sade
Smooth (CLI) Operator 🎶
Sade is a small but powerful tool for building command-line interface (CLI) applications for Node.js that are fast, responsive, and helpful!
It enables default commands, git-like subcommands, option flags with aliases, default option values with type-casting, required-vs-optional argument handling, command validation, and automated help text generation!
Your app's UX will be as smooth as butter... just like Sade's voice. 😉
Install
$ npm install --save sade
Usage
Input:
#!/usr/bin/env node
const sade = require('sade');
const prog = sade('my-cli');
prog
.version('1.0.5')
.option('--global, -g', 'An example global flag')
.option('-c, --config', 'Provide path to custom config', 'foo.config.js');
prog
.command('build <src> <dest>')
.describe('Build the source directory. Expects an `index.js` entry file.')
.option('-o, --output', 'Change the name of the output file', 'bundle.js')
.example('build src build --global --config my-conf.js')
.example('build app public -o main.js')
.action((src, dest, opts) => {
console.log(`> building from ${src} to ${dest}`);
console.log('> these are extra opts', opts);
});
prog.parse(process.argv);
Output:
$ my-cli --help
Usage
$ my-cli <command> [options]
Available Commands
build Build the source directory.
For more info, run any command with the `--help` flag
$ my-cli build --help
Options
-v, --version Displays current version
-g, --global An example global flag
-c, --config Provide path to custom config (default foo.config.js)
-h, --help Displays this message
$ my-cli build --help
Description
Build the source directory.
Expects an `index.js` entry file.
Usage
$ my-cli build <src> [options]
Options
-o, --output Change the name of the output file (default bundle.js)
-g, --global An example global flag
-c, --config Provide path to custom config (default foo.config.js)
-h, --help Displays this message
Examples
$ my-cli build src build --global --config my-conf.js
$ my-cli build app public -o main.js
Tips
-
Define your global/program-wide version, options, description, and/or examples first.
Once you define a Command, you can't access the global-scope again.
-
Define all commands & options in the order that you want them to appear.
Sade will not mutate or sort your CLI for you. Global options print before local options.
-
Required arguments without values will error & exit
An Insufficient arguments!
error will be displayed along with a help prompt.
-
Don't worry about manually displaying help~!
Your help text is displayed automatically... including command-specific help text!
-
Automatic default/basic patterns
Usage text will always append [options]
& --help
and --version
are done for you.
-
Only define what you want to display!
Help text sections (example, options, etc) will only display if you provide values.
Subcommands
Subcommands are defined & parsed like any other command! When defining their usage
, everything up until the first argument ([foo]
or <foo>
) is interpreted as the command string.
They should be defined in the order that you want them to appear in your general --help
output.
Lastly, it is not necessary to define the subcommand's "base" as an additional command. However, if you choose to do so, it's recommended that you define it first for better visibility.
const prog = sade('git');
prog
.command('remote')
.describe('Manage set of tracked repositories')
.action(opts => {
console.log('~> Print current remotes...');
});
prog
.command('remote add <name> <url>', 'Demo...')
.action((name, url, opts) => {
console.log(`~> Adding a new remote (${name}) to ${url}`);
});
prog
.command('remote rename <old> <new>', 'Demo...')
.action((old, nxt, opts) => {
console.log(`~> Renaming from ${old} to ${nxt}~!`);
});
API
sade(name)
name
Type: String
Returns: Program
The name of your bin/program. Returns the Program
itself, wherein all other methods are available.
prog.command(usage, desc, opts)
Create a new Command for your Program. This changes the current state of your Program.
All configuration methods (prog.describe
, prog.action
, etc) will apply to this Command until another Command has been created!
usage
Type: String
The usage pattern for your current Command. This will be included in the general or command-specific --help
output.
Required arguments are wrapped with <
and >
characters; for example, <foo>
and <bar>
.
Optional arguments are wrapped with [
and ]
characters; for example, [foo]
and [bar]
.
All arguments are positionally important, which means they are passed to your current Command's handler
function in the order that they were defined.
When optional arguments are defined but don't receive a value, their positionally-equivalent function parameter will be undefined
.
