fix: Preflight-Check und Exit-Code in --once Modus (v0.2.1)

- #1: check_preflight() prüft beim Start tesseract + gs, wirft
  PreflightError. CLI endet mit Exit 2 statt grün zu bleiben.
- #2: run_once() gibt Anzahl fehlgeschlagener PDFs zurück, CLI
  endet mit Exit 1 wenn mindestens eine Datei scheiterte.
- pytest-Suite mit 11 Tests für beide Szenarien
- ocrmypdf-Import lazy in processor.py (Tests ohne ocrmypdf möglich)

Closes #1, #2

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.gitignore

@@ -4,6 +4,7 @@ __pycache__/
 venv/
 env/
 .venv/
+.pytest_cache/
 *.egg-info/
 build/
 dist/

CHANGELOG.md

@@ -1,5 +1,17 @@
 # Changelog
 
+## [0.2.1] - 2026-04-09
+
+### Fixed
+- **Issue #1**: Preflight-Check beim Start prüft jetzt `tesseract` und `gs` (Ghostscript). Fehlt eine Abhängigkeit, beendet sich der Service sofort mit Exit-Code 2 und klarer Fehlermeldung statt erst bei der ersten Datei.
+- **Issue #2**: `--once`-Modus liefert jetzt Exit-Code `1`, sobald **mindestens ein** PDF fehlgeschlagen ist. Exit-Code `0` nur bei vollständigem Erfolg (inkl. "keine Dateien vorhanden"). Exit-Code `2` bei Preflight-Fehler.
+
+### Added
+- Public API: `HotfolderService.run_once()`, `.success_count`, `.error_count`, `.ensure_dirs()`
+- `check_preflight()` / `PreflightError` in `pdf_ocr_hotfolder.service`
+- pytest-Test-Suite (`tests/`) mit 11 Tests — deckt alle Szenarien aus Issue #1 und #2 ab
+- `ocrmypdf`-Import in `processor.py` ist jetzt lazy (Tests ohne ocrmypdf-Installation möglich)
+
 ## [0.2.0] - 2026-04-08
 
 ### Added

VERSION

@@ -1 +1 @@
-0.2.0
+0.2.1

pdf_ocr_hotfolder/__main__.py

@@ -8,7 +8,7 @@ from pathlib import Path
 
 from . import __version__
 from .config import load_config
-from .service import HotfolderService
+from .service import HotfolderService, PreflightError
 
 
 def _setup_logging(level: str) -> None:
@@ -40,14 +40,20 @@ def main() -> int:
     _setup_logging(cfg.log_level)
 
     service = HotfolderService(cfg)
+
     if args.once:
-        service._ensure_dirs()  # noqa: SLF001
+        try:
-        service._scan_existing()  # noqa: SLF001
+            errors = service.run_once()
-        service._executor.shutdown(wait=True)  # noqa: SLF001
+        except PreflightError as e:
-        return 0
+            print(f"FEHLER: {e}", file=sys.stderr)
+            return 2
+        return 1 if errors > 0 else 0
 
     try:
         service.run()
+    except PreflightError as e:
+        print(f"FEHLER: {e}", file=sys.stderr)
+        return 2
     except KeyboardInterrupt:
         pass
     return 0

pdf_ocr_hotfolder/processor.py

@@ -7,8 +7,6 @@ import subprocess
 from dataclasses import dataclass
 from pathlib import Path
 
-import ocrmypdf
-
 from .config import OcrConfig, VeraPdfConfig
 
 log = logging.getLogger(__name__)
@@ -25,6 +23,8 @@ class ProcessResult:
 
 def run_ocr(src: Path, dst: Path, cfg: OcrConfig) -> None:
     """Führt ocrmypdf als Library-Call aus (kein Subprozess-Overhead)."""
+    import ocrmypdf  # lazy, damit Tests ohne ocrmypdf laufen
+
     kwargs: dict = {
         "language": cfg.languages,
         "jobs": cfg.jobs,

pdf_ocr_hotfolder/service.py

@@ -2,6 +2,7 @@
 from __future__ import annotations
 
 import logging
+import shutil
 import signal
 import threading
 import time
@@ -18,6 +19,27 @@ from .uploaders import notify_email, upload_folder, upload_nextcloud, upload_sft
 log = logging.getLogger(__name__)
 
