Scratch
After seeing a presentation (by Gary Haran) on Rails engines and reading a certain blog post, I decided that enough was enough! I had some Rails induced itches that needed some much needed relief. Thus here is Scratch, a library which tries to fix a bunch of Rails’ most insignificant shortcomings.
Features
- The normalize model mixin
- A few core extensions
Installation
Simply add Scratch to your Gemfile and bundle it up:
ruby
gem 'scratch'
Usage
Mixins (or Concerns if you prefer the Rails vocabulary)
These mixins are included in ActiveRecord with this gem, they could (theoretically) be used inside any other classes, but this hasn’t been tested (nor documented) yet.
Normalize
The normalize method help you create callbacks to normalize some
attributes in a simple declarative manner.
Say you’d like to set all blank attributes to nil before validation, you could do:
ruby
normalize before: :validation, when: :blank?, set: nil
The before option default to :validation so it can be omitted in
that case. You can also pass a block to normalize that will be given
the value of the attribute and should return it’s normalized form:
ruby
normalize { |value| value.strip }
The block in that example is a common pattern that can be replaced by
the method option:
ruby
normalize method: :strip
There’s two specialized mixins which are variant of the above examples…
Stripify
The stripify method will strip all attributes, it also support all of
normalize options. Here’s an example using the except option:
ruby
stripify except: :foo
Nilify
Don’t like odd numbers, here’s a solution:
ruby
nilify only: [:foo, :bar], when: :odd?, before: :save
Core Extensions
Array
Want to use join for user facing stuff but doesn’t want to clean up
the array yourself, use strip_join:
ruby
[1, 2, nil, '', ' ' , ' 3 '].strip_join ', '
#=> "1, 2, 3"
Hash
Have many keys to look-up and need the first one available, use fetch_or:
ruby
h = { a: 1, b: 2, c: 3 }
h.fetch_or :e, :d, :c
#=> 3
# also support a `default` option...
h.fetch_or :x, :y, :z, default: nil
#=> nil
# when no default is given, act like `fetch` and raise a `KeyError`
You’re stuck with a hash having arrays as values and need to invert it?
ruby
h = { west_coast: %w(WA OR CA AZ), east_east: %w(ME VT NY NJ) }
y = h.invert_splat
y['NJ']
#=> :east_coast
License
This project rocks and uses MIT-LICENSE!