.

Fix #1

The fix is to get rid of all the chars methods. On the bug ticket, the author gives his fix, but you are going to have to monkey-patch rails, or change the method name.

<br />
def truncate(text, length = 30, truncate_string = "...")<br />
if text<br />
l = length - truncate_string.chars.to_a.length<br />
chars = text.chars<br />
(chars.to_a.length > length ? chars.to_a[0...l].to_s + truncate_string : text).to_s<br />
end<br />
end<br />

Fix #2 (mine, tiny bit better?)

I’m not exactly sure why the string needs to be converted to an array, when the length function works just dandy on string objects. So I added this to my application_helper.rb file. Also, in the submitted patch, the result of the ternary is converted to a string (.to_s), when all the resulting methods of the ternary return strings. Unnecessary IMHO and probably left over from when the string object was converted to an enumerable. Note that I started with the Rail 2.0.1 version, so it’s slightly different than if I started with the 2.1.0 version.

<br />
def truncate_string(text, length = 30, truncate_string = '...')<br />
if text.nil? then return end<br />
l = length - truncate_string.length<br />
text.length > length ? text[0...l] + truncate_string : text<br />
end<br />

Yeah, yeah, I could have monkey-patched the TextHelper module, but why tempt fate if you don’t have to. A quick find/replace on ‘truncate’ to ‘truncate_string’ is all that was necessary. Works for me.