Important: You must define & expect required arguments before optional arguments!
sade('foo')
.command('greet <adjective> <noun>')
.action((adjective, noun, opts) => {
console.log(`Hello, ${adjective} ${noun}!`);
})
.command('drive <vehicle> [color] [speed]')
.action((vehicle, color, speed, opts) => {
let arr = ['Driving my'];
arr.push(color ? `${color} ${vehicle}` : vehicle);
speed && arr.push(`at ${speed}`);
opts.yolo && arr.push('...YOLO!!');
let str = arr.join(' ');
console.log(str);
});
$ foo greet beautiful person
$ foo drive car
$ foo drive car red
$ foo drive car blue 100mph --yolo
desc
Type: String
Default: ''
The Command's description. The value is passed directly to prog.describe
.
opts
Type: Object
Default: {}
opts.default
Type: Boolean
Manually set/force the current Command to be the Program's default command. This ensures that the current Command will run if no command was specified.
Important: If you run your Program without a Command and without specifying a default command, your Program will exit with a No command specified
error.
const prog = sade('greet');
prog.command('hello');
prog.command('howdy', '', { default:true });
prog.describe(text)
Add a description to the current Command.
text
Type: String|Array
The description text for the current Command. This will be included in the general or command-specific --help
output.
Internally, your description will be separated into an Array
of sentences.
For general --help
output, only the first sentence will be displayed. However, all sentences will be printed for command-specific --help
text.
Note: Pass an Array
if you don't want internal assumptions. However, the first item is always displayed in general help, so it's recommended to keep it short.
prog.action(handler)
Attach a callback to the current Command.
handler
Type: Function
The function to run when the current Command is executed.
Its parameters are based (positionally) on your Command's usage
definition.
All options, flags, and extra/unknown values are included as the last parameter.
Note: Optional arguments are also passed as parameters & may be undefined
!
sade('foo')
.command('cp <src> <dest>')
.option('-f, --force', 'Overwrite without confirmation')
.option('-c, --clone-dir', 'Copy files to additional directory')
.option('-v, --verbose', 'Enable verbose output')
.action((src, dest, opts) => {
console.log(`Copying files from ${src} --> ${dest}`);
opts.c && console.log(`ALSO copying files from ${src} --> ${opts['clone-dir']}`);
console.log('My options:', opts);
})
prog.example(str)
Add an example for the current Command.
str
Type: String
The example string to add. This will be included in the general or command-specific --help
output.
Note: Your example's str
will be prefixed with your Programs's name
.
prog.option(flags, desc, value)
Add an Option to the current Command.
flags
Type: String
The Option's flags, which may optionally include an alias.
You may use a comma (,
) or a space (
) to separate the flags.
Note: The short & long flags can be declared in any order. However, the alias will always be displayed first.
Important: If using hyphenated flag names, they will be accessible as declared within your action()
handler!
prog.option('--global');
prog.option('-g, --global');
prog.option('--global -g');
desc
Type: String
The description for the Option.
value
Type: String
The default value for the Option.
Flags and aliases, if parsed, are true
by default. See mri
for more info.
Note: You probably only want to define a default value
if you're expecting a String
or Number
value type.
If you do pass a String
or Number
value type, your flag value will be casted to the same type. See mri#options.default
for info~!
prog.version(str)
The --version
and -v
flags will automatically output the Program version.
str
Type: String
Default: 0.0.0
The new version number for your Program.
Note: Your Program version
is 0.0.0
until you change it.
prog.parse(arr, opts)
Parse a set of CLI arguments.
arr
Type: Array
Your Program's process.argv
input.
Important: Do not .slice(2)
! Doing so will break parsing~!
opts
Type: Object
Default: {}
Additional process.argv
parsing config. See mri
's options for details.
Important: These values override any internal values!
prog
.command('hello')
.option('-f, --force', 'My flag');
prog.parse(process.argv, {
alias: {
f: ['foo', 'fizz']
},
default: {
abc: 123
}
});
opts.lazy
Type: Boolean
Default: false
If true, Sade will not immediately execute the action
handler. Instead, parse()
will return an object of { name, args, handler }
shape, wherein the name
is the command name, args
is all arguments that would be passed to the action handler, and handler
is the function itself.
From this, you may choose when to run the handler
function. You also have the option to further modify the args
for any reason, if needed.
let { name, args, handler } = prog.parse(process.argv, { lazy:true });
console.log('> Received command: ', name);
handler.apply(null, args);
prog.help(cmd)
Manually display the help text for a given command. If no command name is provided, the general/global help is printed.
Your general and command-specific help text is automatically attached to the --help
and -h
flags.
Note: You don't have to call this directly! It's automatically run when you bin --help
cmd
Type: String
Default: null
The name of the command for which to display help. Otherwise displays the general help.
License
MIT © Luke Edwards