feat: add minecraft backup method

Minecraft server can now be backed up using the restic-compose-backup.minecraft flag

.gitignore

@@ -20,6 +20,7 @@ venv
 restic_data/
 restic_cache/
 alerts.env
+minecraft/
 
 # build
 build/

docker-compose.yaml

@@ -67,6 +67,17 @@ services:
     volumes:
       - pgdata:/var/lib/postgresql/data
 
+  minecraft:
+    image: itzg/minecraft-server
+    labels:
+      restic-compose-backup.minecraft: true
+      restic-compose-backup.volumes.include: "minecraft"
+    environment:
+      - RCON_PASSWORD=minecraft
+      - EULA=TRUE
+    volumes:
+      - ./minecraft:/data
+
 volumes:
   mysqldata:
   mariadbdata:

src/Dockerfile

@@ -37,8 +37,5 @@ ENV XDG_CACHE_HOME=/cache
 
 # end install
 
-ADD backup.sh /backup.sh
-RUN chmod +x /backup.sh
-
 ENTRYPOINT []
 CMD ["./entrypoint.sh"]

src/backup.sh

@@ -1,158 +0,0 @@
-#!/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

src/crontab

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

src/restic_compose_backup/cli.py

@@ -9,7 +9,7 @@ from restic_compose_backup import (
     restic,
 )
 from restic_compose_backup.config import Config
-from restic_compose_backup.containers import RunningContainers
+from restic_compose_backup.containers import RunningContainers, Container
 from restic_compose_backup import cron, utils
 
 logger = logging.getLogger(__name__)
@@ -94,6 +94,21 @@ def status(config, containers):
     for container in backup_containers:
         logger.info('service: %s', container.service_name)
 
+        if container.minecraft_backup_enabled:
+            instance = container.instance
+            ping = instance.ping()
+            logger.info(
+                ' - %s (is_ready=%s):',
+                instance.container_type,
+                ping == 0
+            )
+            for mount in container.filter_mounts():
+                logger.info(
+                    '   - volume: %s -> %s',
+                    mount.source,
+                    container.get_volume_backup_destination(mount, '/minecraft'),
+                )
+
         if container.volume_backup_enabled:
             for mount in container.filter_mounts():
                 logger.info(

src/restic_compose_backup/config.py

@@ -2,8 +2,8 @@ import os
 
 
 class Config:
-    default_backup_command = ". /env.sh && /backup.sh > /proc/1/fd/1 2>&1"
-    default_crontab_schedule = "0 */4 * * *"
+    default_backup_command = "source /env.sh && rcb backup > /proc/1/fd/1"
+    default_crontab_schedule = "10 2 * * *"
 
     """Bag for config values"""
     def __init__(self, check=True):

src/restic_compose_backup/containers.py

@@ -144,6 +144,7 @@ class Container:
         return any([
             self.volume_backup_enabled,
             self.database_backup_enabled,
+            self.minecraft_backup_enabled
         ])
 
     @property
@@ -206,7 +207,7 @@ class Container:
         exclude_bind_mounts = utils.is_true(config.exclude_bind_mounts)
         mounts = list(filter(lambda m: not exclude_bind_mounts or m.type == "volume", self._mounts))
 
-        if not self.volume_backup_enabled:
+        if not self.volume_backup_enabled and not self.minecraft_backup_enabled:
             return filtered
 
         if self._include:

src/restic_compose_backup/containers_minecraft.py

@@ -1,3 +1,6 @@
+import os
+import logging
+
 from pathlib import Path
 
 from restic_compose_backup.containers import Container
@@ -9,6 +12,8 @@ from restic_compose_backup import (
 )
 from restic_compose_backup import utils
 
+logger = logging.getLogger(__name__)
+
 
 class MinecraftContainer(Container):
     container_type = 'minecraft'
@@ -21,16 +26,30 @@ class MinecraftContainer(Container):
             'port': self.get_config_env('RCON_PORT'),
         }
 
