make parse_record abstract

Signed-off-by: Szymon Łopaciuk <[email protected]>

hepcrawl/spiders/oaipmh_spider.py

@@ -9,6 +9,7 @@
 
 """Generic spider for OAI-PMH servers."""
 
+import abc
 import logging
 from errno import EEXIST as FILE_EXISTS, ENOENT as NO_SUCH_FILE_OR_DIR
 from datetime import datetime
@@ -42,6 +43,7 @@ class OAIPMHSpider(StatefulSpider):
     the initial starting date and will use it as `from_date` argument on the
     next harvest.
     """
+    __metaclass__ = abc.ABCMeta
     name = 'OAI-PMH'
 
     def __init__(
@@ -84,6 +86,7 @@ def start_requests(self):
         LOGGER.info("Harvesting completed. Next harvesting will resume from {}"
                     .format(self.until_date or now.strftime('%Y-%m-%d')))
 
+    @abc.abstractmethod
     def parse_record(self, record):
         """
         This method need to be reimplemented in order to provide special parsing.

tests/unit/test_oaipmh.py

@@ -43,7 +43,11 @@ def settings():
 
 @pytest.fixture
 def spider(settings):
-    spider = OAIPMHSpider('http://0.0.0.0/oai2', settings=settings)
+    class TestOAIPMHSpider(OAIPMHSpider):
+        def parse_record(self, record):
+            return None
+
+    spider = TestOAIPMHSpider('http://0.0.0.0/oai2', settings=settings)
     spider.from_date = '2017-12-08'
     spider.set = 'physics:hep-th'
     spider.metadata_prefix = 'marcxml'