Introduction

# == Schema Information
#
# Table name: users
#
#  id              :integer          not null, primary key
#  email           :string
#  profile         :jsonb
#  contact_details :json
#  created_at      :datetime         not null
#  updated_at      :datetime         not null
#

class User < ActiveRecord::Base
  has_json_attributes_on :profile, {
    firstname: {type: 'String', validates: {presence: true, length: {maximum: 20, minimum: 3}}},
    lastname: {type: 'String', validates: {presence: true, length: {maximum: 20}, exclusion: {in: %w(admin ruler)}}},
    age:  {type: 'Integer', default: ->{rand(36)}, validates: {presence: true, numericality: true,  inclusion: { in: 18..35 }}},
    birthday: {type: 'Date', default: ->(u){ u.age.years.ago.to_date}, validates: {presence: true}},
    salary: {type: 'Decimal', validates: {presence: true}},
    married: {type: 'Boolean', default: ->(u){ u.age > 25 ? true : false}},
    kids_names: {type: 'Set'},
    companies: {type: 'Array'},
    extra: {type: 'Hash'}
  }

  has_json_attributes_on :contact_details, {
    google: {}, # default is type is 'String'
    facebook: {type: 'String'},
    twitter: {type: 'String'}
  }
end


User #=> User(id: integer, email: string, profile: jsonb, contact_details: json, created_at: datetime, updated_at: datetime)
u = User.new
=> #<User:0x007fa28542a318
 id: nil,
 email: nil,
 profile: #<User::ProfileDynamicType:0x007fa285429dc8 @age=23, @birthday=Thu, 07 Jan 1993, @companies=[], @extra={}, @firstname=nil, @kids_names=#<Set: {}>, @lastname=nil, @married=false, @salary=nil>,
 contact_details: #<User::ContactDetailsDynamicType:0x007fa28474c060 @facebook=nil, @google=nil, @twitter=nil>,
 created_at: nil,
 updated_at: nil>

u.age       #=> 23
u.profile.age #=> 23

u.age = 30
u.age       #=> 40
u.profile.age #=> 40

u.age = 25
u.age       #=> 25
u.profile.age #=> 25

u.married   #=> false
u.married = 'T'
u.married   #=> true
u.salary    #=> nil
u.salary = '202829.6699'  # Type casted
u.salary    #=> #<BigDecimal:7fa08a618ac8,'0.2028296699E6',18(27)>  #Type casted

u = User.new(age: 26)
u.age       # => 26
u.married   # => true
u.birthday  # => Sun, 07 Jan 1990

u.married = 'N'
u.married   #=> false
u.salary = '202829.6699'  # Type casted
u.salary    #=> #<BigDecimal:7fa08a618ac8,'0.2028296699E6',18(27)>  #Type casted
u.kids_names = ['jane', 'jane', 'solly']
u.kids_names #=> #<Set: {"jane", "solly"}>
u.companies = "Apple"
u.companies  #=> ["Apple"]
u.companies = ['Apple', 'Google']
u.companies  #=> ["Apple", "Google"]
u.extra = {x: 3}
u.extra  #=> {:x=>3}

u = User.new()
=> #<User:0x007fa2853e37d8
 id: nil,
 email: nil,
 profile: #<User::ProfileDynamicType:0x007fa2853daea8 @age=31, @birthday=Mon, 07 Jan 1985, @companies=[], @extra={}, @firstname=nil, @kids_names=#<Set: {}>, @lastname=nil, @married=true, @salary=nil>,
 contact_details: #<User::ContactDetailsDynamicType:0x007fa2853b1530 @facebook=nil, @google=nil, @twitter=nil>,
 created_at: nil,
 updated_at: nil>

