gnu: services: Add readymedia service.

* gnu/services/upnp.scm, gnu/tests/upnp.scm: New files.
* gnu/local.mk (GNU_SYSTEM_MODULES): Add them.
* doc/guix.texi (Miscellaneous Services): Document the service.

Change-Id: I6a3c9db9e7504df308038343ed48e4409a323581
Signed-off-by: Arun Isaac <arunisaac@systemreboot.net>

4 files changed, 465 insertions, 0 deletions

diff --git a/doc/guix.texi b/doc/guix.texi
index b91d229d7c..b9f71527a3 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -41774,6 +41774,107 @@ invokation.
 
 @end deftp
 
+@c %end of fragment
+
+@cindex DLNA/UPnP
+@subsubheading DLNA/UPnP Services
+
+The @code{(gnu services upnp)} module offers services related to
+@acronym{UPnP, Universal Plug and Play} and @acronym{DLNA, Digital
+Living Network Alliance}, networking protocols that can be used for
+media streaming and device interoperability within a local network.  For
+now, this module provides the @code{readymedia-service-type}.
+
+@uref{https://sourceforge.net/projects/minidlna/, ReadyMedia} (formerly
+known as MiniDLNA) is a DLNA/UPnP-AV media server.  The project's
+daemon, @code{minidlnad}, can serve media files (audio, pictures, and
+video) to DLNA/UPnP-AV clients available on the network.
+@code{readymedia-service-type} is a Guix service that wraps around
+ReadyMedia's @code{minidlnad}.
+
+Consider the following configuration:
+@lisp
+(use-service-modules upnp @dots{})
+
+(operating-system
+  @dots{}
+  (services
+   (list (service readymedia-service-type
+                  (readymedia-configuration
+                   (media-directoriess
+                    (list (readymedia-media-directory
+                           (path "/media/audio")
+                           (types '(A)))
+                          (readymedia-media-directory
+                           (path "/media/video")
+                           (types '(V)))
+                          (readymedia-media-directory
+                           (path "/media/misc"))))
+                   (extra-config '(("notify_interval" . 60)))))
+         @dots{})))
+@end lisp
+
+This sets up the ReadyMedia daemon to serve files from the media folders
+specified in @code{media-directories}.  The @code{media-directories}
+field is mandatory.  All other fields (such as network ports and the
+server name) come with a predefined default and can be omitted.
+
+@c %start of fragment
+
+@deftp {Data Type} readymedia-configuration
+Available @code{readymedia-configuration} fields are:
+
+@table @asis
+@item @code{readymedia} (default: @code{readymedia}) (type: package)
+The ReadyMedia package to be used for the service.
+
+@item @code{friendly-name} (default: @code{#f}) (type: maybe-string)
+A custom name that will be displayed on connected clients.
+
+@item @code{media-directories} (type: list)
+The list of media folders to serve content from.  Each item is a
+@code{readymedia-media-directory}.
+
+@item @code{cache-directory} (default: @code{"/var/cache/readymedia"}) (type: string)
+A folder for ReadyMedia's cache files.  If not existing already, the
+folder will be created as part of the service activation and the
+ReadyMedia user will be assigned ownership.
+
+@item @code{log-directory} (default: @code{"/var/log/readymedia"}) (type: string)
+A folder for ReadyMedia's log files.  If not existing already, the
+folder will be created as part of the service activation and the
+ReadyMedia user will be assigned ownership.
+
+@item @code{port} (default: @code{#f}) (type: maybe-integer)
+A custom port that the service will be listening on.
+
+@item @code{extra-config} (default: @code{'()}) (type: alist)
+An association list of further options, as accepted by ReadyMedia.
+@end table
+
+@end deftp
+
+@c %end of fragment
+
+@c %start of fragment
+
+@deftp {Data Type} readymedia-media-directory
+A @code{media-directories} entry includes a folder @code{path} and,
+optionally, the @code{types} of media files included within the
+folder.
+
+@table @asis
+@item @code{path} (type: string)
+The media folder location.
+
+@item @code{types} (default: @code{'()}) (type: list)
+A list indicating the types of file included in the media folder.
+Valid values are combinations of individual media types, i.e. symbol
+@code{A} for audio, @code{P} for pictures, @code{V} for video.  An
+empty list means that no type is specified.
+@end table
+
+@end deftp
 
