Add foreign key option to Fields (#807)

* Add foreign key option to assosiations Fields
* Add country code to customers in example_app to show how it works

docs/customizing_dashboards.md

@@ -83,6 +83,16 @@ which are specified through the `.with_options` class method:
 
 `:direction` - What direction the sort should be in, `:asc` (default) or `:desc`.
 
+`:primary_key` - Specifies object's primary_key. Defaults to `:id`.
+
+`:foreign_key` - Specifies the name of the foreign key directly. Defaults to `:#{attribute}_id`
+
+**Field::BelongsTo**
+
+`:primary_key` - Specifies object's primary_key. Defaults to `:id`.
+
+`:foreign_key` - Specifies the name of the foreign key directly. Defaults to `:#{attribute}_id`
+
 **Field::Number**
 
 `:decimals` - Set the number of decimals to display. Defaults to `0`.

lib/administrate/field/associative.rb

@@ -24,6 +24,10 @@ def associated_class_name
       def primary_key
         options.fetch(:primary_key, :id)
       end
+
+      def foreign_key
+        options.fetch(:foreign_key, :"#{attribute}_id")
+      end
     end
   end
 end

lib/administrate/field/belongs_to.rb

@@ -8,7 +8,7 @@ def self.permitted_attribute(attr)
       end
 
       def permitted_attribute
-        self.class.permitted_attribute(attribute)
+        foreign_key
       end
 
       def associated_resource_options

lib/administrate/field/deferred.rb

@@ -25,11 +25,11 @@ def searchable?
         options.fetch(:searchable, deferred_class.searchable?)
       end
 
-      delegate(
-        :html_class,
-        :permitted_attribute,
-        to: :deferred_class,
-      )
+      def permitted_attribute(attr)
+        options.fetch(:foreign_key, deferred_class.permitted_attribute(attr))
+      end
+
+      delegate :html_class, to: :deferred_class
     end
   end
 end

spec/example_app/app/dashboards/country_dashboard.rb

@@ -0,0 +1,20 @@
+require "administrate/base_dashboard"
+
+class CountryDashboard < Administrate::BaseDashboard
+  ATTRIBUTES = %i(code name).freeze
+
+  ATTRIBUTE_TYPES = {
+    created_at: Field::DateTime,
+    updated_at: Field::DateTime,
+    code: Field::String,
+    name: Field::String,
+  }.freeze
+
+  COLLECTION_ATTRIBUTES = ATTRIBUTES
+  FORM_ATTRIBUTES = ATTRIBUTES
+  SHOW_PAGE_ATTRIBUTES = ATTRIBUTES
+
+  def display_resource(resource)
+    resource.name
+  end
+end

spec/example_app/app/dashboards/customer_dashboard.rb

@@ -10,6 +10,8 @@ class CustomerDashboard < Administrate::BaseDashboard
     orders: Field::HasMany.with_options(limit: 2),
     updated_at: Field::DateTime,
     kind: Field::Select.with_options(collection: Customer::KINDS),
+    country: Field::BelongsTo.
+      with_options(primary_key: :code, foreign_key: :country_code),
   }
 
   COLLECTION_ATTRIBUTES = ATTRIBUTE_TYPES.keys
@@ -19,6 +21,7 @@ class CustomerDashboard < Administrate::BaseDashboard
     :email,
     :email_subscriber,
     :kind,
+    :country,
   ].freeze
 
   def display_resource(customer)

spec/example_app/app/models/country.rb

@@ -0,0 +1,3 @@
+class Country < ActiveRecord::Base
+  validates :code, :name, presence: true
+end

spec/example_app/app/models/customer.rb

@@ -1,5 +1,6 @@
 class Customer < ActiveRecord::Base
   has_many :orders, dependent: :destroy
+  belongs_to :country, foreign_key: :country_code, primary_key: :code
 
   validates :name, presence: true
   validates :email, presence: true

spec/example_app/db/migrate/20170510122301_create_countries.rb

@@ -0,0 +1,11 @@
+class CreateCountries < ActiveRecord::Migration[4.2]
+  def change
+    create_table :countries do |t|
+      t.string :code, null: false, index: { unique: true }
+      t.string :name
+
+      t.timestamps null: false
+    end
+    add_column :customers, :country_code, :string, index: true
+  end
+end

spec/example_app/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: 20170508183744) do
+ActiveRecord::Schema.define(version: 20170510122301) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -23,13 +23,23 @@
     t.datetime "updated_at", null: false
   end
 
