services: Introduce extensible services.

This patch rewrites GuixSD services to make them extensible.

* gnu-system.am (GNU_SYSTEM_MODULES): Add gnu/services/dbus.scm.
* gnu/services.scm (<service>): Replace with new record type.
  (<service-extension>, <service-type>): New record types.
  (write-service-type, compute-boot-script, second-argument): New
  procedures.
  (%boot-service, boot-service-type): New variables.
  (file-union, directory-union, modprobe-wrapper,
  activation-service->script, activation-script,
  gexps->activation-gexp): New procedures.
  (activation-service-type, %activation-service): New variables.
  (etc-directory, files->etc-directory, etc-service): New procedures.
  (etc-service-type, setuid-program-service, firmware-service-type): New
  variables.
  (firmware->activation-gexp): New procedure.
  (&service-error, &missing-target-service-error,
  &ambiguous-target-service-error): New condition types.
  (service-back-edges, fold-services): New procedures.
* gnu/services/avahi.scm (<avahi-configuration>): New record type.
  (configuration-file): Replace keyword parameters with a single
  'config' parameter.
  (%avahi-accounts, %avahi-activation, avahi-service-type): New
  variables.
  (avahi-dmd-service): New procedure.
  (avahi-service): Rewrite using 'service' and 'avahi-configuration'.
* gnu/services/base.scm (%root-file-system-dmd-service,
  root-file-system-service-type): New variables.
  (root-file-system-service): Use them.
  (file-system->dmd-service-name): New procedure.
  (file-system-service-type): New variable.
  (file-system-service): Use it.  Replace keyword parameters with a
  single 'file-system' object.
  (user-unmount-service-type): New variable.
  (user-unmount-service): Use it.
  (user-processes-service-type): New variable.
  (user-processes-service): Use it.
  (host-name-service-type): New variable.
  (host-name-service): Use it.
  (console-keymap-service-type): New variable.
  (console-keymap-service): Use it.
  (console-font-service-type): New variable.
  (console-font-service): Use it.
  (mingetty-pam-service, mingetty-dmd-service): New procedures.
  (mingetty-service-type): New variable.
  (mingetty-service): Use it.
  (nscd-dmd-service): New procedure.
  (nscd-activation, nscd-service-type): New variables.
  (nscd-service): Use the latter.
  (syslog-service-type): New variable.
  (syslog-service): Use it.
  (<guix-configuration>): New record type.
  (%default-guix-configuration): New variable.
  (guix-dmd-service, guix-accounts, guix-activation): New procedures.
  (guix-service-type): New variable.
  (guix-service): Replace list of keyword parameters with a single
  'config' parameter.  Rewrite using 'service'.
  (<udev-configuration>): New record type.
  (udev-dmd-service): New procedure.
  (udev-service-type): New variable.
  (udev-service): Use it.
  (device-mapping-service-type): New variable.
  (device-mapping-service): Use it.
  (swap-service-type): New variable.
  (swap-service): Use it.
* gnu/services/databases.scm (<postgresql-configuration>): New record
  type.
  (%postgresql-accounts, postgresql-activation): New variables.
  (postgresql-dmd-service): New procedure.
  (postgresql-service): Rewrite using 'service' and
  'postgresql-configuration'.
* gnu/services/dbus.scm: New file.
* gnu/services/desktop.scm (dbus-configuration-directory, dbus-service):
  Remove.
  (wrapped-dbus-service): New procedure.
  (<upower-configuration>): New record type.
  (upower-configuration-file): Replace keyword parameters with single
  <upower-configuration> parameter.
  (%upower-accounts, %upower-activation): New variables.
  (upower-dbus-service, upower-dmd-service): New procedures.
  (upower-service-type): New variable.
  (upower-service): Rewrite using 'service' and 'upower-configuration'.
  (%colord-activation, %colord-accounts): New variables.
  (colord-dmd-service): New procedure.
  (colord-service-type): New variable.
  (colord-service): Rewrite using 'service'.
  (<geoclue-configuration>): New record type.
  (geoclue-configuration-file): Replace keyword parameters with a single
  'config' parameter.
  (geoclue-dbus-service, geoclue-dmd-service): New procedures.
  (%geoclue-accounts, geoclue-service-type): New variables.
  (geoclue-service): Rewrite using 'service' and
  'geoclue-configuration'.
  (%polkit-accounts, %polkit-pam-services, polkit-service-type): New
  variables.
  (polkit-dmd-service): New procedure.
  (polkit-service): Rewrite using 'service'.
