1 files changed, 61 insertions, 0 deletions
diff --git a/src/validators/file-exists b/src/validators/file-exists
new file mode 100755
index 000000000..5cef6b199
--- /dev/null
+++ b/src/validators/file-exists
@@ -0,0 +1,61 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2019 VyOS maintainers and contributors
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 or later as
+# published by the Free Software Foundation.
+#
+# This program 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/>.
+#
+# Description:
+# Check if a given file exists on the system. Used for files that
+# are referenced from the CLI and need to be preserved during an image upgrade.
+# Warn the user if these aren't under /config
+
+import os
+import sys
+import argparse
+
+
+def exit(strict, message):
+    if strict:
+        sys.exit(f'ERROR: {message}')
+    print(f'WARNING: {message}', file=sys.stderr)
+    sys.exit()
+
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser()
+    parser.add_argument("-d", "--directory", type=str, help="File must be present in this directory.")
+    parser.add_argument("-e", "--error", action="store_true", help="Tread warnings as errors - change exit code to '1'")
+    parser.add_argument("file", type=str, help="Path of file to validate")
+
+    args = parser.parse_args()
+
+    #
+    # Always check if the given file exists
+    #
+    if not os.path.exists(args.file):
+        exit(args.error, f"File '{args.file}' not found")
+
+    #
+    # Optional check if the file is under a certain directory path
+    #
+    if args.directory:
+        # remove directory path from path to verify
+        rel_filename = args.file.replace(args.directory, '').lstrip('/')
+
+        if not os.path.exists(args.directory + '/' + rel_filename):
+            exit(args.error,
+                f"'{args.file}' lies outside of '{args.directory}' directory.\n"
+                  "It will not get preserved during image upgrade!"
+            )
+
+    sys.exit()