gnu: Add home-docker-cli-service-type.issue-70265

* gnu/home/services/containers.scm (home-docker-cli-service-type): New
variable;
* doc/guix.texi: document it;
* gnu/local.mk: add it.

Change-Id: I71e7a2805fe8754511c8e02ee4ae667e34e4aaf6

3 files changed, 202 insertions, 0 deletions

diff --git a/doc/guix.texi b/doc/guix.texi
index fc28a15980..c06d9e1ddb 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -46295,6 +46295,59 @@ You may specify a custom configuration by providing a
           (dicod-configuration @dots{})))
 @end lisp
 
+@subsubheading Container Services
+
+@cindex docker cli service, for Home
+The @code{(gnu home services containers)} module provides the following service:
+
+@defvar home-docker-cli-service-type
+This service allows for configuring the Docker command line interface, for
+example to make it aware of Guix provided plugins.
+@end defvar
+
+For example, you can use it like this to make Docker safely store your registry
+credentials with the system
+@uref{https://wiki.gnome.org/Projects/Libsecret, libsecret} compatible Secret service:
+
+@lisp
+(use-modules (gnu packages docker))
+
+(service home-docker-cli-service-type
+         (docker-cli-configuration
+           (creds-store "secretservice")
+           (cli-plugins
+             (list docker-credential-secretservice))
+           (extra-content ", \"auths\": @{\"https://index.docker.io/v1/\": @{@}@}")))
+@end lisp
+
+
+@c %start of fragment
+
+@deftp {Data Type} docker-cli-configuration
+Available @code{docker-cli-configuration} fields are:
+
+@table @asis
+@item @code{docker-cli} (default: @code{docker-cli}) (type: package)
+The Docker cli package installed to the Home profile.
+
+@item @code{creds-store} (type: maybe-string)
+A native secrets store used to store Docker credentials.
+
+@item @code{cli-plugins} (default: @code{()}) (type: list-of-docker-cli-plugins)
+A list of Docker cli plugin package records that will be configured to
+work with Docker's cli.
+
+@item @code{extra-content} (default: @code{""}) (type: string)
+Additional literal content that will be appended to Docker cli
+config.json.
+
+@end table
+
+@end deftp
+
+
+@c %end of fragment
+
 @node Invoking guix home
 @section Invoking @command{guix home}
 
