[PATCH consfigurator] GPG: handle missing file separately to subprocess errors

[Russell Sim]

When the gpg data source is missing explicitly signal a
MISSING-DATA-SOURCE condition before calling subpocesses.  This makes
the API more consistent with the other data sources.

Signed-off-by: Russell Sim <rsl at simopolis.xyz>
---
 src/data/util.lisp  | 7 +++----
 tests/data/pgp.lisp | 6 ++++++
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/src/data/util.lisp b/src/data/util.lisp
index aa0451f..ef6cb2c 100644
--- a/src/data/util.lisp
+++ b/src/data/util.lisp
@@ -57,8 +57,7 @@ as a string."
 (defun gpg-file-as-string (location)
   "Decrypt the contents of a gpg encrypted file at LOCATION, return as a
 string."
-  (handler-case
+  (if (file-exists-p location)
       (gpg (list "--decrypt" (unix-namestring location)))
-    (subprocess-error (error)
-      (missing-data-source "While attempt to decrypt ~A, gpg exited with ~A"
-			   location (uiop:subprocess-error-code error)))))
+      (missing-data-source "File not found while attempting to decrypt ~A"
+                           location)))
diff --git a/tests/data/pgp.lisp b/tests/data/pgp.lisp
index 21ba60c..a1308bd 100644
--- a/tests/data/pgp.lisp
+++ b/tests/data/pgp.lisp
@@ -19,3 +19,9 @@
 (deftest data.pgp.3
     (get-data-string "host.example.com" "/etc/foo.conf")
   "secret file content")
+
+(deftest data.pgp.4
+    (handler-case (data.pgp:get-data "/tmp/does-not-exist" "_secrets" "test")
+      (missing-data-source (error)
+        (princ-to-string error)))
+  "File not found while attempting to decrypt /tmp/does-not-exist")
-- 
2.37.2