Tool node extract_tool_response_text add empty elements to list

[PedroGomes02]

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Dify version

0.11.2

Cloud or Self Hosted

Self Hosted (Docker)

Steps to reproduce

Use a tool that outputs only more than one ToolInvokeMessage.MessageType.JSON.
Check tool output on tracing. Only the "json" output should be filled, the "text" output should be empty or an empty string.

✔️ Expected Behavior

Only the "json" output should be filled, the "text" output should be empty or an empty string.

❌ Actual Behavior

The "json" output should is filled, but the "text" output is an list of "\n".

[dosubot]

The issue you're experiencing with the extract_tool_response_text function is due to the way the list comprehension is structured in the _extract_tool_response_text method. Specifically, it adds an empty string "" for any ToolInvokeMessage that is not of type TEXT or LINK. This results in a list of empty strings, which when joined with "\n", produces a string of newline characters.

Here's the relevant part of the code:

def _extract_tool_response_text(self, tool_response: list[ToolInvokeMessage]) -> str:
    return "\n".join(
        [
            f"{message.message}"
            if message.type == ToolInvokeMessage.MessageType.TEXT
            else f"Link: {message.message}"
            if message.type == ToolInvokeMessage.MessageType.LINK
            else ""
            for message in tool_response
        ]
    )

The else "" part is responsible for adding empty strings for message types that are neither TEXT nor LINK ^[1].

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