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toy0116
8955bf1aa8
Reproduce:
1. Run WeKnora pointing OPENAI_BASE_URL at any OpenAI-compatible
embedding endpoint.
2. Stop that endpoint.
3. Issue any RAG-mode chat / knowledge_search query — the pipeline
reaches chunk_search_parallel → knowledgeBaseService.GetQueryEmbedding
→ OpenAIEmbedder.Embed → OpenAIEmbedder.BatchEmbed.
4. Observe the entire WeKnora process SIGSEGV instead of returning a
graceful 5xx.
Stack (real, observed in production):
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x2 addr=0x40]
internal/models/embedding/openai.go:195 +0x458 BatchEmbed
internal/models/embedding/openai.go:93 +0xb0 Embed
internal/application/service/knowledgebase_search.go:35
GetQueryEmbedding
internal/application/service/chat_pipeline/search.go:371
searchByTargets.func1
Root cause — variable shadowing in doRequestWithRetry:
func (e *OpenAIEmbedder) doRequestWithRetry(...) (*http.Response, error) {
var resp *http.Response
var err error // outer err
...
for i := 0; i <= e.maxRetries; i++ {
...
req, err := http.NewRequestWithContext(...) // ← `:=` shadows
// outer `err`
// because `req`
// is new in
// the loop scope
if err != nil { ... continue }
...
resp, err = e.httpClient.Do(req) // writes to the
// shadowed
// loop-local err
if err == nil { return resp, nil }
logger.Errorf("attempt %d failed: %v", i+1, err) // logs the inner err
}
return nil, err // returns OUTER
// err — never set
}
When httpClient.Do returns connection errors on every attempt, the loop
logs them faithfully but the outer err stays nil. The function returns
(nil, nil). Caller in BatchEmbed reads:
resp, err := e.doRequestWithRetry(ctx, jsonData)
if err != nil { return nil, ... } // skipped (err is nil)
if resp.Body != nil { // ← line 195 · resp itself is nil
defer resp.Body.Close() // nil pointer dereference
} // → SIGSEGV → process dies
Fix — declare `req` separately so the shared `err` variable is not shadowed:
var req *http.Request
req, err = http.NewRequestWithContext(...) // outer err
After the fix, when all retries fail, doRequestWithRetry returns the real
error (e.g. `dial tcp 127.0.0.1:11434: connect: connection refused`),
the caller propagates it as a regular error, the chat pipeline returns a
5xx to the client, and the process keeps running.
Verified by stopping the embedding upstream while WeKnora was serving
queries · process stayed up · returned graceful errors · resumed normal
operation when the upstream came back. Without the patch the same
sequence killed the process within one query.