  (<elogind-configuration>)[elogind]: New field.
  (elogind-dmd-service): New procedure.
  (elogind-service-type): New variable.
  (elogind-service): Rewrite using 'service'.
  (%desktop-services): Remove argument to 'dbus-service'.  Remove 'map'
  over %BASE-SERVICES.
* gnu/services/dmd.scm (dmd-boot-gexp): New procedure.
  (dmd-root-service-type, %dmd-root-service): New variables.
  (dmd-service-type): New macro.
  (<dmd-service>): New record type.
* gnu/services/lirc.scm (<lirc-configuration>): New record type.
  (%lirc-activation): New variable.
  (lirc-dmd-service): New procedure.
  (lirc-service-type): New variable.
  (lirc-service): Rewrite using 'service' and 'lirc-configuration'.
* gnu/services/networking.scm (<static-networking>): New record type.
  (static-networking-service-type): New variable.
  (static-networking-service): Rewrite using 'service' and
  'static-networking'.
  (dhcp-client-service-type): New variable.
  (dhcp-client-service): Rewrite using 'service'.
  (<ntp-configuration>): New record type.
  (ntp-dmd-service): New procedure.
  (ntp-service-type): New variable.
  (ntp-service): New procedure.
  (%tor-accounts, tor-service-type): New variable.
  (tor-dmd-service): New procedure.
  (tor-service): Rewrite using 'service'.
  (<bitlbee-configuration>): New record type.
  (bitlbee-dmd-service): New procedure.
  (%bitlbee-accounts, %bitlbee-activation, bitlbee-service-type): New
  variables.
  (bitlbee-service): Rewrite using 'service'.
  (%wicd-activation): New variable.
  (wicd-dmd-service): New procedure.
  (wicd-service-type): New variable.
  (wicd-service): Rewrite using 'service'.
* gnu/services/ssh.scm (<lsh-configuration>): New record type.
  (activation): Rename to...
  (lsh-initialization): ... this.
  (lsh-activation, lsh-dmd-service, lsh-pam-services): New procedures.
  (lsh-service-type): New variable.
  (lsh-service): Rewrite using 'service' and 'lsh-configuration'.
* gnu/services/web.scm (<nginx-configuration>): New record type.
  (%nginx-accounts): New variable.
  (nginx-activation, nginx-dmd-service): New procedures.
  (nginx-service-type): New variable.
  (nginx-service): Rewrite using 'service' and 'nginx-configuration'.
* gnu/services/xorg.scm (<slim-configuration>): New record type.
  (slim-pam-service, slim-dmd-service): New procedures.
  (slim-service-type): New variable.
  (slim-service): Rewrite using 'service' and 'slim-configuration'.
* gnu/system.scm (file-union): Remove.
  (other-file-system-services): Adjust to new 'file-system-service'
  signature.
  (essential-services): Add #:container? parameter.  Add
  %DMD-ROOT-SERVICE, %ACTIVATION-SERVICE, and calls to
  'pam-root-service', 'account-service', 'operating-system-etc-service',
  and a SETUID-PROGRAM-SERVICE instance.
  (operating-system-services): Pass #:container? to 'essential-services.
  (etc-directory): Remove.
  (operating-system-etc-service): New procedure.  Rewrite as a call to
  'etc-service'.
  (operating-system-accounts): Change to not return accounts required by
  services.
  (operating-system-etc-directory): Rewrite as a call to 'fold-services'
  and 'etc-directory'.
  (user-group->gexp, user-account->gexp, modprobe-wrapper): Remove.
  (operating-system-activation-script): Rewrite as a call to
  'fold-services' and 'activation-service->script'.
  (operating-system-boot-script): Likewise.
  (operating-system-derivation): Add call to 'lower-object'.
  (emacs-site-file, emacs-site-directory, shells-file): Change to use
  'computed-file' and 'scheme-file' instead of the monadic procedures.
* gnu/system/install.scm (cow-store-service-type): New variable.
  (cow-store-service): Rewrite using 'service'.
  (/etc/configuration-files): New procedure.
  (configuration-template-service-type,
  %configuration-template-service): New variables.
  (configuration-template-service): Remove.
  (installation-services): Adjust accordingly.  Adjust argument to
  'guix-service'.
* gnu/system/linux.scm (/etc-entry, pam-root-service): New procedures.
  (pam-root-service-type): New variable.
* gnu/system/shadow.scm (user-group->gexp, user-account->gexp,
  account-activation, etc-skel, account-service): New procedures.
  (account-service-type): New variable.
* tests/services.scm: New file.
* doc/guix.texi (Base Services, Desktop Services): Adjust accordingly.
  (Defining Services): Rewrite.
* doc/images/service-graph.dot: New file.
* doc.am (DOT_FILES): Add it.
* po/guix/POTFILES.in: Add gnu/services.scm.

