## Rails Settings Cached
This a plugin that makes managing a table of
а global key, value pairs easy. Think of it like a global Hash stored in your database,
that uses simple ActiveRecord like methods for manipulation. Keep track of any global
setting that you don't want to hard code into your rails app. You can store any kind
of object. Strings, numbers, arrays, or any object.
> 🚨 BREAK CHANGES WARNING:
> rails-settings-cached 2.x has redesigned the API, the new version will compatible with the stored setting values by an older version.
> When you want to upgrade 2.x, you must read the README again, and follow guides to change your Setting model.
> 0.x stable branch: https://github.com/huacnlee/rails-settings-cached/tree/0.x
## Status
[](https://rubygems.org/gems/rails-settings-cached) [](http://travis-ci.org/huacnlee/rails-settings-cached) [](https://codeclimate.com/github/huacnlee/rails-settings-cached) [](https://codecov.io/github/huacnlee/rails-settings-cached?branch=master)
## Setup
Edit your Gemfile:
```ruby
gem "rails-settings-cached", "~> 2.0"
```
Generate your settings:
```bash
$ rails g settings:install
```
If you want custom model name:
```bash
$ rails g settings:install
```
Or use a custom name:
```bash
$ rails g settings:install SiteConfig
```
You will get `app/models/setting.rb`
```rb
class Setting < RailsSettings::Base
# cache_prefix { "v1" }
field :host, default: "http://example.com"
field :readonly_item, type: :integer, default: 100, readonly: true
field :user_limits, type: :integer, default: 20
field :admin_emails, type: :array, default: %w[admin@rubyonrails.org]
field :captcha_enable, type: :boolean, default: 1
field :notification_options, type: :hash, default: {
send_all: true,
logging: true,
sender_email: "foo@bar.com"
}
end
```
You must use `field` method to statement the setting keys, otherwise you can't use it.
Now just put that migration in the database with:
```bash
rake db:migrate
```
## Usage
The syntax is easy. First, let's create some settings to keep track of:
```ruby
irb > Setting.host
"http://example.com"
irb > Setting.host = "https://your-host.com"
irb > Setting.host
"https://your-host.com"
irb > Setting.user_limits
20
irb > Setting.user_limits = "30"
irb > Setting.user_limits
30
irb > Setting.user_limits = 45
irb > Setting.user_limits
45
irb > Setting.captcha_enable
1
irb > Setting.captcha_enable?
true
irb > Setting.captcha_enable = "0"
irb > Setting.captcha_enable
false
irb > Setting.captcha_enable = "1"
irb > Setting.captcha_enable
true
irb > Setting.captcha_enable = "false"
irb > Setting.captcha_enable
false
irb > Setting.captcha_enable = "true"
irb > Setting.captcha_enable
true
irb > Setting.captcha_enable?
true
irb > Setting.admin_emails
["admin@rubyonrails.org"]
irb > Setting.admin_emails = %w[foo@bar.com bar@dar.com]
irb > Setting.admin_emails
["foo@bar.com", "bar@dar.com"]
irb > Setting.admin_emails = "huacnlee@gmail.com,admin@admin.com\nadmin@rubyonrails.org"
irb > Setting.admin_emails
["huacnlee@gmail.com", "admin@admin.com", "admin@rubyonrails.org"]
irb > Setting.notification_options
{
send_all: true,
logging: true,
sender_email: "foo@bar.com"
}
irb > Setting.notification_options = {
sender_email: "notice@rubyonrails.org"
}
irb > Setting.notification_options
{
sender_email: "notice@rubyonrails.org"
}
```
## Readonly field
Sometimes you may need to use Setting before Rails is initialized, for example `config/devise.rb`
```rb
Devise.setup do |config|
if Setting.omniauth_google_client_id.present?
config.omniauth :google_oauth2, Setting.omniauth_google_client_id, Setting.omniauth_google_client_secret
end
end
```
In this case, you must define the `readonly` field:
```rb
class Setting < RailsSettings::Base
# cache_prefix { "v1" }
field :omniauth_google_client_id, default: ENV["OMNIAUTH_GOOGLE_CLIENT_ID"], readonly: true
field :omniauth_google_client_secret, default: ENV["OMNIAUTH_GOOGLE_CLIENT_SECRET"], readonly: true
end
```
### Caching flow:
```
Setting.host -> Check Cache -> Exist - Get value of key for cache -> Return
|
Fetch all key and values from DB -> Write Cache -> Get value of key for cache -> return
|
Return default value or nil
```
In each Setting keys call, we will load the cache/db and save in `Thread.current` to avoid hit cache/db.
Each key update will expire the cache, so do not add some frequent update key.
## Change cache key
Some times you may need to force update cache, now you can use `cache_prefix`
```ruby
class Setting < RailsSettings::Base
cache_prefix { "you-prefix" }
...
end
```
In testing, you need add `Setting.clear_cache` for each Test case:
```rb
class ActiveSupport::TestCase
teardown do
Setting.clear_cache
end
end
```
-----
## How to manage Settings in the admin interface?
If you want to create an admin interface to editing the Settings, you can try methods in following:
config/routes.rb
```rb
namespace :admin do
resources :settings
end
```
app/controllers/admin/settings_controller.rb
```rb
module Admin
class SettingsController < ApplicationController
before_action :get_setting, only: [:edit, :update]
def show
end
def create
setting_params.keys.each do |key|
next if key.to_s == "site_logo"
Setting.send("#{key}=", setting_params[key].strip) unless setting_params[key].nil?
end
redirect_to admin_settings_path(notice: "Setting was successfully updated.")
end
private
def setting_params
params.require(:setting).permit(:host, :user_limits, :admin_emails,
:captcha_enable, :notification_options)
end
end
end
```
app/views/admin/settings/show.html.erb
```erb
<%= form_for(Setting.new, url: admin_settings_path) do |f| %>
Use YAML format to config the SMTP_html
<% end %>
```
## Backward compatible to support 0.x scoped settings
You may used the scoped setting feature in 0.x version. Before you upgrade rails-settings-cached 2.x, you must follow this guide to backward compatible it.
For example:
```rb
class User < ApplicationRecord
include RailsSettings::Extend
end
@user.settings.color = "red"
@user.settings.foo = 123
```
create `app/models/concerns/scoped_setting.rb`
```rb
module ScopedSetting
extend ActiveSupport::Concern
included do
has_many :settings, as: :thing
end
class_methods do
def scoped_field(name, default: nil)
define_method(name) do
obj = settings.where(var: name).take || settings.new(var: name, value: default)
obj.value
end
define_method("#{name}=") do |val|
record = settings.where(var: name).take || settings.new(var: name)
record.value = val
record.save!
val
end
end
end
end
```
Now include it for your model:
```rb
class User < ApplicationRecord
include ScopedSetting
scoped_field :color, default: ""
scoped_field :foo, default: 0
end
```
Now you must to find project with ".setting." for replace with:
Same values will fetch from the `settings` table.
```rb
@user.color = "red"
@user.color # => "red"
@user.foo = 123
@user.foo # =>
```
## Use cases:
- [ruby-china/ruby-china](https://github.com/ruby-china/ruby-china)
- [thebluedoc/bluedoc](https://github.com/thebluedoc/bluedoc/blob/master/app/models/setting.rb)
- [tootsuite/mastodon](https://github.com/tootsuite/mastodon)
- [helpyio/helpy](https://github.com/helpyio/helpy)