---
title: NextCloud
---

## What is NextCloud

From https://en.wikipedia.org/wiki/Nextcloud

:::note
Nextcloud is a suite of client-server software for creating and using file hosting services. Nextcloud is free and open-source, which means that anyone is allowed to install and operate it on their own private server devices.
:::

:::warning
This setup only works, when NextCloud is running with HTTPS enabled. See [here](https://docs.nextcloud.com/server/stable/admin_manual/configuration_server/reverse_proxy_configuration.html?highlight=overwriteprotocol#overwrite-parameters) on how to configure this.
:::

:::warning
In case something goes wrong with the configuration, you can use the URL `http://nextcloud.company/login?direct=1` to log in using the built-in authentication.
:::

## Preparation

The following placeholders will be used:

-   `nextcloud.company` is the FQDN of the NextCloud install.
-   `authentik.company` is the FQDN of the authentik install.

Create an application in authentik and note the slug you choose, as this will be used later. In the Admin Interface, go to Applications->Providers. Create a SAML provider with the following parameters:

-   ACS URL: `https://nextcloud.company/apps/user_saml/saml/acs`
-   Issuer: `https://authentik.company`
-   Service Provider Binding: `Post`
-   Audience: `https://nextcloud.company/apps/user_saml/saml/metadata`
-   Signing certificate: Select any certificate you have.
-   Property mappings: Select all Managed mappings.

You can of course use a custom signing certificate, and adjust durations.

## NextCloud

In NextCloud, ensure that the `SSO & SAML Authentication` app is installed. Navigate to `Settings`, then `SSO & SAML Authentication`.

Set the following values:

-   Attribute to map the UID to.: `http://schemas.goauthentik.io/2021/02/saml/username`
-   Optional display name of the identity provider (default: "SSO & SAML log in"): `authentik`
-   Identifier of the IdP entity (must be a URI): `https://authentik.company`
-   URL Target of the IdP where the SP will send the Authentication Request Message: `https://authentik.company/application/saml/<application-slug>/sso/binding/redirect/`
-   URL Location of IdP where the SP will send the SLO Request: `https://authentik.company/if/session-end/<application-slug>/`
-   Public X.509 certificate of the IdP: Copy the PEM of the Selected Signing Certificate

Under Attribute mapping, set these values:

-   Attribute to map the displayname to.: `http://schemas.xmlsoap.org/ws/2005/05/identity/claims/name`
-   Attribute to map the email address to.: `http://schemas.xmlsoap.org/ws/2005/05/identity/claims/emailaddress`
-   Attribute to map the users groups to.: `http://schemas.xmlsoap.org/claims/Group`

You should now be able to log in with authentik.

:::note
If Nextcloud is behind a reverse proxy you may need to force Nextcloud to use HTTPS.
To do this you will need to add the line `'overwriteprotocol' => 'https'` to `config.php` in the Nextcloud `config\config.php` file
See https://docs.nextcloud.com/server/latest/admin_manual/configuration_server/reverse_proxy_configuration.html#overwrite-parameters for additional information
:::

## Group Quotas

Create a group for each different level of quota you want users to have. Set a custom attribute, for example called `nextcloud_quota`, to the quota you want, for example `15 GB`.

Afterwards, create a custom SAML Property Mapping with the name `SAML NextCloud Quota`.
Set the _SAML Name_ to `nextcloud_quota`.
Set the _Expression_ to `return user.group_attributes().get("nextcloud_quota", "1 GB")`, where `1 GB` is the default value for users that don't belong to another group (or have another value set).

## Admin Group

To give authentik users admin access to your NextCloud instance, you need to create a custom Property Mapping that maps an authentik group to "admin". It has to be mapped to "admin" as this is static in NextCloud and cannot be changed.

Create a SAML Property mapping with the SAML Name "http://schemas.xmlsoap.org/claims/Group" and this expression:

```python
for group in user.ak_groups.all():
    yield group.name
if ak_is_group_member(request.user, name="<authentik nextcloud admin group's name>"):
    yield "admin"
```

Then, edit the NextCloud SAML Provider, and replace the default Groups mapping with the one you've created above.