Create SessionDate model

This adds a model which will capture the dates for a particular session,
it's a one-to-many relationship with a unique constraint on the session
and date value.

This will eventually replace the single date column on sessions as the
latest designs have sessions across multiple dates.

app/models/session.rb

@@ -40,6 +40,7 @@ class Session < ApplicationRecord
   belongs_to :location, optional: true
 
   has_many :consent_forms
+  has_many :dates, class_name: "SessionDate"
   has_many :patient_sessions
 
   has_and_belongs_to_many :immunisation_imports

app/models/session_date.rb

@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+# == Schema Information
+#
+# Table name: session_dates
+#
+#  id         :bigint           not null, primary key
+#  value      :date             not null
+#  session_id :bigint           not null
+#
+# Indexes
+#
+#  index_session_dates_on_session_id            (session_id)
+#  index_session_dates_on_session_id_and_value  (session_id,value) UNIQUE
+#
+# Foreign Keys
+#
+#  fk_rails_...  (session_id => sessions.id)
+#
+class SessionDate < ApplicationRecord
+  audited
+
+  belongs_to :session
+
+  validates :value, uniqueness: { scope: :session }
+end

db/migrate/20240925075935_create_session_dates.rb

@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+class CreateSessionDates < ActiveRecord::Migration[7.2]
+  def change
+    # rubocop:disable Rails/CreateTableWithTimestamps
+    create_table :session_dates do |t|
+      t.references :session, foreign_key: true, null: false
+      t.date :value, null: false
+      t.index %i[session_id value], unique: true
+    end
+    # rubocop:enable Rails/CreateTableWithTimestamps
+  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[7.2].define(version: 2024_09_24_140304) do
+ActiveRecord::Schema[7.2].define(version: 2024_09_25_081048) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
 
@@ -461,6 +461,13 @@
     t.index ["vaccine_id", "programme_id"], name: "index_programmes_vaccines_on_vaccine_id_and_programme_id"
   end
 
+  create_table "session_dates", force: :cascade do |t|
+    t.bigint "session_id", null: false
+    t.date "value", null: false
+    t.index ["session_id", "value"], name: "index_session_dates_on_session_id_and_value", unique: true
+    t.index ["session_id"], name: "index_session_dates_on_session_id"
+  end
+
   create_table "sessions", force: :cascade do |t|
     t.date "date"
     t.bigint "location_id"
@@ -629,6 +636,7 @@
   add_foreign_key "programmes", "teams"
   add_foreign_key "programmes_sessions", "programmes"
   add_foreign_key "programmes_sessions", "sessions"
+  add_foreign_key "session_dates", "sessions"
   add_foreign_key "sessions", "teams"
   add_foreign_key "triage", "patient_sessions"
   add_foreign_key "triage", "programmes"

spec/factories/session_dates.rb

@@ -0,0 +1,25 @@
+# frozen_string_literal: true
+
+# == Schema Information
+#
+# Table name: session_dates
+#
+#  id         :bigint           not null, primary key
+#  value      :date             not null
+#  session_id :bigint           not null
+#
+# Indexes
+#
+#  index_session_dates_on_session_id            (session_id)
+#  index_session_dates_on_session_id_and_value  (session_id,value) UNIQUE
+#
+# Foreign Keys
+#
+#  fk_rails_...  (session_id => sessions.id)
+#
+FactoryBot.define do
+  factory :session_date do
+    session
+    value { Date.current }
+  end
+end

spec/models/session_date_spec.rb

@@ -0,0 +1,24 @@
+# frozen_string_literal: true
+
+# == Schema Information
+#
+# Table name: session_dates
+#
+#  id         :bigint           not null, primary key
+#  value      :date             not null
+#  session_id :bigint           not null
+#
+# Indexes
+#
+#  index_session_dates_on_session_id            (session_id)
+#  index_session_dates_on_session_id_and_value  (session_id,value) UNIQUE
+#
+# Foreign Keys
+#
+#  fk_rails_...  (session_id => sessions.id)
+#
+describe SessionDate do
+  subject(:session_date) { build(:session_date) }
+
+  it { should be_valid }
+end