ENH: `date_parse` transformer function

src/caoscrawler/converters.py

@@ -1246,6 +1246,7 @@ class DateElementConverter(TextElementConverter):
 
     """
 
+    # TODO make `date` parameter name configurable
     def match(self, element: StructureElement):
         matches = super().match(element)
         if matches is not None and "date" in matches:
@@ -1266,7 +1267,7 @@ https://docs.python.org/3/library/datetime.html#strftime-and-strptime-format-cod
 
     """
 
-    # TODO make `val` configurable
+    # TODO make `val` parameter name configurable
     def match(self, element: StructureElement):
         matches = super().match(element)
         if matches is not None and "val" in matches:

src/caoscrawler/default_transformers.yml

@@ -9,6 +9,9 @@ split:
 replace:
   package: caoscrawler.transformer_functions
   function: replace
+date_parse:
+  package: caoscrawler.transformer_functions
+  function: date_parse
 datetime_parse:
   package: caoscrawler.transformer_functions
   function: datetime_parse

src/caoscrawler/transformer_functions.py

@@ -68,6 +68,22 @@ def replace(in_value: Any, in_parameters: dict):
     return in_value.replace(in_parameters['remove'], in_parameters['insert'])
 
 
+def date_parse(in_value: str, params: dict):
+    """Transform text so that it is formatted in a way that LinkAhead can understand it.
+
+Parameters
+==========
+
+- date_format: str, optional
+    A format string using the ``datetime`` specificaton:
+    https://docs.python.org/3/library/datetime.html#strftime-and-strptime-format-codes
+    """
+    fmt_default = "%Y-%m-%d"
+    fmt = params.get("date_format", fmt_default)
+    dt_str = datetime.datetime.strptime(in_value, fmt).strftime(fmt_default)
+    return dt_str
+
+
 def datetime_parse(in_value: str, params: dict):
     """Transform text so that it is formatted in a way that LinkAhead can understand it.