Added support for Java 7

Co-authored-by: Chris Fowles <chris.fowles@plenti.com.au>

.github/workflows/build-multiarch.yml

@@ -5,6 +5,7 @@ on:
       - master
       - "*-multiarch"
       - "multiarch*"
+      - java7
       - java8-openj9
       - java11*
       - java16*
@@ -66,7 +67,7 @@ jobs:
         uses: docker/build-push-action@v2.6.1
         with:
           context: .
-          platforms: linux/amd64
+          platforms: linux/amd64,linux/arm/v7
           push: ${{ github.event_name != 'pull_request' }}
           tags: ${{ steps.meta.outputs.tags }}
           # ensure latest base image is used

Dockerfile

@@ -1,4 +1,4 @@
-FROM adoptopenjdk:8-jre-openj9
+FROM openjdk:7-jre
 
 LABEL org.opencontainers.image.authors="Geoff Bourne <itzgeoff@gmail.com>"
 
@@ -6,7 +6,6 @@ RUN apt-get update \
   && DEBIAN_FRONTEND=noninteractive \
   apt-get install -y \
     imagemagick \
-    gosu \
     sudo \
     net-tools \
     curl wget \
@@ -22,6 +21,42 @@ RUN apt-get update \
     ttf-dejavu \
     && apt-get clean
 
+# Procedure from https://github.com/tianon/gosu/blob/master/INSTALL.md#from-debian
+ENV GOSU_VERSION 1.14
+RUN set -eux; \
+# save list of currently installed packages for later so we can clean up
+	savedAptMark="$(apt-mark showmanual)"; \
+	apt-get update; \
+	apt-get install -y --no-install-recommends ca-certificates wget; \
+	if ! command -v gpg; then \
+		apt-get install -y --no-install-recommends gnupg2 dirmngr; \
+	elif gpg --version | grep -q '^gpg (GnuPG) 1\.'; then \
+# "This package provides support for HKPS keyservers." (GnuPG 1.x only)
+		apt-get install -y --no-install-recommends gnupg-curl; \
+	fi; \
+	rm -rf /var/lib/apt/lists/*; \
+	\
+	dpkgArch="$(dpkg --print-architecture | awk -F- '{ print $NF }')"; \
+	wget -O /usr/local/bin/gosu "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch"; \
+	wget -O /usr/local/bin/gosu.asc "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch.asc"; \
+	\
+# verify the signature
+	export GNUPGHOME="$(mktemp -d)"; \
+	gpg --batch --keyserver hkps://keys.openpgp.org --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4; \
+	gpg --batch --verify /usr/local/bin/gosu.asc /usr/local/bin/gosu; \
+	command -v gpgconf && gpgconf --kill all || :; \
+	rm -rf "$GNUPGHOME" /usr/local/bin/gosu.asc; \
+	\
+# clean up fetch dependencies
+	apt-mark auto '.*' > /dev/null; \
+	[ -z "$savedAptMark" ] || apt-mark manual $savedAptMark; \
+	apt-get purge -y --auto-remove -o APT::AutoRemove::RecommendsImportant=false; \
+	\
+	chmod +x /usr/local/bin/gosu; \
+# verify that the binary works
+	gosu --version; \
+	gosu nobody true
+
 RUN addgroup --gid 1000 minecraft \
   && adduser --system --shell /bin/false --uid 1000 --ingroup minecraft --home /data minecraft
 
@@ -52,7 +87,7 @@ RUN easy-add --var os=${TARGETOS} --var arch=${TARGETARCH}${TARGETVARIANT} \
  --from https://github.com/itzg/{{.app}}/releases/download/{{.version}}/{{.app}}_{{.version}}_{{.os}}_{{.arch}}.tar.gz
 
 RUN easy-add --var os=${TARGETOS} --var arch=${TARGETARCH}${TARGETVARIANT} \
- --var version=1.5.0 --var app=mc-server-runner --file {{.app}} \
+ --var version=1.6.0 --var app=mc-server-runner --file {{.app}} \
  --from https://github.com/itzg/{{.app}}/releases/download/{{.version}}/{{.app}}_{{.version}}_{{.os}}_{{.arch}}.tar.gz
 
 RUN easy-add --var os=${TARGETOS} --var arch=${TARGETARCH}${TARGETVARIANT} \

README.md

@@ -13,30 +13,11 @@ To simply use the latest stable version, run
 
     docker run -d -it -p 25565:25565 -e EULA=TRUE itzg/minecraft-server
 
-where the standard server port, 25565, will be exposed on your host machine.
+where, in this case, the standard server port 25565, will be exposed on your host machine.
 
