Truncate error messages for failed Group Import

app/models/group_import_state.rb

@@ -3,6 +3,8 @@
 class GroupImportState < ApplicationRecord
   self.primary_key = :group_id
 
+  MAX_ERROR_LENGTH = 255
+
   belongs_to :group, inverse_of: :import_state
   belongs_to :user, optional: false
 
@@ -30,7 +32,7 @@ class GroupImportState < ApplicationRecord
     after_transition any => :failed do |state, transition|
       last_error = transition.args.first
 
-      state.update_column(:last_error, last_error) if last_error
+      state.update_column(:last_error, last_error.truncate(MAX_ERROR_LENGTH)) if last_error
     end
   end
 

changelogs/unreleased/georgekoltsov-truncate-last-error-group-import.yml

+---
+title: Fix failed group imports getting stuck by long error messages
+merge_request: 48989
+author:
+type: fixed

spec/models/group_import_state_spec.rb

@@ -70,4 +70,24 @@ RSpec.describe GroupImportState do
       end
     end
   end
+
+  context 'when import failed' do
+    context 'when error message is present' do
+      it 'truncates error message' do
+        group_import_state = build(:group_import_state, :started)
+        group_import_state.fail_op('e' * 300)
+
+        expect(group_import_state.last_error.length).to eq(255)
+      end
+    end
+
+    context 'when error message is missing' do
+      it 'has no error message' do
+        group_import_state = build(:group_import_state, :started)
+        group_import_state.fail_op
+
+        expect(group_import_state.last_error).to be_nil
+      end
+    end
+  end
 end