1 files changed, 22 insertions, 18 deletions
diff --git a/bsie/extractor/generic/path.py b/bsie/extractor/generic/path.py
index c39bbd2..f358a79 100644
--- a/bsie/extractor/generic/path.py
+++ b/bsie/extractor/generic/path.py
@@ -8,11 +8,10 @@ Author: Matthias Baumgartner, 2022
 import os
 import typing
 
-# inner-module imports
+# bsie imports
 from bsie.base import extractor
 from bsie.utils import node, ns
-from bsie.utils.bsfs import URI
-import bsie.reader.path
+from bsie.utils.bsfs import schema
 
 # exports
 __all__: typing.Sequence[str] = (
@@ -27,30 +26,31 @@ class Path(extractor.Extractor):
 
     CONTENT_READER = bsie.reader.path.Path
 
-    def __init__(self):
-        self.__callmap = {
-            ns.bse.filename:    self.__filename,
-            }
+    # mapping from predicate to handler function.
+    _callmap: typing.Dict[schema.Predicate, typing.Callable[[str], typing.Any]]
 
-    def schema(self) -> str:
-        return '''
-            bse:filename a bsfs:Predicate ;
+    def __init__(self):
+        super().__init__(schema.Schema.from_string(extractor.SCHEMA_PREAMBLE + '''
+            bse:filename rdfs:subClassOf bsfs:Predicate ;
                 rdfs:domain bsfs:Entity ;
                 rdfs:range xsd:string ;
-                rdf:label "File name"^^xsd:string ;
+                rdfs:label "File name"^^xsd:string ;
                 schema:description "Filename of entity in some filesystem."^^xsd:string ;
                 owl:maxCardinality "INF"^^xsd:number .
-            '''
+            '''))
+        self._callmap = {
+            self.schema.predicate(ns.bse.filename): self.__filename,
+            }
 
     def extract(
             self,
             subject: node.Node,
             content: CONTENT_READER.CONTENT_TYPE,
-            predicates: typing.Iterable[URI],
-            ) -> typing.Iterator[typing.Tuple[node.Node, URI, typing.Any]]:
+            predicates: typing.Iterable[schema.Predicate],
+            ) -> typing.Iterator[typing.Tuple[node.Node, schema.Predicate, typing.Any]]:
         for pred in predicates:
             # find callback
-            clbk = self.__callmap.get(pred)
+            clbk = self._callmap.get(pred)
             if clbk is None:
                 continue
             # get value
@@ -60,11 +60,15 @@ class Path(extractor.Extractor):
             # produce triple
             yield subject, pred, value
 
-    def __filename(self, path: str) -> str:
+    def __filename(self, path: str) -> typing.Optional[str]:
         try:
             return os.path.basename(path)
-        except Exception:
-            # FIXME: some kind of error reporting (e.g. logging)
+        except Exception: # some error, skip.
+            # FIXME: some kind of error reporting (e.g. logging)?
+            # Options: (a) Fail silently (current); (b) Skip and report to log;
+            # (c) Raise ExtractorError (aborts extraction); (d) separate content type
+            # checks from basename errors (report content type errors, skip basename
+            # errors)
             return None
 
 ## EOF ##