-If you want to serve up multiple Minecraft servers or just use an alternate port,
-change the host-side port mapping such as
+> If you plan on running a server for a longer amount of time it is highly recommended using a management layer such as [Docker Compose](#using-docker-compose) or [Kubernetes](#deployment-templates-and-examples) to allow for incremental reconfiguration and image upgrades.
 
-    ... -p 25566:25565 ...
-
-will serve your Minecraft server on your host's port 25566 since the `-p` syntax is
-`host-port`:`container-port`.
-
-Speaking of multiple servers, it's handy to give your containers explicit names using `--name`, such as naming this one "mc"
-
-    ... --name mc itzg/minecraft-server
-
-With that you can easily view the logs, stop, or re-start the container:
-
-    docker logs -f mc
-        ( Ctrl-C to exit logs action )
-
-    docker stop mc
-
-    docker start mc
-
-> Be sure to always include `-e EULA=TRUE` in your commands, as Mojang/Microsoft requires EULA acceptance.
+> Be sure to always include `-e EULA=TRUE` in your commands and container definitions, as Mojang/Microsoft requires EULA acceptance.
 
 By default, the container will download the latest version of the "vanilla" [Minecraft: Java Edition server](https://www.minecraft.net/en-us/download/server) provided by Mojang. The [`VERSION`](#versions) and the [`TYPE`](#server-types) can be configured to create many variations of desired Minecraft server. 
 
@@ -71,13 +52,14 @@ By default, the container will download the latest version of the "vanilla" [Min
       * [Running an Canyon server](#running-an-canyon-server)
       * [Running a SpongeVanilla server](#running-a-spongevanilla-server)
       * [Running a Fabric Server](#running-a-fabric-server)
+      * [Running a Limbo server](#running-a-limbo-server)
    * [Running a server with a Feed the Beast modpack](#running-a-server-with-a-feed-the-beast-modpack)
       * [Environment Variables:](#environment-variables)
       * [Upgrading](#upgrading)
       * [Example](#example)
    * [Running a server with a CurseForge modpack](#running-a-server-with-a-curseforge-modpack)
-         * [Modpack data directory](#modpack-data-directory)
-         * [Buggy start scripts](#buggy-start-scripts)
+      * [Modpack data directory](#modpack-data-directory)
+      * [Buggy start scripts](#buggy-start-scripts)
       * [Fixing "unable to launch forgemodloader"](#fixing-unable-to-launch-forgemodloader)
    * [Working with mods and plugins](#working-with-mods-and-plugins)
       * [Optional plugins, mods, and config attach points](#optional-plugins-mods-and-config-attach-points)
@@ -131,6 +113,7 @@ By default, the container will download the latest version of the "vanilla" [Min
       * [Memory Limit](#memory-limit)
       * [JVM Options](#jvm-options)
       * [Interactive and Color Console](#interactive-and-color-console)
+      * [Server Shutdown Options](#server-shutdown-options)
       * [OpenJ9 Specific Options](#openj9-specific-options)
       * [Enabling rolling logs](#enabling-rolling-logs)
    * [Timezone Configuration](#timezone-configuration)
@@ -145,7 +128,7 @@ By default, the container will download the latest version of the "vanilla" [Min
       * [Enabling Autopause](#enabling-autopause)
    * [Running on RaspberryPi](#running-on-raspberrypi)
 
-<!-- Added by: runner, at: Thu Jul 15 13:34:00 UTC 2021 -->
+<!-- Added by: runner, at: Sun Aug 15 17:44:45 UTC 2021 -->
 
 <!--te-->
 
@@ -489,7 +472,9 @@ A [Magma](https://magmafoundation.org/) server, which is a combination of Forge
 
     -e TYPE=MAGMA
 
-> **NOTE** there are limited base versions supported, so you will also need to  set `VERSION`, such as "1.12.2"
+By default, the "stable" channel is used, but you can set `MAGMA_CHANNEL` to "dev" to access dev channel versions.
+
+> **NOTE** there are limited base versions supported, so you will also need to  set `VERSION`, such as "1.12.2", "1.16.5", etc.
 
