Add json response exceptions_app

app/controllers/errors_controller.rb

@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+class ErrorsController < ApplicationController
+  def show
+    exception = request.env['action_dispatch.exception']
+    status_code = ActionDispatch::ExceptionWrapper.new(request.env, exception).status_code
+    request_id = request.env['action_dispatch.request_id']
+    render json: { error: ErrorCodes::INTERNAL_SERVER_ERROR, request_id: request_id }, status: status_code
+  end
+end

config/environments/production.rb

@@ -98,4 +98,9 @@
 
   # Do not dump schema after migrations.
   config.active_record.dump_schema_after_migration = false
+
+  # Returns json on error
+  config.exceptions_app = ->(env) {
+    ErrorsController.action(:show).call(env)
+  }
 end

lib/error_codes.rb

@@ -5,6 +5,7 @@ module ErrorCodes
   INVALID_TOKEN = -1
   EXPIRED_TOKEN = -2
   MISSING_AUTHENTICATION = -3
+  INTERNAL_SERVER_ERROR = -4
 
   # Competition Errors
   COMPETITION_NOT_FOUND = -1000