From 2520ceca630d5985a9646e0002aaea352445cfd0 Mon Sep 17 00:00:00 2001
From: Roy Nieterau <roy_nieterau@hotmail.com>
Date: Wed, 30 Mar 2022 22:12:00 +0200
Subject: [PATCH] Fix #2946: Avoid ImportError on `hdefereval` when Houdini
 runs without UI

---
 openpype/hosts/houdini/api/pipeline.py | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/openpype/hosts/houdini/api/pipeline.py b/openpype/hosts/houdini/api/pipeline.py
index d079c9ea81..31c82b1cfd 100644
--- a/openpype/hosts/houdini/api/pipeline.py
+++ b/openpype/hosts/houdini/api/pipeline.py
@@ -4,7 +4,6 @@ import logging
 import contextlib
 
 import hou
-import hdefereval
 
 import pyblish.api
 import avalon.api
@@ -305,7 +304,13 @@ def on_new():
         start = hou.playbar.playbackRange()[0]
         hou.setFrame(start)
 
-    hdefereval.executeDeferred(_enforce_start_frame)
+    if hou.isUIAvailable():
+        import hdefereval
+        hdefereval.executeDeferred(_enforce_start_frame)
+    else:
+        # Run without execute deferred when no UI is available because
+        # without UI `hdefereval` is not available to import
+        _enforce_start_frame()
 
 
 def _set_context_settings():