metadata writer: test setup

src/photools3/metadata_writer.py

@@ -70,32 +70,39 @@ class MetadataWriter:
     def sidecar_path(self) -> Path:
         return Path()
 
-    @property
+    def get_metadata(self, *args, **kwargs) -> Any:
-    def metadata(self) -> XmpMetadata:
         try:
             with exiftool.ExifToolHelper() as exif:
                 metadata = exif.get_metadata([str(self.path)])[0]
         except Exception as exc:  # noqa: BLE001
             log.error(f"Could not read metadata from {self.path}: {exc}")
         assert metadata
-        return metadata
+        return metadata.get(*args, **kwargs)
 
-    def set_metadata(self):
+    def set_metadata(self, metadata_tags: dict[str, Any]) -> bool:
         if self.sidecar_path.exists():
             params = ["-overwrite_original"]
         else:
             params = ["-o", "%f.xmp"]
-        # TODO
+        try:
+            with exiftool.ExifToolHelper() as exif:
+                exif.set_tags(
+                    [str(self.sidecar_path)], tags=metadata_tags, params=params
+                )
+        except Exception as exc:  # noqa
+            log.error(f"Could not write metadata to file {self.sidecar_path}: {exc}")
+            return False
+        return True
 
     def write_caption(self, caption: Caption):
-        existing = self.metadata.get(XMP_KEYS_CAPTION[0], "")
+        existing = self.get_metadata(XMP_KEYS_CAPTION[0], "")
         is_existing_prefixed = _is_prefixed(existing)
         if existing and is_existing_prefixed:
             return
         elif existing and not is_existing_prefixed:
             caption = f"{existing}. {_prefixed(caption)}"
         metadata_tags = {key: caption for key in XMP_KEYS_CAPTION}
-        # TODO
+        self.set_metadata(metadata_tags)
 
     def write_keywords(self, keywords: Keywords): ...
 

test/test_metadata_writer.py

@@ -1,7 +1,31 @@
-from photools3.metadata_writer import read_metadata
+from pathlib import Path
+
+import pytest
+
+from photools3.metadata_writer import MetadataWriter
 from test.test_photo import PATHS_DNG_EXAMPLES
 
 
-def test_read_metadata():
+@pytest.fixture
-    result = read_metadata(PATHS_DNG_EXAMPLES[0])
+def make_dng_file(tmp_path):
+    def _make(index: int = 0) -> Path:
+        src = PATHS_DNG_EXAMPLES[index]
+        dst = tmp_path / f"copy_{index}_{src.name}"
+        return dst
+    return _make
+
+@pytest.fixture
+def dng_file(make_dng):
+    return make_dng()
+
+def test_read_metadata(make_dng_file):
+    """primitive test for `MetadataWriter`"""
+    file_path = make_dng_file()
+    result = MetadataWriter(file_path)
     assert result
+
+@pytest.mark.parametrize("idx", range(len(PATHS_DNG_EXAMPLES)))
+def test_read_metadata_sidecar_path(make_dng_file, idx):
+    file_path = make_dng_file(idx)
+    metadata_writer = MetadataWriter(file_path)
+    assert isinstance(metadata_writer.sidecar_path, Path)