Truncate long identifier values in file paths

ingestify/domain/services/identifier_key_transformer.py

@@ -143,8 +143,13 @@ def to_path(self, provider: str, dataset_type: str, identifier: dict) -> str:
                 path_parts.append(f"{key}_{suffix}={transformed_value}")
 
             # Append the original value (either standalone for identity or alongside transformed).
-            # URL-encode the value so special characters, spaces, etc. are safe in paths.
-            path_parts.append(f"{key}={quote(str(value), safe='')}")
+            # Truncate long values before encoding to keep paths under
+            # filesystem/GCS limits. Append a short hash to preserve uniqueness.
+            str_value = str(value)
+            if len(str_value) > 40:
+                short_hash = hashlib.md5(str_value.encode()).hexdigest()[:8]
+                str_value = f"{str_value[:40]}_{short_hash}"
+            path_parts.append(f"{key}={quote(str_value, safe='')}")
 
         # Join the parts with `/` to form the full path
         return "/".join(path_parts)

ingestify/tests/test_identifier_transformer.py

@@ -0,0 +1,37 @@
+"""Tests for IdentifierTransformer.to_path."""
+from ingestify.domain.services.identifier_key_transformer import IdentifierTransformer
+
+
+def test_to_path_short_value_unchanged():
+    t = IdentifierTransformer()
+    path = t.to_path("p", "d", {"key": "short"})
+    assert path == "key=short"
+
+
+def test_to_path_special_chars_url_encoded():
+    t = IdentifierTransformer()
+    path = t.to_path("p", "d", {"key": "$99 mattress"})
+    assert path == "key=%2499%20mattress"
+
+
+def test_to_path_long_value_truncated_with_hash():
+    t = IdentifierTransformer()
+    long_value = "a" * 50
+    path = t.to_path("p", "d", {"key": long_value})
+    # Truncated at 40 chars + _ + 8-char hash
+    assert path.startswith("key=" + "a" * 40 + "_")
+    assert len(path.split("=")[1]) == 40 + 1 + 8  # value_hash
+
+
+def test_to_path_long_value_hash_is_stable():
+    t = IdentifierTransformer()
+    long_value = "keyword " * 10
+    path1 = t.to_path("p", "d", {"key": long_value})
+    path2 = t.to_path("p", "d", {"key": long_value})
+    assert path1 == path2
+
+
+def test_to_path_integer_value_unchanged():
+    t = IdentifierTransformer()
+    path = t.to_path("p", "d", {"id": 12345})
+    assert path == "id=12345"