PERF: Store `EmailLog#reply_key` as `uuid` data type.

app/models/email_log.rb

@@ -71,6 +71,10 @@ class EmailLog < ActiveRecord::Base
     super&.delete('-')
   end
 
+  def reply_key
+    super&.delete('-')
+  end
+
 end
 
 # == Schema Information
@@ -83,7 +87,7 @@ end
 #  user_id        :integer
 #  created_at     :datetime         not null
 #  updated_at     :datetime         not null
-#  reply_key      :string(32)
+#  reply_key      :uuid
 #  post_id        :integer
 #  topic_id       :integer
 #  skipped        :boolean          default(FALSE)

db/migrate/20180717084758_alter_reply_key_on_email_logs.rb

@@ -0,0 +1,9 @@
+class AlterReplyKeyOnEmailLogs < ActiveRecord::Migration[5.2]
+  def up
+    change_column :email_logs, :reply_key, 'uuid USING reply_key::uuid'
+  end
+
+  def down
+    change_column :email_logs, :reply_key, :string
+  end
+end

spec/models/email_log_spec.rb

@@ -101,19 +101,20 @@ describe EmailLog do
     end
   end
 
-  describe '#bounce_key' do
-    it 'should format the bounce key correctly' do
-      bounce_key = SecureRandom.hex
-      email_log = Fabricate(:email_log, user: user, bounce_key: bounce_key)
+  %w{reply_key bounce_key}.each do |key|
+    describe "##{key}" do
+      it "should format the #{key} correctly" do
+        hex = SecureRandom.hex
+        email_log = Fabricate(:email_log, user: user, "#{key}": hex)
 
-      raw_bounce_key = EmailLog.where(id: email_log.id)
-        .pluck("bounce_key::text")
-        .first
+        raw_key = EmailLog.where(id: email_log.id)
+          .pluck("#{key}::text")
+          .first
 
-      expect(raw_bounce_key).to_not eq(bounce_key)
-      expect(raw_bounce_key.delete('-')).to eq(bounce_key)
-      expect(EmailLog.find(email_log.id).bounce_key).to eq(bounce_key)
+        expect(raw_key).to_not eq(hex)
+        expect(raw_key.delete('-')).to eq(hex)
+        expect(EmailLog.find(email_log.id).send(key)).to eq(hex)
+      end
     end
   end
-
 end