 @c %end of fragment
 
diff --git a/gnu/local.mk b/gnu/local.mk
index 29d76e7bce..81031c9bdd 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -756,6 +756,7 @@ GNU_SYSTEM_MODULES =				\
   %D%/services/syncthing.scm			\
   %D%/services/sysctl.scm			\
   %D%/services/telephony.scm			\
+  %D%/services/upnp.scm				\
   %D%/services/version-control.scm              \
   %D%/services/vnc.scm				\
   %D%/services/vpn.scm				\
@@ -846,6 +847,7 @@ GNU_SYSTEM_MODULES =				\
   %D%/tests/singularity.scm			\
   %D%/tests/ssh.scm				\
   %D%/tests/telephony.scm		        \
+  %D%/tests/upnp.scm				\
   %D%/tests/version-control.scm			\
   %D%/tests/virtualization.scm			\
   %D%/tests/vnc.scm				\
diff --git a/gnu/services/upnp.scm b/gnu/services/upnp.scm
new file mode 100644
index 0000000000..09121326fe
--- /dev/null
+++ b/gnu/services/upnp.scm
@@ -0,0 +1,207 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2024 Fabio Natali <me@fabionatali.com>
+;;;
+;;; 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 services upnp)
+  #:use-module (gnu build linux-container)
+  #:use-module (gnu packages admin)
+  #:use-module (gnu packages upnp)
+  #:use-module (gnu services admin)
+  #:use-module (gnu services base)
+  #:use-module (gnu services shepherd)
+  #:use-module (gnu services)
+  #:use-module (gnu system file-systems)
+  #:use-module (gnu system shadow)
+  #:use-module (guix gexp)
+  #:use-module (guix least-authority)
+  #:use-module (guix modules)
+  #:use-module (guix records)
+  #:use-module (ice-9 match)
+  #:export (%readymedia-default-cache-directory
+            %readymedia-default-log-directory
+            %readymedia-default-port
+            %readymedia-log-file
+            %readymedia-user-account
+            %readymedia-user-group
+            readymedia-configuration
+            readymedia-configuration?
+            readymedia-configuration-readymedia
+            readymedia-configuration-port
+            readymedia-configuration-cache-directory
+            readymedia-configuration-extra-config
+            readymedia-configuration-friendly-name
+            readymedia-configuration-log-directory
+            readymedia-configuration-media-directories
+            readymedia-media-directory
+            readymedia-media-directory-path
+            readymedia-media-directory-types
+            readymedia-media-directory?
+            readymedia-service-type))
+
+;;; Commentary:
+;;;
+;;; UPnP services.
+;;;
+;;; Code:
+
+(define %readymedia-default-cache-directory "/var/cache/readymedia")
+(define %readymedia-default-log-directory "/var/log/readymedia")
+(define %readymedia-log-file "minidlna.log")
+(define %readymedia-user-group "readymedia")
+(define %readymedia-user-account "readymedia")
+
+(define-record-type* <readymedia-configuration>
+  readymedia-configuration make-readymedia-configuration
+  readymedia-configuration?
+  (readymedia readymedia-configuration-readymedia
+              (default readymedia))
+  (port readymedia-configuration-port
+        (default #f))
+  (cache-directory readymedia-configuration-cache-directory
+                   (default %readymedia-default-cache-directory))
+  (log-directory readymedia-configuration-log-directory
+                 (default %readymedia-default-log-directory))
+  (friendly-name readymedia-configuration-friendly-name
+                 (default #f))
+  (media-directories readymedia-configuration-media-directories)
+  (extra-config readymedia-configuration-extra-config
+                (default '())))
+
+;; READYMEDIA-MEDIA-DIR is a record that indicates the path of a media folder
+;; and the types of media included within it. Allowed individual types are the
+;; symbols 'A' for audio, 'V' for video, and 'P' for pictures. The types field
+;; can contain any combination of individual types; an empty list means that
+;; no type is specified.
+(define-record-type* <readymedia-media-directory>
+  readymedia-media-directory make-readymedia-media-directory
+  readymedia-media-directory?
+  (path readymedia-media-directory-path)
+  (types readymedia-media-directory-types
+         (default '())))
+
+(define (readymedia-configuration->config-file config)
+  "Return the ReadyMedia/MiniDLNA configuration file corresponding to CONFIG."
+  (match-record config <readymedia-configuration>
+    (port friendly-name cache-directory log-directory media-directories extra-config)
+    (apply mixed-text-file
+           "minidlna.conf"
+           "db_dir=" cache-directory "\n"
+           "log_dir=" log-directory "\n"
+           (if friendly-name
+               (string-append "friendly_name=" friendly-name "\n")
+               "")
+           (if port
+               (string-append "port=" (number->string port) "\n")
+               "")
+           (append (map (match-record-lambda <readymedia-media-directory>
+                            (path types)
