fix(kb): 当 markitdown 不可用时，回退到纯文本解析器处理 txt/md 文件 | fall back to plain-text parser for txt/md when markitdown is unavailable

astrbot/core/knowledge_base/kb_helper.py

@@ -282,6 +282,17 @@ async def upload_document(
                     parse_result = await parser.parse(file_content, file_name)
                 except KnowledgeBaseUploadError:
                     raise
+                except ModuleNotFoundError as exc:
+                    if exc.name == "markitdown_no_magika":
+                        raise KnowledgeBaseUploadError(
+                            stage="parsing",
+                            user_message=(
+                                "文档解析失败：缺少解析该文件格式所需的依赖"
+                                " markitdown-no-magika，请安装后重试。"
+                            ),
+                            details={"file_name": file_name},
+                        ) from exc
+                    raise
                 except Exception as exc:
                     raise KnowledgeBaseUploadError(
                         stage="parsing",

astrbot/core/knowledge_base/parsers/util.py

@@ -2,7 +2,11 @@
 
 
 async def select_parser(ext: str) -> BaseParser:
-    if ext in {".md", ".txt", ".markdown", ".rst", ".adoc", ".xlsx", ".docx", ".xls"}:
+    if ext in {".txt", ".md", ".markdown"}:
+        from .text_parser import TextParser
+
+        return TextParser()
+    if ext in {".rst", ".adoc", ".xlsx", ".docx", ".xls"}:
         from .markitdown_parser import MarkitdownParser
 
         return MarkitdownParser()

tests/unit/test_kb_select_parser.py

@@ -0,0 +1,167 @@
+"""
+Unit tests for knowledge base parser selection and missing-dependency errors.
+
+Covers:
+1. .txt / .md / .markdown are routed to the stdlib TextParser (no third-party
+   dependency required), so plain-text uploads work without markitdown.
+2. .rst / .adoc keep routing to MarkitdownParser (requires markitdown).
+3. upload_document surfaces a clear missing-dependency message when
+   markitdown-no-magika is absent, instead of the generic parse failure.
+4. A missing unrelated module (e.g. pypdf) is not mislabeled as a markitdown
+   problem.
+"""
+
+import sys
+import types
+from pathlib import Path
+from unittest.mock import AsyncMock, MagicMock, patch
+
+import pytest
+
+from astrbot.core.exceptions import KnowledgeBaseUploadError
+from astrbot.core.knowledge_base.models import KnowledgeBase
+from astrbot.core.knowledge_base.parsers.text_parser import TextParser
+from astrbot.core.knowledge_base.parsers.util import select_parser
+
+
+@pytest.fixture
+def stub_provider_manager_module():
+    """Stub provider manager module to avoid circular imports in unit tests."""
+    original_module = sys.modules.get("astrbot.core.provider.manager")
+    stub_module = types.ModuleType("astrbot.core.provider.manager")
+
+    class ProviderManager: ...
+
+    setattr(stub_module, "ProviderManager", ProviderManager)
+    sys.modules["astrbot.core.provider.manager"] = stub_module
+
+    # Drop already-imported modules that transitively need ProviderManager so
+    # they re-import against the stub.
+    to_drop = [
+        name
+        for name in list(sys.modules)
+        if name.startswith("astrbot.core.knowledge_base.kb_helper")
+        or name.startswith("astrbot.core.knowledge_base.kb_mgr")
+    ]
+    for name in to_drop:
+        sys.modules.pop(name, None)
+
+    try:
+        yield
+    finally:
+        if original_module is not None:
+            sys.modules["astrbot.core.provider.manager"] = original_module
+        else:
+            sys.modules.pop("astrbot.core.provider.manager", None)
+
+
+def _import_kb_helper():
+    from astrbot.core.knowledge_base.kb_helper import KBHelper
+
+    return KBHelper
+
+
+@pytest.mark.asyncio
+@pytest.mark.parametrize("ext", [".txt", ".md", ".markdown"])
+async def test_select_parser_routes_plain_text_to_text_parser(ext):
+    parser = await select_parser(ext)
+
+    assert isinstance(parser, TextParser)
+
+
+@pytest.mark.asyncio
+@pytest.mark.parametrize("ext", [".rst", ".adoc"])
+async def test_select_parser_keeps_markup_formats_on_markitdown(ext):
+    pytest.importorskip("markitdown_no_magika")
+
+    from astrbot.core.knowledge_base.parsers.markitdown_parser import MarkitdownParser
+
+    parser = await select_parser(ext)
+
+    assert isinstance(parser, MarkitdownParser)
+
+
+@pytest.mark.asyncio
+async def test_text_parser_decodes_plain_text_file():
+    result = await TextParser().parse("你好 world\nsecond line".encode(), "note.txt")
+    assert result.media == []
+    assert result.text == "你好 world\nsecond line"
+
+    gbk_result = await TextParser().parse("中文内容".encode("gbk"), "note.txt")
+    assert gbk_result.text == "中文内容"
+
+
+def _make_upload_helper(tmp_path: Path):
+    KBHelper = _import_kb_helper()
+
+    helper = KBHelper.__new__(KBHelper)
+    helper.kb = KnowledgeBase(
+        kb_name="Test KB",
+        description="",
+        embedding_provider_id="emb",
+    )
+    helper.kb_db = MagicMock()
+    helper.vec_db = AsyncMock()
+    helper.vec_db.delete_documents = AsyncMock()
+    helper.kb_medias_dir = tmp_path / "medias"
+    helper.chunker = AsyncMock()
+    return helper
+
+
+@pytest.mark.asyncio
+async def test_upload_document_reports_missing_markitdown_dependency(
+    tmp_path: Path,
+    stub_provider_manager_module,
+) -> None:
+    helper = _make_upload_helper(tmp_path)
+
+    with (
+        patch(
+            "astrbot.core.knowledge_base.kb_helper.select_parser",
+            new=AsyncMock(
+                side_effect=ModuleNotFoundError(
+                    "No module named 'markitdown_no_magika'",
+                    name="markitdown_no_magika",
+                ),
+            ),
+        ),
+        patch.object(helper, "_ensure_vec_db", new=AsyncMock()),
+        pytest.raises(KnowledgeBaseUploadError) as exc_info,
+    ):
+        await helper.upload_document(
+            file_name="guide.docx",
+            file_content=b"fake",
+            file_type="docx",
+        )
+
+    assert exc_info.value.stage == "parsing"
+    assert "markitdown-no-magika" in exc_info.value.user_message
+
+
+@pytest.mark.asyncio
+async def test_upload_document_passes_through_unrelated_missing_module(
+    tmp_path: Path,
+    stub_provider_manager_module,
+) -> None:
+    helper = _make_upload_helper(tmp_path)
+
+    with (
+        patch(
+            "astrbot.core.knowledge_base.kb_helper.select_parser",
+            new=AsyncMock(
+                side_effect=ModuleNotFoundError(
+                    "No module named 'pypdf'",
+                    name="pypdf",
+                ),
+            ),
+        ),
+        patch.object(helper, "_ensure_vec_db", new=AsyncMock()),
+        pytest.raises(ModuleNotFoundError) as exc_info,
+    ):
+        await helper.upload_document(
+            file_name="guide.pdf",
+            file_content=b"fake",
+            file_type="pdf",
+        )
+
+    assert exc_info.value.name == "pypdf"