+    def prepare_mc_backup(self) -> bool:
+        creds = self.get_credentials()
+
+        with utils.environment('RCON_PASSWORD', creds['password']):
+            rcon.save_off(creds['host'], creds['port'])
+            rcon.save_all(creds['host'], creds['port'])
+            rcon.sync(creds['host'], creds['port'])
+            return True
+
     def ping(self) -> bool:
         """Check the availability of the service"""
         creds = self.get_credentials()
 
-        logger.debug("[rcon-cli] checking if minecraft server %s is online...", self.service_name)
-        with utils.environment('RCON_PASSWORD', creds['password']):
-            return rcon.is_online(
-                creds['host'],
-                creds['port']
-            )
+        try:
+            logger.debug("[rcon-cli] checking if minecraft server %s is online...", self.service_name)
+            with utils.environment('RCON_PASSWORD', creds['password']):
+                return rcon.is_online(
+                    creds['host'],
+                    creds['port']
+                )
+        except Exception as ex:
+            logger.error('[rcon-cli] unable to contact minecraft server %s', self.service_name)
+            logger.exception(ex)
+            return 1
 
     def backup(self) -> bool:
         config = Config()
@@ -40,15 +59,16 @@ class MinecraftContainer(Container):
         with utils.environment('RCON_PASSWORD', creds['password']):
             try:
                 # turn off auto-save and sync all data to the disk before backing up worlds
-                prepare_mc_backup()
-                for mount in container.filter_mounts():
-                    backup_data = container.get_volume_backup_destination(mount, '/volumes')
-                        logger.info('Backing up %s', mount.source)
-                        vol_result = restic.backup_files(config.repository, source=backup_data)
-                        logger.debug('Minecraft backup exit code: %s', vol_result)
-                        if vol_result != 0:
-                            logger.error('Minecraft backup exited with non-zero code: %s', vol_result)
-                            errors = True
+                self.prepare_mc_backup()
+
+                for mount in self.filter_mounts():
+                    backup_data = self.get_volume_backup_destination(mount, '/minecraft')
+                    logger.info('Backing up %s', mount.source)
+                    vol_result = restic.backup_files(config.repository, source=backup_data)
+                    logger.debug('Minecraft backup exit code: %s', vol_result)
+                    if vol_result != 0:
+                        logger.error('Minecraft backup exited with non-zero code: %s', vol_result)
+                        errors = True
             except Exception as ex:
                 logger.error('Exception raised during minecraft backup')
                 logger.exception(ex)
@@ -57,13 +77,4 @@ class MinecraftContainer(Container):
             # always always turn saving back on
             rcon.save_on(creds['host'], creds['port'])
 
-        return errors
-
-    
-    def prepare_mc_backup():
-        creds = self.get_credentials()
-
-        with utils.environment('RCON_PASSWORD', creds['password']):
-            rcon.save_off(creds['host'], creds['port'])
-            rcon.save_all(creds['host'], creds['port'])
-            rcon.sync(creds['host'], creds['port'])
+        return errors

src/restic_compose_backup/rcon.py

@@ -8,25 +8,26 @@ from restic_compose_backup import (
     commands,
     containers
 )
+from restic_compose_backup import utils
 
 logger = logging.getLogger(__name__)
 
 def rcon_cli(host, port, cmd: str) -> int:
     exit_code = commands.run([
         "rcon-cli",
-        f"--host {host}",
-        f"--port {port}",
+        f"--host={host}",
+        f"--port={port}",
         cmd
     ])
 
     if exit_code != 0:
-        raise RconException("rcon-cli %s exited with a non-zero exit code: %s", cmd, exit_code)
+        raise RconException(f"rcon-cli {cmd} exited with a non-zero exit code: {exit_code}")
 
     return exit_code
 
 def is_online(host, port) -> int:
     """Check if rcon can be reached"""
-    return rcon_cli(host, port, "version")
+    return rcon_cli(host, port, "help")
 
 def save_off(host, port) -> int:
     """Turn saving off"""