 
 ### Running a Mohist server
@@ -569,6 +554,20 @@ docker run -d -v /path/on/host:/data ... \
 
 In order to add mods, you have two options:
 
+### Running a Limbo server
+
+A [Limbo](https://github.com/LOOHP/Limbo) server can be run by setting `TYPE` to `LIMBO`.
+
+Configuration options with defaults:
+
+- `LIMBO_BUILD`=LATEST
+
+  The `VERSION` will be ignored so locate the appropriate value from [here](https://ci.loohpjames.com/job/Limbo/) to match the version expected by clients.
+
+- `FORCE_REDOWNLOAD`=false
+- `LIMBO_SCHEMA_FILENAME`=default.schem
+- `LEVEL`="Default;${LIMBO_SCHEMA_FILENAME}"
+
 ## Running a server with a Feed the Beast modpack
 
 > **NOTE** requires one of the Debian based images listed in [the Java versions section](#running-minecraft-server-on-different-java-version).
@@ -620,13 +619,13 @@ The following example uses `/modpacks` as the container path as the pre-download
         -e CF_SERVER_MOD=/modpacks/SkyFactory_4_Server_4.1.0.zip \
         -p 25565:25565 -e EULA=TRUE --name mc itzg/minecraft-server
 
-#### Modpack data directory
+### Modpack data directory
 
 By default, CurseForge modpacks are expanded into the sub-directory `/data/FeedTheBeast` and executed from there. (The default location was chosen for legacy reasons, when Curse and FTB were maintained together.)
 
 The directory can be changed by setting `CF_BASE_DIR`, such as `-e CF_BASE_DIR=/data`.
 
-#### Buggy start scripts
+### Buggy start scripts
 
 Some modpacks have buggy or overly complex start scripts. You can avoid using the bundled start script and use this image's standard server-starting logic by adding `-e USE_MODPACK_START_SCRIPT=false`.
 
@@ -1227,6 +1226,12 @@ If you would like to `docker attach` to the Minecraft server console with color
 > 
 > Make to enable stdin and tty with `-it` when using `docker run` or `stdin_open: true` and `tty: true` when using docker compose.
 
+### Server Shutdown Options
+
+To allow time for players to finish what they're doing during a graceful server shutdown, set `STOP_SERVER_ANNOUNCE_DELAY` to a number of seconds to delay after an announcement is posted by the server.
+
+> **NOTE** be sure to adjust Docker's shutdown timeout accordingly, such as using [the -t option on docker-compose down](https://docs.docker.com/compose/reference/down/).
+
 ### OpenJ9 Specific Options
 
 The openj9 image tags include specific variables to simplify configuration:

start-configuration

@@ -98,6 +98,14 @@ case "${TYPE^^}" in
   ;;
 
   FORGE)
+    if versionLessThan 1.17; then
+    log "**********************************************************************"
+    log "WARNING: The image tag itzg/minecraft-server:java8 is recommended"
+    log "         since some mods require Java 8"
+    log "         Exception traces reporting ClassCastException: class jdk.internal.loader.ClassLoaders\$AppClassLoader"
+    log "         can be fixed with java8"
+    log "**********************************************************************"
+    fi
     exec ${SCRIPTS:-/}start-deployForge "$@"
   ;;
 
@@ -110,6 +118,12 @@ case "${TYPE^^}" in
   ;;
 
   FTB|CURSEFORGE)
+    log "**********************************************************************"
+    log "WARNING: The image tag itzg/minecraft-server:java8 is recommended"
+    log "         since some mods require Java 8"
+    log "         Exception traces reporting ClassCastException: class jdk.internal.loader.ClassLoaders\$AppClassLoader"
+    log "         can be fixed with java8"
+    log "**********************************************************************"
     exec ${SCRIPTS:-/}start-deployCF "$@"
   ;;
 
@@ -157,11 +171,15 @@ case "${TYPE^^}" in
     exec ${SCRIPTS:-/}start-deployCanyon "$@"
   ;;
 
