Set up Minecraft server

4 files changed, 108 insertions, 1 deletions

diff --git a/tw/packages/games.scm b/tw/packages/games.scm
index 28ffbaa3..76520051 100644
--- a/tw/packages/games.scm
+++ b/tw/packages/games.scm
@@ -19,6 +19,7 @@
   #:use-module (gnu packages gtk)
   #:use-module (gnu packages guile)
   #:use-module (gnu packages image)
+  #:use-module (gnu packages java)
   #:use-module (gnu packages linux)
   #:use-module (gnu packages lua)
   #:use-module (gnu packages pkg-config)
@@ -606,3 +607,46 @@ Create the route of your dreams in a world where you set the pace, and embark
 on an ever-expanding railway extravaganza.")
     (license (nonguix-license:undistributable
               "file://data/noarch/docs/End User License Agreement.txt"))))
+
+
+;;; Minecraft server
+
+;; See versions in:
+;; https://piston-meta.mojang.com/mc/game/version_manifest.json
+;; ...which links to:
+;; https://piston-meta.mojang.com/v1/packages/111890b5a8c2fee9b77036f9f377b33df42c718a/1.20.6.json
+
+(define-public minecraft-server
+  (package
+    (name "minecraft-server")
+    (version "1.20.6")
+    (source
+     (origin
+       (method url-fetch)
+       (uri "https://piston-data.mojang.com/v1/objects/145ff0858209bcfc164859ba735d4199aafa1eea/server.jar")
+       (sha256 (base32 "1v6755nch6v8q4jvc8liprw50mpx8wnnaq7cy03fb0m7ih0ivl66"))))
+    (build-system trivial-build-system)
+    (arguments
+     `(#:builder
+       ,(with-imported-modules
+            (source-module-closure '((guix build utils)))
+          #~(begin
+              (use-modules (guix build utils))
+              (for-each (lambda (dir)
+                          (mkdir-p (string-append #$output "/" dir)))
+                        '("bin" "libexec"))
+              (copy-file #$source (string-append #$output "/libexec/server.jar"))
+              (call-with-output-file (string-append #$output "/bin/minecraft-server")
+                (lambda (port)
+                  (format port "#!~a/bin/guile --no-auto-compile~%!#~%" #$guile-3.0)
+                  (write `(apply execl #$(file-append openjdk21 "/bin/java")
+                                 "java" "-jar" ,(string-append #$output "/libexec/server.jar")
+                                 (cdr (command-line)))
+                         port)
+                  (chmod port #o555)))))))
+    (inputs (list openjdk21 guile-3.0))
+    (home-page "https://www.minecraft.net/")
+    (synopsis "Server for the well-known block building sandbox game")
+    (description "Server software for Minecraft.")
+    (license (nonguix-license:undistributable
+              "https://www.minecraft.net/en-us/eula"))))
diff --git a/tw/services/games.scm b/tw/services/games.scm
new file mode 100644
index 00000000..7b7d8a4b
--- /dev/null
+++ b/tw/services/games.scm
@@ -0,0 +1,60 @@
+(define-module (tw services games)
+  #:use-module ((gnu packages admin) #:select (shadow))
+  #:use-module (gnu services)
+  #:use-module (gnu services configuration)
+  #:use-module (gnu services shepherd)
+  #:use-module (gnu system shadow)
+  #:use-module (guix gexp)
+  #:use-module (guix records)
+  #:use-module (tw packages games)
+  #:export (minecraft-server-service-type
+            minecraft-server-configuration))
+
+;; TODO: backups of Minecraft data
+
+(define-configuration/no-serialization minecraft-server-configuration
+  (data-location (string "/var/lib/minecraft-server") "Path on disk where
+server data will be stored.")
+  (port (integer 25565) "The port to bind the main server to.")
+  (user-name (string "minecraft") "UNIX username to create for the server.")
+  (group-name (string "minecraft") "UNIX group to create for the server."))
+
+(define (minecraft-server-shepherd config)
+  (match-record config <minecraft-server-configuration> (data-location port user-name group-name)
+    (list (shepherd-service
+           (provision '(minecraft-server))
+           (requirement '(networking))
+           (documentation "Run a Minecraft server.")
+           (start #~(make-forkexec-constructor
+                     (list #$(file-append minecraft-server "/bin/minecraft-server")
+                           "--nogui" "--port" #$(number->string port))
+                     #:user #$user-name #:group #$group-name
+                     #:directory #$data-location))
+           (stop #~(make-kill-destructor))))))
+
+(define (minecraft-server-activation config)
+  (match-record config <minecraft-server-configuration> (data-location)
+    #~(with-output-to-file (string-append #$data-location "/eula.txt")
+        (lambda () (display "eula=true") (newline)))))
+
+(define (minecraft-server-accounts config)
+  (match-record config <minecraft-server-configuration> (data-location user-name group-name)
+    (list (user-account
+           (name user-name)
+           (group group-name)
+           (comment "Minecraft server user")
+           (system? #t)
+           (home-directory data-location)
+           (shell (file-append shadow "/sbin/nologin")))
+          (user-group
+           (name group-name)
+           (system? #t)))))
+
+(define minecraft-server-service-type
+  (service-type
+   (name 'minecraft-server)
+   (extensions (list (service-extension shepherd-root-service-type minecraft-server-shepherd)
+                     (service-extension activation-service-type minecraft-server-activation)
+                     (service-extension account-service-type minecraft-server-accounts)))
+   (default-value (minecraft-server-configuration))
+   (description "Run a Minecraft server.")))
diff --git a/tw/system.scm b/tw/system.scm
index e706d84c..eb5bc914 100644
--- a/tw/system.scm
+++ b/tw/system.scm
@@ -55,7 +55,7 @@
     ("btl.twilken.net" . 23022)
     ("twilkenlaptop.cern.ch" . 22022)))
 
-(define (tw-openssh-service host-name work-system?)
+(define* (tw-openssh-service host-name #:optional (work-system? #f))
   "Configure the SSH server for remote login."
   ;; SSH login, allowing access only for me.  To give more public keys
   ;; access, extend `openssh-service-type'.
diff --git a/tw/system/lud.scm b/tw/system/lud.scm
index d6d60be6..fc9e85c6 100644
--- a/tw/system/lud.scm
+++ b/tw/system/lud.scm
@@ -6,6 +6,7 @@
   #:use-module (guix gexp)
   #:use-module (tw packages php)
   #:use-module (tw services dns)
+  #:use-module (tw services games)
   #:use-module (tw services nextcloud)
   #:use-module (tw services matrix)
   #:use-module (tw services media)
@@ -94,6 +95,8 @@
                (data-path "/var/data/paperless")
                (secret-key-file "/etc/paperless/secret-key")))
 
+            (service minecraft-server-service-type)
+
             ;; Allow anonymous git access via Wireguard, e.g. to this channel's git repo.
             ;; Repos are only published if they contain a `git-daemon-export-ok' file.
             (service git-daemon-service-type