fix(knowledge): 远程 OCR 的「请上传图片」拒绝提示不再作为正文入库

Merged from #867.

CHANGELOG.md

@@ -12,6 +12,7 @@
 - 对话中可隐藏不常用的共享专家（浏览器本地偏好）(#589)
 
 ### 修复
+- 远程 OCR 返回「未收到图片 / 请上传图片」等拒绝提示时不再当作正文入库（此前会被向量化、文档仍标记 ready），现按无可提取文本处理
 - 环境变量值含换行（如粘贴的多行密钥）时，保存后再读取会被截断并残留引号；现按引号跨行读回，保证「写入 → 读取」往返保真
 - 定时任务与系统任务（TLS 自动续期、自动备份）此前按宿主系统时区触发，现按 `default_timezone` 配置时区执行
 

src/octop/infra/knowledge/ocr.py

@@ -5,6 +5,8 @@ from __future__ import annotations
 import asyncio
 import base64
 import json
+import logging
+import re
 import threading
 from collections.abc import Iterator
 from dataclasses import dataclass
@@ -18,6 +20,8 @@ from octop.infra.agents.providers.probe import build_probe_chat_model
 from octop.infra.utils.llm_text import llm_text_content
 from octop.infra.utils.runtime_packages import PackageInstallSpec, install_packages
 
+logger = logging.getLogger(__name__)
+
 OCR_IMAGE_SUFFIXES = frozenset({".png", ".jpg", ".jpeg", ".webp"})
 
 _ENABLED_KEY = "knowledge_ocr_enabled"
@@ -32,6 +36,32 @@ _OCR_PROMPT = (
     "lists, and table rows. Return only the transcription, without commentary."
 )
 
+# A remote vision model that never received the image answers with a refusal such as
+# "No image was attached. Please upload an image.". That is not source text: indexing it
+# poisons the knowledge base and still marks the document ready. Refusals are short and
+# addressed to the caller, so require both a short answer and a refusal phrasing; a real
+# page that merely mentions uploading an image stays well above the length bound.
+_OCR_REFUSAL_MAX_CHARS = 400
+_OCR_REFUSAL_RE = re.compile(
+    r"no image (?:was |is |has been )?(?:attached|provided|found|received|included)"
+    r"|(?:don'?t|do not|can'?t|cannot|unable to|didn'?t) "
+    r"(?:see|find|detect|receive|locate)[^.\n]{0,30}(?:image|picture|photo|scan|attachment)"
+    r"|please (?:attach|upload|provide|send|share)[^.\n]{0,40}"
+    r"(?:image|picture|photo|scan|attachment|file)"
+    r"|未(?:收到|看到|检测到|获取到)[^。\n]{0,10}(?:图片|图像|照片|附件)"
+    r"|请(?:上传|提供|重新上传|发送)[^。\n]{0,10}(?:图片|图像|照片|附件|文件)",
+    re.IGNORECASE,
+)
+
+
+def _is_no_image_refusal(text: str) -> bool:
+    """Return ``True`` when OCR output is the model asking for an image, not a transcription."""
+    stripped = text.strip()
+    if not stripped or len(stripped) > _OCR_REFUSAL_MAX_CHARS:
+        return False
+    return _OCR_REFUSAL_RE.search(stripped) is not None
+
+
 _local_engine: Any | None = None
 _local_engine_lock = threading.Lock()
 
@@ -297,6 +327,15 @@ class _RemoteOcr:
                 ]
             )
             text = llm_text_content(self._model.invoke([message]))
-            if text:
-                parts.append(text)
+            if not text:
+                continue
+            if _is_no_image_refusal(text):
+                # Indexing a refusal would mark the document ready with junk chunks; an empty
+                # result instead fails the document with "no extractable text".
+                logger.warning(
+                    "remote OCR returned a no-image refusal for %s; treating the page as empty",
+                    path.name,
+                )
+                continue
+            parts.append(text)
         return "\n\n".join(parts)

tests/unit/knowledge/test_ocr.py

@@ -154,3 +154,70 @@ def test_remote_ocr_sends_image_block(tmp_path: Path, monkeypatch: pytest.Monkey
     content = messages[0].content
     assert content[1]["type"] == "image_url"
     assert content[1]["image_url"]["url"].startswith("data:image/png;base64,")
+
+
+def _remote_extractor(monkeypatch: pytest.MonkeyPatch, reply: object) -> ocr._RemoteOcr:
+    """Build a ``_RemoteOcr`` whose model returns *reply* (str or a per-call sequence)."""
+
+    class Model:
+        @staticmethod
+        def invoke(_value: list[object]) -> SimpleNamespace:
+            if isinstance(reply, list):
+                return SimpleNamespace(content=reply.pop(0))
+            return SimpleNamespace(content=reply)
+
+    monkeypatch.setattr(ocr, "build_probe_chat_model", lambda *_a, **_k: Model())
+    return ocr._RemoteOcr(SimpleNamespace(), "vision")
+
+
+@pytest.mark.parametrize(
+    "refusal",
+    [
+        "No image was attached. Please upload an image.",
+        "I don't see an image attached to your message. Please upload the image you'd "
+        "like me to transcribe, and I'll provide the exact transcription.",
+        "未收到图片，请上传图片后重试。",
+    ],
+)
+def test_remote_ocr_ignores_no_image_refusal(
+    tmp_path: Path, monkeypatch: pytest.MonkeyPatch, refusal: str
+) -> None:
+    """A refusal is not source text: indexing it would mark the document ready with junk."""
+    image = tmp_path / "scan.png"
+    image.write_bytes(b"image")
+
+    assert _remote_extractor(monkeypatch, refusal)(image) == ""
+
+
+def test_remote_ocr_keeps_long_page_that_mentions_uploading_an_image(
+    tmp_path: Path, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    """The refusal filter must not drop real transcriptions that happen to mention an image."""
+    image = tmp_path / "scan.png"
+    image.write_bytes(b"image")
+    page = (
+        "No image was attached. Please upload an image. "
+        + "发票明细：办公用品 128.00 元，差旅费 340.00 元。" * 12
+    )
+
+    assert _remote_extractor(monkeypatch, page)(image) == page
+
+
+def test_remote_ocr_skips_refusal_page_but_keeps_transcribed_page(
+    tmp_path: Path, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    """Refusals are dropped per page, so a partly readable document keeps its good pages."""
+    pdf = tmp_path / "scan.pdf"
+    pdf.write_bytes(b"%PDF-1.4")
+    monkeypatch.setattr(
+        ocr,
+        "_image_inputs",
+        lambda _path: iter([(b"page-1", "image/png"), (b"page-2", "image/png")]),
+    )
+
+    extractor = _remote_extractor(
+        monkeypatch,
+        ["No image was attached. Please upload an image.", "第二页正文"],
+    )
+
+    assert extractor(pdf) == "第二页正文"