SEARCH KEYWORD -- CONTAINER



  var in JavaScript

Geoff published an article sometime ago--"How one missing var ruined our launch". This article described one case where MelonCard uses Node.js as their backend system, suddenly there was a small registration peak period--50-100 people registered concurrently, then the entire website stopped responding and many other strange problems showed up. When they were investigating the source of the problem, they found one missing var in the following code.app.all(‘/apps/:user_id/status’, fun...

   JavaScript,Scope,variable     2012-05-26 12:35:36

  Products born for Cloud

Cloud computing has become increasingly popularity among companies. It greatly saves the investment of infrastructure and training with everything is running on cloud, it also improves the accessibility and flexibility of service provided by companies. With its popularity, many products are born or becoming popular to help build and move the apps to the cloud. Some well known names of these products are Vagrant, Docker/LXC, Chef and OpenStack. These tools can help create, test and deploy applica...

   Cloud,Openstack,Docker,Vargrant,LXC,Chef     2015-01-25 02:27:11

  What is pjax and why we should use it?

What is pjax? Now many websites such as Facebook, Twitter support one browsing style which is when you click one link on their sites, the page will not be redirected, instead only the page contents are updated and URL on address bar is changed. This kind of user experience is much better compared to load the whole page with a blink. There is one important component in the above browsing experience, these websites' AJAX refresh support browser history, when refreshing the page, the address on the...

   pjax,AJAX,history     2013-04-23 12:22:37

  How to let Google index AJAX contents?

There are lots of websites containing only one page now with the popularity of AJAX. The website will load different contents according to different inputs from users. This approach provides good user experience and it also helps save bandwidth, the drawback is that AJAX contents are not easy to be indexed by search engines. For example, if you have a website: http://example.com Users can see different contents with the appended # structure in the URL: http://example.com#1 http://example.com#2 h...

   AJAX,Search engine,Google,History     2013-07-16 00:47:14

  Push docker image to remote AWS ECR

With the popularity of distributed and large-scale systems, there are more and more adoptions of cloud services. One of the most popular container in the market is Docker and one of the most popular cloud service provider is AWS. From development perspective, there is frequent need to push local docker image to remote ECR for debugging or testing purpose. Normally when a code change is done and the committed change would go through a series of process like code review, push to remote repo, merge...

   CLOUD,AWS,DOCKER,AWS ECR     2020-12-13 04:12:26

  QScrollArea Scrollbar Display Solution

Qt framework is a popular C++ GUI framework developed by Nokia. And it is also cross platform compatible. Many developers are using Qt to develop C++ GUI programs. In Qt, some important components are deserved our close attention. Many developers faced the problem when they put some widgets in a QScrollArea widget and they want it to display scroll bars when the widgets inside the QScrollArea overflows. After many experiments, I propose a way which can show scroll bars as you expected. The...

   C++,Qt,GUI,QScrollBar,ScrollBar,Not display,Solution     2012-03-03 07:48:36

  A Python assignment trap

Python has no assignment, it only has reference. Assume, we have following code snippet: >>> values = [0, 1, 2] >>> values[1] = values >>> values [0, [...], 2] Why the result is not [0, [0, 1, 2], 2], instead it goes into an infinite loop? To understand this, we need to understand some basics about Python. Python has no variables, it only has labels. When we run: values = [0, 1, 2] Python will first create a list object [0,1,2], then it labels it as values. If we later...

   Python,Assignment,Trap,Shallow copy     2013-07-19 22:08:36

  Cloud Computing’s most Basic Concepts-Service Models

With the containerization of Docker, Kubernetes, CNCF, and the development of open-source communities, related frameworks and technology is booming and iterating rapidly. Cloud Computing, been applied for many years, is pushing developers into the new technological era. Companies and developers who are not using or not planning to use Cloud-Native gradually feel tremendous pressure in keeping up with the technology trends. The first step is to understand the concepts of IaaS, PaaS, FaaS, SaaS, S...

   CLOUD,PAAS,IAAS,CONCEPT     2021-01-24 05:23:11

  Check whether a remote server port is open on Linux

As a system administrator or network engineer or application developer, there is a need to check whether a port on remote server is open so that you can tell whether the service under check is running or not. In this post, we would cover a few methods to check whether a remote server port is open or not on Linux. telnet telnet is the most frequently used command on both Windows and Linux to check port. The simple usage for this command is  telnet [host] [port] When the port is open, the o...

   LINUX,TELNET,PORT,NC,NMAP     2017-12-23 11:45:20

  File upload in PHP

File is a special kind of form data, when being uploaded to the server through HTTP POST request, PHP will create a $_FILES global array, the relevant file information will be stored in this global array. We will illustrate file upload with some code snippets using PHP and look into the internal work mechanism. Lastly will talk about file upload security. File upload In order for users to upload files in client side, we have to provide a form on the user interface. Since the uploaded file is a s...

   File upload,PHP     2012-11-30 22:01:28