From 6e1769750ebcd8430528b17fc60df3eb6ec11d92 Mon Sep 17 00:00:00 2001
From: Khor Shu Heng <32997938+khorshuheng@users.noreply.github.com>
Date: Tue, 16 Apr 2024 15:50:40 +0800
Subject: [PATCH] bugfix: handle empty feature orders list (#571)

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# Description
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illustrations where appropriate. -->
The observation publisher is failing after the introduction of feature
orders field, because it was assumed that the feature orders is either
None or a list with one or more elements.

# Modifications
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# Tests
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- [ ] Deploying PyFunc models
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# Checklist
- [ ] Added PR label
- [ ] Added unit test, integration, and/or e2e tests
- [ ] Tested locally
- [ ] Updated documentation
- [ ] Update Swagger spec if the PR introduce API changes
- [ ] Regenerated Golang and Python client if the PR introduces API
changes

# Release Notes
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```release-note

```
---
 python/observation-publisher/publisher/prediction_log_parser.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/python/observation-publisher/publisher/prediction_log_parser.py b/python/observation-publisher/publisher/prediction_log_parser.py
index 12893cb49..786f276b1 100644
--- a/python/observation-publisher/publisher/prediction_log_parser.py
+++ b/python/observation-publisher/publisher/prediction_log_parser.py
@@ -27,7 +27,7 @@ def from_struct(
         :param inference_schema: Model inference schema.
         :return: Instance of PredictionLogFeatureTable.
         """
-        if inference_schema.feature_orders is not None:
+        if inference_schema.feature_orders is not None and len(inference_schema.feature_orders) > 0:
             columns = inference_schema.feature_orders
         else:
             assert isinstance(table_struct["columns"], ListValue)