5.2: The Ideal Project Structure: Folder Organization (/app, /data, /conf)

Now that we know whyDockerCompose is useful, it’s important to learn how to organize our project properly.
A good structure allows you to:

Quickly understand your stack
Make maintenance easier
Share or version the project without any headaches

The recommended structure

Here is a classic and functional structure for a Compose projectDocker:

mon-projet/
├─ docker-compose.yml       # Décrit tous les services
├─ .env                     # Variables d’environnement (ports, mots de passe, etc.)
├─ app/                     # Code de l’application (site web, API, scripts)
│  ├─ index.php
│  └─ ...
├─ data/                    # Données persistantes (bases de données, uploads)
│  └─ mariadb/
├─ conf/                    # Fichiers de configuration (php.ini, nginx.conf, Traefik, etc.)
│  └─ ...
└─ logs/                    # Journaux d’activité si besoin

Folder descriptions

Folder	Content & role
app/	Contains all the application code. With a bind mount,Dockeryou can access your code directly from the container.
data/	Contains persistent volumes for databases or files generated by the application. Example: `./data/mariadb:/var/lib/mysql`.
conf/	Contains configuration files specific to your services. Example: `nginx.conf`, `php.ini`, `traefik.yml`.
logs/	Optional, for centralizing logs if you do not want to store them directly in the containers.
docker-compose.yml	Describes your services and how they interact. This is the core of the stack.
.env	Contains all your sensitive or configurable variables. Allows you to change the configuration without modifying the YAML.

Best practices

Separate code, configuration, and data: this simplifies backups and updates.
Always use a.env to avoid hard-coding passwords in the YAML.
Name your folders and services clearly: app, db,cache are preferable to service1, service2.
Never store important data solely in the container: containers can disappear. Use volumes.
Version control your project (Git) by excluding large data folders (/data) with .gitignore.

📌 Key Takeaways
A Compose projectDocker must be clean, readable, and maintainable.
/app for code, /data for persistent data, /conf for configurations.
.env for dynamic configuration.
This structure prepares you to manage more complex projects and collaborate with other developers.