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SEARCH KEYWORD -- Error detection



  JS code to check different mobile devices

Today I come across a code snippet which uses JavaScript to check different mobile devices and then loads different CSS files accordingly. As we know that there are mobile devices with different screen sizes, it's always troublesome for web developers to develop cross browser and cross device compatible codes. Hope this one can help those who develop web apps on mobile devices. // Check whether it's a mobile device // wukong.name 20130716 if(/AppleWebKit.*Mobile/i.test(navigator.userAgent) || (...

   JavaScript,Mobile device,Detection     2013-11-28 05:25:10

  An experience on fixing HTTP 406 Not Acceptable error

This post is about an experience of mine on fixing a HTTP 406 Not Acceptable error seen on one of my page. Just got back from a business trip and opened my computer as usual to start to monitor my website statistics. But when I opened the page on showing real time page views, it shows nothing but zero. So I pressed F12 to bring up the developer tool to check on what's going on. The logic of loading the real time page view is backed by AJAX call. In the developer tool console, I see that the rAJA...

   PHP,AJAX,HTML,HTTP 406,CONTENT-TYPE     2019-03-30 04:09:10

  Capture video stream with WebRTC

WebRTC(Web Real-Time Communication) is an API supporting real time audio and video communication through a browser. It is now a recommended W3C standard. This post is to show you how to capture video stream and screenshot with WebRTC. Capture video stream To play video stream from the video camera, we first need to put a video tag in our code: <video id="video"></video> The main function to get the video stream is the navigator.getUserMedia, as of now only few of the browsers support...

   WebRTC,Video,Screenshot     2013-10-24 21:04:41

  Implementing DESede/ECB/NoPadding cipher algorithm in GoLang

By default, GoLang doesn't provide the ECB mode cipher for DESede though there is CBC mode provided. In cases we need to encrypt/decrypt data with ECB mode, we need to implement those by ourselves. This mode is frequently used when encrypting/decrypting PIN block which is small block data less than 16 bytes. In this post, we will introduce how to implement the DESede/ECB/NoPadding algorithm in GoLang by using the existing cipher support. Here we will not cover how DESede works in detail, instead...

   SECURITY,SAMPLE,GOLANG,DES,DESEDE,3DES     2019-07-29 06:43:50

  The evolving history of asynchronous operation in JavaScript

JavaScript is single threaded, it means there would be only one task running at any point of time. But this would slow down the overall program execution if there is long running task, hence asynchronous task execution is desired in complex cases. To achieve asynchronous task execution, there are a few options introduced in JavaScript. setTimeout/setInterval Event Promise Async/Await setTimeout/setInterval is one of the first mechanisms introduced in JavaScript to simulate asynchronous operati...

   JAVASCRIPT,ASYNC,PROMISE,AWAIT     2019-11-09 08:21:56

  A plugin to update last_error in Delayed Job

delayed_job is a process based asynchronous task processing gem which can be ran at background. It will fork the specified number of processes to execute the tasks asynchronously. The task status is usually stored in the database so that it can be easily integrated into a Rails application where asynchronous job execution is desired. Normally when a job fails to execute or error occurs, it would save the error into the database with the column last_error. Ideally all these will be handled b...

   RUBY,RUBY ON RAILS,DELAYED JOB,LAST_ERROR     2017-11-18 13:05:49

  No support of $.browser in jQuery 1.9

Starting from jQuery 1.9, $.browser is no longer supported to detect the nrpwser type and version. The substitute is $.support. In the newer jQuery 2.x versions, IE 6/7/8 are also not supported. If users want to support IE 6/7/8, they must use jQuery 1.9. If you want to fully support IE and want to use jQuery 1.9 and jQuery 2.0, the official solution is: <!--[if lt IE 9]> <script src='jquery-1.9.0.js'></script> <![endif]--> <!--[if gte IE 9]> <script src=...

   jQuery,$.browser,$.browser.version     2013-08-27 03:10:12

  Error handling style in C

Following are three error handling styles in C.Which one you like the most? Or you don't like any one?1. /* Problem : Not enough. Easy to be wrong */int foo(int bar){        int return_value = 0;        int doing_okay = 1;        doing_okay = do_something( bar );        if (doing_okay)        { ...

   C,Error handling style,Goto,Nested if     2012-04-24 06:51:00

  A String is not an Error

I decided to write a little article to discourage an unfortunately common pattern in Node.JS modules (and browser JavaScript, to a lesser extent) that can boil down to these two examples: // A:function myFunction () {  if (somethingWrong) {    throw 'This is my error'  }  return allGood;} and // B: async Node.JS-style callback with signature `fn(err, …)`function myFunction (callback) {  doSomethingAsync(function () {    // …    if (...

   JavaScript,Node.js,String,Error object     2011-12-23 08:00:32

  A strange behavior of printing struct with nested struct in GoLang

Normally when trying to print a struct , we would use %v to show all data of the struct. It will print the default format for each field in the struct. %v the value in a default format when printing structs, the plus flag (%+v) adds field names But recently we observed a strange behavior when printing a struct with nested struct which has a String() string implemented, the %v format prints an 'unexpected' output per our understanding.   Let's see the example snippet first. pa...

   PROGRAMMING,GOLANG     2018-10-29 09:59:49