Matrix federation

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<h1>Matrix federation</h1>

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* [Use case](#use-case)
* [Example configuration](#example-configuration)
  * [Disable federation](#disable-federation)
  * [Separate Matrix domain](#separate-matrix-domain)
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# Use case

The Element chat application and its server component Synapse are based on the Matrix protocol,
that supports federation with other Matrix servers to communicate with the users with accounts on these servers.

By default, you can chat with users that have an account within your openDesk installation and federate with other
matrix-based servers.
Federation support can be disabled.

# Example configuration

The following values are used in this example documentation.
Please ensure when you come across such a value,
even if it is part of a URL hostname or path, that you adapt it where needed to your setup:

- `opendesk.domain.tld`: the mandatory `DOMAIN` setting for your deployment resulting in
`https://chat.opendesk.domain.tld` to access the Element chat.
- `my_organization.tld`: an optional alternative domain used for mail and/or Matrix.
If not used it is also set to `opendesk.domain.tld`.

## Disable federation

The following setting can disable federation:

```yaml
functional:
  externalServices:
    matrix:
      federation:
        enabled: false
```

## Separate Matrix domain

If you want to federate with other Matrix instances and use a separate Matrix domain, you need to provide a JSON file on
the Matrix domain to use delegation.
This is not included inside openDesk.

Domain path: `https://my_organization.tld/.well-known/matrix/server`

Content:
```JSON
{
    "m.server": "matrix-federation.opendesk.domain.tld:443"
}
```

More detailed information can be found in Matrix/Synapse documentation:
[Matrix Delegation](https://matrix-org.github.io/synapse/v1.98/delegate.html)