Add minecraft restic hook

roles/restic/files/hooks/minecraft.sh

@@ -0,0 +1,96 @@
+#!/bin/bash
+
+SERVICE=minecraft.service
+VAR_DIR=/opt/minecraft/var
+WAIT=30
+VERBOSE=${VERBOSE:-4}
+
+error_exit() {
+    printf "%s\n" "$1" >&2
+    exit 1
+}
+
+stop_server() {
+    local unit="${1:-$SERVICE}"
+    local attempts="${2:-$WAIT}"
+
+    if ! systemctl -q is-active "$unit"; then
+        printf "%s is already stopped\n" "$unit"
+        return 0
+    fi
+
+    systemctl -q stop "$unit"
+
+    while systemctl -q is-active "$unit"; do
+        printf "waiting for %s to stop ... (%s)\n" "$unit" "$attempts"
+        ((attempts--))
+        if ((attempts == 0)); then
+            return 1
+        fi
+        sleep 1
+    done
+
+    return 0
+}
+
+start_server() {
+    local unit="${1:-$SERVICE}"
+    local attempts="${2:-$WAIT}"
+
+    if systemctl -q is-active "$unit"; then
+        printf "%s is already started\n" "$unit"
+        return 0
+    fi
+
+    systemctl -q start "$unit"
+
+    while ! systemctl -q is-active "$unit"; do
+        printf "waiting for %s to start ... (%d)\n" "$unit" "$attempts"
+        ((attempts--))
+        if ((attempts == 0)); then
+            return 1
+        fi
+        sleep 1
+    done
+
+    return 0
+}
+
+
+open_files() {
+    local dir=${1-$VAR_DIR}
+    local attempts="${2:-$WAIT}"
+
+    while (($(lsof +D "$dir" | wc -l) > 0)); do
+        printf "waiting for open files ... (%d)\n" "$attempts"
+        ((attempts--))
+        if ((attempts == 0)); then
+            return 1
+        fi
+        sleep 1
+    done
+
+    return 0
+}
+
+
+main() {
+    if [ "$1" == "pre" ]; then
+        printf "stopping %s\n" $SERVICE
+        if ! stop_server $SERVICE; then
+            error_exit "Failed to stop $SERVICE"
+        fi
+
+        printf "checking for open files\n"
+        if ! open_files $VAR_DIR; then
+            error_exit "Open files exist in $VAR_DIR"
+        fi
+    elif [ "$1" == "post" ]; then
+        printf "starting %s\n" $SERVICE
+        if ! start_server $SERVICE; then
+            error_exit "Failed to start $SERVICE"
+        fi
+    fi
+}
+
+main "$@"