From c5a3e2e37683a9ed5e99633a6ae21768a6e59fe3 Mon Sep 17 00:00:00 2001
From: Daniel Ramp <12480131+DanielRamp@users.noreply.github.com>
Date: Sun, 18 Jul 2021 01:44:18 +0200
Subject: [PATCH] Cache spiget version resolution (#978)

---
 start-spiget | 70 +++++++++++++++++++++++++++++++++++++++-------------
 1 file changed, 53 insertions(+), 17 deletions(-)

diff --git a/start-spiget b/start-spiget
index 6773d800..fe957331 100644
--- a/start-spiget
+++ b/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 '.name' $versionfile)
+      newVersion=$(jq '.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
 
 }