Add backup script (no restore yet)

scripts/backup

@@ -0,0 +1,24 @@
+#!/bin/bash
+set -e # Exit on error
+
+app=mattermost
+
+# The parameter $1 is the backup directory location
+# which will be compressed afterward
+backup_dir=$1/apps/$app
+sudo mkdir -p $backup_dir
+
+# Backup sources
+sudo cp -a /var/www/$app/. $backup_dir/sources
+
+# Backup database
+root_pwd=$(sudo cat /etc/yunohost/mysql)
+sudo sh -c "mysqldump -u root -p$root_pwd mattermost > $backup_dir/mattermost.sql"
+
+# Backup uploaded files
+sudo cp -a /home/yunohost.app/mattermost/. $backup_dir/data
+
+# Copy Nginx and YunoHost parameters to make the script "standalone"
+sudo cp -a /etc/yunohost/apps/$app/. $backup_dir/yunohost
+domain=$(sudo yunohost app setting $app domain)
+sudo cp -a /etc/nginx/conf.d/$domain.d/$app.conf $backup_dir/nginx.conf