ar2json

• https://github.com/cesario/ar2json

DESCRIPTION:

ar2json provides a to_json method on an ActiveRecord::Relation object. This method will return a JSON representation, in a String object, of the resultset.

Why is this useful? Because the JSON is mostly outputed by your database engine.

TODO

• User.scoped.to_json and User.all.to_json should return the same data structure
• Pivot the resultset in the DB to have a single value returned by the DB (it's now done in to_json.rb)

FEATURES/PROBLEMS:

• Tested with SQLite and PostgreSQL

SYNOPSIS:

Rails 3 Configuration

In the project's Gemfile add

gem 'ar2json'

Usage

Say Product is your model:

class Product < ActiveRecord::Base
end

If your database looks like this

            +---------------------------------+
            |ID  Name                Color    |
            |---------------------------------|
            | 1  Foo                 blue     |
            | 2  Bar                 red      |
            | 3  Baz                 blue     |
            +---------------------------------+

Product.where(:color => 'blue').to_json will return

[
  { "id": "1", "name": "Foo", "color": "blue" },
  { "id": "2", "name": "Baz", "color": "blue" }
]

You can also tell to_json to only use the columns you specify:

#=> Product.where(:color => 'blue').to_json([:id])

[
  { "id": "1" },
  { "id": "2" }
]

Some benchmark now

Lab

➜  uname -a
[...] Darwin 10.7.0 Darwin Kernel Version 10.7.0 [...]

SQLite3

                                      user     system      total        real
User.scoped.to_json                   0.230000   0.010000   0.240000 (  0.246796)
User.all.to_json                      2.320000   0.080000   2.400000 (  2.430381)
User.where(:id => [1,2]).to_json      0.180000   0.010000   0.190000 (  0.182994)
User.where(:id => [1,2]).all.to_json  0.300000   0.020000   0.320000 (  0.322805)
User.where(:id => 1).to_json          0.160000   0.010000   0.170000 (  0.196703)
User.where(:id => 1).all.to_json      0.220000   0.010000   0.230000 (  0.230023)

PostgreSQL

                                      user     system      total        real
User.scoped.to_json                   0.080000   0.010000   0.090000 (  0.223884)
User.all.to_json                      2.200000   0.090000   2.290000 (  2.393640)
User.where(:id => [1,2]).to_json      0.140000   0.010000   0.150000 (  0.256728)
User.where(:id => [1,2]).all.to_json  0.270000   0.020000   0.290000 (  0.368916)
User.where(:id => 1).to_json          0.140000   0.010000   0.150000 (  0.249957)
User.where(:id => 1).all.to_json      0.200000   0.010000   0.210000 (  0.277496)

REQUIREMENTS:

• Rails
• ActiveRecord >= 3.0.0
• A database :D

INSTALL:

• (sudo) gem install ar2json

LICENSE:

(The MIT License)

Copyright (c) 2011 Franck "Cesario" Verrot

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.