SEARCH KEYWORD -- SYSTEM DESIGN


  Stub Mixlib::ShellOut and shell_out in Ruby unit testing

Unit testing is part of software development to ensure the tiny component of a function can work as designed. Different frameworks and tools can be used to run unit testing for different programming languages. In Ruby, one popular unit testing framework is Rspec, or Chefspec if you are writing Chef recipes. While writing Chef recipes, some low level commands(DOS commands or shell commands) need to be executed on the managed resource to perform actions or gather information. For example, lis...

   RUBY,UNIT TESTING,RSPEC,CHEFSPEC,SHELL_OUT     2016-11-11 00:14:46

  CASSANDRA data model

Cassandra is an open source distributed database, it combines dynamic key/value and column oriented feature of Bigtable. Features of Cassandra are: Flexible schema, no need to design schema first, it's very convenient to add or delete strings Support range search on keys High usability, extensible. The single node error will not affect the cluster. We can think Cassandra's data model as a 4 or 5 dimensional Hash. COLUMN Columns is the smallest data unit in Cassandra, it is a 3 dimensional data...

   Cassandra,database,sort     2013-06-08 22:07:40

  12 useful Chrome commands

Many useful features of Chrome don't show up on its menus. You can access them through the chrome:// command. In this article we will introduce 12 useful chrome:// commands. 1. chrome://flags It can be used to turn on or turn off some chrome features. 2. chrome://dns This command will show the domain name list caught by the browser. 3. chrome://downloads You can access this through chrome menu as well. The shortcut is Ctrl+J 4. chrome://extensions This command equals to Menu->Tools->Ext...

   Chrome,chrome://     2013-01-25 04:38:03

  Why Apple Mac switches its CPU? The war between Intel and ARM

About three months ago, the new iPad Pro was released and it supports touch pad and mouse. It conveys a clear message to users that they want people to treat iPad Pro as a laptop.  As we know, iPad and iPhone are both using iOS, if iOS can run on laptop,  it means MacOS and iOS can merge and become a unified OS. And if Mac and iPhone can share the same OS, it means the same app can run in all places. It is becoming clearer and clearer that Apple is planning to do this exact thing. Late...

   APPLE,INTEL,ARM,WWDC,A14     2020-06-20 00:19:02

  Load and execute JavaScript

When we load and execute JavaScript in a webpage, there are many points we need to care about because of its design and feature. There are two features about JavaScript execution in a browser: 1). The JavaScript codes will be executed immediately once loaded;2). When JavaScript codes are being executed, they will block the following contents (including page rendering and other resources downloading). So if there are multiple js files to be loaded, these codes will be executed sequentially. Since...

   JavaScript,async,defer,load,execute     2013-06-07 04:53:46

  Steve Jobs's prediction about wireless,iPad and App Store in 1983

1983 was still a year uncultivated. That year, Apple released the first personal computer Apple Lisa with graphical user interface in the world, TCP/IP was released less than two years, the Internet was basically still a wasteland. General people had few knowledge about computer. Steve Jobs still needed to start with "What is the computer" in his speech. Today, we have become accustomed to social networking, smart phones and mobile Internet, it was really unbelievable at that time. That ye...

   Steve Jobs, record,Apple,prediction     2012-10-03 04:37:17

  Tips to Keep in Mind When Adding Devices to WiFi

When it comes to powerful tools, it is hard to beat the Internet. We can use it to access a huge variety of news, information, entertainment, products and more. When the Internet first became a thing, people pretty much had to be sitting at their computers to use it. But now, thanks to the advent of a wireless network known as WiFi, you can connect to the Internet through your smartphones, streaming devices, laptops and more from anywhere in the house. If you are in the market for some new tech...

   ROUTER,TIPS,WIFI     2021-10-01 08:19:19

  The Risks of Prioritizing Features Over Security in China's EV Industry

In recent years, China's electric vehicle (EV) industry has seen a surge in innovation and growth. Companies like BYD, NIO, XPeng, and Xiaomi have become household names, not just in China but globally. These companies have been at the forefront of integrating cutting-edge technology into their vehicles, often promoting new features such as autonomous driving, advanced infotainment systems, and seamless connectivity. However, this rapid pace of innovation has raised concerns about whether these...

   SECURITY,CHINA,EV CAR     2024-11-20 01:14:18

  Expectations, Desperation And Anticipation All You Need To Know About iOS 9.3

With so much anticipation filled among the audience, iOS 9.3 on contrary came out to be as a blooper. All the users were filled with a lot of enthusiasm about the latest advancements in the software, but the final release went to several crest and troughs. iOS 9.3 was quite important for the users when it comes to mobile OS update, however this did not go as it was expected to be for the iOS. The latest software in some cases is locking users. Along with the users this has also creased the eye ...

   IPHONE APP DEVELOPMENT,IPHONE APP DEVELOPER,IOS DEVELOPER,IOS APP DEVELOPMENT,IPHONE APP DEVELOPERS     2016-04-11 03:05:15

  HeartBleed: Inside the heart, what happens to a normal WEB user?

To be brief, our email, IM, facebook etc. are at the risk, so try to minimize the access in these few days. Especially we should try to avoid log into our internet-banking, because we may expose our user id and password. Also later when the service providers fix the bug, we would better to change a new password for all the web accounts that are important to us. Here comes the technical explanation. You might notice before that a lot of websites use URL starting with "https". For example, https:/...

   HeartBleed,Analysis     2014-04-09 22:41:43

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