clidec

this software is very much a WIP.

What?

A tiny framework for building CLI tools/application using decorators and TypeScript.

Built on command-line-args and command-line-usage.

Inspired by NestJS and Angular.

Why?

• You like writing CLI tools, but you hate the tedious overhead of having to set up sub-commands & options/flags, plus supporting decent help menus.
• You think CLI tools like Helm and git are pretty good examples of how CLI tools should work.
• Meta-programming is cool in 2019
• If you call yourself a JS dev and you're not writng frameworks what are you doing with your life?

Ok, show me?

Given the following file test.ts:

import { bootstrap, Command, Help, Opt } from "clidec";

@Help([
  {
    header: "Test - test command",
    content:
      "This command shows how clidec works, and how it can be used to bootstrap cli app development really quickly & with minimal boilerplate." +
      "FYI, this help block uses {green.bold chalk} template syntax."
  },
  {
    header: "Examples",
    content: ["$ test foo [file]", "$ test bar"]
  }
])
class Test {
  @Command({
    name: "foo",
    alias: "f",
    summary: "this foo command does foo stuff",
    help: [
      {
        header: "foo command",
        content:
          "This command uses a bunch of different options, including required options."
      },
      {
        header: "examples",
        content: ["$ cmd foo <file>", "$ cmd foo -r <file>"]
      }
    ]
  })
  public foo(
    @Opt({
      name: "file",
      alias: "f",
      defaultOption: true,
      required: true,
      typeLabel: "file",
      description: "file to read"
    })
    file?: string,
    @Opt({
      name: "raw",
      alias: "r",
      type: Boolean,
      description: "use raw input, for example"
    })
    raw?: boolean
  ): void {
    // do some command stuff
  }

  @Command({
    name: "bar",
    alias: "b",
    summary: "the bar command does bar things",
    help: [
      {
        header: "bar command",
        content:
          "This command has an option that can be used multiple times. The value that's passed to the function will be a string array."
      },
      {
        header: "examples:",
        content: ["$ test bar -m first -m second"]
      }
    ]
  })
  public bar(
    @Opt({
      multiple: true,
      name: "multiple",
      alias: "m",
      description: "argument that can be used multiple times",
      typeLabel: "string"
    })
    multiple: string[]
  ) {
    // do some stuff here
  }
}

// actually run our commands!
bootstrap(new Test());

Example output from running $ ts-node test.ts / $ ts-node test.ts help / $ ts-node test.ts --help:

Test - test command

  This command shows how clidec works, and how it can be used to bootstrap cli
  app development really quickly & with minimal boilerplate.FYI, this help
  block uses chalk template syntax.

Examples

  $ test foo [file]
  $ test bar

Commands:

  foo   f   this foo command does foo stuff
  bar   b   the bar command does bar things

Example output from: $ ts-node foo.ts help foo:

foo command

  This command uses a bunch of different options, including required options.

examples

  $ cmd foo <file>
  $ cmd foo -r <file>

Options

  -r, --raw         use raw input, for example
  -f, --file file   file to read

Example output from: $ ts-node foo.ts help bar:

bar command

  This command has an option that can be used multiple times. The value that's
  passed to the function will be a string array.

examples

  $ test bar -m first -m second

Options

  -m, --multiple string   argument that can be used multiple times

Still here?

Here is all you need to know to use this thing.

@Command(object) (methods)

Make this function a command.

property	type	description
name	string (required)	the name of your (sub) command.
alias	string	alias for this command.
description	string	used to describe this sub command in the help menu.
help	HelpSection	used when your cmd is run with $ cmd help <subcommand-name>

@Opt(object) (parameters)

property	type	description
name	string (required)	the name of your param. Should probably match the parameters name
alias	string	alias for this option.
required	boolean	whether or not this option is required. If it is required and not provided when the command is executed, the program will print a warning and exit.
description	string	used to describe this param in the help menu.

Also includes all of the properties specified by command-line-args OptionDefinition and those specified by command-line-usage OptionDefinition.

@Help(HelpArgs) (classes)

Create a help menu using command-line-usage which will show up when the user runs $ help or $ --help.

bootstrap(object)

Once you've created your class and decorated it with the above ☝️ decorators, you will probably want to run it. Luckily, this is pretty easy. Just import the bootstrap function from clidec and pass an instance of your class to it.

Important

Remember you NEED TO add this the compilerOptions section of your tsconfig.json:

    "experimentalDecorators": true,
    "emitDecoratorMetadata": true,

Future:

• Add some tests. This is a rush job.
• Add some kind of 'devMode' option for the bootstrap function which runs a bunch of sanity checks to make sure all the decorators are set up right.
• Add a 'middleware' system so you could handle different output types.
• Add a nice error handler. Maybe support for async functions too.