fix(util): guard _datetime_from_weaviate_str against empty string#2053
Open
devteamaegis wants to merge 1 commit into
Open
fix(util): guard _datetime_from_weaviate_str against empty string#2053devteamaegis wants to merge 1 commit into
devteamaegis wants to merge 1 commit into
Conversation
Empty string is the protobuf wire-format default for an unset string field. Calling string[-1] on "" raises IndexError, crashing gRPC deserialization for any object with an unset date property. Return datetime.min for empty input, matching the existing behaviour for year-zero dates. Fixes weaviate#2052
![orca-security-eu[bot]](https://avatars.githubusercontent.com/in/276244?s=60&v=4){kind=small}
There was a problem hiding this comment.
Orca Security Scan Summary
| Status | Check | Issues by priority | |
|---|---|---|---|
 Passed |
Infrastructure as Code |  0  0  0  0 |
View in Orca |
| Passed |
SAST | 0 0 0 0 |
View in Orca |
| Passed |
Secrets | 0 0 0 0 |
View in Orca |
| Passed |
Vulnerabilities | 0 0 0 0 |
View in Orca |
|
To avoid any confusion in the future about your contribution to Weaviate, we work with a Contributor License Agreement. If you agree, you can simply add a comment to this PR that you agree with the CLA so that we can merge. |
dirkkul
reviewed
Jun 2, 2026
|
|
||
| def _datetime_from_weaviate_str(string: str) -> datetime.datetime: | ||
| if not string: | ||
| return datetime.datetime.min |
Collaborator
There was a problem hiding this comment.
Wouldn't "None" be a better return here?
If we have properties I would expect None if it is unset in Weaviate
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
What's broken
_datetime_from_weaviate_str in weaviate/util.py evaluates string[-1] on line 754 without checking whether string is empty. Python's negative indexing on an empty string raises IndexError. The protobuf wire-format default for a string field is "", so any gRPC query response containing an object with an unset date property crashes the client during deserialization in base_executor.py.
Traceback: IndexError: string index out of range at weaviate/util.py line 754.
Why it happens
The function assumes the input is a non-empty datetime string and immediately indexes from the end, which is invalid for the empty-string protobuf default.
Fix
Added a two-line guard at the top of _datetime_from_weaviate_str: if string is empty, return datetime.min. This matches the existing behaviour for year-zero dates and avoids any semantic change for valid inputs.
Test
Added ("", datetime.min) as a parametrized case in the existing test_datetime_from_weaviate_str test in test/test_util.py. All 40 tests pass.
Fixes #2052