Ika

Ika implements the function that export/import ActiveModel data with json. Ika also supports carrierwave.

Installation

In Rails, add it to your Gemfile:

gem 'ika'

Usage

You can use export or import method on your model or relation.

Example

In case: Group has many tags and User belongs to multiple groups with GroupUsers such as below.

class User < ActiveRecord::Base
  has_many :group_users
  has_many :groups, through: :group_users
end

class GroupUsers < ActiveRecord::Base
  belongs_to :user
  belongs_to :group
end

class Group < ActiveRecord::Base
  has_many :group_users
  has_many :users, through: :group_users
  has_many :tags
end

class Tag < ActiveRecord::Base
  belongs_to :group
end

Now you can export with export method on your model or relation and import with import method on your model.

require 'json'
# with no options

JSON.parse User.export
# => [{"id":1,"name":"iruca3"},{"id":2,"name":"inkling"}]
JSON.parse User.where(id: 1).export
# => [{"id":1,"name":"iruca3"}]
JSON.parse User.find(id: 2).export
# => {"id":2,"name":"inkling"}

# with include option
JSON.parse User.export(include: :groups)
# => [{"id":1,"name":"iruca3","groups":[{"id":1,"name":"aqutras"},{"id":2,"name":"Splatoon"}]},{"id":2,"name":"inkling","groups":[{"id":2,"name":"Splatoon"}]}]
data = JSON.parse(User.find(id: 1).export(include: [{groups: [:tags]}]))
# => {"id":1,"name":"iruca3","groups":[{"id":1,"name":"aqutras","tags":[{"id":1,"name":"Company"}]},{"id":2,"name":"Splatoon","tags":[{"id":2,"name":"Game"},{"id":3,"name":"Inkling"}]}]}

# import (id, created_at and updated_at are completely imported with the same value)
User.destroy_all
Group.destroy_all
Tag.destroy_all
User.import(data)

# sync mode is available.
User.import(User.where(id: 1).export, sync: true)
User.exist?(id: 2)
# => false

Sync mode

Sync mode performs that ika deletes all data of importing models. For example, if exporting data includes that id is 1 and 2, and there are already exists data that id is 1, 2 and 3, sync importing deletes the data of id 3.

Others

DO NOT USE sync mode if you are using include option.
If the same id exists, Ika uses UPDATE.
Uploaded files by carrierwave will be checked their md5 hash and do nothing if they exist and md5 is matched.
If there already exists import or export methods, you can use ika_import or ika_export methods.

Contributing

Test

You need to run bundle exec rake db:create db:migrate on spec/dummy before testing.

ika

Development

Runtime

Ika