commandir

Commandir pattern allows to scale command pattern with directories or URLs. Nodejs or browser.

Installation

npm install -s @allnulled/commandir

Importation

In node.js:

require("@allnulled/commandir");

In html:

<script src="node_modules/@allnulled/commandir/commandir.js"></script>

Usage

In node.js:

const commandir = Commandir.nodejs(__dirname + "/commands");

In browser:

const commandir = Commandir.browser("https://github.com/allnulled/path/to/file/raw");

The browser mode, which in fact means AJAX mode, is allowed in node.js too as it only uses fetch.

Then, in any:

commandir.execute("path/to/command.js", {
    parameter1: 1,
    parameter2: 2,
    parameter3: 3
});

You can, then, list(), register(name, callback) and unregister(name):

console.log(commandir.list());
commandir.register("salute", () => console.log("hi!"));
commandir.execute("salute");
commandir.unregister("salute");

Details

1. The objects module.exports and __dirname exist in both environments.

The only difference is that __dirname in browsers points to the URL of the script. But module.exports and return can be used in browser mode to return a module from the file.

2. The method register receive different parameters

In browser, register(name, url). In node.js, register(name, callback).

3. The methods register and unregister work differently

In browser, they just associate a label with a URL. In node.js, they write a file in the filesystem with the callback provided as second parameter, and remove it on unregister.

4. The method list cannot work in browser

Because directories in the web do not list by default, the method list is still not provided with a polyfill.

5. Names are fixed and sanitized

Names have a process of validation and transformation before they get registered. They rewrite the .js at the end, and forbid .. just in case.

For now, I think it is all.

Test

This is the example that the test uses. It is cross-environment but because we discriminated.

let basedir = ".";

const isNodejs = typeof global !== "undefined";

const main = async function () {
  if (isNodejs) {
    require(__dirname + "/../commandir.js");
    basedir = __dirname;
  }

  if (isNodejs) {
    const commandir = Commandir.nodejs(basedir + "/commands");
    commandir.execute("/hello", {
      dest: "world"
    });
    commandir.register("/goodbye", function (parameters) {
      console.log(`Goodbye, ${parameters.dest}!`);
    });
    commandir.execute("/goodbye", { dest: "world" });
    commandir.unregister("/goodbye");
    console.log(commandir.list(""));
  } else {
    const commandir = Commandir.browser("/test/commands");
    await commandir.register("hello", "./commands/hello.js");
    await commandir.execute("hello", { dest: "world" });
  }
};

main();