-  create_table "customers", id: :serial, force: :cascade do |t|
-    t.string "name", null: false
-    t.string "email", null: false
+  create_table "countries", force: :cascade do |t|
+    t.string   "code",       null: false
+    t.string   "name"
     t.datetime "created_at", null: false
     t.datetime "updated_at", null: false
-    t.boolean "email_subscriber"
-    t.string "kind", default: "standard", null: false
+  end
+
+  add_index "countries", ["code"], name: "index_countries_on_code", unique: true, using: :btree
+
+  create_table "customers", force: :cascade do |t|
+    t.string   "name",                                  null: false
+    t.string   "email",                                 null: false
+    t.datetime "created_at",                            null: false
+    t.datetime "updated_at",                            null: false
+    t.boolean  "email_subscriber"
+    t.string   "kind",             default: "standard", null: false
+    t.string   "country_code"
   end
 
   create_table "delayed_jobs", id: :serial, force: :cascade do |t|

spec/example_app/db/seeds.rb

@@ -12,28 +12,40 @@
 Product.destroy_all
 ProductMetaTag.destroy_all
 Series.destroy_all
+Country.destroy_all
 
-100.times do
+countries = Country.create! [
+  { code: "US", name: "USA" },
+  { code: "CA", name: "Canada" },
+  { code: "CN", name: "China" },
+  { code: "RU", name: "Russia" },
+  { code: "AU", name: "Australia" },
+]
+
+customer_attributes = Array.new(100) do
   name = "#{Faker::Name.first_name} #{Faker::Name.last_name}"
-  Customer.create(
+  {
     name: name,
     email: Faker::Internet.safe_email(name),
-  )
+    country: countries.sample,
+  }
 end
 
+customers = Customer.create!(customer_attributes)
+
 product_attributes = YAML.load_file(Rails.root.join('db/seeds/products.yml'))
 
 product_attributes.each do |attributes|
   attributes = attributes.merge product_meta_tag_attributes: {
     meta_title: Faker::LordOfTheRings.character,
     meta_description: Faker::LordOfTheRings.location,
   }
-  Product.create attributes.merge(price: 20 + rand(50))
+  Product.create! attributes.merge(price: 20 + rand(50))
 end
 
-Customer.all.each do |customer|
+customers.each do |customer|
   (1..3).to_a.sample.times do
-    order = Order.create(
+    order = Order.create!(
       customer: customer,
       address_line_one: Faker::Address.street_address,
       address_line_two: Faker::Address.secondary_address,
@@ -44,7 +56,7 @@
 
     item_count = (1..3).to_a.sample
     Product.all.sample(item_count).each do |product|
-      LineItem.create(
+      LineItem.create!(
         order: order,
         product: product,
         unit_price: product.price,
@@ -54,4 +66,4 @@
   end
 end
 
-Series.create(name: "An example")
+Series.create!(name: "An example")

spec/lib/fields/belongs_to_spec.rb

@@ -25,8 +25,9 @@
         Foo = Class.new
         allow(Foo).to receive(:all).and_return([])
 
-        association = Administrate::Field::BelongsTo.
-          with_options(class_name: "Foo")
+        association = Administrate::Field::BelongsTo.with_options(
+          class_name: "Foo",
+        )
         field = association.new(:customers, [], :show)
         candidates = field.associated_resource_options
 
@@ -67,6 +68,17 @@
     end
   end
 
+  describe "foreign_key option" do
+    it "determines what foreign key is used on the relationship for the form" do
+      association = Administrate::Field::BelongsTo.with_options(
+        foreign_key: "foo_uuid", class_name: "Foo",
+      )
+      field = association.new(:customers, [], :show)
+      permitted_attribute = field.permitted_attribute
+      expect(permitted_attribute).to eq("foo_uuid")
+    end
+  end
+
   describe "#resources" do
     context "with `order` option" do
       it "returns the resources in correct order" do

spec/lib/fields/deferred_spec.rb

@@ -3,14 +3,25 @@
 
 describe Administrate::Field::Deferred do
   describe "#permitted_attribute" do
-    it "delegates to the backing class" do
-      deferred = Administrate::Field::Deferred.new(Administrate::Field::String)
-      allow(Administrate::Field::String).to receive(:permitted_attribute)
+    context "when given a `foreign_key` option" do
+      it "returns the value given" do
+        deferred = Administrate::Field::Deferred.
+          new(Administrate::Field::BelongsTo.with_options(foreign_key: :bar))
+        expect(deferred.permitted_attribute(:foo)).to eq(:bar)
+      end
+    end
 
-      deferred.permitted_attribute(:foo)
+    context "when not given a `foreign_key` option" do
+      it "delegates to the backing class" do
+        deferred = Administrate::Field::Deferred.
+          new(Administrate::Field::String)
+        allow(Administrate::Field::String).to receive(:permitted_attribute)
 
-      expect(Administrate::Field::String).
-        to have_received(:permitted_attribute).with(:foo)
+        deferred.permitted_attribute(:foo)
+
+        expect(Administrate::Field::String).
+          to have_received(:permitted_attribute).with(:foo)
+      end
     end
   end