Event Handling

The Client class extends the EventEmitter (opens in a new tab) class from Node.js. This means that you can listen to events emitted by the client.

Visit the API Reference page to see all events emitted by the client.

Individual Events Files

Your project directory should look like this:

index.js
package.json

Let's create a new folder called events and create a new file called message.js inside it. This file will be responsible for handling the message event.

index.js
package.json
- message.js

Now, let's add the following code to the message.js file:

events/message.js

module.exports = {
    name: 'message',
 
    run: async (client, message) => {
        console.log(message)
    },
}

The name property is the name of the event. The once property is a boolean that indicates whether the event should be executed only once or not. The run property is the function that will be executed when the event is emitted.

Reading Events Files

Now that we have created the message.js file, we need to read it and register the event. To do this, we will use the readdir function from the fs module.

index.js

const { Client } = require('chat-bridge')
const dotenv = require('dotenv')
const path = require('path')
const fs = require('fs')
 
dotenv.config()
 
const client = new Client({
    accessToken: process.env.ACCESS_TOKEN,
    verifyToken: process.env.VERIFY_TOKEN,
})
 
const eventsDir = path.join(__dirname, 'events')
const eventFiles = fs.readdirSync(eventsDir).filter((file) => file.endsWith('.js'))
 
for (const file of eventFiles) {
    const event = require(path.join(eventsDir, file))
    if (event.once) {
        client.once(event.name, (...args) => event.run(client, ...args))
    } else {
        client.on(event.name, (...args) => event.run(client, ...args))
    }
}
 
client.start(() => {
    console.log('Bot is running')
})

Look pretty good, right? But we can do better.

Step 1: Clarify the Purpose of index.js in the events Folder:

In the events folder, create a new file called index.js. This file will be responsible for reading and registering the event files.

events/index.js

const path = require('path')
const fs = require('fs')
 
module.exports = (client) => {
    // rest of the code
}

Step 2: Simplify the Event Registration Loop:

You can use for...of directly on the filtered array of event files, eliminating the need for the separate eventsDir variable.

events/index.js

const path = require('path')
const fs = require('fs')
 
module.exports = (client) => {
    const eventsDir = path.join(__dirname)
    const eventFiles = fs.readdirSync(eventsDir).filter((file) => file.endsWith('.js'))
 
    for (const file of eventFiles) {
        const event = require(path.join(__dirname, file))
        const eventHandler = (...args) => event.run(client, ...args)
 
        if (event.once) {
            client.once(event.name, eventHandler)
        } else {
            client.on(event.name, eventHandler)
        }
    }
}

Now, we can create new files inside the events folder and they will be automatically read and registered.

💡

Tip: You can use the once property to register events that should be executed only once.

Step 3: Load the Events Folder:

Now, we need to load the events folder. To do this, we will import the events folder in the index.js file and pass the client instance as an argument.

index.js

const { Client } = require('chat-bridge')
const events = require('./events')
const dotenv = require('dotenv')
 
dotenv.config()
 
const client = new Client({
    accessToken: process.env.ACCESS_TOKEN,
    verifyToken: process.env.VERIFY_TOKEN,
})
 
events(client)
 
client.start(() => {
    console.log('Bot is running')
})

Congratulations! You've successfully organized your event handling by creating an index.js file in the events folder. Now, new event files added to the events folder will be automatically read and registered when your bot starts.

Set Client Options API Reference