nuke validate knobs with help

openpype/hosts/nuke/plugins/publish/help/validate_knobs.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<root>
+    <error id="main">
+        <title>Knobs value</title>
+        <description>
+## Invalid node's knobs values
+
+Following node knobs needs to be repaired:
+
+### How to repair?
+
+1. Use Repair button.
+2. Hit Reload button on the publisher.
+        </description>
+    </error>
+</root>

openpype/hosts/nuke/plugins/publish/validate_knobs.py

@@ -2,6 +2,7 @@ import nuke
 
 import pyblish.api
 import openpype.api
+from openpype.pipeline import PublishXmlValidationError
 
 
 class ValidateKnobs(pyblish.api.ContextPlugin):
@@ -27,11 +28,12 @@ class ValidateKnobs(pyblish.api.ContextPlugin):
     optional = True
 
     def process(self, context):
-
         invalid = self.get_invalid(context, compute=True)
         if invalid:
-            raise RuntimeError(
-                "Found knobs with invalid values:\n{}".format(invalid)
+            raise PublishXmlValidationError(
+                self,
+                "Found knobs with invalid values:\n{}".format(invalid),
+                formatting_data={}
             )
 
     @classmethod

openpype/hosts/nuke/plugins/publish/validate_write_nodes.py

@@ -76,5 +76,5 @@ class ValidateNukeWriteNode(pyblish.api.InstancePlugin):
                 xml_msg += _msg_add
 
             raise PublishXmlValidationError(
-                self, dbg_msg, {"xml_msg": xml_msg}
+                self, dbg_msg, formatting_data={"xml_msg": xml_msg}
             )