modified validator if not existing paths as there is a chance that filepaths are not filled at all

openpype/hosts/traypublisher/plugins/publish/validate_filepaths.py

@@ -3,8 +3,17 @@ import pyblish.api
 from openpype.pipeline import PublishValidationError
 
 
-class ValidateWorkfilePath(pyblish.api.InstancePlugin):
-    """Validate existence of workfile instance existence."""
+class ValidateFilePath(pyblish.api.InstancePlugin):
+    """Validate existence of source filepaths on instance.
+
+    Plugins looks into key 'sourceFilepaths' and validate if paths there
+    actually exist on disk.
+
+    Also validate if the key is filled but is empty. In that case also
+    crashes so do not fill the key if unfilled value should not cause error.
+
+    This is primarily created for Simple Creator instances.
+    """
 
     label = "Validate Workfile"
     order = pyblish.api.ValidatorOrder - 0.49
@@ -14,12 +23,24 @@ class ValidateWorkfilePath(pyblish.api.InstancePlugin):
     def process(self, instance):
         if "sourceFilepaths" not in instance.data:
             self.log.info((
-                "Can't validate source filepaths existence."
+                "Skipped validation of source filepaths existence."
                 " Instance does not have collected 'sourceFilepaths'"
             ))
             return
 
-        filepaths = instance.data.get("sourceFilepaths")
+        filepaths = instance.data["sourceFilepaths"]
+        if not filepaths:
+            raise PublishValidationError(
+                (
+                    "Source filepaths of '{}' instance \"{}\" are not filled"
+                ).format(instance.data["family"], instance.data["name"]),
+                "File not filled",
+                (
+                    "## Files were not filled"
+                    "\nThis could mean that you didn't enter files into file"
+                    "input."
+                )
+            )
 
         not_found_files = [
             filepath