diff --git a/gnu/home/services/containers.scm b/gnu/home/services/containers.scm
new file mode 100644
index 0000000000..89d6ad5f39
--- /dev/null
+++ b/gnu/home/services/containers.scm
@@ -0,0 +1,148 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2024 Giacomo Leidi <goodoldpaul@autistici.org>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify
+;;; it under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation, either version 3 of the License, or
+;;; (at your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful,
+;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu home services containers)
+  #:use-module (guix gexp)
+  #:use-module (guix packages)
+  #:use-module (gnu packages docker)
+  #:use-module (gnu services configuration)
+  #:use-module (gnu home services)
+  #:use-module (ice-9 match)
+  #:use-module (ice-9 string-fun)
+  #:export (docker-cli-configuration
+            docker-cli-configuration?
+            docker-cli-configuration-fields
+            docker-cli-configuration-docker-cli
+            docker-cli-configuration-creds-store
+            docker-cli-configuration-cli-plugins
+
+            home-docker-cli-service-type
+            home-docker-cli-configuration-file
+            docker-cli-configuration->json-fields))
+
+;; Turn field names, which are Scheme symbols into strings
+;; cli-plugins-extra-dirs -> cliPluginsExtraDirs
+(define (format-name name)
+  (define without-dashes (string-replace-substring (symbol->string name) "-" " "))
+  (define splitted (string-split without-dashes #\space))
+  (string-replace-substring
+   (apply string-append
+          `(,(car splitted)
+            ,@(map string-capitalize (cdr splitted))))
+   " " ""))
+
+(define (serialize-json-value name value)
+  #~(begin
+      (use-modules (ice-9 format))
+      (format #f "\"~a\": ~a" #$(format-name name) #$value)))
+
+(define (serialize-json-list values)
+  #~(string-append "["
+               (string-join
+                (map (lambda (s) (string-append "\"" s "\""))
+                     (list #$@values))
+                ", ")
+               "]"))
+
+(define (serialize-string field-name value)
+  (serialize-json-value field-name (string-append "\"" value "\"")))
+
+(define (serialize-maybe-string field-name value)
+  (if (maybe-value-set? value)
+      (serialize-string field-name value)
+      '()))
+
+(define (serialize-list-of-strings field-name value)
+  (serialize-json-value field-name (serialize-json-list value)))
+
+(define (serialize-list-of-docker-cli-plugins value)
+  (serialize-json-value 'cli-plugins-extra-dirs
+                        (serialize-json-list
+                         (map (lambda (p)
+                                (file-append p "/libexec/docker/cli-plugins"))
+                              value))))
+
+(define list-of-strings?
+  (list-of string?))
+
+(define list-of-docker-cli-plugins?
+  (list-of package?))
+
+(define-maybe string)
+
+(define-configuration/no-serialization docker-cli-configuration
+  (docker-cli
+   (package docker-cli)
+   "The Docker cli package installed to the Home profile.")
+  (creds-store
+   (maybe-string)
+   "A native secrets store used to store Docker credentials.")
+  (cli-plugins
+   (list-of-docker-cli-plugins '())
+   "A list of Docker cli plugin package records that will be configured to work with Docker's cli.")
+  (extra-content
+   (string "")
+   "Additional literal content that will be appended to Docker cli config.json."))
+
+(define docker-cli-configuration->json-fields
+  (lambda (config)
+    (filter (compose not (lambda (f) (or (null? f) (and (string? f) (string-null? f)))))
+            (map (lambda (f)
+                   (let ((field-name (configuration-field-name f))
+                         (type (configuration-field-type f))
+                         (value ((configuration-field-getter f) config)))
+                     (if (not (member field-name '(docker-cli extra-content)))
+                         (match type
+                           ('string
+                            (serialize-string field-name value))
+                           ('maybe-string
+                            (serialize-maybe-string field-name value))
+                           ('list-of-strings
+                            (serialize-list-of-strings field-name value))
+                           ('list-of-docker-cli-plugins
+                            (serialize-list-of-docker-cli-plugins value))
+                           (_
+                            (raise
+                             (formatted-message
+                              (G_ "Unknown docker-cli-configuration field type: ~a")
+                              type))))
+                         '())))
+                 docker-cli-configuration-fields))))
+
+(define (home-docker-cli-configuration-file config)
+  `((".docker/config.json"
+     ,(computed-file "docker-cli-config.json"
+       #~(with-output-to-file #$output
+           (lambda _
+             (display
+              (string-append "{"
+                             (string-join (list #$@(docker-cli-configuration->json-fields config)) ",")
+                             #$(docker-cli-configuration-extra-content config)
+                             "}\n"))))))))
+
+(define home-docker-cli-service-type
+  (service-type (name 'docker-cli)
+                (extensions (list (service-extension home-profile-service-type
+                                                     (lambda (config)
+                                                       `(,(docker-cli-configuration-docker-cli config)
+                                                         ,@(docker-cli-configuration-cli-plugins config))))
+                                  (service-extension home-files-service-type
+                                                     home-docker-cli-configuration-file)))
+                (default-value (docker-cli-configuration))
+                (description
+                 "This service install and configures Docker's command line interface.")))
diff --git a/gnu/local.mk b/gnu/local.mk
index ccff8648be..98f6c412d1 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -96,6 +96,7 @@ GNU_SYSTEM_MODULES =				\
   %D%/compression.scm				\
   %D%/home.scm					\
   %D%/home/services.scm			\
+  %D%/home/services/containers.scm		\
   %D%/home/services/desktop.scm			\
   %D%/home/services/dict.scm			\
   %D%/home/services/dotfiles.scm		\