services: linux: Minor improvements for thinkfan-service

modules/radix/services/linux.scm

@@ -1,57 +1,66 @@
 (define-module (radix services linux)
-  #:use-module (gnu)
   #:use-module (radix packages linux)
+  #:use-module (gnu)
   #:use-module (gnu services)
   #:use-module (gnu services shepherd)
+  #:use-module (gnu services configuration)
   #:use-module (guix gexp)
   #:use-module (guix records)
+  #:use-module (ice-9 curried-definitions)
   #:export (thinkfan-configuration
             make-thinkfan-configuration
             thinkfan-configuration?
 
-            thinkfan-configuration-requirement
             thinkfan-configuration-pid-file
             thinkfan-configuration-config-file
             thinkfan-configuration-log-file
-            thinkfan-configuration-respawn
             thinkfan-configuration-extra-options
 
             thinkfan-shepherd-service
             thinkfan-service-type))
 
-(define-record-type* <thinkfan-configuration>
-  thinkfan-configuration make-thinkfan-configuration
-  thinkfan-configuration?
-  (requirement   thinkfan-configuration-requirement   ; list of symbols
-                 (default '(user-processes)))
-  (pid-file      thinkfan-configuration-pid-file      ; string
-                 (default "/var/run/thinkfan.pid"))
-  (config-file   thinkfan-configuration-config-file   ; string
-                 (default "/etc/thinkfan.conf"))
-  (log-file      thinkfan-configuration-log-file      ; string
-                 (default "/var/log/thinkfan.log"))
-  (respawn?      thinkfan-configuration-respawn?      ; boolean
-                 (default #t))
-  (extra-options thinkfan-configuration-extra-options ; list of strings
-                 (default '())))
+(define ((list-of predicate) x)
+  (null? (filter (negate predicate) x)))
 
-(define (thinkfan-shepherd-service config)
-  (match-record config <thinkfan-configuration>
-    (requirement pid-file config-file log-file respawn? extra-options)
+(define list-of-symbols?
+  (list-of symbol?))
+
+(define list-of-strings?
+  (list-of string?))
+
+(define-configuration/no-serialization thinkfan-configuration
+  (pid-file
+   (string "/var/run/thinkfan.pid")
+   "Where to store the PID file.")
+  (config-file
+   (string "/etc/thinkfan.conf")
+   "Configuration file to use.")
+  (log-file
+   (string "/var/log/thinkfan.log")
+    "File where ‘thinkfan’ writes its log to.")
+  (extra-options
+   (list-of-strings '())
+   "This option provides an “escape hatch” for the user to provide
+arbitrary command-line arguments to ‘thinkfan’ as a list of strings."))
+
+(define thinkfan-shepherd-service
+  (match-record-lambda <thinkfan-configuration>
+    (pid-file config-file log-file extra-options)
     (list (shepherd-service
            (provision '(thinkfan))
            (documentation
             "Adjust fan level according to configured temperature limits.")
-           (requirement requirement)
+           (requirement '(user-processes kernel-module-loader))
            (start #~(make-forkexec-constructor
-                      (list (string-append #$thinkfan-next "/sbin/thinkfan")
-                            (string-append "-c" #$config-file)
-                            #$@extra-options)
-                     #:pid-file #$pid-file
-                     #:log-file #$log-file))
+                      (list (string-append #$thinkfan-next
+                                           "/sbin/thinkfan")
+                             "-n" #$@extra-options
+                             "-c" #$config-file)
+                     #:log-file #$log-file
+                     #:pid-file #$pid-file))
            (stop #~(make-kill-destructor))
            (one-shot? #t)
-           (respawn? respawn?)))))
+           (respawn? #t)))))
 
 (define thinkfan-modprobe-config
   (plain-file "thinkfan.conf"