Return a more helpful server side validation message

[MegaphoneJon]

Overview

Presently, a FormBuilder form that fails server-side validation doesn't give a helpful message to the user. This makes it hard to fix their error.

Before

After

Comments

See also #25533.

[civibot]

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[mattwire]

@MegaphoneJon test fails related

[MegaphoneJon]

test this please

[eileenmcnaughton]

Test fails relate - tests look to need updating

Test Result (5 failures / +5)
api_v4_AfformAutocompleteUsageTest.testAutocompleteWithSavedSearchFilter
api_v4_AfformAutocompleteUsageTest.testCustomContactRefFieldWithGroupsFilter
api_v4_AfformAutocompleteUsageTest.testCustomContactRefFieldOnJoinEntity
api_v4_AfformContactUsageTest.testFormValidationEntityFields
api_v4_AfformContactUsageTest.testFormValidationEntityJoinFields

[mattwire]

jenkins test this please

[mattwire]

@MegaphoneJon Looks like tests need updating for the more specific validation messages.

[MegaphoneJon]

@eileenmcnaughton @mattwire I looked at this yesterday - and what I decided is that these errors need to be cleaned up in conjunction with this. "Illegal value for test_af_fields: contact_ref." is more helpful than "Validation Error" but I think it'd be far better to have a more user-friendly message.

[colemanw]

@MegaphoneJon is label cleanup something you'd like help with ?

[MegaphoneJon]

@MegaphoneJon is label cleanup something you'd like help with ?

I never volunteered to clean up the labels :) But if someone does, I'll update the affected tests to match the new labels.

I'll also say that we shouldn't get too hung up on this, because I think it'd be valuable to have more or less verbose messages based on a debug mode. Form builders and end users have different needs here.