feat: add minecraft backup integration

src/Dockerfile

@@ -1,11 +1,82 @@
-FROM restic/restic:0.9.6
+FROM alpine AS builder
 
-RUN apk update && apk add python3 dcron mariadb-client postgresql-client
+RUN mkdir -p /opt
+
+ARG IMAGE_ARCH=amd64
+
+ARG RCON_CLI_VERSION=1.4.4
+
+ADD https://github.com/itzg/rcon-cli/releases/download/${RCON_CLI_VERSION}/rcon-cli_${RCON_CLI_VERSION}_linux_${IMAGE_ARCH}.tar.gz /tmp/rcon-cli.tar.gz
+
+RUN tar x -f /tmp/rcon-cli.tar.gz -C /opt/ && \
+    chmod +x /opt/rcon-cli
+
+ARG RESTIC_VERSION=0.9.5
+
+ADD https://github.com/restic/restic/releases/download/v${RESTIC_VERSION}/restic_${RESTIC_VERSION}_linux_${IMAGE_ARCH}.bz2 /tmp/restic.bz2
+
+RUN bunzip2 /tmp/restic.bz2 && \
+    mv /tmp/restic /opt/restic && \
+    chmod +x /opt/restic
+
+ARG DEMOTER_VERSION=0.1.0
+
+ADD https://github.com/itzg/entrypoint-demoter/releases/download/${DEMOTER_VERSION}/entrypoint-demoter_${DEMOTER_VERSION}_linux_${IMAGE_ARCH}.tar.gz /tmp/entrypoint-demoter.tar.gz
+
+RUN tar x -f /tmp/entrypoint-demoter.tar.gz -C /opt/ && \
+    chmod +x /opt/entrypoint-demoter
+
+ARG RCLONE_VERSION=1.49.5
+
+ADD https://downloads.rclone.org/v${RCLONE_VERSION}/rclone-v${RCLONE_VERSION}-linux-${IMAGE_ARCH}.zip /tmp/rclone.zip
+
+RUN mkdir -p /tmp/rclone && \
+    unzip /tmp/rclone.zip -d /tmp/rclone && \
+    mv /tmp/rclone/rclone-v${RCLONE_VERSION}-linux-${IMAGE_ARCH}/rclone /opt/rclone && \
+    chmod +x /opt/rclone
+
+
+FROM alpine
+
+RUN apk -U --no-cache add \
+    bash \
+    coreutils \
+    openssh-client \
+    python3 \
+    dcron \
+    mariadb-client \
+    postgresql-client
+
+COPY --from=builder /opt/rcon-cli /opt/rcon-cli
+
+RUN ln -s /opt/rcon-cli /usr/bin
+
+COPY --from=builder /opt/restic /opt/restic
+
+RUN ln -s /opt/restic /usr/bin
+
+
+COPY --from=builder /opt/entrypoint-demoter /opt/entrypoint-demoter
+
+RUN ln -s /opt/entrypoint-demoter /usr/bin
+
+
+COPY --from=builder /opt/rclone /opt/rclone
+
+RUN ln -s /opt/rclone /usr/bin
+
+# install rcb python app
 
 ADD . /restic-compose-backup
 WORKDIR /restic-compose-backup
+
 RUN pip3 install -U pip setuptools wheel && pip3 install -e .
 ENV XDG_CACHE_HOME=/cache
 
+# end install
+
+ADD backup.sh /backup.sh
+RUN chmod +x ./backup.sh
+
 ENTRYPOINT []
 CMD ["./entrypoint.sh"]