+  LIMBO)
+    exec ${SCRIPTS:-/}start-deployLimbo "$@"
+  ;;
+
   *)
       log "Invalid type: '$TYPE'"
       log "Must be: VANILLA, FORGE, BUKKIT, SPIGOT, PAPER, FTBA (multiarch-only),"
       log "         CURSE_INSTANCE, CURSEFORGE, SPONGEVANILLA, TUINITY, PURPUR"
-      log "         CUSTOM, MAGMA, MOHIST, CATSERVER, YATOPIA, AIRPLANE, CANYON"
+      log "         CUSTOM, MAGMA, MOHIST, CATSERVER, YATOPIA, AIRPLANE, CANYON, LIMBO"
       exit 1
   ;;
 

start-deployAirplane

@@ -11,6 +11,7 @@ if [ "${VERSION}" != "LATEST" ] && [ "${VERSION}" != "1.16" ] && [ "${VERSION}"
 fi
 
 : ${AIRPLANE_BUILD:=lastSuccessfulBuild}
+: ${AIRPLANE_TYPE:=airplane}
 
 if  [ "${VERSION}" = "LATEST" ] || [ "${VERSION}" = "1.17" ]; then
   AIRPLANE_BRANCH="1.17"
@@ -22,10 +23,12 @@ fi
 
 if [ "${VERSION}" = "PURPUR" ]; then
   AIRPLANE_BRANCH="Purpur-1.17"
+  AIRPLANE_TYPE="airplanepurpur"
 fi
 
 if [ "${VERSION}" = "PURPUR-1.16" ]; then
   AIRPLANE_BRANCH="Purpur-1.16"
+  AIRPLANE_TYPE="airplanepurpur"
 fi
 
 log "Using Airplane-${AIRPLANE_BRANCH} branch"
@@ -33,7 +36,7 @@ log "Using Airplane-${AIRPLANE_BRANCH} branch"
 export SERVER=airplane-${AIRPLANE_BRANCH}-${AIRPLANE_BUILD}.jar
 
 if [ ! -f "$SERVER" ] || isTrue "${FORCE_REDOWNLOAD:-false}"; then
-    downloadUrl="https://ci.tivy.ca/job/Airplane-${AIRPLANE_BRANCH}/${AIRPLANE_BUILD}/artifact/launcher-airplane.jar"
+    downloadUrl="https://ci.tivy.ca/job/Airplane-${AIRPLANE_BRANCH}/${AIRPLANE_BUILD}/artifact/launcher-${AIRPLANE_TYPE}.jar"
     log "Downloading Airplane from $downloadUrl ..."
     curl -fsSL -o "$SERVER" "$downloadUrl"
     if [ ! -f "$SERVER" ]; then

start-deployFTBA

@@ -30,7 +30,13 @@ if ! [ -f "${ftbInstallMarker}" ] || [ $(cat "${ftbInstallMarker}") != "${FTB_MO
   ftbInstaller=/data/ftb-installer
   if ! [[ -f "${ftbInstaller}" ]]; then
     log "Downloading FTB installer"
-    curl -fsSL https://api.modpacks.ch/public/modpack/1/1/server/linux -o "${ftbInstaller}"
+    if [ "$(uname -m)" == "aarch64" ]; then
+      log "Downloading ARM installer"
+      curl -fsSL https://api.modpacks.ch/public/modpack/1/1/server/arm/linux -o "${ftbInstaller}"
+    else
+      log "Downloading x86 installer"
+      curl -fsSL https://api.modpacks.ch/public/modpack/1/1/server/linux -o "${ftbInstaller}"
+    fi
     chmod +x "${ftbInstaller}"
   fi
 

start-deployForge

@@ -1,7 +1,6 @@
 #!/bin/bash
 
 . ${SCRIPTS:-/}start-utils
-export TYPE=FORGE
 : ${FORGEVERSION:=RECOMMENDED}
 isDebugging && set -x
 
