Add checks for super user exists

ReadMe.md

@@ -21,11 +21,13 @@ Two files must be created
 
 Example file is `pgbackrest.sample.cfg`
 
-This file holds the sudo_user for calling the commands
+This file holds the sudo_user for calling the commands and the main pgbackrest config file.
+If the super user or config file does not exists an error will be shown
 
 ```ini
 [PgBackRest]
 sudo_user=postgres
+pgbackrest_config=/etc/pgbackrest.conf
 ```
 
 ### `config/stanza.cfg`
@@ -44,7 +46,14 @@ The forth optional parameter is the super user to use
 
 If parameters are not used but laters are, the empties need to be set with just the ":"
 
-`stanza::/conifg`
+`stanza::/config`
+
+The script checks for the following things during each run
+
+- stanza name exists in the main config file, or in the override config file if set
+- check if repo number exist in main config file, or in the override config file if set
+- override config file exists
+- override super does not exist
 
 ```ini
 [stanzas]

bin/pgbackrest_backup.sh

@@ -71,6 +71,10 @@ if [ -z "${sudo_user}" ]; then
 	echo "sudo_user not set in the config file ${config_file}";
 	exit;
 fi;
+if ! id "${sudo_user}" &>/dev/null; then
+	echo "Sudo user ${sudo_user} does not exist, skipping stanza";
+	exit
+fi;
 if [ -z "${pgbackrest_config}" ] ||[ ! -f "${pgbackrest_config}" ]; then
 	echo "Missing pgbackrest default config file ${pgbackrest_config}";
 	exit;
@@ -218,6 +222,10 @@ while read -r stanza; do
 	fi;
 	# set override sudo user
 	if [ -n "${stanza_super_user}" ]; then
+		if ! id "${stanza_super_user}" &>/dev/null; then
+			echo "[!] Sudo user ${stanza_super_user} for stanza ${stanza_name} does not exist, skipping stanza";
+			continue;
+		fi;
 		sudo_user="${stanza_super_user}";
 	fi;
 	# build the call command