[CST] Use json_schemer in SavedClaim (#19684)

* Use json schemer in savedclaim

* Adds actual feature flipper, fixes already-existing tests

* Fixes more existing tests

* Fixes rubocop

* Play more nicely with error array

* More elegant error handling

* Rubocop

* Error handling redux redux

* Stub, rather than actually disable, the feature flipper

* Json schemer can detect fake emails

* Fixes some more specs. Getting there.

* rubocop

* Fixing some more specs, adding some stubs, learning

* See if tests pass with old flipper syntax

* Fixes more specs

* More passing specs. This might be all of them?

* Rubocop

* Adds some affirmative tests with the JSON Schemer flipper enabled

* Rubocop

* Adds comments to json validation methods for clarity on the gem switch

* Finishes adding affirmative (flipper on) tests. Uses true/false each block.

* Standardize error object to use symbols for keys

* Rubocop

* Fixes last spec, hopefully

* Rubocop

app/models/saved_claim.rb

@@ -99,6 +99,8 @@ def form_matches_schema
     unless validation_errors.empty?
       Rails.logger.error('SavedClaim form did not pass validation', { guid:, errors: validation_errors })
     end
+
+    schema_errors.empty? && validation_errors.empty?
   end
 
   def to_pdf(file_name = nil)
@@ -147,14 +149,57 @@ def va_notification?(email_template_id)
 
   private
 
+  # Depending on the feature flipper, validate the *entire schema*
+  # via either the json_schema or json_schemer gem.
+  # This is tied to vets-api #19684
   def validate_schema(schema)
+    if Flipper.enabled?(:validate_saved_claims_with_json_schemer)
+      validate_schema_with_json_schemer(schema)
+    else
+      validate_schema_with_json_schema(schema)
+    end
+  end
+
+  # Depending on the feature flipper, validate the *parsed form*
+  # via either the json_schema or the json_schemer gem.
+  # This is tied to vets-api #19684
+  def validate_form(schema, clear_cache)
+    if Flipper.enabled?(:validate_saved_claims_with_json_schemer)
+      validate_form_with_json_schemer(schema)
+    else
+      validate_form_with_json_schema(schema, clear_cache)
+    end
+  end
+
+  # For json_schemer, the default behavior is not to raise an exception
+  # on validation, so we return an array of errors if they exist.
+  # This method validates the *entire schema*.
+  def validate_schema_with_json_schemer(schema)
+    errors = JSONSchemer.validate_schema(schema).to_a
+    return [] if errors.empty?
+
+    reformatted_schemer_errors(errors)
+  end
+
+  # For json_schema, validation errors raise an exception.
+  # This method validates the *entire schema*.
+  def validate_schema_with_json_schema(schema)
     JSON::Validator.fully_validate_schema(schema, { errors_as_objects: true })
   rescue => e
     Rails.logger.error('Error during schema validation!', { error: e.message, backtrace: e.backtrace, schema: })
     raise
   end
 
-  def validate_form(schema, clear_cache)
+  # This method validates the *parsed form* with json_schemer.
+  def validate_form_with_json_schemer(schema)
+    errors = JSONSchemer.schema(schema).validate(parsed_form).to_a
+    return [] if errors.empty?
+
+    reformatted_schemer_errors(errors)
+  end
+
+  # This method validates the *parsed form* with json_schema.
+  def validate_form_with_json_schema(schema, clear_cache)
     JSON::Validator.fully_validate(schema, parsed_form, { errors_as_objects: true, clear_cache: })
   rescue => e
     PersonalInformationLog.create(data: { schema:, parsed_form:, params: { errors_as_objects: true, clear_cache: } },
@@ -164,6 +209,18 @@ def validate_form(schema, clear_cache)
     raise
   end
 
