Fix duplicate mod error with Space Age DLC mods (#576)

Skip downloading built-in DLC mods (elevated-rails, quality, space-age) when UPDATE_MODS_ON_START is enabled. These mods are included with the Space Age DLC and attempting to download them separately causes "Duplicate mod" errors.

- Modified update-mods.sh to skip DLC built-in mods during updates
- Added documentation note explaining the automatic handling of DLC mods

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

README.md

@@ -6,8 +6,17 @@
 [中文](./README_zh_CN.md)
 
 <!-- start autogeneration tags -->
-* `latest, 2.0.58`
+* `latest, 2.0.59`
 * `2, 2.0, 2.0.55, stable, stable-2.0.55`
+* `2.0.58`
+* `stable-1.1.110, 1, 1.1, 1.1.110`
+* `1.0.0, 1.0`
+* `0.17.79, 0.17`
+* `0.16.51, 0.16`
+* `0.15.40, 0.15`
+* `0.14.23, 0.14`
+* `0.13.20, 0.13`
+* `0.12.35, 0.12`
 <!-- end autogeneration tags -->
 
 ## Tag descriptions
@@ -175,6 +184,8 @@ Copy mods into the mods folder and restart the server.
 
 As of 0.17 a new environment variable was added ``UPDATE_MODS_ON_START`` which if set to ``true`` will cause the mods get to updated on server start. If set a valid [Factorio Username and Token](https://www.factorio.com/profile) must be supplied or else the server will not start. They can either be set as docker secrets, environment variables, or pulled from the server-settings.json file.
 
+**Note:** When using the Space Age DLC, the built-in mods (`elevated-rails`, `quality`, and `space-age`) are automatically skipped during mod updates to prevent conflicts. These mods are included with the DLC and should not be downloaded separately.
+
 ### Scenarios
 
 If you want to launch a scenario from a clean start (not from a saved map) you'll need to start the docker image from an alternate entrypoint. To do this, use the example entrypoint file stored in the /factorio/entrypoints directory in the volume, and launch the image with the following syntax. Note that this is the normal syntax with the addition of the --entrypoint setting AND the additional argument at the end, which is the name of the Scenario in the Scenarios folder.

buildinfo.json

@@ -356,8 +356,14 @@
   "2.0.58": {
     "sha256": "be82e1aeba4169420e1b00c12a3e00ec2309a41327f9d6c335feec27bbc885e6",
     "tags": [
-      "latest",
       "2.0.58"
     ]
+  },
+  "2.0.59": {
+    "sha256": "fdc467bf80e3611d6dd08c79492228ffec53f3fe914f24d793cac254d9353ff7",
+    "tags": [
+      "latest",
+      "2.0.59"
+    ]
   }
 }

docker/files/update-mods.sh

@@ -23,24 +23,33 @@ print_failure()
   echo "$1"
 }
 
-# Checks game version vs version in mod.
-# Returns 0 if major version differs or mod minor version is less than game version, 1 if ok
+# Checks if the current game version satisfies the mod's minimum required version.
+# Returns 1 if the game version is compatible with the mod, 0 if not
 check_game_version() {
-  local game_version="$1"
-  local mod_version="$2"
+  local mod_required_version="$1"  # The minimum Factorio version required by the mod
+  local current_game_version="$2"  # The current Factorio version
 
-  local game_major mod_major game_minor mod_minor
-  game_major=$(echo "$game_version" | cut -d '.' -f1)
-  game_minor=$(echo "$game_version" | cut -d '.' -f2)
-  mod_major=$(echo "$mod_version" | cut -d '.' -f1)
-  mod_minor=$(echo "$mod_version" | cut -d '.' -f2)
+  local mod_major mod_minor game_major game_minor
+  mod_major=$(echo "$mod_required_version" | cut -d '.' -f1)
+  mod_minor=$(echo "$mod_required_version" | cut -d '.' -f2)
+  game_major=$(echo "$current_game_version" | cut -d '.' -f1)
+  game_minor=$(echo "$current_game_version" | cut -d '.' -f2)
 
-  if [[ "$game_major" -ne "$mod_major" ]]; then
+  # If game major version is greater than mod's required major version, it's compatible
+  if [[ "$game_major" -gt "$mod_major" ]]; then
+    echo 1
+    return
+  fi
+
+  # If game major version is less than mod's required major version, it's not compatible
+  if [[ "$game_major" -lt "$mod_major" ]]; then
     echo 0
     return
   fi
 
-  if [[ "$mod_minor" -ge "$game_minor" ]]; then
+  # Major versions are equal, check minor versions
+  # Game minor version must be >= mod's required minor version
+  if [[ "$game_minor" -ge "$mod_minor" ]]; then
     echo 1
   else
     echo 0
@@ -79,7 +88,7 @@ check_dependency_version()
       fi
       ;;
     ">")
-      if [[ "$(printf '%s\n%s\n' "$required_version" "$mod_version" | sort -V | head -n1)" == "$required_version" && "$required_version" != "$FACTORIO_VERSION" ]]; then
+      if [[ "$(printf '%s\n%s\n' "$required_version" "$mod_version" | sort -V | head -n1)" == "$required_version" && "$required_version" != "$mod_version" ]]; then
         echo 1
       else
         echo 0
@@ -93,7 +102,7 @@ check_dependency_version()
       fi
       ;;
     "<")
-      if [[ "$(printf '%s\n%s\n' "$required_version" "$mod_version" | sort -V | tail -n1)" == "$required_version" && "$required_version" != "$FACTORIO_VERSION" ]]; then
+      if [[ "$(printf '%s\n%s\n' "$required_version" "$mod_version" | sort -V | tail -n1)" == "$required_version" && "$required_version" != "$mod_version" ]]; then
         echo 1
       else
         echo 0
@@ -116,11 +125,15 @@ get_mod_info()
 {
   local mod_info_json="$1"
 
+  # Process mod releases from newest to oldest, looking for a compatible version
   while IFS= read -r mod_release_info; do
     local mod_version mod_factorio_version
     mod_version=$(echo "$mod_release_info" | jq -r ".version")
     mod_factorio_version=$(echo "$mod_release_info" | jq -r ".info_json.factorio_version")
 
+    # Check if this mod version is compatible with our Factorio version
+    # This prevents downloading mods that require a newer Factorio version (fixes #468)
+    # and ensures backward compatibility (e.g., Factorio 2.0 can use 1.x mods) (fixes #517)
     if [[ $(check_game_version "$mod_factorio_version" "$FACTORIO_VERSION") == 0 ]]; then
       echo "  Skipping mod version $mod_version because of factorio version mismatch"  >&2
       continue
@@ -214,9 +227,12 @@ update_mod()
   return 0
 }
 
+# Process all enabled mods from mod-list.json, but skip built-in mods
+# The Space Age DLC includes built-in mods (elevated-rails, quality, space-age) that should not be downloaded
 if [[ -f $MOD_DIR/mod-list.json ]]; then
   jq -r ".mods|map(select(.enabled))|.[].name" "$MOD_DIR/mod-list.json" | while read -r mod; do
-    if [[ $mod != base ]]; then
+    # Skip base mod and DLC built-in mods
+    if [[ $mod != base ]] && [[ $mod != elevated-rails ]] && [[ $mod != quality ]] && [[ $mod != space-age ]]; then
       update_mod "$mod" || true
     fi
   done