services: add cloud-init service

diff --git a/infiniteadaptability/services/cloud-init.scm b/infiniteadaptability/services/cloud-init.scm
new file mode 100644 (file)
index 0000000..39e4ccf
--- /dev/null
+++ b/infiniteadaptability/services/cloud-init.scm
@@ -0,0 +1,124 @@
+(define-module (infiniteadaptability services cloud-init)
+  #:use-module (gnu packages bash)
+  #:use-module (gnu packages python-web)
+  #:use-module (gnu services)
+  #:use-module (gnu services shepherd)
+  #:use-module (guix gexp)
+  #:use-module (guix records)
+  #:export (cloud-init-configuration cloud-init-service
+                                     cloud-init-service-type))
+
+(define-record-type* <cloud-init-configuration> cloud-init-configuration
+                     make-cloud-init-configuration
+  cloud-init-configuration?
+
+  (cloud-init cloud-init-configuration-cloud-init ;file-like
+              (default python-cloud-init))
+  (init-modules cloud-init-configuration-init-modules ;list of symbols
+                (default '(seed_random growpart
+                                       resizefs
+                                       disk_setup
+                                       mounts
+                                       set_hostname
+                                       update_hostname
+                                       users_groups
+                                       ssh
+                                       set_passwords)))
+  (config-modules cloud-init-configuration-config-modules ;list of symbols
+                  (default '()))
+  (final-modules cloud-init-configuration-final-modules ;list of symbols
+                 (default '(ssh_authkey_fingerprints)))
+  (extra-configuration-files
+   cloud-init-configuration-extra-configuration-files ;list of file-likes
+   (default '())))
+
+(define %cloud-dir
+  "/etc/cloud")
+
+(define %cloud-cfg
+  (string-append %cloud-dir "/cloud.cfg"))
+
+(define %cloud-cfg-d
+  (string-append %cloud-dir "/cloud.cfg.d"))
+
+(define (cloud-init-initialization init-modules config-modules final-modules
+                                   extra)
+  "Return the gexp to initialize the cloud-init configuration files"
+  #~(begin
+      (use-modules (srfi srfi-1)
+                   (srfi srfi-2)
+                   (guix build utils))
+
+      (define reduce-modules
+        (lambda (mods)
+          (string-join (map (lambda (mod)
+                              (string-append "\n  - "
+                                             (symbol->string mod))) mods))))
+
+      (mkdir-p #$%cloud-cfg-d)
+
+      (unless (null? '(#$@extra))
+        (for-each (lambda (file)
+                    (symlink (cadr file)
+                             (string-append #$%cloud-cfg-d "/"
+                                            (car file))))
+                  '(#$@extra)))
+
+      (call-with-output-file #$%cloud-cfg
+        (lambda (p)
+          (display "#cloud-config\n" p)
+
+          (unless (null? '(#$@init-modules))
+            (display (string-append "cloud_init_modules:"
+                                    (reduce-modules '(#$@init-modules)) "\n\n")
+                     p))
+          (unless (null? '(#$@config-modules))
+            (display (string-append "cloud_config_modules:"
+                                    (reduce-modules '(#$@config-modules))
+                                    "\n\n") p))
+          (unless (null? '(#$@final-modules))
+            (display (string-append "cloud_final_modules:"
+                                    (reduce-modules '(#$@final-modules))
+                                    "\n\n") p))))))
+
+(define (cloud-init-activation config)
+  "Return the activation gexp for CONFIG."
+  #~(begin
+      (use-modules (guix build utils))
+      #$(cloud-init-initialization (cloud-init-configuration-init-modules
+                                    config)
+                                   (cloud-init-configuration-config-modules
+                                    config)
+                                   (cloud-init-configuration-final-modules
+                                    config)
+                                   (cloud-init-configuration-extra-configuration-files
+                                    config))))
+
+(define (cloud-init-service config)
+  "Return a <cloud-init-service> for cloud-init with CONFIG."
+  (define cloud-init
+    (cloud-init-configuration-cloud-init config))
+
+  (define cloud-init-command
+    #~(list (string-append #$(cloud-init-configuration-cloud-init config)
+                           "/bin/cloud-init") "--all-stages"))
+
+  (list (shepherd-service (documentation "cloud-init service")
+                          (provision '(cloud-init))
+                          (requirement '(networking))
+                          (one-shot? #t)
+                          (start #~(fork+exec-command #$cloud-init-command
+                                                      #:log-file (string-append
+                                                                  "/var/log/cloud-init.log")
+                                                      #:environment-variables '
+                                                      ("PATH=/run/current-system/profile/bin:/run/current-system/profile/sbin:"))))))
+
+(define cloud-init-service-type
+  (service-type (name 'cloud-init)
+                (default-value (cloud-init-configuration))
+                (description "cloud init")
+                (extensions (list (service-extension
+                                   shepherd-root-service-type
+                                   cloud-init-service)
+                                  (service-extension activation-service-type
+                                                     cloud-init-activation)))))