+                          (apply string-append
+                                 "media_dir="
+                                 (append (map symbol->string types)
+                                         (match types
+                                           (() (list))
+                                           (_ (list ",")))
+                                         (list path))))
+                        media-directories)
+                   (map (match-lambda
+                          ((key . value)
+                           (string-append key "=" value "\n")))
+                        extra-config)))))
+
+(define (readymedia-shepherd-service config)
+  "Return a least-authority ReadyMedia/MiniDLNA Shepherd service."
+  (match-record config <readymedia-configuration>
+    (cache-directory log-directory media-directories)
+    (let ((minidlna-conf (readymedia-configuration->config-file config)))
+      (shepherd-service
+       (documentation "Run the ReadyMedia/MiniDLNA daemon.")
+       (provision '(readymedia))
+       (requirement '(networking user-processes))
+       (start
+        #~(make-forkexec-constructor
+           (list #$(least-authority-wrapper
+                    (file-append (readymedia-configuration-readymedia config)
+                                 "/sbin/minidlnad")
+                    #:name "minidlna"
+                    #:mappings
+                    (cons* (file-system-mapping
+                            (source cache-directory)
+                            (target source)
+                            (writable? #t))
+                           (file-system-mapping
+                            (source log-directory)
+                            (target source)
+                            (writable? #t))
+                           (file-system-mapping
+                            (source minidlna-conf)
+                            (target source))
+                           (map (lambda (directory)
+                                  (file-system-mapping
+                                   (source (readymedia-media-directory-path directory))
+                                   (target source)))
+                                media-directories))
+                    #:namespaces (delq 'net %namespaces))
+                 "-f"
+                 #$minidlna-conf
+                 "-S")
+           #:log-file #$(string-append log-directory "/" %readymedia-log-file)
+           #:user #$%readymedia-user-account
+           #:group #$%readymedia-user-group))
+       (stop #~(make-kill-destructor))))))
+
+(define readymedia-accounts
+  (list (user-account
+         (name "readymedia")
+         (group "readymedia")
+         (system? #t)
+         (comment "ReadyMedia/MiniDLNA daemon user")
+         (home-directory "/var/empty")
+         (shell (file-append shadow "/sbin/nologin")))
+        (user-group
+         (name "readymedia")
+         (system? #t))))
+
+(define (readymedia-activation config)
+  "Set up directories for ReadyMedia/MiniDLNA."
+  (match-record config <readymedia-configuration>
+    (cache-directory log-directory media-directories)
+    (with-imported-modules (source-module-closure '((gnu build activation)))
+      #~(begin
+          (use-modules (gnu build activation))
+
+          (for-each (lambda (directory)
+                      (unless (file-exists? directory)
+                        (mkdir-p/perms directory
+                                       (getpw #$%readymedia-user-account)
+                                       #o755)))
+                    (list #$cache-directory
+                          #$log-directory
+                          #$@(map readymedia-media-directory-path
+                                  media-directories)))))))
+
+(define readymedia-service-type
+  (service-type
+   (name 'readymedia)
+   (extensions
+    (list (service-extension shepherd-root-service-type
+                             (compose list readymedia-shepherd-service))
+          (service-extension account-service-type
+                             (const readymedia-accounts))
+          (service-extension activation-service-type
+                             readymedia-activation)))
+   (description
+    "Run @command{minidlnad}, the ReadyMedia/MiniDLNA media server.")))
diff --git a/gnu/tests/upnp.scm b/gnu/tests/upnp.scm
new file mode 100644
index 0000000000..e4bce30d89
--- /dev/null
+++ b/gnu/tests/upnp.scm
@@ -0,0 +1,155 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2024 Fabio Natali <me@fabionatali.com>
+;;;
+;;; 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 tests upnp)
+  #:use-module (gnu services)
+  #:use-module (gnu services networking)
+  #:use-module (gnu services upnp)
+  #:use-module (gnu system vm)
+  #:use-module (gnu tests)
+  #:use-module (guix gexp)
+  #:export (%test-readymedia))
+
+(define %readymedia-cache-file "files.db")
