The temprary "session" collection might not exist in Secret Service

* doc/misc/auth.texi (Secret Service API):
* test/lisp/net/secrets-tests.el (secrets--test-delete-all-session-items)
(secrets-test02-collections, secrets-test03-items)
(secrets-test04-search): The temporary "session" collection might
not exist.

* lisp/net/secrets.el (secrets-struct-secret-content-type):
Remove compatibility hack.
(secrets-create-item): Adapt accordingly.

3 files changed, 20 insertions, 48 deletions

diff --git a/doc/misc/auth.texi b/doc/misc/auth.texi
index 034004d1df4..6602f9dc2e4 100644
--- a/doc/misc/auth.texi
+++ b/doc/misc/auth.texi
@@ -370,6 +370,10 @@ items should not live longer than Emacs.  The session collection can
 be specified either by the string @code{"session"}, or by @code{nil},
 whenever a collection parameter is needed in the following functions.
 
+However, not all Secret Service provider create this temporary
+@code{"session"} collection, like KeePassXC.  You shall check first
+that this collection exists, before you use it.
+
 @defun secrets-list-items collection
 Returns all the item labels of @var{collection} as a list.
 @end defun
@@ -382,7 +386,7 @@ pairs set for the created item.  The keys are keyword symbols,
 starting with a colon.  Example:
 
 @example
-;;; The session is "session", the label is "my item"
+;;; The collection is "session", the label is "my item"
 ;;; and the secret (password) is "geheim".
 (secrets-create-item "session" "my item" "geheim"
  :method "sudo" :user "joe" :host "remote-host")
diff --git a/lisp/net/secrets.el b/lisp/net/secrets.el
index 4217c219ad9..25802f2c463 100644
--- a/lisp/net/secrets.el
+++ b/lisp/net/secrets.el
@@ -263,6 +263,7 @@ It returns t if not."
 ;;   </signal>
 ;; </interface>
 
+;; This is not guaranteed to exist.  For example, KeePassXC does not offer this.
 (defconst secrets-session-collection-path
   "/org/freedesktop/secrets/collection/session"
   "The D-Bus temporary session collection object path.")
@@ -311,43 +312,8 @@ It returns t if not."
 (defconst secrets-interface-item-type-generic "org.freedesktop.Secret.Generic"
   "The default item type we are using.")
 
-;; We cannot use introspection, because some servers, like
-;; mate-keyring-daemon, don't provide relevant data.  Once the dust
-;; has settled, we shall assume the new interface, and get rid of the test.
-(defconst secrets-struct-secret-content-type
-  (ignore-errors
-    (let ((content-type "text/plain")
-          (path (cadr
-                 (dbus-call-method
-                  :session secrets-service secrets-path
-                  secrets-interface-service
-                  "OpenSession" "plain" '(:variant ""))))
-          result)
-      ;; Create a dummy item.
-      (setq result
-            (dbus-call-method
-             :session secrets-service secrets-session-collection-path
-             secrets-interface-collection "CreateItem"
-             ;; Properties.
-             `(:array
-               (:dict-entry ,(concat secrets-interface-item ".Label")
-                            (:variant " ")))
-             ;; Secret.
-             `(:struct :object-path ,path
-                       (:array :signature "y")
-                       ,(dbus-string-to-byte-array " ")
-                       :string ,content-type)
-             ;; Don't replace.
-             nil))
-      ;; Remove it.
-      (dbus-call-method
-       :session secrets-service (car result)
-       secrets-interface-item "Delete")
-      ;; Result.
-      `(,content-type)))
-  "The content_type of a secret struct.
-It must be wrapped as list, because we add it via `append'.  This
-is an interface introduced in 2011.")
+(defconst secrets-struct-secret-content-type "text/plain"
+  "The content_type of a secret struct.")
 
 (defconst secrets-interface-session "org.freedesktop.Secret.Session"
   "A session tracks state between the service and a client application.")
@@ -696,13 +662,10 @@ The object path of the created item is returned."
                 `((:dict-entry ,(concat secrets-interface-item ".Attributes")
                                (:variant ,(append '(:array) props))))))
              ;; Secret.
-             (append
-              `(:struct :object-path ,secrets-session-path
-                        (:array :signature "y") ;; No parameters.
-                        ,(dbus-string-to-byte-array password))
-              ;; We add the content_type.  In backward compatibility
-              ;; mode, nil is appended, which means nothing.
-              secrets-struct-secret-content-type)
+             `(:struct :object-path ,secrets-session-path
+                       (:array :signature "y") ;; No parameters.
+                       ,(dbus-string-to-byte-array password)
+                       ,secrets-struct-secret-content-type)
              ;; Do not replace. Replace does not seem to work.
              nil))
       (secrets-prompt (cadr result))
diff --git a/test/lisp/net/secrets-tests.el b/test/lisp/net/secrets-tests.el
index b392c4d1847..03d3e26faa6 100644
--- a/test/lisp/net/secrets-tests.el
+++ b/test/lisp/net/secrets-tests.el
@@ -57,8 +57,11 @@
 
 (defun secrets--test-delete-all-session-items ()
   "Delete all items of collection \"session\" bound to this Emacs."
-  (dolist (item (secrets-list-items "session"))
-    (secrets-delete-item "session" item)))
+  ;; If the "session" collection does not exist, a `dbus-error' is
+  ;; fired, which we ignore.
+  (dbus-ignore-errors
+    (dolist (item (secrets-list-items "session"))
+      (secrets-delete-item "session" item))))
 
 (ert-deftest secrets-test01-sessions ()
   "Test opening / closing a secrets session."
@@ -93,7 +96,7 @@
   (unwind-protect
       (progn
         (should (secrets-open-session))
-        (should (member "session" (secrets-list-collections)))
+        (skip-unless (member "session" (secrets-list-collections)))
 
         ;; Create a random collection.  This asks for a password
         ;; outside our control, so we make it in the interactive case
@@ -153,6 +156,7 @@
   (unwind-protect
       (let (item-path)
         (should (secrets-open-session))
+        (skip-unless (member "session" (secrets-list-collections)))
 
         ;; Cleanup.  There could be items in the "session" collection.
         (secrets--test-delete-all-session-items)
@@ -214,6 +218,7 @@
   (unwind-protect
       (progn
         (should (secrets-open-session))
+        (skip-unless (member "session" (secrets-list-collections)))
 
         ;; Cleanup.  There could be items in the "session" collection.
         (secrets--test-delete-all-session-items)