Streaming Response Broken: Integration of Question Classifier with Conditional Logic Before LLM Node

[khoi03]

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Dify version

0.15.3

Cloud or Self Hosted

Self Hosted (Docker)

Steps to reproduce

The LLM's streaming response functionality stops working when implementing a Question Classifier node followed by an If/Else node upstream of the LLM node. While issue #12362 previously addressed streaming problems with If/Else node, the addition of the Question Classifier appears to have reintroduced streaming interruption.

https://github.com/user-attachments/assets/0f360b7a-28fe-49cd-95a0-b62dd57da89a

✔️ Expected Behavior

Streaming Response

❌ Actual Behavior

Blocking Response

[dosubot[bot]]

The issue you're experiencing seems to be related to the integration of the Question Classifier node with the If/Else node, which is affecting the streaming response functionality of the LLM node. While the If/Else node's streaming issues were addressed in Dify version 0.15.2, it appears that the addition of the Question Classifier node has introduced new complications.

Unfortunately, I couldn't find specific information about the implementation or known issues with the Question Classifier node in the Dify codebase. It might be beneficial to check if there are any recent updates or patches related to the Question Classifier node that could address this issue. Additionally, reviewing the logic and configuration of the nodes in your workflow might help identify any potential conflicts or misconfigurations.

If the problem persists, consider reaching out to the Dify community or checking for any ongoing discussions or updates related to this issue in the Dify repository.

To continue talking to Dosu, mention @dosu.

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[zhudongwork]

Another kind of parallel stream output exception of the Question Classifier node. https://github.com/langgenius/dify/issues/15700