scripts: Add a check on minion ID in bootstrap

The check validates that the Salt minion ID
follows the RFC1123 since this ID will be used
for the Kubernetes Node name.

Refs: #3258

scripts/bootstrap.sh.in

@@ -167,7 +167,6 @@ check_ca_minion() {
     fi
 }
 
-
 main() {
     run "Determine the OS" determine_os
     if [ -z "${PYTHON:-}" ]; then
@@ -181,6 +180,7 @@ main() {
     run "Disabling Salt minion service" disable_salt_minion_service
     run "Stopping Salt minion service" stop_salt_minion_service
     run "Installing mandatory packages" install_packages "${PACKAGES[@]}"
+    run "Checking Salt minion ID" check_minion_id
     run "Configuring Salt minion to run in local mode" configure_salt_minion_local_mode
     run "Ensure archive is available" ensure_archives_mounted
     run "Calculating Salt grains in local mode" set_local_grains

scripts/common.sh.in

@@ -370,7 +370,7 @@ get_salt_env() {
 }
 
 get_salt_minion_id() {
-    "$SALT_CALL" --out txt grains.get id | cut -c 8-
+    "$SALT_CALL" --local --out txt grains.get id | cut -c 8-
 }
 
 get_salt_minion_ids() {
@@ -404,3 +404,22 @@ retry() {
 
     echo "$stdout"
 }
+
+check_minion_id() {
+    # Minion ID is used as the Kubernetes Node name, so it must follow the
+    # RFC1123 (https://tools.ietf.org/html/rfc1123).
+    # This means the name must:
+    #   - contain no more than 253 characters
+    #   - contain only lowercase alphanumeric characters, '-' or '.'
+    #   - start with an alphanumeric character
+    #   - end with an alphanumeric character
+    minion_id=$(get_salt_minion_id)
+
+    if ! [[ $minion_id =~ ^(([0-9a-z][0-9a-z.-]{0,251}[0-9a-z])|[0-9a-z])$ ]]; then
+        echo "Invalid Salt minion ID '$minion_id': The ID must be compliant" \
+             "with RFC1123, which means it must contain no more than 253" \
+             "characters, contain only lowercase alphanumeric characters, '-'" \
+             "or '.' and start and end with an alphanumeric character."
+        return 1
+    fi
+}

scripts/restore.sh.in

@@ -335,6 +335,7 @@ run "Disabling Salt minion service" disable_salt_minion_service
 run "Stopping Salt minion service" stop_salt_minion_service
 run "Configuring local repositories" configure_repositories
 run "Installing mandatory packages" install_packages "${PACKAGES[@]}"
+run "Checking Salt minion ID" check_minion_id
 run "Configuring Salt minion to run in local mode" configure_salt_minion_local_mode
 
 run "Restoring MetalK8s configurations" restore_metalk8s_conf