First commit

Ensure running and autoshutdown scripts

.gitignore

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+*.swp

autoshutdown.sh

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+#!/bin/sh
+
+# If exists tmux session
+# If Responds to queries
+
+SERVER_DIR='/home/ubuntu/minecraft/servers/kincls'
+TMUX_NAME='minecraft kincls server'
+EMPTY_COUNTER="$SERVER_DIR/empty_counter.txt"
+
+json_parse() {
+    cat - | python3 -c "import sys, json; print(json.load(sys.stdin)['$1'])"
+}
+
+silent_exitcode() {
+    $* > /dev/null 2>&1
+}
+
+empty_count() {
+    if [ ! -f "$EMPTY_COUNTER" ]; then
+        # File not existing
+        echo "0"
+    else
+        cat "$EMPTY_COUNTER"
+    fi
+}
+
+empty_incr() {
+    c="$(empty_count)"
+    if [ "$c" -gt 10 ]; then
+        echo "Server empty for more than 10 minutes, shutting down"
+        empty_reset # Needs to be 0 next time server starts
+        tmux send-keys -t "$TMUX_NAME.0" "stop" ENTER
+        sleep 5
+        $(sudo /sbin/shutdown -P +1)
+    else
+        echo "Empty count $c. Incrementing"
+        echo "$((c+1))" > "$EMPTY_COUNTER"
+    fi
+}
+
+empty_reset() {
+    echo "Resetting empty counter"
+    echo 0 > "$EMPTY_COUNTER"
+}
+
+tmux_running() {
+    tmux ls -F "#{session_name}" | grep -q "$TMUX_NAME"
+}
+
+server_responsive() {
+    silent_exitcode mcstatus localhost ping
+}
+
+n_logins="$(w -h | wc -l)"
+echo "$(date) [$n_logins logins]"
+
+if tmux_running; then
+    : #echo "Tmux running"
+else
+    echo "Tmux not running"
+    empty_incr
+    exit 1
+fi
+
+if server_responsive; then
+    n_players=$(mcstatus localhost json | json_parse player_count)
+    echo "Server responsive. $n_players players online"
+    if [ "$n_players" -gt 0 ] || [ "$n_logins" -gt 0 ]; then
+        # Keep alive if players or ssh sessions active
+        empty_reset
+    else
+        empty_incr
+        exit 1
+    fi
+else
+    echo "Server unresponsive"
+    empty_incr
+    exit 1
+fi

crontab

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+* * * * * /home/ubuntu/minecraft/autoshutdown.sh

ensure_running.sh

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+#!/bin/bash
+
+cd servers/kincls
+tmux new-session -Ad -s "minecraft kincls server" "java -Xmx1024M -Xms1024M -jar server.jar nogui"