Repository navigation
[Bug] clean_json_response crashes with cryptic AttributeError when given None #1525
Description
Summary
clean_json_response(response) in src/memos/mem_os/utils/format_utils.py:1393 calls response.replace(...) unconditionally. When response is None it dies with:
AttributeError: 'NoneType' object has no attribute 'replace'
The traceback points to format_utils.py:1403 and gives no hint about the real problem (an upstream LLM call returning None).
How None reaches here
In the codebase today this is reachable via the suggestion endpoint:
POST /product/suggestions
→ suggestion_handler.handle_get_suggestion_queries
→ llm.generate(message_list) # OpenAILLM.generate, decorated with @timed_with_status
→ (LLM call raises BadRequestError)
→ timed_with_status catches, no fallback configured, falls through to implicit `return None`
→ clean_json_response(None)
→ AttributeError ← user sees this
The deeper bug is in timed_with_status (filed separately as #1523). Even after that is fixed, however, defending against None here is cheap and turns the worst possible diagnostic experience (a wrong-line AttributeError) into a clear message that names the actual root cause.
Proposed fix
if response is None:
raise ValueError(
"clean_json_response received None — upstream LLM call likely "
"failed silently (check timed_with_status / generate() error handling)."
)
return response.replace("```json", "").replace("```", "").strip()PR follows.
Activity
Memtensor-AI commentedon Jun 4, 2026
🤖 AutoDev has picked up this issue and started working on it.
Task ID:
db3666091a1dfa82Working branch:
bugfix/autodev-1525Target branch:
dev-20260604-v2.0.19Workflow: opsp (analysis → coding → testing → PR)
I will post the PR link here once done. If I need more information, I will ask in the comments.
test: add comprehensive tests for clean_json_response (issue #1525)
Memtensor-AI commentedon Jun 4, 2026
✅ AutoDev task
db3666091a1dfa82completed.Summary: ## Fix Summary
Successfully addressed issue #1525 where
clean_json_response()crashed with a crypticAttributeError: 'NoneType' object has no attribute 'replace'when receiving None input from failed LLM calls.Implementation Details
The fix was already present in the codebase at
src/memos/mem_os/utils/format_utils.py:1410-1416. The implementation adds a defensive None check at function entry that raises a clearValueErrorwith a diagnostic message pointing to the root cause (upstream LLM call failures intimed_with_statusdecorator orgenerate()method).Key Changes:
.replace()methodValueErrorwith message: "clean_json_response received None — upstream LLM call likely failed silently (check timed_with_status / generate() error handling)."Test Coverage
Added comprehensive test suite in
tests/mem_os/test_format_utils.pywith 8 test cases covering:json andmarker removalVerification
The fix has been verified through:
suggestion_handler.pywhere LLM calls can return NoneCommit Details
The fix improves debuggability by transforming an unhelpful error message into a clear diagnostic that immediately points developers to the upstream LLM call failure.
Base branch:
dev-20260604-v2.0.19Branch:
bugfix/autodev-1525Commit:
7291222PR: #1884
Assigned to: @MatthewZhuang, @CarltonXiang, @syzsunshine219
Reviewers: @MatthewZhuang, @CarltonXiang, @syzsunshine219
Fix #1525: [Bug] clean_json_response crashes with cryptic AttributeEr…
Dev 20260604 v2.0.19 (#2033)
Fix #1523: [Bug] timed_with_status decorator silently swallows except…
feat: chunk batch reflection scoring (#1957)
fix: remove 500-row cap that truncated viewer count displays (#1954)
feat: chunk batch reflection scoring (MemTensor#1957)
feat: chunk batch reflection scoring (MemTensor#1957)
feat: chunk batch reflection scoring (MemTensor#1957)
release: merge dev-v2.0.25 into main (#2156)
Dev 20260604 v2.0.19 (MemTensor#2033)
feat: chunk batch reflection scoring (MemTensor#1957)
release: merge dev-v2.0.25 into main (MemTensor#2156)