Improve error messages

[artur-intech]

Real-world example of the problem:

Given

• DB column contacts.country_code (which contains postal address country code) has some value that has lost its validity over time (ISO 3166-1 alpha-2 may be deleted or reassigned)
• The rest of contact's attributes are valid

---

When

• I update that contact via EPP contact:update with valid data but don't specify postal address country code

Then

• As an EPP user I should get
  Postal address country code in our database in invalid. Please provide us valid data to proceed
  ("database" should be substituted with some abstract meaning)

---

When

• I update that contact via EPP contact:update with valid data and provide invalid postal address country code (say "RUSUS")

Then

• As an EPP user I should get
  Submitted postal address country code in invalid

---

Same principle should apply to any attribute of a domain or contact.

Open questions:

• Can we use same error message throughout the application (EPP, REST API, admin/registrar/registrant areas, rails c) or it's needed to decouple EPP and ActiveRecord messages.

---

Currently ActiveRecord messages are hard to read:

irb(main):003:0> c = Contact.new
irb(main):004:0> c.validate
irb(main):005:0> c.errors.full_messages
=> ["Name Required parameter missing - name", "Email Required parameter missing - email", "Email Email is invalid", "Email Email is invalid", "Phone Required parameter missing - phone", "Phone Phone nr is invalid"]

[teadur]

In what sitsuation would you get errors like that from contact in real life deployment, epp doesnot allow creating such object, only way to get such an object is from rails console.
Or i dont understand the problem correctly ?

[artur-intech]

epp doesnot allow creating such object

What "such"? Contact.new is one of the standard ways to create new contact in our application. The point of this ticket to review all error messages we show to the users (incl. users of our API). I am not sure if there should be some boundary between default ActiveRecord messages and EPP.

P.S. By API I mean the interface our objects provide, not REST API

[artur-intech]

@vohmar Ticket's objective needs your review