Command-Line Interface

Learn About The Command-Line Interface

Explain what the command-line interface is. Identify the different shells for each operating system (OS).
  • Introduction
    • Developers commonly work in the command-line tool when coding projects such as Lightning Web Components
  • Command-Line Interface (CLI)
    • Graphic User Interfaces (GUIs) are interfaces that consist of screens, buttons, and menu(s), and make it easy to do basic tasks like navigation and database updates
    • Command Line Interface (CLI) is a text-based interface where you write commands in the tool
  • Command-Line Uses
    • CLI lets you do complex actions quickly, and is customizable with plug-ins and packages, which lets you customize your development workspace tools
    • CLI enables developers to execute scripts, create directories, and interact with tools like Git where you can build and work on source-driven development projects or CI integrations
  • Where Is the Command-Line Tool?
    • The OS you work on determines where the command-line tool is located:
      • macOS/Linux: primary command-line tool for macOS and Linux is Terminal
        • Open finder, type Terminal in the search field
      • Windows: primary command-line tool is Command Prompt
        • Click Start, type Command or cmd in the search field
    • Code editors like Visual Studio Code (VS Code) have built-in terminal windows
      • Salesforce recommends using VS Code terminal window to run commands and work with the Salesforce CLI
      • Salesforce Extensions in VS Code includes empowering shortcuts and tools for Salesforce development
  • What is a Shell?
    • Behind the command-line window is a command-line interpreter, or shell, that processes the commands you run
    • This page focuses on the default shells for macOS and Windows
  • Different Types of Shells
    • Windows: most common shell is PowerShell
    • macOS: most common shell is Zsh or z shell. Z shell is a unix shell that extends Bourne shell functionality (AKA BASH shell) with improvements
      • BASH stands for “bourne-again shell,” and follows the language and syntax called the Shell Command Language as defined by POSIX
      • BASH and Zsh are the most commonly used shells in developer tutorials
  • Know how PowerShell and ZSH Differ
    • Features and outputs of PowerShell and Zsh vary:
      • Zsh treats outputs as strings such as writing to .txt files
      • PowerShell treats the output as objects
    • String outputs generally make it easier for the user to transfer info across programs

Explore Command Structure and Navigation

Name the three main parts of a command structure. Identify the command used to change directories through the command line.
  • General Commands
    • General commands help you learn fundamental skills such as navigating in the command line and creating directories
  • Command Structure
    • All commands have three parts: $ command -flag arguments
    • $ sfdx force:project:create -n MyProject
      • Command: sfdx force:project:create,
        • AKA “utility,” tells the system what actions you want the tool to take
      • Flag: -n
        • AKA “options,” tells the command what other variables to include or describe what you want to name your project
        • Flags generally start with a -
        • Switches are like flags but don’t require arguments, identified by two hyphens, -- and followed by a value
        • Ex: --setdefault causes the system to remember your username and authentication
      • Argument: MyProject
        • Tell the system what variable you want to set or which process you want to invoke
        • Usually follow a flag after a space
        • Ex: -n MyProject
        • No spaces in an argument

  • Flags, Switches, and Arguments
    • Consider example of sfdx force:org:create -f project-scratch-def.json -s
      • Command: sfdx force:org:create tells the system we want to create a scratch org
      • Flags
        • -f is a required flag, tells the system to reference the filename that outlines what template to reference to create the scratch org
        • -s sets the newly created scratch org as the default. Does not require an argument because you can write the flag as a switch --setdefaultusername.
      • Arguments: the file’s name being referenced, project-scratch-def.json. It determines what features and special org set up is needed for the new scratch org.
  • How to Run Commands
    • To run a command, you type it into the command-line window and press enter
    • In macOS/Linux, a $ on the next line indicates success, or in Windows, a > on the next line indicates success
    • Keep in mind capitalization matters: myProject is not the same as MyProject
  • Navigation Commands
    • To see the current location in your directory, refer to the command-line path
      • macOS: yourname-ltm:~ yourname$
      • Windows: PS C:\Users\yourname>
    • cd Documents: change to the Documents directory
    • mkdir Resume: create a new directory named “Resume”
    • Navigate through multiple directories:
      • macOS: cd ~/Documents/Resume
      • Windows: cd ~\Documents\Resume
    • cd ..: navigate one level back
    • Print the working directory
      • macOS: pwd
      • Windows: cd
  • View Your Command-Line History
    • history: To see a history log of commands run so far
    • !503: re run the command executed on line 503

Learn About The Command-Line Tools

Identify the command-line tool that helps install packages using the command-line interface. Identify the software tool that is the successor to the IDE plug-in for Salesforce development.
  • Developer Command-Line Tools
    • Command-line tools, like npm and Salesforce CLI, give developers a boost in their projects by integrating with other developer tools
    • This section describes installation of:
      1. Visual Studio Code (VS Code)
      2. Node.js command line tool
      3. npm
      4. Salesforce CLI
  • Install Visual Studio Code
    • Visual Studio Code is Salesforce’s preferred code editor because its customizable and cross-platform
    • Visual Studio Salesforce Extension
      • Provides code completion, syntax highlighting, Apex debugging, etc
    • To install, in VS Code, select View, then Extensions, then search salesforce extension pack, then “Install”
  • Find Your Shell
    • In VS Code, click Terminal > New Terminal
      • For MacOS/Linux, you see Bash or Zsh
      • For Windows, you see PowerShell

  • Set Up Node.js and npm
    • If developing Lightning Web Components, or working in a JavaScript runtime environment such as Node.js, you’ll use npm to install and update packages
    • npm tool through the command-line interface helps install packages quickly and keeps them updated
    • First, install Node.js
    • Confirm installation by checking version with node -v
    • To see if you have npm installed, run npm -v
    • If you need to update npm version, run npm install npm@latest -g
  • Install and Update Salesforce CLI
  • Command-line tool that helps install packages using the command-line interface: npm
  • Software tool recommended to develop with for the Lightning Platform? Salesforce Extensions for VS Code