Handle invalid parameters and missing bounced emails

app/assets/javascripts/admin/controllers/modals/admin-incoming-email.js.es6

@@ -2,6 +2,7 @@ import ModalFunctionality from 'discourse/mixins/modal-functionality';
 import IncomingEmail from 'admin/models/incoming-email';
 import computed from 'ember-addons/ember-computed-decorators';
 import { longDate } from 'discourse/lib/formatter';
+import { popupAjaxError } from 'discourse/lib/ajax-error';
 
 export default Ember.Controller.extend(ModalFunctionality, {
 
@@ -15,7 +16,12 @@ export default Ember.Controller.extend(ModalFunctionality, {
   },
 
   loadFromBounced(id) {
-    return IncomingEmail.findByBounced(id).then(result => this.set("model", result));
+    return IncomingEmail.findByBounced(id)
+                        .then(result => this.set("model", result))
+                        .catch(error => {
+                          this.send("closeModal");
+                          popupAjaxError(error);
+                        });
   }
 
 });

app/controllers/admin/email_controller.rb

@@ -91,13 +91,21 @@ class Admin::EmailController < Admin::AdminController
   def incoming_from_bounced
     params.require(:id)
 
-    bounced = EmailLog.find(params[:id].to_i)
+    begin
+      bounced = EmailLog.find_by(id: params[:id].to_i)
+      raise Discourse::InvalidParameters if bounced.nil?
+
       email_local_part, email_domain = SiteSetting.notification_email.split('@')
       bounced_to_address = "#{email_local_part}+verp-#{bounced.bounce_key}@#{email_domain}"
 
       incoming_email = IncomingEmail.find_by(to_addresses: bounced_to_address)
+      raise Discourse::NotFound if incoming_email.nil?
+
       serializer = IncomingEmailDetailsSerializer.new(incoming_email, root: false)
       render_json_dump(serializer)
+    rescue => e
+      render json: {errors: [e.message]}, status: 404
+    end
   end
 
   private