@@ -47,7 +46,7 @@ elif [[ ! -e $FORGE_INSTALLER ]]; then
   log "ERROR: the given Forge installer doesn't exist : $FORGE_INSTALLER"
   exit 2
 else
-  shortForgeVersion=$VANILLA_VERSION-custom
+  shortForgeVersion=$VANILLA_VERSION-${FORGE_INSTALLER_CUSTOM_VERSION:-custom}
 fi
 
 installMarker="/data/.forge-installed-$shortForgeVersion"

start-deployLimbo

@@ -0,0 +1,57 @@
+#!/bin/bash
+set -euo pipefail
+IFS=$'\n\t'
+
+. ${SCRIPTS:-/}start-utils
+isDebugging && set -x
+
+: ${LIMBO_BUILD:=LATEST}
+: ${FORCE_REDOWNLOAD:=false}
+: ${LIMBO_SCHEMA_FILENAME:=default.schem}
+: ${LEVEL:=Default;${LIMBO_SCHEMA_FILENAME}}
+
+if [[ ${LIMBO_BUILD^^} == LATEST ]]; then
+  LIMBO_BUILD=lastStableBuild
+fi
+
+baseUrl="https://ci.loohpjames.com/job/Limbo/${LIMBO_BUILD}"
+buildInfoUrl="${baseUrl}/api/json"
+buildJson=$(curl -fsSL "${buildInfoUrl}")
+if [ $? != 0 ]; then
+  log "ERROR failed to get build info from ${buildInfoUrl} (status=$?)"
+  exit 1
+fi
+
+PURPUR_BUILD=$(jq -r '.number' <<<${buildJson})
+artifactPath=$(jq -r '.artifacts[] | select(.fileName|test("^Limbo-")) | .relativePath' <<<${buildJson})
+defaultSchemaPath=$(jq -r '.artifacts[] | select(.fileName|test(".*\\.schem")) | .relativePath' <<<${buildJson})
+
+export SERVER="purpur-${PURPUR_BUILD}.jar"
+
+if [ ! -f "$SERVER" ] || isTrue "$FORCE_REDOWNLOAD"; then
+    downloadUrl="${baseUrl}/artifact/${artifactPath}"
+    log "Downloading Limbo from $downloadUrl ..."
+    if ! curl -fsSL -o "$SERVER" "$downloadUrl"; then
+      log "ERROR: failed to download from $downloadUrl (status=$?)"
+      exit 3
+    fi
+
+fi
+
+if [ ! -f "${LIMBO_SCHEMA_FILENAME}" ]; then
+  log "Downloading default schem file"
+  if ! curl -o "${LIMBO_SCHEMA_FILENAME}" -fsSL "${baseUrl}/artifact/${defaultSchemaPath}"; then
+      log "ERROR: failed to download schema file $baseUrl (status=$?)"
+      exit 3
+  fi
+fi
+
+if [[ ${LEVEL} != "*;*" ]]; then
+  LEVEL="${LEVEL};${LIMBO_SCHEMA_FILENAME}"
+fi
+export LEVEL
+
+export SKIP_LOG4J_CONFIG=true
+
+# Continue to Final Setup
+exec ${SCRIPTS:-/}start-finalSetupWorld $@

start-deployMagma

@@ -1,18 +1,93 @@
 #!/bin/bash
 
 . ${SCRIPTS:-/}start-utils
+export SKIP_LOG4J_CONFIG=true
 
-export SERVER="/data/magma-server-${VANILLA_VERSION}.jar"
+isDebugging && set -x
 
