This document describes how to contribute an app to CasaOS AppStore.
## Guidelines
A CasaOS App is a Docker Compose app, or a *compose app*.
Each directory under [Apps](Apps) correspond to a CasaOS App. The directory should contain at least a `docker-compose.yml` file:
- It should be a valid [Docker Compose file](https://docs.docker.com/compose/compose-file/).
- The `name` property is used as the *store App ID*, which should be unique across all apps.
For example, in the [`docker-compose.yml` of Syncthing](Apps/Syncthing/docker-compose.yml#L1), its store App ID is `syncthing`:
```yaml
name: syncthing
services:
syncthing:
image: linuxserver/syncthing:latest
...
```
- CasaOS specific metadata, also called *store info*, are stored under [extension](https://docs.docker.com/compose/compose-file/#extension) property `x-casaos` at two positions.
1. Service level
A `docker-compose.yml` file can contain one or more `services`. Each [service](https://docs.docker.com/compose/compose-file/#services-top-level-element) can have its own store info.
For the same example, at the buttom of the `syncthing` service in the [`docker-compose.yml` of Syncthing](Apps/Syncthing/docker-compose.yml)
```yaml
x-casaos:
author: CasaOS Team
category: Backup
container: # see Container store info (`x-casaos.container`) below
...
description: # multiple locales are supported
en_US: Syncthing is a continuous file synchronization program. It synchronizes files between two or more computers in real time, safely protected from prying eyes. Your data is your data alone and you deserve to choose where it is stored, whether it is shared with some third party, and how it's transmitted over the internet.
