WebDAV

Enable modules

sudo a2enmod dav
sudo a2enmod dav_fs
sudo a2enmod auth_digest

Add user

sudo mkdir -p /usr/local/apache/var/
sudo chown www-data:www-data /usr/local/apache/var

sudo touch /usr/local/apache/var/users.password
sudo chown www-data:www-data /usr/local/apache/var/users.password

sudo htdigest /usr/local/apache/var/users.password webdav your_username

Site configuration

DavLockDB /usr/local/apache/var/DavLock
<VirtualHost *:80>
    ServerName webdav.example.com
    ServerAdmin webmaster@localhost
    DocumentRoot /var/www/webdav/

    ErrorLog ${APACHE_LOG_DIR}/webdav.error.log
    CustomLog ${APACHE_LOG_DIR}/webdav.access.log combined

    RemoveHandler .php
    RemoveType .php
    php_admin_value engine Off

    <Directory /var/www/webdav>
        DAV On
        AuthType Digest
        AuthName "webdav"
        AuthUserFile /usr/local/apache/var/users.password
        Require valid-user

        Options Indexes FollowSymLinks MultiViews
        AllowOverride all
        Require all granted
        DirectoryIndex disabled
    </Directory>
</VirtualHost>

Test cfg and restart

sudo apachectl configtest
sudo systemctl restart apache2.service