link to submission preview page in completed emails

db/migrate/20231119222105_add_slug_to_submissions.rb

@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+class AddSlugToSubmissions < ActiveRecord::Migration[7.0]
+  class MigrationSubmission < ApplicationRecord
+    self.table_name = 'submissions'
+  end
+
+  def up
+    add_column :submissions, :slug, :string
+
+    MigrationSubmission.where(slug: nil).find_each do |submission|
+      submission.update_columns(slug: SecureRandom.base58(14))
+    end
+
+    change_column_null :submissions, :slug, false
+
+    add_index :submissions, :slug, unique: true
+  end
+
+  def down
+    remove_column :submissions, :slug
+  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[7.0].define(version: 2023_11_12_224432) do
+ActiveRecord::Schema[7.0].define(version: 2023_11_19_222105) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
 
@@ -124,7 +124,9 @@ ActiveRecord::Schema[7.0].define(version: 2023_11_12_224432) do
     t.text "template_submitters"
     t.text "source", null: false
     t.string "submitters_order", null: false
+    t.string "slug", null: false
     t.index ["created_by_user_id"], name: "index_submissions_on_created_by_user_id"
+    t.index ["slug"], name: "index_submissions_on_slug", unique: true
     t.index ["template_id"], name: "index_submissions_on_template_id"
   end