+(define %readymedia-cache-path
+  (string-append %readymedia-default-cache-directory
+                 "/"
+                 %readymedia-cache-file))
+(define %readymedia-log-path
+  (string-append %readymedia-default-log-directory
+                 "/"
+                 %readymedia-log-file))
+(define %readymedia-default-port 8200)
+(define %readymedia-media-directory "/media")
+(define %readymedia-configuration-test
+  (readymedia-configuration
+   (media-directories
+    (list (readymedia-media-directory (path %readymedia-media-directory)
+                                      (types '(A V)))))))
+
+(define (run-readymedia-test)
+  (define os
+    (marionette-operating-system
+     (simple-operating-system
+      (service dhcp-client-service-type)
+      (service readymedia-service-type
+               %readymedia-configuration-test))
+     #:imported-modules '((gnu services herd)
+                          (json parser))
+     #:requirements '(readymedia)))
+
+  (define test
+    (with-imported-modules '((gnu build marionette))
+      #~(begin
+          (use-modules (gnu build marionette)
+                       (srfi srfi-64))
+
+          (define marionette
+            (make-marionette
+             (list #$(virtual-machine
+                      (operating-system os)
+                      (port-forwardings '())))))
+
+          (test-runner-current (system-test-runner #$output))
+          (test-begin "readymedia")
+
+          ;; ReadyMedia user
+          (test-assert "ReadyMedia user exists"
+            (marionette-eval
+             '(begin
+                (getpwnam #$%readymedia-user-account)
+                #t)
+             marionette))
+          (test-assert "ReadyMedia group exists"
+            (marionette-eval
+             '(begin
+                (getgrnam #$%readymedia-user-group)
+                #t)
+             marionette))
+
+          ;; Cache directory and file
+          (test-assert "cache directory exists"
+            (marionette-eval
+             '(eq? (stat:type (stat #$%readymedia-default-cache-directory))
+                   'directory)
+             marionette))
+          (test-assert "cache directory has correct ownership"
+            (marionette-eval
+             '(let ((cache-dir (stat #$%readymedia-default-cache-directory))
+                    (user (getpwnam #$%readymedia-user-account)))
+                (and (eqv? (stat:uid cache-dir) (passwd:uid user))
+                     (eqv? (stat:gid cache-dir) (passwd:gid user))))
+             marionette))
+          (test-assert "cache directory has expected permissions"
+            (marionette-eval
+             '(eqv? (stat:perms (stat #$%readymedia-default-cache-directory))
+                    #o755)
+             marionette))
+
+          ;; Log directory and file
+          (test-assert "log directory exists"
+            (marionette-eval
+             '(eq? (stat:type (stat #$%readymedia-default-log-directory))
+                   'directory)
+             marionette))
+          (test-assert "log directory has correct ownership"
+            (marionette-eval
+             '(let ((log-dir (stat #$%readymedia-default-log-directory))
+                    (user (getpwnam #$%readymedia-user-account)))
+                (and (eqv? (stat:uid log-dir) (passwd:uid user))
+                     (eqv? (stat:gid log-dir) (passwd:gid user))))
+             marionette))
+          (test-assert "log directory has expected permissions"
+            (marionette-eval
+             '(eqv? (stat:perms (stat #$%readymedia-default-log-directory))
+                    #o755)
+             marionette))
+          (test-assert "log file exists"
+            (marionette-eval
+             '(file-exists? #$%readymedia-log-path)
+             marionette))
+          (test-assert "log file has expected permissions"
+            (marionette-eval
+             '(eqv? (stat:perms (stat #$%readymedia-log-path))
+                    #o640)
+             marionette))
+
+          ;; Service
+          (test-assert "ReadyMedia service is running"
+            (marionette-eval
+             '(begin
+                (use-modules (gnu services herd)
+                             (srfi srfi-1))
+                (live-service-running
+                 (find (lambda (live-service)
+                         (memq 'readymedia
+                               (live-service-provision live-service)))
+                       (current-services))))
+             marionette))
+          (test-assert "ReadyMedia service is listening for connections"
+            (wait-for-tcp-port #$%readymedia-default-port marionette))
+
+          (test-end))))
+
+  (gexp->derivation "readymedia-test" test))
+
+(define %test-readymedia
+  (system-test
+   (name "readymedia")
+   (description "Test the ReadyMedia service.")
+   (value (run-readymedia-test))))