throttle js error reports to 1 per 5 secs.

and ignore more scribd errors

fixes #39274

Change-Id: Ie1ebcd4dd9e004f65d8fee68d97b2ffb377a5d22
Reviewed-on: https://gerrit.instructure.com/5820
Tested-by: Hudson <hudson@instructure.com>
Reviewed-by: Jon Jensen <jon@instructure.com>

Author: ryankshaw

public/javascripts/ajax_errors.js

@@ -19,8 +19,14 @@
 var iTest;
 INST.errorURL = '/record_js_error';
 INST.errorCount = 0;
+INST.errorLastHandledTimes = {};
 INST.log_error = function(params) {
   params = params || {};
+  var timestamp = +new Date();
+  // log errors with the same message once every 5 seconds at most.
+  // (so we don't fill the DOM with logging gifs)
+  if (INST.errorLastHandledTimes[params.message] > timestamp - 5000) return;
+  INST.errorLastHandledTimes[params.message] = timestamp;
   var username = "";
   try {
     username = $ && $.fn && $.fn.text && $("#identity .user_name").text();
@@ -48,7 +54,8 @@ INST.log_error = function(params) {
   document.body.appendChild(img);
 }
 window.onerror = function (msg, url, line) {
-  var ignoredErrors = ["webkitSafeEl"];
+  // these are errors that the actionScript in scrbd creates.
+  var ignoredErrors = ["webkitSafeEl", "NPMethod called on non-NPObject wrapped JSObject!"];
   for(var idx in ignoredErrors) {
     if(ignoredErrors[idx] && msg && msg.match && msg.match(ignoredErrors[idx])) {
       return true;
@@ -164,4 +171,4 @@ $(document).ready(function() {
   });
 
 });
-});
+});

spec/selenium/error_reports_sel.rb

@@ -0,0 +1,12 @@
+require File.expand_path(File.dirname(__FILE__) + '/common')
+
+describe "error reporting" do
+  it_should_behave_like "in-process server selenium tests"
+  it "should log the same error at most 1 time per 5 seconds" do
+    get('/logout')
+    4.times do
+      driver.execute_script("window.onerror('Throwing a test error', ''+document.location, 12)")
+    end
+    driver.execute_script("return $('body > img[src^=\"'+ INST.errorURL +'\"]').length").should == 1
+  end
+end