Setup initial CLI configurations.

We want to move away from using global values for our
configuration. In this respect, we provide a way to provide
configurations at application startup via CLI arguments.

2 files changed, 92 insertions, 1 deletions

diff --git a/web/config.scm b/web/config.scm
new file mode 100644
index 0000000..9b3b9c2
--- /dev/null
+++ b/web/config.scm
@@ -0,0 +1,86 @@
+;;; Copyright © 2026  Frederick M Muriithi <fredmanglis@gmail.com>
+
+(define-module (web config)
+  #:use-module (srfi srfi-9 gnu)
+
+  #:use-module (config)
+  #:use-module (config api)
+  #:use-module (config parser sexp)
+
+  #:export (<gn-guile-config>
+            gn-guile-config-port
+            gn-guile-config-gn-docs-remote-url
+            gn-guile-config-gn-docs-local-checkout
+            gn-guile-config-gn-docs-working-branch
+
+            parse-cli-options
+            cli-options->gn-guile-config))
+
+(define-immutable-record-type <gn-guile-config>
+  (gn-guile-config port gn-docs-remote-url gn-docs-local-checkout
+                   gn-docs-working-branch)
+  gn-guile-config?
+  (port gn-guile-config-port)
+  (gn-docs-remote-url gn-guile-config-gn-docs-remote-url)
+  (gn-docs-local-checkout gn-guile-config-gn-docs-local-checkout)
+  (gn-docs-working-branch gn-guile-config-gn-docs-working-branch))
+
+
+(define string->exact (compose inexact->exact string->number))
+
+
+(define (user-port? parsed)
+  (and (positive? parsed) (>= parsed 1024) (<= parsed 49151)))
+
+
+(define (parse-cli-options cmd-line)
+  "Read configuration values from files and command-line options and convert them to appropriate data types."
+  (let ((config
+         (configuration (name 'gn-guile)
+                        (synopsis "gn-guile web service: provide services
+ to main Genenetwork service.")
+                        (description "gn-guile web service is a small
+service, written in GNU Guile, that provides some functionality to the main
+Genenetwork service in the background. This is not meant for direct user
+interaction.")
+                        (keywords
+                         (list (switch (name 'write)
+                                       (default #f)
+                                       (test boolean?)
+                                       (character #f)
+                                       (synopsis "Write the settings to configuration file(s)")
+                                       (description "When this option is present, the configuration values, provided as command line option, will be written to the file path(s) that has/have been specified."))
+                               (setting (name 'port)
+                                        (default 8091)
+                                        (test user-port?)
+                                        (handler string->exact)
+                                        (character #\p)
+                                        (synopsis "Port number that the service will listen on"))
+                               (setting (name 'gn-docs-remote-url)
+                                        (default "git@git.genenetwork.org:/home/git/public/gn-docs")
+                                        (test string?)
+                                        (character #\r)
+                                        (synopsis "Remote URI for gn-docs repository"))
+                               (setting (name 'gn-docs-local-checkout)
+                                        (default (string-append (dirname (getcwd)) "/gn-guile-files/gn-docs"))
+                                        (test file-exists?)
+                                        (character #\c)
+                                        (synopsis "Path where gn-docs is checked out"))
+                               (setting (name 'gn-docs-working-branch)
+                                        (default "non-existent")
+                                        (test string?)
+                                        (character #\b)
+                                        (synopsis "Branch to push/pull from"))))
+                        (parser sexp-parser)
+                        (directory (list (in-home ".config/gn-guile/")
+                                         (in-cwd ".config/"))))))
+    (getopt-config-auto cmd-line config)))
+
+
+(define (cli-options->gn-guile-config cli-options)
+  "Extract specific values from guile-config's <codex> object into gn-guile's custom configuration object."
+  (gn-guile-config
+   (option-ref cli-options 'port)
+   (option-ref cli-options 'gn-docs-remote-url)
+   (option-ref cli-options 'gn-docs-local-checkout)
+   (option-ref cli-options 'gn-docs-working-branch)))
diff --git a/web/webserver.scm b/web/webserver.scm
index 4041f50..891f4f9 100644
--- a/web/webserver.scm
+++ b/web/webserver.scm
@@ -1,4 +1,5 @@
 (use-modules (json)
+             (config)
              (ice-9 match)
              (ice-9 format)
              (ice-9 iconv)
@@ -26,6 +27,7 @@
              (gn data group)
              (gn runner gemma)
              (web sxml)
+             (web config)
              (web view view)
              (web view doc)
              (web view markdown))
@@ -397,6 +399,9 @@ otherwise search for set/group data"
   (write (string-append "Starting Guile REST API " get-version " server!"))
   (write args)
   (newline)
-  (let ((listen (inexact->exact (string->number (car (cdr args))))))
+  (let* ((options (parse-cli-options args))
+         (listen (option-ref options 'port)))
+    (when (option-ref options 'write)
+      (options-write options))
     (display `("listening on" ,listen))
     (start-web-server "127.0.0.1" listen)))