 
+class PreflightError(RuntimeError):
+    """Erforderliche externe Binaries fehlen."""
+
+
+# Pflicht-Binaries für ocrmypdf
+_REQUIRED_BINARIES = ("tesseract", "gs")
+
+
+def check_preflight() -> None:
+    """Prüft, ob alle externen Abhängigkeiten (Tesseract, Ghostscript) installiert sind.
+
+    Wirft PreflightError mit Liste der fehlenden Binaries.
+    """
+    missing = [b for b in _REQUIRED_BINARIES if shutil.which(b) is None]
+    if missing:
+        raise PreflightError(
+            "Fehlende Abhängigkeiten: " + ", ".join(missing)
+            + ". Bitte installieren: sudo apt install tesseract-ocr ghostscript"
+        )
+
+
 def _is_pdf(path: Path) -> bool:
     return path.suffix.lower() == ".pdf" and path.is_file()
 
@@ -70,10 +92,20 @@ class HotfolderService:
         self._stop = threading.Event()
         self._inflight: set[str] = set()
         self._lock = threading.Lock()
+        self._success_count = 0
+        self._error_count = 0
+
+    @property
+    def success_count(self) -> int:
+        return self._success_count
+
+    @property
+    def error_count(self) -> int:
+        return self._error_count
 
     # ---- Setup ----
 
-    def _ensure_dirs(self) -> None:
+    def ensure_dirs(self) -> None:
         for p in (self.cfg.paths.incoming, self.cfg.paths.outgoing,
                   self.cfg.paths.working, self.cfg.paths.error):
             p.mkdir(parents=True, exist_ok=True)
@@ -81,7 +113,8 @@ class HotfolderService:
     # ---- Lifecycle ----
 
     def run(self) -> None:
-        self._ensure_dirs()
+        check_preflight()
+        self.ensure_dirs()
         self._scan_existing()
 
         self._observer = Observer()
@@ -98,6 +131,20 @@ class HotfolderService:
         finally:
             self.shutdown()
 
+    def run_once(self) -> int:
+        """Verarbeitet alle bereits im incoming-Ordner liegenden PDFs und beendet sich.
+
+        Returns:
+            Anzahl fehlgeschlagener PDFs (0 = alles ok).
+        """
+        check_preflight()
+        self.ensure_dirs()
+        self._scan_existing()
+        self._executor.shutdown(wait=True)
+        log.info("One-shot fertig: %d ok, %d Fehler",
+                 self._success_count, self._error_count)
+        return self._error_count
+
     def shutdown(self) -> None:
         log.info("Shutdown läuft...")
         if self._observer:
@@ -150,6 +197,12 @@ class HotfolderService:
             vera_cfg=self.cfg.verapdf,
         )
 
+        with self._lock:
+            if result.success:
+                self._success_count += 1
+            else:
+                self._error_count += 1
+
         if result.success:
             self._dispatch_uploads(result.output)
         self._notify(result)

tests/conftest.py

@@ -0,0 +1,52 @@
+"""Gemeinsame pytest-Fixtures."""
+from __future__ import annotations
+
+from pathlib import Path
+
+import pytest
+
+from pdf_ocr_hotfolder.config import (
+    Config,
+    EmailNotify,
+    FolderUpload,
+    NextcloudUpload,
+    OcrConfig,
+    Paths,
+    SftpUpload,
+    VeraPdfConfig,
+)
+
+
+@pytest.fixture
+def tmp_config(tmp_path: Path) -> Config:
+    """Minimal-Config mit tmp_path-Verzeichnissen, alle Uploads deaktiviert."""
+    paths = Paths(
+        incoming=tmp_path / "incoming",
+        outgoing=tmp_path / "outgoing",
+        working=tmp_path / "working",
+        error=tmp_path / "error",
+    )
+    for p in (paths.incoming, paths.outgoing, paths.working, paths.error):
+        p.mkdir(parents=True, exist_ok=True)
+
+    return Config(
+        paths=paths,
+        ocr=OcrConfig(max_workers=1),
+        verapdf=VeraPdfConfig(enabled=False),
+        folder=FolderUpload(enabled=False),
+        nextcloud=NextcloudUpload(enabled=False),
+        sftp=SftpUpload(enabled=False),
+        email=EmailNotify(enabled=False),
+        log_level="DEBUG",
+    )
+
+
+@pytest.fixture
+def dummy_pdf(tmp_config: Config) -> Path:
+    """Legt eine Datei mit .pdf-Extension im incoming-Ordner ab.
+
+    Achtung: kein echtes PDF. Für Tests wird `process_pdf` gemockt.
+    """
+    pdf = tmp_config.paths.incoming / "test.pdf"
+    pdf.write_bytes(b"%PDF-1.4 fake\n")
+    return pdf

