The attached patch lets you find a record by a string or number in any column:

User.find_by_anything('carla')
User.find_by_anything('email@domain.de')
User.find_by_anything(10023)

There's also a bang variant that raises ActiveRecord::NotFound if no record matches the given value:

User.find_by_anything!('carla')

Boolean and binary columns are excluded from the search because that would be crazy.

I recommend copying the attachment to features/support/find_by_anything.rb, since it is most useful in Cucumber step def...

This is a very general introduction to MV* Javascript frameworks. This card won't tell you anything new if you are already familiar with the products mentioned in the title.

As web applications move farther into the client, Javascript frameworks have sprung up that operate on a higher level of abstraction than DOM manipulation frameworks like jQuery and Prototype. Such high-level frameworks typically offer support for client-side view rendering, routing, data bindings, etc. This is useful, and when you write a moderately complex Javascript ...

Ever seen this error when using Graticule?

Numerical argument out of domain - acos

Similarly to the to_sql problem for some edge cases, Graticule::Distance::Spherical.distance (and possibly those of Graticule's other distance computation classes) is subject to Float rounding errors.

This can cause the above error, when the arc cosine of something slightly more than 1.0 is to be computed, e.g. for the (zero) distance b...

Possible Reason 1: parallel_tests - running more processes than features

If you run old versions of parallel_tests with more processes than you have Cucumber features, you will get errors like this in unexpected places:

This is a bug caused by multiple processes running the same features on the same database.

The bug is fixed in versions 0.6.18+.

Possib...

If Sunspot does not work and fails with a backtrace similar to this:

/project/shared/bundle/ruby/1.8/gems/rsolr-1.0.6/lib/rsolr/client.rb:227:in `adapt_response'
/project/shared/bundle/ruby/1.8/gems/rsolr-1.0.6/lib/rsolr/client.rb:164:in `execute'
/project/shared/bundle/ruby/1.8/gems/rsolr-1.0.6/lib/rsolr/client.rb:158:in `send_and_receive'
(eval):2:in `post'

then the schema.xml that is shipped with Sunspot is not loaded into Solr correctly.

Often the latter can be found in /etc/solr/conf/schema.xml. So copy Sunspo...

Most of the JavaScript snippets have code that manipulates the DOM. For that reason dom manipulating javascript code should have been executed after the DOM has loaded completely. That means when the browser has finished HTML parsing and built the DOM tree. At that time, you can manipualte the DOM although not all resources (like images) are fully loaded.

The following snippets show how you can do this with plain JavaScript, jquery or prototype ([dom ready ...

This describes all the steps you'll need to get Solr up and running for your project using the Sunspot gem.

Prepare Sunspot on your development machine

What you want in your Gemfile:

gem 'sunspot_rails'
gem 'sunspot_solr'
gem 'progress_bar' # for sunspot:solr:reindex

Now define what should be indexed within Solr from your ActiveRecord models, e.g.,

class Article << ActiveRecord::Base

  searchable do
    text :title
 ...

Gem to get Rails 3's new ActiveRecord query interface (where, order) and the new scope syntax (chaining scope definitions) in Rails 2.

You also get #to_sql for scopes.

Use the command geordi migrate to migrate your databases and to prepare them before running tests. The abbrevation geordi m works as well.

• It will run rake db:migrate if parallel_tests does not exist in your Gemfile
• Otherwise it runs b rake db:migrate and then executes b rake parallel:prepare if parallel_tests was found in your Gemfile.

Removing features and merging those changes back can be painful. Here is how it worked for me.\
tl;dr: Before merging back: reinstate reverted features in a temporary branch, then merge that branch.

Scenario

Consider your team has been working on several features in a branch, made many changes over time and thus several commits for each feature.\
Now your client wants you to deploy while there are still stories that were rejected previously and can't be deployed.
...

Our gitpt script to generate git commits from Pivotal Tracker stories has been tweaked and polished and is now part of the geordi gem.

