Tramway Command is a simple CLI building tool to write scripts to accompany a Tramway project built in ES2015+. It includes:

1. A standard interface for writing commands.
2. A flexible way to create multiple namespaces.
3. An indexing system capable of plugging into tramway-core-dependency-injector and avoiding file clutter
4. Control of argument names, types and if they're required
5. Terminal utilities to aide in creating rich terminal applications

Installation:

1. npm install tramway-command

Example project:

https://gitlab.com/tramwayjs/tramway-command-example

Documentation

Recommended Folder Structure

• config
• commands

Config

The config file for commands will contain a JSON hashmap of commands to a string representation.

import TestCommand from '../commands/TestCommand';
export default {
    "test:command": TestCommand
};

Commands

Commands let you perform and automate tasks or create helpful utilities without needing to create a GUI.

To create a command, import the class and implement a derived class with the abstracted stubs to get the most out of it.

import {Command, commands} from 'tramway-command';
let {InputOption} = commands;

export default class TestCommand extends Command {
    configure() {
        this.args.add((new InputOption('input', InputOption.string)).isRequired());
        this.options.add(new InputOption('str', InputOption.string));
        this.options.add((new InputOption('num', InputOption.number)).isRequired());
        this.options.add(new InputOption('arr', InputOption.array));
        this.options.add(new InputOption('bool', InputOption.boolean));
    }

    action() {
        console.log("Test command ran, here's some of what you gave it", this.arguments, this.options);
    }
}

Function	Usage
constructor()	Handles any dependency injection that can instantiated in the index or using tramway-core-dependency-injector
action()	The main runner of the command, will be executed when the index maps the CLI to it.
configure()	The configuration of the command, determines argument mapping and the order. Here is where InputOption objects are instantiated
getArgument(name)	Does not need to be implemented, gives access to the value of the mapped argument. (See Input Option section)
getOption(name)	Does not need to be implemented, gives access to the value of the option. (See Input Option section)

Input Option

All arguments start as InputOption objects which handle and validate your inputs.

An argument is the ordered sequence of input after the command name in the CLI. An option is a mapped key-value pair from the CLI and can be added in any order.

The constructor arguments are as follows:

Argument	Usage
name	The name of the argument used to access it both programmatically and in the CLI
type	One of the main pre-defined types in the InputOption object. Your input value will be cast to this type
defaultValue	The default value the command will recieve if the argument or option isn't given one

Some extra functionality can be added, for now we can determine if an option is required by setting the required flag using the isRequired function. By default no arguments or options are set to required. An exception will be thrown in the event that a required option/argument isn't present.

Any extra and undeclared options will be ignored at runtime.

Spinning up commands with the Command Resolver

The CommandResolver encapsulates the necessary logic to turn an index of commands into a powerful namespace that let's you use commmands as classes in any directory you want in the project. NodeJS can run any file so the most convenient way to get a desirable executable path is to create the dedicated commands runner file in the root of your project (or the root of your dev directory that will be transpiled).

Depending how you set up the command resolver, the command format will generally follow this template when running it in a terminal:

node namespace command-name [arguments] [options]

To achieve a simple CLI that takes the following format:

node command test-command arg1 --option1 5

You will need to create a command.js file in the dev directory of a typical tramway project. It will be transpiled at the root of your app.

Inside the command.js file, you will want to import the index, instantiate the Command Resolver and run it.

import {commands} from 'tramway-command`;
let {CommandResolver} = commands;
import index from './config/commands.js';

export default (new CommandResolver(index)).run();

The namespace is determined by the name of the file and you can create multiple namespaces with multiple namespace-specific indexes with the code above. For example, if you wanted to make commands specifically for migrations, you could also add a migrations.js file with the command resolver and run migrations via node migrations someMigrationCommand.

Extending the CommandResolver

The CommandResolver will try to build command classes from its internal mapping in the command.js by default, using a CommandFactory. The default setup is convenient when tramway-command is used as a standalone solution but it can be limiting when used with other Tramway components, notably tramway-core-dependency-injector. The Command Resolver takes a second argument in the constructor to allow for custom Command factories to be used instead of the default one, like tramway-command-di-factory if you want to leverage the dependency injection library.

Example:

import DICommandFactory from 'tramway-command-di-factory';
export default (new CommandResolver(index, new DICommandFactory())).run();

Note that the above code snippet can be implemented as a core service in your dependency injection config.

import CommandResolver from 'tramway-command';
import DICommandFactory from 'tramway-command-di-factory';

export default {
    "app": {
        "class": CommandResolver,
        "constructor": [
            {"type": "parameter", "key": "commands"},
            {"type": "service", "key": "factory.command"},
        ],
    },
    "factory.command": {
        "class": DICommandFactory,
    }
}

Terminal Utilities

Tramway Command implements wrappers for terminal-kit.

import {terminal} from 'tramway-command';

Console message formatting

Information: Prints a message in blue.

const {Message, TimestampLog} = terminal;
new Message('message');
new TimestampLog('message')

Success: Prints a message in green.

const {SuccessMessage, TimestampSuccess} = terminal;
new SuccessMessage('message');
new TimestampSuccess('message')

Warning: Prints a message in yellow.

const {WarningMessage, TimestampWarning} = terminal;
new WarningMessage('message');
new TimestampWarning('message')

Error: Prints a message in red.

const {ErrorMessage, TimestampError} = terminal;
new ErrorMessage('message');
new TimestampError('message')

Progress Bar

const {ProgressBar} = terminal;

Argument	Usage
title	The name of the argument used to access it both programmatically and in the CLI
items	One of the main pre-defined types in the InputOption object. Your input value will be cast to this type
options	The default value the command will recieve if the argument or option isn't given one

The ProgressBar includes the following methods:

Function	Usage
start(task: string)	Starts a task, increments progress
finish(task: string)	Finishes a task, increments progress
pause()	Pauses the current progress bar
resume()	Resumes the progress bar from the state it left off
isComplete(): boolean	Determine if the progress bar is at 100%