add :LOCAL-FILE data source

Signed-off-by: Sean Whitton <spwhitton@spwhitton.name>

1 files changed, 39 insertions, 0 deletions

diff --git a/src/data/local-file.lisp b/src/data/local-file.lisp
new file mode 100644
index 0000000..080c0da
--- /dev/null
+++ b/src/data/local-file.lisp
@@ -0,0 +1,39 @@
+;;; Consfigurator -- Lisp declarative configuration management system
+
+;;; Copyright (C) 2021  Sean Whitton <spwhitton@spwhitton.name>
+
+;;; This file 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, or (at your option)
+;;; any later version.
+
+;;; This file 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+
+(in-package :consfigurator.data.git-snapshot)
+(named-readtables:in-readtable :consfigurator)
+
+(defmethod register-data-source
+    ((type (eql :local-file)) &key file version iden1 iden2)
+  "Provide the contents of a single local file on the machine running the root
+Lisp.  Register this data source more than once to provide multiple files.
+The version of the data provided is either VERSION or the file's last
+modification time."
+  (unless (file-exists-p file)
+    (missing-data-source "~A does not exist." file))
+  (cons (lambda (iden1* iden2*)
+          (and (string= iden1 iden1*) (string= iden2 iden2*)
+               (file-exists-p file)
+               (or version (file-write-date file))))
+        (lambda (iden1* iden2*)
+          (and (string= iden1 iden1*) (string= iden2 iden2*)
+               (file-exists-p file)
+               (make-instance 'file-data
+                              :file file
+                              :iden1 iden1 :iden2 iden2
+                              :version (or version (file-write-date file)))))))