1 files changed, 122 insertions, 56 deletions

diff --git a/gnu/services/ssh.scm b/gnu/services/ssh.scm
index 3fa0976054..d3a6cfb33a 100644
--- a/gnu/services/ssh.scm
+++ b/gnu/services/ssh.scm
@@ -18,8 +18,9 @@
 
 (define-module (gnu services ssh)
   #:use-module (guix gexp)
-  #:use-module (guix store)
+  #:use-module (guix records)
   #:use-module (gnu services)
+  #:use-module (gnu services dmd)
   #:use-module (gnu system linux)                 ; 'pam-service'
   #:use-module (gnu packages lsh)
   #:export (lsh-service))
@@ -30,11 +31,32 @@
 ;;;
 ;;; Code:
 
+;; TODO: Export.
+(define-record-type* <lsh-configuration>
+  lsh-configuration make-lsh-configuration
+  lsh-configuration?
+  (lsh lsh-configuration-lsh
+       (default lsh))
+  (daemonic? lsh-configuration-daemonic?)
+  (host-key lsh-configuration-host-key)
+  (interfaces lsh-configuration-interfaces)
+  (port-number lsh-configuration-port-number)
+  (allow-empty-passwords? lsh-configuration-allow-empty-passwords?)
+  (root-login? lsh-configuration-root-login?)
+  (syslog-output? lsh-configuration-syslog-output?)
+  (pid-file? lsh-configuration-pid-file?)
+  (pid-file lsh-configuration-pid-file)
+  (x11-forwarding? lsh-configuration-x11-forwarding?)
+  (tcp/ip-forwarding? lsh-configuration-tcp/ip-forwarding?)
+  (password-authentication? lsh-configuration-password-authentication?)
+  (public-key-authentication? lsh-configuration-public-key-authentication?)
+  (initialize? lsh-configuration-initialize?))
+
 (define %yarrow-seed
   "/var/spool/lsh/yarrow-seed-file")
 
-(define (activation lsh host-key)
-  "Return the gexp to activate the LSH service for HOST-KEY."
+(define (lsh-initialization lsh host-key)
+  "Return the gexp to initialize the LSH service for HOST-KEY."
   #~(begin
       (unless (file-exists? #$%yarrow-seed)
         (system* (string-append #$lsh "/bin/lsh-make-seed")
@@ -70,6 +92,88 @@
                   (waitpid keygen)
                   (waitpid write-key))))))))))
 
+(define (lsh-activation config)
+  "Return the activation gexp for CONFIG."
+  #~(begin
+      (use-modules (guix build utils))
+      (mkdir-p "/var/spool/lsh")
+      #$(if (lsh-configuration-initialize? config)
+            (lsh-initialization (lsh-configuration-lsh config)
+                                (lsh-configuration-host-key config))
+            #t)))
+
+(define (lsh-dmd-service config)
+  "Return a <dmd-service> for lsh with CONFIG."
+  (define lsh (lsh-configuration-lsh config))
+  (define pid-file (lsh-configuration-pid-file config))
+  (define pid-file? (lsh-configuration-pid-file? config))
+  (define daemonic? (lsh-configuration-daemonic? config))
+  (define interfaces (lsh-configuration-interfaces config))
+
+  (define lsh-command
+    (append
+     (cons #~(string-append #$lsh "/sbin/lshd")
+           (if daemonic?
+               (let ((syslog (if (lsh-configuration-syslog-output? config)
+                                 '()
+                                 (list "--no-syslog"))))
+                 (cons "--daemonic"
+                       (if pid-file?
+                           (cons #~(string-append "--pid-file=" #$pid-file)
+                                 syslog)
+                           (cons "--no-pid-file" syslog))))
+               (if pid-file?
+                   (list #~(string-append "--pid-file=" #$pid-file))
+                   '())))
+     (cons* #~(string-append "--host-key="
+                             #$(lsh-configuration-host-key config))
+            #~(string-append "--password-helper=" #$lsh "/sbin/lsh-pam-checkpw")
+            #~(string-append "--subsystems=sftp=" #$lsh "/sbin/sftp-server")
+            "-p" (number->string (lsh-configuration-port-number config))
+            (if (lsh-configuration-password-authentication? config)
+                "--password" "--no-password")
+            (if (lsh-configuration-public-key-authentication? config)
+                "--publickey" "--no-publickey")
+            (if (lsh-configuration-root-login? config)
+                "--root-login" "--no-root-login")
+            (if (lsh-configuration-x11-forwarding? config)
+                "--x11-forward" "--no-x11-forward")
+            (if (lsh-configuration-tcp/ip-forwarding? config)
+                "--tcpip-forward" "--no-tcpip-forward")
+            (if (null? interfaces)
+                '()
+                (list (string-append "--interfaces="
+                                     (string-join interfaces ",")))))))
+
+  (define requires
+    (if (and daemonic? (lsh-configuration-syslog-output? config))
+        '(networking syslogd)
+        '(networking)))
+
+  (list (dmd-service
+         (documentation "GNU lsh SSH server")
+         (provision '(ssh-daemon))
+         (requirement requires)
+         (start #~(make-forkexec-constructor (list #$@lsh-command)))
+         (stop  #~(make-kill-destructor)))))
+
+(define (lsh-pam-services config)
+  "Return a list of <pam-services> for lshd with CONFIG."
+  (list (unix-pam-service
+         "lshd"
+         #:allow-empty-passwords?
+         (lsh-configuration-allow-empty-passwords? config))))
+
+(define lsh-service-type
+  (service-type (name 'lsh)
+                (extensions
+                 (list (service-extension dmd-root-service-type
+                                          lsh-dmd-service)
+                       (service-extension pam-root-service-type
+                                          lsh-pam-services)
+                       (service-extension activation-service-type
+                                          lsh-activation)))))
+
 (define* (lsh-service #:key
                       (lsh lsh)
                       (daemonic? #t)
@@ -114,58 +218,20 @@ passwords, and @var{root-login?} specifies whether to accept log-ins as
 root.
 
