plainterm.js

A dead simple lightweight pure Javascript terminal "emulator" that mimics terminal behaviour in browser.

Features:

• Tiny, pure JS, works in ES6+
• Easy-to-add custom commands
• Events
• Command history
• Command arguments existence validation
• "Foreground processes" imitation
• API

Usage

Download the latest compiled JS and CSS release or install with Bower:

bower install plainterm.js

Include the js in your page:

<script src="./plainterm.js"></script>

Initialize with parameters:

var settings = {
    id: "terminal", 
    welcome: "Welcome to plainterm.js terminal emulator", 
    prompt: "user@mkrl.xyz:~$",
    commands: {
        echo: {
            name: "echo", 
            description: "a test command with one echo arg", 
            parameters: ["a string to be echoed in console"],
            func: function(params){plainterm.print(params[0])} 
        },
        test: {
            name: "test", 
            description: "a test command with no args", 
            func: function(){plainterm.print("testing things")} 
        },
        multiply: {
            name: "multiply",
            description: "Multiply two numbers",
            parameters: ["number one", "number two"],
            func: function(params){plainterm.print(params[0]*params[1])}
        }
    }
};

plainterm.init(settings);

Working with the terminal

help - Display a list of all commands with descriptions

command - Execute a command. Will display "Usage: command [parameter 1 description] [parameter 2 description], etc.", when it requires arguments but is called without them.

API

plainterm object

Method	Description	Parameters
init(settings)	Initialize a terminal in a DOM with given ID	settings object.
print(text, c)	Prints a given text in the terminal (accepts raw HTML)	text - String, c - Boolean, optional, defaults to false. Count given string as a command (displays prompt, syntax highlight and appears in history)
run(text)	Emulates a command execution in a terminal (acts the same way as a user would have typed and pressed Enter)	text - String
hist(up)	Search in command history. Returns string.	up - Boolean, optional. Defaults to true. Upward/downward search.
start()	Starts a "foreground process": user input is blocked and command prompt never appears.
stop()	Stops "foreground process".
type(text, speed, command)	Prints a text with "typing" effect. Hides and blocks user input while typing.	text - String, text to be printed. speed - integer, miliseconds. The higher the number, the slower. command - boolean, prepend/hide command line prompt.

settings object

Parameter	Description	Default
id: string	A DOM id to initialize terminal in.	'terminal'
welcome: string	A welcome message that is being printed on initialization	'plainterm.js v. [version]'
help: boolean	Toggle default help command that lists all the available commands and their descriptions.	true
prompt: string	Terminal prompt	'$ '
commands: object	commands object

commands object

Parameter	Description
name: string	Command name.
description: string	Command description, used for the default help command.
parameters: string array	Array of strings that desribe command line arguments in order of appearance.
func: function(params)	Function. Accepts an array of parameters in order of appearance (params[0] for the first argument, etc.)

Events

Event	Description
onInit	Terminal initialization
onCommand	Existing command executed
onCommand404	Non-existing command executed
onProcessStart	Process started
onProcessStop	Process stopped