Add SDG goal model

Since data for this model (title and description) is not generated in
CONSUL but by the United Nations, we aren't storing it in the database
but in our YAML translation files.

The reasoning is as follows. Suppose that, a few months after CONSUL
gets SDG support, a new language is added to CONSUL.

With YAML files, getting the texts in the new language would mean
updating CONSUL to include the new language.

But if we store these texts in the database, it means we have to update
the databases of all existing CONSUL installations, either each
installation by themselves (duplicating efforts) or running a rake task
(which we would have to write each time).

So we believe using translations works better in this case.

We're still storing records in the database with the code, so they can
be easily referenced via `has_many` or `has_many :through` associations.

app/models/sdg.rb

@@ -0,0 +1,5 @@
+module SDG
+  def self.table_name_prefix
+    "sdg_"
+  end
+end

app/models/sdg/goal.rb

@@ -0,0 +1,11 @@
+class SDG::Goal < ApplicationRecord
+  validates :code, presence: true, uniqueness: true
+
+  def title
+    I18n.t("sdg.goals.goal_#{code}.title")
+  end
+
+  def description
+    I18n.t("sdg.goals.goal_#{code}.description")
+  end
+end

config/initializers/inflections.rb

@@ -17,5 +17,6 @@
 
 ActiveSupport::Inflector.inflections(:en) do |inflect|
   inflect.plural(/^(\d+)$/i, '\1')
+  inflect.acronym "SDG"
   inflect.irregular "organización", "organizaciones"
 end

config/locales/en/sdg.yml

@@ -0,0 +1,6 @@
+en:
+  sdg:
+    goals:
+      goal_1:
+        title: "No Poverty"
+        description: "End poverty in all its forms, everywhere."

config/locales/es/sdg.yml

@@ -0,0 +1,6 @@
+es:
+  sdg:
+    goals:
+      goal_1:
+        title: "Fin de la pobreza"
+        description: "Poner fin a la pobreza en todas sus formas en todo el mundo."

db/migrate/20201111095452_create_sdg_goals.rb

@@ -0,0 +1,10 @@
+class CreateSDGGoals < ActiveRecord::Migration[5.2]
+  def change
+    create_table :sdg_goals do |t|
+      t.integer :code, null: false
+      t.timestamps
+
+      t.index :code, unique: true
+    end
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2020_09_08_084257) do
+ActiveRecord::Schema.define(version: 2020_11_11_095452) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "pg_trgm"
@@ -1297,6 +1297,13 @@ ActiveRecord::Schema.define(version: 2020_09_08_084257) do
     t.index ["process_type", "process_id"], name: "index_reports_on_process_type_and_process_id"
   end
 
+  create_table "sdg_goals", force: :cascade do |t|
+    t.integer "code", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["code"], name: "index_sdg_goals_on_code", unique: true
+  end
+
   create_table "settings", id: :serial, force: :cascade do |t|
     t.string "key"
     t.string "value"

spec/factories/sdg.rb

@@ -0,0 +1,5 @@
+FactoryBot.define do
+  factory :sdg_goal, class: "SDG::Goal" do
+    sequence(:code) { |n| n }
+  end
+end

spec/models/sdg/goal_spec.rb

@@ -0,0 +1,31 @@
+require "rails_helper"
+
+describe SDG::Goal do
+  it "is valid" do
+    expect(build(:sdg_goal)).to be_valid
+  end
+
+  it "is not valid without a code" do
+    expect(build(:sdg_goal, code: nil)).not_to be_valid
+  end
+
+  it "translates title" do
+    goal = SDG::Goal.where(code: "1").first_or_create!
+
+    expect(goal.title).to eq "No Poverty"
+
+    I18n.with_locale(:es) do
+      expect(goal.title).to eq "Fin de la pobreza"
+    end
+  end
+
+  it "translates description" do
+    goal = SDG::Goal.where(code: "1").first_or_create!
+
+    expect(goal.description).to eq "End poverty in all its forms, everywhere."
+
+    I18n.with_locale(:es) do
+      expect(goal.description).to eq "Poner fin a la pobreza en todas sus formas en todo el mundo."
+    end
+  end
+end