tests/test_once_exit_code.py

@@ -0,0 +1,96 @@
+"""Tests für Issue #2: --once Modus muss Exit-Code != 0 bei Fehlern liefern."""
+from __future__ import annotations
+
+from pathlib import Path
+from unittest.mock import patch
+
+from pdf_ocr_hotfolder.processor import ProcessResult
+from pdf_ocr_hotfolder.service import HotfolderService
+
+
+def _fake_success(src: Path, working_dir, outgoing_dir, error_dir, ocr_cfg, vera_cfg):
+    out = outgoing_dir / f"OCR_{src.name}"
+    out.parent.mkdir(parents=True, exist_ok=True)
+    out.write_bytes(b"%PDF-1.4 ocr\n")
+    src.unlink(missing_ok=True)
+    return ProcessResult(src, out, True)
+
+
+def _fake_failure(src: Path, working_dir, outgoing_dir, error_dir, ocr_cfg, vera_cfg):
+    error_dir.mkdir(parents=True, exist_ok=True)
+    dest = error_dir / src.name
+    src.rename(dest)
+    return ProcessResult(src, outgoing_dir / f"OCR_{src.name}", False,
+                         error="fake ocr failure")
+
+
+def _run(tmp_config, fake_process):
+    """Helper: führt run_once() mit gemocktem process_pdf und preflight aus."""
+    with patch("pdf_ocr_hotfolder.service.check_preflight", return_value=None), \
+         patch("pdf_ocr_hotfolder.service.process_pdf", side_effect=fake_process), \
+         patch("pdf_ocr_hotfolder.service._wait_until_stable", return_value=True):
+        service = HotfolderService(tmp_config)
+        try:
+            return service.run_once()
+        finally:
+            service._executor.shutdown(wait=False)
+
+
+def test_once_exit_0_when_no_files(tmp_config) -> None:
+    """Szenario: Keine PDFs vorhanden → Exit 0."""
+    errors = _run(tmp_config, _fake_success)
+    assert errors == 0
+
+
+def test_once_exit_0_when_all_success(tmp_config) -> None:
+    """Szenario: Alle PDFs erfolgreich → Exit 0."""
+    (tmp_config.paths.incoming / "a.pdf").write_bytes(b"%PDF-1.4\n")
+    (tmp_config.paths.incoming / "b.pdf").write_bytes(b"%PDF-1.4\n")
+
+    errors = _run(tmp_config, _fake_success)
+    assert errors == 0
+
+
+def test_once_exit_nonzero_when_all_fail(tmp_config) -> None:
+    """Szenario: Alle PDFs fehlgeschlagen → Exit != 0 (Issue #2)."""
+    (tmp_config.paths.incoming / "a.pdf").write_bytes(b"%PDF-1.4\n")
+    (tmp_config.paths.incoming / "b.pdf").write_bytes(b"%PDF-1.4\n")
+
+    errors = _run(tmp_config, _fake_failure)
+    assert errors == 2
+
+
+def test_once_exit_nonzero_when_some_fail(tmp_config) -> None:
+    """Szenario: Teilweise fehlgeschlagen → Exit != 0."""
+    (tmp_config.paths.incoming / "ok.pdf").write_bytes(b"%PDF-1.4\n")
+    (tmp_config.paths.incoming / "bad.pdf").write_bytes(b"%PDF-1.4\n")
+
+    def mixed(src, *args, **kwargs):
+        if "bad" in src.name:
+            return _fake_failure(src, *args, **kwargs)
+        return _fake_success(src, *args, **kwargs)
+
+    errors = _run(tmp_config, mixed)
+    assert errors == 1
+
+
+def test_counters_track_success_and_failure(tmp_config) -> None:
+    """success_count und error_count sollen korrekt mitzählen."""
+    (tmp_config.paths.incoming / "ok.pdf").write_bytes(b"%PDF-1.4\n")
+    (tmp_config.paths.incoming / "bad.pdf").write_bytes(b"%PDF-1.4\n")
+
+    def mixed(src, *args, **kwargs):
+        if "bad" in src.name:
+            return _fake_failure(src, *args, **kwargs)
+        return _fake_success(src, *args, **kwargs)
+
+    with patch("pdf_ocr_hotfolder.service.check_preflight", return_value=None), \
+         patch("pdf_ocr_hotfolder.service.process_pdf", side_effect=mixed), \
+         patch("pdf_ocr_hotfolder.service._wait_until_stable", return_value=True):
+        service = HotfolderService(tmp_config)
+        try:
+            service.run_once()
+            assert service.success_count == 1
+            assert service.error_count == 1
+        finally:
+            service._executor.shutdown(wait=False)

