How can I include a code from another file commands - node.js

Question

I am using this code, and what I want is for the commands to come from another file to make the index.js cleaner
const tmi = require('tmi.js');
const client = new tmi.Client({
options: { debug: true },
channels: [ 'my_name' ]
});
client.connect();
client.on('message', (channel, tags, message, self) => {
// Ignore echoed messages.
if(self) return;
if(message.toLowerCase() === '!hello') {
// "#alca, heya!"
client.say(channel, `#${tags.username}, heya!`);
}
});
In the index include the code
// index.js
// ======
var commands = require('./commands');
const tmi = require('tmi.js');
var commands = require('./commands');
const client = new tmi.Client({
options: { debug: true },
channels: [ 'my_name' ]
});
client.connect();
client.on('message', (channel, tags, message, self) => {
// Ignore echoed messages.
if(self) return;
// I replace the command with the file
commands();
});
I have the commands file structured in this way.
// commands.js
// ========
module.exports = function (channel, tags, message, self) {
if(message.toLowerCase() === '!hello') {
// "#alca, heya!"
client.say(channel, `#${tags.username}, heya!`);
}
}
But it doesn't work for me, I don't know what I'm doing wrong.
I have republished it from a new account, it has not allowed me to access the one with which I made the query. And it does not allow me to vouch for the lack of reputation. How can I include a code from another file
Responding to #jabaa's answer.
The problem you have when typing !hello should give the answer Heya! which would be client.say(channel, #${tags.username}, heya!);
#Dave Newton the intention is only to load the information from commands.js so that the index is cleaner if I use the direct code it works but when I use Commands(); It doesn't make any response.

Answer 1

Assuming you have 2 files in the same directory
/foo/bar/commands.js
/foo/bar/main.js
You can define commands.js like this:
exports = module.exports = {
someFunction,
anotherFunction,
}
function someFunction(text) {
console.log(`in someFunction: ${text}`);
}
function anotherFunction(text) {
console.log(`in anotherFunction(): ${text}`);
}
And then you can pull that into main.js like so:
const cmds = require('./commands');
cmds.someFunction('hello, there!');
cmds.anotherFunctio('and again!');
and get the following written to the console:
in someFunction(): hello, there!
in anotherFunction(): and again!
If you set the default export as the function itself,
exports = modules.exports = someFunction(text) {
console.log(`in someFunction(): ${text}`);
}
Then what's returned from the require() is that function:
const foo = require('./commands.js');
foo('hello, there!'):
and running that you get:
in someFunction(): hello, there!