ukaz
v0.3.0
Published
Next-generation command line parser
Downloads
13
Maintainers
Readme
Next-generation command line parser for Node.js
Name
Pronounced /ǔːkaːz/ (oo-KAHZ)
Means "command" in Slovenian, or "decree" in Russian.
Get started
$ npm i ukaz
Usage
API is currently under development and is therefore unstable. Changes may be made at any time.
import * as ukaz from 'ukaz'
const app = new ukaz.Application('Hello world CLI app')
.helpFlag() // adds -h, --help
.validate() // ensures all required arguments are given before running handler
.arguments('[phrases...]')
.flag('-s|--shout', 'Shouts hello instead of being polite')
.option('-n, --name <name>', 'A name to say hello to instead of "world"', {
default: 'world'
})
.handler(async ({ flags, options, args }) => { // executed when the app runs
let name = options.name.value
if (flags.shout) {
console.log(`HELLO, ${name.toUpperCase()}!!!`)
} else {
console.log(`Hello, ${name}!`)
}
if (args.phrases.present) {
args.phrases.value.forEach(phrase => console.log(phrase))
}
})
app.run(process.argv)
.catch(error => { // catches any errors encountered during execution
if (error instanceof ukaz.CliParsingError) { // bad arguments or user input
console.error(`Error: ${error.message}`)
} else { // other application error
console.error(error)
}
})
Another CLI app framework? But we already have [other framework]!
There are some great toolkits out there already, such as commander.js and nash. But most CLI frameworks for Node.js are not currently taking advantage of Node's support for async
/await
which can make your CLI app more robust.
ukaz intends to correct that:
- All handlers are
async
functions. - Use
async
support to easily write synchronous or asynchronous code without unnecessary boilerplate. - All errors are safely bubbled up to your error-handling code when you call
app.run(...)
. Handle errors your way! - You terminate the process on your own terms. No surprise
process.exit(...)
calls. - Chain handlers together, much like middleware. Useful for larger, more involved applications.
Licence
MIT