tests/test_preflight.py

@@ -0,0 +1,75 @@
+"""Tests für Issue #1: Preflight-Check bei fehlendem Tesseract."""
+from __future__ import annotations
+
+import sys
+from unittest.mock import patch
+
+import pytest
+
+from pdf_ocr_hotfolder.service import (
+    HotfolderService,
+    PreflightError,
+    check_preflight,
+)
+
+
+def test_preflight_passes_when_all_binaries_present() -> None:
+    """Wenn tesseract + gs im PATH sind, darf kein Fehler fliegen."""
+    with patch("pdf_ocr_hotfolder.service.shutil.which", return_value="/usr/bin/fake"):
+        check_preflight()  # darf nicht werfen
+
+
+def test_preflight_fails_when_tesseract_missing() -> None:
+    """Fehlendes tesseract → PreflightError mit passender Meldung."""
+    def fake_which(name: str) -> str | None:
+        return None if name == "tesseract" else "/usr/bin/fake"
+
+    with patch("pdf_ocr_hotfolder.service.shutil.which", side_effect=fake_which):
+        with pytest.raises(PreflightError, match="tesseract"):
+            check_preflight()
+
+
+def test_preflight_fails_when_ghostscript_missing() -> None:
+    def fake_which(name: str) -> str | None:
+        return None if name == "gs" else "/usr/bin/fake"
+
+    with patch("pdf_ocr_hotfolder.service.shutil.which", side_effect=fake_which):
+        with pytest.raises(PreflightError, match="gs"):
+            check_preflight()
+
+
+def test_preflight_lists_all_missing_binaries() -> None:
+    """Bei mehreren fehlenden Binaries werden alle genannt."""
+    with patch("pdf_ocr_hotfolder.service.shutil.which", return_value=None):
+        with pytest.raises(PreflightError) as exc_info:
+            check_preflight()
+        msg = str(exc_info.value)
+        assert "tesseract" in msg
+        assert "gs" in msg
+
+
+def test_run_once_raises_preflight_error(tmp_config) -> None:
+    """HotfolderService.run_once() wirft PreflightError, wenn tesseract fehlt."""
+    service = HotfolderService(tmp_config)
+    try:
+        with patch("pdf_ocr_hotfolder.service.shutil.which", return_value=None):
+            with pytest.raises(PreflightError):
+                service.run_once()
+    finally:
+        service._executor.shutdown(wait=False)
+
+
+def test_main_returns_2_on_preflight_error(tmp_config, tmp_path, monkeypatch) -> None:
+    """CLI liefert Exit-Code 2 bei Preflight-Fehler (Issue #1 Szenario)."""
+    cfg_file = tmp_path / "cfg.toml"
+    cfg_file.write_text(f"""
+[paths]
+incoming = "{tmp_config.paths.incoming}"
+outgoing = "{tmp_config.paths.outgoing}"
+working  = "{tmp_config.paths.working}"
+error    = "{tmp_config.paths.error}"
+""")
+    monkeypatch.setattr(sys, "argv", ["pdf-ocr-hotfolder", "--config", str(cfg_file), "--once"])
+    with patch("pdf_ocr_hotfolder.service.shutil.which", return_value=None):
+        from pdf_ocr_hotfolder.__main__ import main
+        assert main() == 2