confd: Add mount constraint for container config

This change ensures configuration correctness by enforcing that each
  container mount has either a source or content set. Without this, the
  system may generate invalid runtime arguments (src=(null)), leading
  to container startup failures.

doc/ChangeLog.md

@@ -20,6 +20,7 @@ All notable changes to the project are documented in this file.
 ### Fixes
 - Fix containers with multiple mounts
 - Correct description for LAG LACP modes 
+- Fix #1040: Add `mount` constraint for container config 
 
 
 [v25.04.0][] - 2025-04-30

src/confd/yang/confd/infix-containers.yang

@@ -22,6 +22,13 @@ module infix-containers {
     prefix infix-sys;
   }
 
+  revision 2025-05-14 {
+    description
+      "Validation improvement:
+       - Added constraint to require either 'source' or 'content' in a container mount.";
+    reference "internal";
+  }
+
   revision 2024-11-15 {
     description "Two major changes:
                   - Add support for ftp/http/https images with checksum
@@ -342,6 +349,7 @@ module infix-containers {
         }
 
         choice data {
+          mandatory true;
           case source {
             leaf source {
               description "Host path to mount in container, may be a glob.

src/confd/yang/containers.inc

@@ -2,5 +2,5 @@
 # REMEMBER TO UPDATE infix-interfaces ALSO IN confd.inc
 MODULES=(
     "infix-interfaces@2025-01-09.yang -e vlan-filtering -e containers"
-    "infix-containers@2024-11-15.yang"
+    "infix-containers@2025-05-14.yang"
 )