process.env

• process
  • global obj that provides information about, and control over, the current Node.js process.
  • As a global, it is always available to Node.js applications without using require().
• process.env
  • property returns an object containing the user environment.
  • It is possible to modify this object, but such modifications will not be reflected outside the Node.js process
  • is the object for the environment variables set in the OS, such as
    • >windows中的环境变量
      ALLUSERSPROFILE=C:\ProgramData
      CommonProgramFiles=C:\Program Files\Common Files
      CommonProgramFiles(x86)=C:\Program Files (x86)\Common Files
      CommonProgramW6432=C:\Program Files\Common Files
      ComSpec=C:\WINDOWS\system32\cmd.exe
      GRAILS_HOME=C:\Tools\grails-3.2.3
  • set the new env variable

    • process.env.mode = 'TESTING';
      

• why env?
  • One of the best ways to use sensitive information in open source repositories without hard-coding the information within publicly available repositories is setting environment variables.