envoy/README.md

# Envoy

<img src="https://git.kske.dev/repo-avatars/33-31e14133097b01b748ab361e3c3adb47" style="display: block" width="150" height="150">

Envoy is a messenger written in Java.
On this page, the project is explained for different user groups.

## Regular User

To use Envoy to join an existing server, download the client from the [release page](https://git.kske.dev/zdm/envoy/releases).

When starting it for the first time, you can register yourself at a server of your choice.
After connecting to the server, you can add other users to your contact list and send them messages.

To chat with multiple users at once, you can create a group.
If you want to transfer a file to another user, you can attach it to a message.

On the settings page some convenience features can be configured, as well as the color theme.

### System requirements

To run Envoy, you have to install a Java Runtime Environment (JRE) of at least version 11.
You can download an open source implementation from [here](https://jdk.java.net/15/).

If you are running a Linux distribution, make sure that an emoji font like [Noto emoji](https://github.com/googlefonts/noto-emoji) is installed.
Most major Linux distributions like Debian, Arch and Gentoo have a Noto emoji package available inside their package repositories.

## Server Administrator

To set up an Envoy server, download the package from the release page.

Because the project lacks external documentation for the moment, please refer to the Javadoc inside the source code to configure your Envoy instance.

### System requirements

To run Envoy server, you have to install a JRE as mentioned above, as well as a database.
In development, PostgreSQL is used, which you can download from [here](https://www.postgresql.org/download/).

Look at the file `META-INF/persistence.xml` inside `envoy-server.jar` for the database configuration.

After creating a database and configuring the credentials, the server will initialize the necessary tables automatically.

## Programmer

Envoy is organized as a Maven project that is split into three modules.

### Client

* Sending and receiving of messages, groups, sending images and voice messages
* User interface (UI)
* Client configuration
* Advanced logging possibilities
* Tons of Events to interact with
* Detailed Javadoc to improve readability of code

### Common
* Basic datatypes
* Events sent between client and server
* Configuration API
* Logging API based on `java.util.logging`
* Envoy-specific Exception
* Useful utility classes

### Server
* Non-blocking connectivity infrastructure based on `java.nio`
* Processors to handle incoming events
* Database connectivity
* Database entities
* Utility classes to check client version compatability and password validity