Create a Custom Odoo 18 Module (From Scratch)

In this tutorial, we'll walk through creating a custom module in Odoo 18, step by step. This is based on Dockerized VPS setup, where you are building odoo with docker container and official odoo 18 image. where .odoo-bin may not be available to scaffold the file structure. 

Prerequisites

Make sure you have:

• An Odoo 18 instance running (Docker container preferred)
• Access to /mnt/extra-addons (your custom addons folder)
• Terminal access (SSH into your server)
• Basic Git setup (optional but recommended)

1: Create Your Module Folder

SSH into your VPS and create a new directory under /mnt/extra-addons.

cd /mnt/extra-addons/
mkdir qr_code_scanner
cd qr_code_scanner

2: Create Required Files

Every Odoo module must have at least:

• __init__.py — tells Odoo it's a Python package
• __manifest__.py — describes the module metadata

Create them:

touch __init__.py
touch __manifest__.py

3: Write the Manifest

Open __manifest__.py and paste the following:

{
    'name': 'QR Code Scanner',
    'version': '18.0.1.0', //use the format 18.0.x.y
    'summary': 'Scan QR codes and send emails to sales entries',
    'description': 'An app to scan QR codes and send emails to sales entries.',
    'author': 'Cedric Liu',
    'category': 'Sales',
    'license': 'LGPL-3',
    'depends': ['base', 'sale'],
    'data': [],
    'installable': True,
    'application': True,
    'auto_install': False
}

⚡ Important tips:

• Version must match 18.0.x.y format.
• Always specify 'license': 'LGPL-3' to avoid warnings.
• Make sure no trailing commas!

4: Restart Odoo Server

Tell Odoo to pick up the new module by restarting:

docker compose restart odoo

5: Update App List

1. Login to your Odoo backend (https://yourdomain.com/web).
2. Go to Apps → Update App List.
3. Click Update.

Now you should see your QR Code Scanner app!

6: (Optional) Git Version Control

assuming you are developing your custom module using git, you will ned to track your work by following:

cd /mnt/extra-addons/
git init
git remote add origin [email protected]:yourusername/odoo-custom-addons.git
git add qr_code_scanner
git commit -m "Initial commit - QR Code Scanner module"
git push -u origin main