 The other options should be self-descriptive."
-  (define lsh-command
-    (append
-     (cons #~(string-append #$lsh "/sbin/lshd")
-           (if daemonic?
-               (let ((syslog (if syslog-output? '()
-                                 (list "--no-syslog"))))
-                 (cons "--daemonic"
-                       (if pid-file?
-                           (cons #~(string-append "--pid-file=" #$pid-file)
-                                 syslog)
-                           (cons "--no-pid-file" syslog))))
-               (if pid-file?
-                   (list #~(string-append "--pid-file=" #$pid-file))
-                   '())))
-     (cons* #~(string-append "--host-key=" #$host-key)
-            #~(string-append "--password-helper=" #$lsh "/sbin/lsh-pam-checkpw")
-            #~(string-append "--subsystems=sftp=" #$lsh "/sbin/sftp-server")
-            "-p" (number->string port-number)
-            (if password-authentication? "--password" "--no-password")
-            (if public-key-authentication?
-                "--publickey" "--no-publickey")
-            (if root-login?
-                "--root-login" "--no-root-login")
-            (if x11-forwarding?
-                "--x11-forward" "--no-x11-forward")
-            (if tcp/ip-forwarding?
-                "--tcpip-forward" "--no-tcpip-forward")
-            (if (null? interfaces)
-                '()
-                (list (string-append "--interfaces="
-                                     (string-join interfaces ",")))))))
-
-  (define requires
-    (if (and daemonic? syslog-output?)
-        '(networking syslogd)
-        '(networking)))
-
-  (service
-   (documentation "GNU lsh SSH server")
-   (provision '(ssh-daemon))
-   (requirement requires)
-   (start #~(make-forkexec-constructor (list #$@lsh-command)))
-   (stop  #~(make-kill-destructor))
-   (pam-services
-    (list (unix-pam-service
-           "lshd"
-           #:allow-empty-passwords? allow-empty-passwords?)))
-   (activate #~(begin
-                 (use-modules (guix build utils))
-                 (mkdir-p "/var/spool/lsh")
-                 #$(if initialize?
-                       (activation lsh host-key)
-                       #t)))))
+  (service lsh-service-type
+           (lsh-configuration (lsh lsh) (daemonic? daemonic?)
+                              (host-key host-key) (interfaces interfaces)
+                              (port-number port-number)
+                              (allow-empty-passwords? allow-empty-passwords?)
+                              (root-login? root-login?)
+                              (syslog-output? syslog-output?)
+                              (pid-file? pid-file?) (pid-file pid-file)
+                              (x11-forwarding? x11-forwarding?)
+                              (tcp/ip-forwarding? tcp/ip-forwarding?)
+                              (password-authentication?
+                               password-authentication?)
+                              (public-key-authentication?
+                               public-key-authentication?)
+                              (initialize? initialize?))))
 
 ;;; ssh.scm ends here