@md/cli

Create a standardized CLI in a type-safe way.

import * as CLI from "@md/cli";

const commands: CLI.CommandMap = {
  example: CLI.command(
    {
      description: "Example command",
      arguments: ["two", "commands"], // This command requires two arguments
      flags: {
        boolean: {
          description: "A boolean flag with short form",
          type: "boolean", // True if present in arguments
          short: "b", // Can use -b instead of --boolean
        },
        valueEnum: {
          description: "A value flag for an enum",
          type: "value", // This flag should be a string value
          required: true, // False if omitted
          only: ["hello", "world"], // Could also be a regex or omitted for `any`
        },
      },
    } as const // Use `as const` to correctly infer flag validation
  ).runner((args, flags) => {
    // We now get the two validated arguments and typed flags
    console.log(args, flags); 
  }),
};
CLI.create("Example API", commands).run(); // Same as `CLI.create(...).run(Deno.args);`

Philosophy

Here is how the CLI created with @md/cli is structured:

command subcommand arg1 arg2 --boolflag -f --flag1 val1 --flags=val2 _/ _/ _____________________________/ Commands Arguments Flags

Commands

You first have 1 - many commands. Each command specifies how many arguments it takes and valid flags to be used with it.

Arguments

The arguments are fully variable values that are passed to the command

Flags

Flags have two types with two forms each:

Boolean flags

Boolean flags only signal true or false such as --example and can have a short form e.g., -e

Value flags

Value flags carry with them some information and can come in the form --example value or --example=value. Each value flag only has one value associated to it.