From 9065204e95b964e76b4ea1beebca55933eab7549 Mon Sep 17 00:00:00 2001
From: Ondrej Samohel <ondrej.samohel@orbi.tools>
Date: Fri, 15 Oct 2021 01:32:20 +0200
Subject: [PATCH] subset check and documentation

---
 openpype/hosts/houdini/api/plugin.py          |  3 ++-
 .../houdini/plugins/create/create_hda.py      | 24 ++++++++++--------
 website/docs/artist_hosts_houdini.md          | 25 +++++++++++++++++++
 3 files changed, 41 insertions(+), 11 deletions(-)

diff --git a/openpype/hosts/houdini/api/plugin.py b/openpype/hosts/houdini/api/plugin.py
index efdaa60084..63d9bba470 100644
--- a/openpype/hosts/houdini/api/plugin.py
+++ b/openpype/hosts/houdini/api/plugin.py
@@ -1,6 +1,7 @@
 # -*- coding: utf-8 -*-
 """Houdini specific Avalon/Pyblish plugin definitions."""
 import sys
+from avalon.api import CreatorError
 from avalon import houdini
 import six
 
@@ -8,7 +9,7 @@ import hou
 from openpype.api import PypeCreatorMixin
 
 
-class OpenPypeCreatorError(Exception):
+class OpenPypeCreatorError(CreatorError):
     pass
 
 
diff --git a/openpype/hosts/houdini/plugins/create/create_hda.py b/openpype/hosts/houdini/plugins/create/create_hda.py
index 775c51166a..63d235d235 100644
--- a/openpype/hosts/houdini/plugins/create/create_hda.py
+++ b/openpype/hosts/houdini/plugins/create/create_hda.py
@@ -22,12 +22,13 @@ class CreateHDA(plugin.Creator):
         # type: (str) -> bool
         """Check if existing subset name versions already exists."""
         # Get all subsets of the current asset
+        asset_id = io.find_one({"name": self.data["asset"], "type": "asset"},
+                               projection={"_id": True})['_id']
         subset_docs = io.find(
             {
                 "type": "subset",
-                "parent": self.data["asset"]
-            },
-            {"name": 1}
+                "parent": asset_id
+            }, {"name": 1}
         )
         existing_subset_names = set(subset_docs.distinct("name"))
         existing_subset_names_low = {
@@ -36,7 +37,7 @@ class CreateHDA(plugin.Creator):
         return subset_name.lower() in existing_subset_names_low
 
     def _process(self, instance):
-
+        subset_name = self.data["subset"]
         # get selected nodes
         out = hou.node("/obj")
         self.nodes = hou.selectedNodes()
@@ -60,26 +61,29 @@ class CreateHDA(plugin.Creator):
         if not to_hda.type().definition():
             # if node type has not its definition, it is not user
             # created hda. We test if hda can be created from the node.
-
             if not to_hda.canCreateDigitalAsset():
                 raise Exception(
                     "cannot create hda from node {}".format(to_hda))
 
             hda_node = to_hda.createDigitalAsset(
-                name=self.name,
-                hda_file_name="$HIP/{}.hda".format(self.name)
+                name=subset_name,
+                hda_file_name="$HIP/{}.hda".format(subset_name)
             )
             hou.moveNodesTo(self.nodes, hda_node)
             hda_node.layoutChildren()
         else:
+            if self._check_existing(subset_name):
+                raise plugin.OpenPypeCreatorError(
+                        ("subset {} is already published with different HDA"
+                         "definition.").format(subset_name))
             hda_node = to_hda
 
-        hda_node.setName(self.name)
+        hda_node.setName(subset_name)
 
         # delete node created by Avalon in /out
         # this needs to be addressed in future Houdini workflow refactor.
 
-        hou.node("/out/{}".format(self.name)).destroy()
+        hou.node("/out/{}".format(subset_name)).destroy()
 
         try:
             lib.imprint(hda_node, self.data)
@@ -89,4 +93,4 @@ class CreateHDA(plugin.Creator):
                  "OpenPype asset.")
             )
 
-        return hda_node
\ No newline at end of file
+        return hda_node
diff --git a/website/docs/artist_hosts_houdini.md b/website/docs/artist_hosts_houdini.md
index d2aadf05cb..bd422b046e 100644
--- a/website/docs/artist_hosts_houdini.md
+++ b/website/docs/artist_hosts_houdini.md
@@ -76,3 +76,28 @@ I've selected `vdb1` and went **OpenPype -> Create** and selected **VDB Cache**.
 geometry ROP in `/out` and sets its paths to output vdb files. During the publishing process
 whole dops are cooked.
 
+## Publishing Houdini Digital Assets (HDA)
+
+You can publish most of the nodes in Houdini as hda for easy interchange of data between Houdini instances or even
+other DCCs with Houdini Engine.
+
+## Creating HDA
+
+Simply select nodes you want to include in hda and go **OpenPype -> Create** and select **Houdini digital asset (hda)**.
+You can even use already existing hda as a selected node, and it will be published (see below for limitation).
+
+:::caution HDA Workflow limitations
+As long as the hda is of same type - it is created from different nodes but using the same (subset) name, everything
+is ok. But once you've published version of hda subset, you cannot change its type. For example, you create hda **Foo**
+from *Cube* and *Sphere* - it will create hda subset named `hdaFoo` with the same type. You publish it as version 1.
+Then you create version 2 with added *Torus*. Then you create version 3 from the scratch from completely different nodes,
+but still using resulting subset name `hdaFoo`. Everything still works as expected. But then you use already
+existing hda as a base, for example from different artist. Its type cannot be changed from what it was and so even if
+it is named `hdaFoo` it has different type. It could be published, but you would never load it and retain ability to
+switch versions between different hda types.
+:::
+
+## Loading HDA
+
+When you load hda, it will install its type in your hip file and add published version as its definition file. When
+you  switch version via Scene Manager, it will add its definition and set it as preferred.
\ No newline at end of file