src/backup.sh

@@ -0,0 +1,162 @@
+#!/bin/bash
+
+set -euo pipefail
+
+if [ "${DEBUG:-false}" == "true" ]; then
+  set -x
+fi
+
+: "${RCON_HOST:=localhost}"
+: "${RCON_PORT:=25575}"
+: "${RCON_PASSWORD:=minecraft}"
+
+export RCON_HOST
+export RCON_PORT
+export RCON_PASSWORD
+
+###############
+##  common   ##
+## functions ##
+###############
+
+is_elem_in_array() {
+  # $1 = element
+  # All remaining arguments are array to search for the element in
+  if [ "$#" -lt 2 ]; then
+    log INTERNALERROR "Wrong number of arguments passed to is_elem_in_array function"
+    return 2
+  fi
+  local element="${1}"
+  shift
+  local e
+  for e; do
+    if [ "${element}" == "${e}" ]; then
+      return 0
+    fi
+  done
+  return 1
+}
+
+log() {
+  if [ "$#" -lt 1 ]; then
+    log INTERNALERROR "Wrong number of arguments passed to log function"
+    return 2
+  fi
+  local level="${1}"
+  shift
+  local valid_levels=(
+    "INFO"
+    "WARN"
+    "ERROR"
+    "INTERNALERROR"
+  )
+  if ! is_elem_in_array "${level}" "${valid_levels[@]}"; then
+    log INTERNALERROR "Log level ${level} is not a valid level."
+    return 2
+  fi
+  (
+    # If any arguments are passed besides log level
+    if [ "$#" -ge 1 ]; then
+      # then use them as log message(s)
+      <<<"${*}" cat -
+    else
+      # otherwise read log messages from standard input
+      cat -
+    fi
+    if [ "${level}" == "INTERNALERROR" ]; then
+      echo "Please report this: https://github.com/itzg/docker-mc-backup/issues"
+    fi
+  ) | awk -v level="${level}" '{ printf("%s %s %s\n", strftime("%FT%T%z"), level, $0); fflush(); }'
+} >&2
+
+retry() {
+  if [ "$#" -lt 3 ]; then
+    log INTERNALERROR "Wrong number of arguments passed to retry function"
+    return 1
+  fi
+
+  # How many times should we retry?
+  # Value smaller than zero means infinitely
+  local retries="${1}"
+  # Time to sleep between retries
+  local interval="${2}"
+  readonly retries interval
+  shift 2
+
+  if (( retries < 0 )); then
+    local retries_msg="infinite"
+  else
+    local retries_msg="${retries}"
+  fi
+
+  local i=-1 # -1 since we will increment it before printing
+  while (( retries >= ++i )) || [ "${retries_msg}" != "${retries}" ]; do
+    # Send SIGINT after 5 minutes. If it doesn't shut down in 30 seconds, kill it.
+    if output="$(timeout --signal=SIGINT --kill-after=30s 5m "${@}" 2>&1 | tr '\n' '\t')"; then
+      log INFO "Command executed successfully ${*}"
+      return 0
+    else
+      log ERROR "Unable to execute ${*} - try ${i}/${retries_msg}. Retrying in ${interval}"
+      if [ -n "${output}" ]; then
+        log ERROR "Failure reason: ${output}"
+      fi
+    fi
+    # shellcheck disable=SC2086
+    sleep ${interval}
+  done
+  return 2
+}
+
+is_function() {
+  if [ "${#}" -ne 1 ]; then
+    log INTERNALERROR "is_function expects 1 argument, received ${#}"
+  fi
+  name="${1}"
+  [ "$(type -t "${name}")" == "function" ]
+}
+
+call_if_function_exists() {
+  if [ "${#}" -lt 1 ]; then
+    log INTERNALERROR "call_if_function_exists expects at least 1 argument, received ${#}"
+    return 2
+  fi
+  function_name="${1}"
+  if is_function "${function_name}"; then
+    eval "${@}"
+  else
+    log INTERNALERROR "${function_name} is not a valid function!"
+    return 2
+  fi
+}
+
+##########
+## main ##
+##########
+
+
+log INFO "waiting for rcon readiness..."
+# 20 times, 10 second delay
+retry 20 10s rcon-cli save-on
+
+
+if retry 5 10s rcon-cli save-off; then
+    # No matter what we were doing, from now on if the script crashes
+    # or gets shut down, we want to make sure saving is on
+    trap 'retry 5 5s rcon-cli save-on' EXIT
+
+    retry 5 10s rcon-cli save-all
+    retry 5 10s sync
+
+    rcb backup
+
+    retry 20 10s rcon-cli save-on
+    # Remove our exit trap now
+    trap EXIT
+  else
+    log ERROR "Unable to turn saving off. Is the server running?"
+    exit 1
+  fi
+
+  if (( PRUNE_BACKUPS_DAYS > 0 )); then
+    rcb cleanup
+  fi

src/crontab

@@ -1,2 +1,2 @@
-10 2 * * * source /env.sh && rcb backup > /proc/1/fd/1
+10 2 * * * source /env.sh && /backup.sh > /proc/1/fd/1