-# Always download since new updates of each base version are published frequently
-if ! curl -o /data/magma-server-${VANILLA_VERSION}.jar -fsSL \
-  https://api.magmafoundation.org/api/resources/Magma/${VANILLA_VERSION}/stable/latest/download; then
-  log "ERROR unable to download version ${VANILLA_VERSION} of Magma"
-  log "      Check https://magmafoundation.org/ for available versions"
+: ${VANILLA_VERSION?}
+# stable, dev
+: ${MAGMA_CHANNEL:=stable}
+
+
+magmaDownloadServer() {
+  url=${1?}
+  tagName=${2?}
+  markerFile=${3?}
+
+  export SERVER="/data/magma-server-${VANILLA_VERSION}.jar"
+
+  log "Downloading Magma server file for ${VANILLA_VERSION} @ ${tagName}"
+  if ! curl -o /data/magma-server-${VANILLA_VERSION}.jar -fsSL "$url"; then
+    log "ERROR failed to download Magma server from $url (status=$?)"
+    exit 1
+  fi
+
+  echo -n "$SERVER" > "$markerFile"
+}
+
+magmaHandleInstaller() {
+  url=${1?}
+  tagName=${2?}
+  markerFile=${3?}
+
+  installerFile="magma-installer-${VANILLA_VERSION}-${tagName}.jar"
+  log "Downloading Magma installer file for ${VANILLA_VERSION} @ ${tagName}"
+  if ! curl -o "$installerFile" -fsSL "$url"; then
+    log "ERROR failed to download Magma installer from $url (status=$?)"
+    exit 1
+  fi
+
+  echo "forge" > "$markerFile"
+
+  export FORGE_INSTALLER="$installerFile"
+  export FORGE_INSTALLER_CUSTOM_VERSION="$tagName"
+
+  # now hand off the rest to forge
+  exec ${SCRIPTS:-/}start-deployForge "$@"
+}
+
+latestMeta=$(curl -fsSL https://api.magmafoundation.org/api/resources/Magma/${VANILLA_VERSION}/${MAGMA_CHANNEL}/latest || exit $?)
+if [ $? != 0 ]; then
+  log "ERROR failed to locate latest Magma info for ${VANILLA_VERSION} in channel ${MAGMA_CHANNEL} (error=$?)"
   exit 1
 fi
 
-export SKIP_LOG4J_CONFIG=true
+tagName=$(echo "${latestMeta}" | jq -r '.tag_name')
+markerFile=".magma-installed-${VANILLA_VERSION}-${tagName}"
+if [ -f "${markerFile}" ]; then
+  installedTagName=$(cat "${markerFile}")
+fi
+
+if [ ! -f "${markerFile}" ]; then
+
+  if versionLessThan 1.16; then
+    assetType=server
+  else
+    assetType=installer
+  fi
+
+  assetUrl=$(echo "${latestMeta}" | jq -r ".assets | .[].browser_download_url | select(test(\"${assetType}\"))")
+  if [ $? != 0 ] || [ -z "$assetUrl" ]; then
+    log "ERROR failed to extract ${assetType} asset type for ${VANILLA_VERSION} in channel ${MAGMA_CHANNEL}"
+    exit 1
+  fi
+
+  if [[ ${assetType} = server ]]; then
+    magmaDownloadServer "$assetUrl" "$tagName" "$markerFile"
+  else
+    magmaHandleInstaller "$assetUrl" "$tagName" "$markerFile"
+  fi
+else
+  export SERVER=$(cat "${markerFile}")
+
+  if [[ $SERVER == "forge" ]]; then
+    export FORGE_INSTALLER="magma-installer-${VANILLA_VERSION}-${tagName}.jar"
+    export FORGE_INSTALLER_CUSTOM_VERSION="$tagName"
+    # now hand off the rest to forge
+    exec ${SCRIPTS:-/}start-deployForge "$@"
+  fi
+fi
 
 # Continue to Final Setup
 exec ${SCRIPTS:-/}start-finalSetupWorld $@

start-minecraftFinalSetup

@@ -173,6 +173,10 @@ function copyFilesForCurseForge() {
 }
 
 mcServerRunnerArgs="--stop-duration ${STOP_DURATION:-60}s"
+if [[ ${STOP_SERVER_ANNOUNCE_DELAY} ]]; then
+  mcServerRunnerArgs="${mcServerRunnerArgs} --stop-server-announce-delay ${STOP_SERVER_ANNOUNCE_DELAY}s"
+fi
+
 if [[ ${TYPE} == "CURSE_INSTANCE" ]]; then
     if isTrue ${DEBUG_EXEC}; then
       set -x
@@ -225,6 +229,10 @@ EOF
   else
     exec mc-server-runner ${mcServerRunnerArgs} "${finalArgs[@]}"
   fi
+elif [[ -x run.sh ]]; then
+  log "Using Forge supplied run.sh script..."
+  echo $JVM_XX_OPTS $JVM_OPTS $expandedDOpts > user_jvm_args.txt
+  exec mc-server-runner ${mcServerRunnerArgs} --shell bash run.sh
 else
   # If we have a bootstrap.txt file... feed that in to the server stdin
   if [ -f /data/bootstrap.txt ]; then