+  # This method exists to change the json_schemer errors
+  # to be formatted like json_schema errors, which keeps
+  # the error logging smooth and identical for both options.
+  def reformatted_schemer_errors(errors)
+    errors.map!(&:symbolize_keys)
+    errors.each do |error|
+      error[:fragment] = error[:data_pointer]
+      error[:message] = error[:error]
+    end
+    errors
+  end
+
   def attachment_keys
     []
   end

config/features.yml

@@ -1537,6 +1537,10 @@ features:
     actor_type: user
     description: When enabled, the VAProfile::V3::ContactInformation will be enabled
     enable_in_development: true
+  validate_saved_claims_with_json_schemer:
+    actor_type: user
+    description: When enabled, Saved Claims will be validated using the JSON Schemer gem rather than JSON Schema
+    enable_in_development: false
   veteran_onboarding_beta_flow:
     actor_type: user
     description: Conditionally display the new veteran onboarding flow to user

modules/pensions/spec/models/pensions/saved_claim_spec.rb

@@ -49,18 +49,45 @@
       )
     end
 
-    describe '#process_attachments!' do
-      it 'sets the attachments saved_claim_id' do
-        expect(Lighthouse::SubmitBenefitsIntakeClaim).not_to receive(:perform_async).with(claim.id)
-        claim.process_attachments!
-        expect(claim.persistent_attachments.size).to eq(2)
+    context 'using JSON Schema' do
+      before do
+        allow(Flipper).to receive(:enabled?).with(:validate_saved_claims_with_json_schemer).and_return(false)
+      end
+
+      describe '#process_attachments!' do
+        it 'sets the attachments saved_claim_id' do
+          expect(Lighthouse::SubmitBenefitsIntakeClaim).not_to receive(:perform_async).with(claim.id)
+          claim.process_attachments!
+          expect(claim.persistent_attachments.size).to eq(2)
+        end
+      end
+
+      describe '#destroy' do
+        it 'also destroys the persistent_attachments' do
+          claim.process_attachments!
+          expect { claim.destroy }.to change(PersistentAttachment, :count).by(-2)
+        end
       end
     end
 
-    describe '#destroy' do
-      it 'also destroys the persistent_attachments' do
-        claim.process_attachments!
-        expect { claim.destroy }.to change(PersistentAttachment, :count).by(-2)
+    context 'using JSON Schemer' do
+      before do
+        allow(Flipper).to receive(:enabled?).with(:validate_saved_claims_with_json_schemer).and_return(true)
+      end
+
+      describe '#process_attachments!' do
+        it 'sets the attachments saved_claim_id' do
+          expect(Lighthouse::SubmitBenefitsIntakeClaim).not_to receive(:perform_async).with(claim.id)
+          claim.process_attachments!
+          expect(claim.persistent_attachments.size).to eq(2)
+        end
+      end
+
+      describe '#destroy' do
+        it 'also destroys the persistent_attachments' do
+          claim.process_attachments!
+          expect { claim.destroy }.to change(PersistentAttachment, :count).by(-2)
+        end
       end
     end
   end

spec/factories/gids_response.rb

@@ -16,11 +16,11 @@
             versioned_school_certifying_officials: [
               {
                 priority: 'Primary',
-                email: 'test@edu_sample.com'
+                email: 'user@school.edu'
               },
               {
                 priority: 'Secondary',
-                email: 'test@edu_sample.com'
+                email: 'user@school.edu'
               }
             ]
           }

spec/factories/va10203.rb

@@ -18,7 +18,7 @@
         schoolCity: 'Test',
         schoolState: 'TN',
         schoolCountry: 'USA',
-        schoolEmailAddress: 'test@edu_sample.com',
+        schoolEmailAddress: 'user@school.edu',
         schoolStudentId: '01010101',
         isActiveDuty: true,
         veteranAddress: {
@@ -58,7 +58,7 @@
         schoolCity: 'Test 2',
         schoolState: 'SC',
         schoolCountry: 'USA',
-        schoolEmailAddress: 'test@edu_sample.com',
+        schoolEmailAddress: 'user@school.edu',
         schoolStudentId: '01010101',
         isActiveDuty: true,
         veteranAddress: {
@@ -98,7 +98,7 @@
         schoolCity: 'Test 2',
         schoolState: 'SC',
         schoolCountry: 'USA',
-        schoolEmailAddress: 'test@edu_sample.com',
+        schoolEmailAddress: 'user@school.edu',
         schoolStudentId: '01010101',
         isActiveDuty: true,
         veteranAddress: {