u.valid?  #=> false
u.errors
=> #<ActiveModel::Errors:0x007fa285313038
 @base=
  #<User:0x007fa2853e37d8
   id: nil,
   email: nil,
   profile: #<User::ProfileDynamicType:0x007fa2853daea8 @age=31, @birthday=Mon, 07 Jan 1985, @companies=[], @extra={}, @firstname=nil, @kids_names=#<Set: {}>, @lastname=nil, @married=true, @salary=nil>,
   contact_details: #<User::ContactDetailsDynamicType:0x007fa2853b1530 @facebook=nil, @google=nil, @twitter=nil>,
   created_at: nil,
   updated_at: nil>,
 @messages={:firstname=>["can't be blank", "is too short (minimum is 3 characters)"], :lastname=>["can't be blank"], :salary=>["can't be blank"]}>

u.attributes = {firstname: 'James', lastname: 'King', salary: '1.6789'}
u.valid?  #=> true
u.save
(2.1ms)  BEGIN
SQL (2.7ms)  INSERT INTO "users" ("profile", "contact_details", "created_at", "updated_at") VALUES ($1, $2, $3, $4) RETURNING "id"  [["profile", "{\"firstname\":\"James\",\"lastname\":\"King\",\"age\":31,\"birthday\":\"1985-01-07\",\"salary\":\"1.6789\",\"married\":true,\"kids_names\":[],\"companies\":[],\"extra\":{}}"], ["contact_details", "{\"google\":null,\"facebook\":null,\"twitter\":null}"], ["created_at", "2016-01-07 08:58:44.945408"], ["updated_at", "2016-01-07 08:58:44.945408"]]
(0.9ms)  COMMIT
=> true

u.salary = '202829.6699'  # Type casted
u.salary    #=> #<BigDecimal:7fa08a618ac8,'0.2028296699E6',18(27)>  #Type casted
u.kids_names = ['jane', 'jane', 'solly']
u.kids_names #=> #<Set: {"jane", "solly"}>
u.companies = "Apple"
u.companies  #=> ["Apple"]
u.companies = ['Apple', 'Google']
u.companies  #=> ["Apple", "Google"]
u.extra = {x: 3}
u.extra  #=> {:x=>3}

u.facebook = "https://facebook.com/someusername"
u.facebook #=> "https://facebook.com/someusername"

u
=> #<User:0x007fa2853e37d8
 id: 2,
 email: nil,
 profile:
  #<User::ProfileDynamicType:0x007fa2853daea8
   @age=31,
   @birthday=Mon, 07 Jan 1985,
   @companies=["Apple", "Google"],
   @extra={:x=>3},
   @firstname="James",
   @kids_names=#<Set: {"jane", "solly"}>,
   @lastname="King",
   @married=true,
   @salary=#<BigDecimal:7fa28ba358b0,'0.2028296699E6',18(27)>>,
 contact_details: #<User::ContactDetailsDynamicType:0x007fa2853b1530 @facebook="https://facebook.com/someusername", @google=nil, @twitter=nil>,
 created_at: Thu, 07 Jan 2016 08:58:44 UTC +00:00,
 updated_at: Thu, 07 Jan 2016 08:58:44 UTC +00:00>

 u.save
   (0.2ms)  BEGIN
  SQL (0.4ms)  UPDATE "users" SET "profile" = $1, "contact_details" = $2, "updated_at" = $3 WHERE "users"."id" = $4  [["profile", "{\"firstname\":\"James\",\"lastname\":\"King\",\"age\":31,\"birthday\":\"1985-01-07\",\"salary\":\"202829.6699\",\"married\":true,\"kids_names\":[\"jane\",\"solly\"],\"companies\":[\"Apple\",\"Google\"],\"extra\":{\"x\":3}}"], ["contact_details", "{\"google\":null,\"facebook\":\"https://facebook.com/someusername\",\"twitter\":null}"], ["updated_at", "2016-01-07 09:07:10.613237"], ["id", 2]]
   (0.2ms)  COMMIT
=> true

gem "has_json_attributes_on", "~> 0.0.3"

gem "has_json_attributes_on", github: "wiseallie/has_json_attributes_on"