start-spiget

@@ -6,6 +6,7 @@ IFS=$'\n\t'
 handleDebugMode
 
 : ${SPIGET_RESOURCES:=}
+: ${SPIGET_DOWNLOAD_TOLERANCE:=5} # in minutes
 
 containsJars() {
   file=${1?}
@@ -28,26 +29,61 @@ getResourceFromSpiget() {
 
   mkdir -p /data/plugins
 
-  if [ -f /data/plugins/.${resource} ]; then
-    log "Resource '${resource}' already downloaded"
-  else
-    tmpfile="/tmp/${resource}.zip"
-    url="https://api.spiget.org/v2/resources/${resource}/download"
-    if ! curl -o "${tmpfile}" -fsSL -H "User-Agent: itzg/minecraft-server" "${extraCurlArgs[@]}" "${url}"; then
-      log "ERROR failed to download resource '${resource}' from ${url}"
-      exit 2
-    fi
+  versionfile="/data/plugins/.${resource}-version.json"
+  versionfileNew="/tmp/.${resource}-version.json"
 
-    if containsJars "${tmpfile}"; then
-      log "Extracting contents of resource ${resource} into plugins"
-      unzip -o -q -d /data/plugins "${tmpfile}"
-      touch "/data/plugins/.${resource}"
-      rm "${tmpfile}"
+  if [ -f "$versionfile" ]; then
+    if [[ -n $(find "$versionfile" -mmin +${SPIGET_DOWNLOAD_TOLERANCE}) ]]; then
+      urlVersion="https://api.spiget.org/v2/resources/${resource}/versions/latest"
+      if ! curl -o "${versionfileNew}" -fsSL -H "User-Agent: itzg/minecraft-server" "${extraCurlArgs[@]}" "${urlVersion}"; then
+        log "ERROR failed to download resource version meta data '${resource}' from ${urlVersion}"
+        exit 2
+      fi
+
+      installedVersion=$(jq -r '.name' $versionfile)
+      newVersion=$(jq -r '.name' $versionfileNew)
+      
+      if [ "$installedVersion" = "$newVersion" ]; then
+        log "resource '${resource}' not downloaded because installed version '${installedVersion}' already up to date ('${newVersion}')"
+        mv "${versionfileNew}" "${versionfile}"
+      else
+        if downloadResourceFromSpiget "${resource}"; then
+          mv "${versionfileNew}" "${versionfile}"
+        fi
+      fi
     else
-      log "Moving resource ${resource} into plugins"
-      mv "${tmpfile}" "/data/plugins/${resource}.jar"
-      touch "/data/plugins/.${resource}"
+      log "resource '${resource}' not checked because version meta file newer than '${SPIGET_DOWNLOAD_TOLERANCE}' minutes"
     fi
+  else
+    if downloadResourceFromSpiget "${resource}"; then
+      urlVersion="https://api.spiget.org/v2/resources/${resource}/versions/latest"
+      if ! curl -o "${versionfileNew}" -fsSL -H "User-Agent: itzg/minecraft-server" "${extraCurlArgs[@]}" "${urlVersion}"; then
+        log "ERROR failed to download resource version meta data '${resource}' from ${urlVersion}"
+        exit 2
+      fi
+      mv "${versionfileNew}" "${versionfile}"
+    fi
+  fi
+
+}
+
+downloadResourceFromSpiget() {
+  resource=${1?}
+
+  tmpfile="/tmp/${resource}.zip"
+  url="https://api.spiget.org/v2/resources/${resource}/download"
+  if ! curl -o "${tmpfile}" -fsSL -H "User-Agent: itzg/minecraft-server" "${extraCurlArgs[@]}" "${url}"; then
+    log "ERROR failed to download resource '${resource}' from ${url}"
+    exit 2
+  fi
+
+  if containsJars "${tmpfile}"; then
+    log "Extracting contents of resource ${resource} into plugins"
+    unzip -o -q -d /data/plugins "${tmpfile}"
+    rm "${tmpfile}"
+  else
+    log "Moving resource ${resource} into plugins"
+    mv "${tmpfile}" "/data/plugins/${resource}.jar"
   fi
 
 }