feat: add chat_tui example for FastGPT with Textual interface

- Introduced a new example script `chat_tui.py` that provides a full-screen Textual interface for interacting with FastGPT.
- Implemented streaming chat updates, workflow logging, and modal handling for interactive nodes.
- Enhanced FastGPT client with new streaming capabilities and structured event types for better interaction handling.
- Normalized base URL handling in the client to prevent duplicate `/api` paths.
- Added tests for streaming event parsing and interaction handling.

tests/test_chat_client.py

@@ -12,6 +12,14 @@ from fastgpt_client.exceptions import ValidationError
 class TestChatClientCreateChatCompletion:
     """Test suite for ChatClient.create_chat_completion method."""
 
+    def test_base_url_trailing_api_is_normalized(self, api_key):
+        """A base URL ending with /api should not produce /api/api/... requests."""
+
+        client = ChatClient(api_key, base_url="https://cloud.fastgpt.cn/api")
+
+        assert client.base_url == "https://cloud.fastgpt.cn"
+        assert str(client._client.base_url) == "https://cloud.fastgpt.cn"
+
     def test_create_chat_completion_basic(self, api_key, sample_chat_response):
         """Test basic chat completion creation."""
         client = ChatClient(api_key)

tests/test_streaming.py

@@ -0,0 +1,154 @@
+"""Tests for FastGPT SSE stream parsing helpers."""
+
+import pytest
+
+from fastgpt_client.exceptions import StreamParseError
+from fastgpt_client.streaming import aiter_stream_events, iter_stream_events
+from fastgpt_client.stream_types import FastGPTInteractiveEvent
+
+
+class _AsyncResponse:
+    def __init__(self, lines):
+        self._lines = lines
+
+    async def aiter_lines(self):
+        for line in self._lines:
+            yield line
+
+
+class _SyncResponse:
+    def __init__(self, lines):
+        self._lines = lines
+
+    def iter_lines(self):
+        return iter(self._lines)
+
+
+def test_iter_stream_events_parses_mixed_stream():
+    response = _SyncResponse([
+        'data: {"choices":[{"delta":{"content":"Hel"}}]}',
+        '',
+        'event:flowNodeStatus',
+        'data: {"status":"running","nodeName":"Classifier"}',
+        '',
+        'event:flowResponses',
+        'data: {"moduleName":"Classifier","tokens":4}',
+        '',
+        'event:interactive',
+        'data: {"type":"userSelect","params":{"userSelectOptions":[{"value":"A"}]}}',
+        '',
+        'data: [DONE]',
+        '',
+    ])
+
+    events = list(iter_stream_events(response))
+
+    assert [event.kind for event in events] == [
+        'data',
+        'flowNodeStatus',
+        'flowResponses',
+        'interactive',
+        'done',
+    ]
+    assert isinstance(events[3], FastGPTInteractiveEvent)
+    assert events[3].interaction_type == 'userSelect'
+
+
+def test_iter_stream_events_parses_user_input_interactive():
+    response = _SyncResponse([
+        'event:interactive',
+        'data: {"type":"userInput","params":{"inputForm":[{"label":"Name"}]}}',
+        '',
+    ])
+
+    events = list(iter_stream_events(response))
+
+    assert len(events) == 1
+    assert isinstance(events[0], FastGPTInteractiveEvent)
+    assert events[0].interaction_type == 'userInput'
+
+
+def test_iter_stream_events_unwraps_tool_children_interactive():
+    response = _SyncResponse([
+        'event:interactive',
+        'data: {"interactive":{"type":"toolChildrenInteractive","params":{"childrenResponse":{"type":"userInput","params":{"description":"???????","inputForm":[{"label":"????"}]}}}}}',
+        '',
+    ])
+
+    events = list(iter_stream_events(response))
+
+    assert len(events) == 1
+    assert isinstance(events[0], FastGPTInteractiveEvent)
+    assert events[0].interaction_type == 'userInput'
+    assert events[0].data['params']['description'] == '???????'
+    assert isinstance(events[0].data['params']['inputForm'], list)
+    assert events[0].data['params']['inputForm'][0]['label'] == '????'
+
+
+@pytest.mark.asyncio
+async def test_aiter_stream_events_parses_mixed_stream():
+    response = _AsyncResponse([
+        'data: {"choices":[{"delta":{"content":"Hi"}}]}',
+        '',
+        'event:interactive',
+        'data: {"type":"userSelect","params":{"userSelectOptions":[{"value":"A"}]}}',
+        '',
+        'data: [DONE]',
+        '',
+    ])
+
+    events = []
+    async for event in aiter_stream_events(response):
+        events.append(event)
+
+    assert [event.kind for event in events] == ['data', 'interactive', 'done']
+    assert isinstance(events[1], FastGPTInteractiveEvent)
+
+
+def test_iter_stream_events_rejects_malformed_json():
+    response = _SyncResponse([
+        'event:interactive',
+        'data: {invalid json}',
+        '',
+    ])
+
+    with pytest.raises(StreamParseError):
+        list(iter_stream_events(response))
+
+
+def test_iter_stream_events_rejects_malformed_frame_boundary():
+    response = _SyncResponse([
+        'event:interactive',
+        'event:error',
+        'data: {"message":"bad"}',
+        '',
+    ])
+
+    with pytest.raises(StreamParseError):
+        list(iter_stream_events(response))
+
+
+def test_iter_stream_events_treats_done_marker_under_answer_event_as_done():
+    response = _SyncResponse([
+        'event:answer',
+        'data: [DONE]',
+        '',
+    ])
+
+    events = list(iter_stream_events(response))
+
+    assert [event.kind for event in events] == ['done']
+
+
+def test_iter_stream_events_allows_array_payloads_for_non_interactive_events():
+    response = _SyncResponse([
+        'event:flowResponses',
+        'data: [{"moduleName":"NodeA"},{"moduleName":"NodeB"}]',
+        '',
+    ])
+
+    events = list(iter_stream_events(response))
+
+    assert [event.kind for event in events] == ['flowResponses']
+    assert isinstance(events[0].data, list)
+    assert events[0].data[0]['moduleName'] == 'NodeA'