Install the freshly released version 0.7 now:

gem install geordi

This update will bring you commit with an initial "setup wizard" (that asks for your PT API key and initials) and prettier output: stories are colored by their state and thos...

When selecting records in a date range, take care not to do it like this:

start_date = Date.parse('2007-05-01')
end_date = Date.parse('2007-05-31')
LogItem.where(:created_at => start_date .. end_date)

The problem is that created_at is a datetime (or Time in Ruby), while start_date and end_date are simple dates. In order to make sense of your query, your database will cast your dates to datetimes where the time component is 00:00:00. Because of this the query above will lose records created from `2007-05-31 00:00:0...

Basically, you now need to know if your project uses a "real" time zone or :local, and if config.active_record.time_zone_aware_attributes is set to false or not.

• With time zones configured, always use .current for Time, Date, and DateTime.

  ActiveRecord attributes will be time-zoned, and .current values will be converted properly when written to the database.
  Do not use Time.now and friends. Timezone-less objects will not be converted properly when written to the database.

• With no/local time zone use Time.now, `...

The tagged_with scope comes with many awesome options to modify your search:

User.tagged_with("awesome", "cool")                     # Users that are tagged with awesome and cool
User.tagged_with("awesome", "cool", :exclude => true)   # Users that are not tagged with awesome or cool
User.tagged_with("awesome", "cool", :any => true)       # Users that are tagged with awesome or cool
User.t...

This might seem obvious, but I'm rejecting stories because of this on a regular basis.

Whenever a list (e.g. an index of records or the options of a select box) is visible in the UI that list must be sorted. Unsorted lists are completely unusable once they contain more than 5 items.

The unix command line tool less is a good choice for browsing logfiles. In the standard configuration, though, it does not interpret the escape sequences used in the rails logfiles. To enable this type:

less -R my_logfile.log

You can also have an alias to save yourself the typing

alias less='less -R'

When internationalizing your Rails app, you'll be replacing strings like 'Please enter your name' with t('.name_prompt'). You will be adding keys to your config/locales/*.yml files over and over again. Not to miss any key and place each at the right place is a challenging task.

The gem i18n-tasks has you covered. See its README for a list of things it will do for you.

Note

The i18n-tasks gem does not understand aliases and will duplicate all referenced data when it writes locales. If yo...

For university I have to stay up-to-date with lecture documents. Since my university doesn't offer RSS feeds, I wrote a little script that collects files from web pages.

You want this, if you have several web pages that offer downloads that you don't want to check manually. Just register the URL and a CSS snippet to retrieve the files in the attached script and run it – it will fetch all your files. It will store all files in a single place or sort them into respective directories.

Edit the header of the file (providing your data), save it...

The SQL code generated by Graticule's spherical distance computation is insufficient and can lead to NULL distances in edge cases.

The reason for this is that MySQL is performing several sine and cosine computations which can result in slight rounding errors -- which is usually okay. Rarely, though, for the exact center of the given circle, it is then asked to compute the arc cosine of a result like 1.0000000001.

Since this i...

Seems like a useful gem for cases where ActiveRecord is overkill but you don't want to do everything by hand either.

Using rename_column, remove_column, etc. more than once in a migration makes that migration run slower than it should. Use change_table instead.

Consider this migration:

add_column :users, :name, :string
remove_column :users, :first_name
remove_column :users, :last_name
rename_column :users, :cool, :awesome

Migrating in this case means that all those commands are processed step by step, causing 4 SQL statements to change the table. In turn, your database needs to modify the table structure 4 times. When working on hu...

For performance improvements (and to remove the need for eager loading), the ActsAsTaggableOn gem supports caching your tag lists directly in your model. To enable this, simply add a cached_tag_list column to your table.

Example:

class Company < ActiveRecord::Base
  acts_as_taggable_on :categories
end

The cache column has to be named cached_category_list.

Existing data

If you already have existing data, you have to save all records with tags once, after you've added the ...