Refactor of caching & data storage part 3 #118

sigrefdataproviders/local_file_sig_ref_data_provider.py

@@ -0,0 +1,36 @@
+import logging
+from datetime import datetime
+
+import pytz
+
+from sigrefdataproviders.sig_ref_data_provider import SIGRefDataProvider
+
+
+class LocalFileSIGRefDataProvider(SIGRefDataProvider):
+    """Generic SIG ref data provider class for providers that fetch their data from a local file on startup."""
+
+    def __init__(self, sig, provider_config, path):
+        super().__init__(sig, provider_config)
+        self._path = path
+
+    def start(self):
+        logging.info("Loading " + self.sig_name + " SIG ref data from file.")
+        try:
+            new_data = self._file_to_data(self._path)
+            if new_data:
+                self._replace_data(new_data)
+                self.status = "OK"
+                self.last_update_time = datetime.now(pytz.UTC)
+            else:
+                logging.info("No new SIG ref data found for " + self.sig_name)
+        except Exception as e:
+            self.status = "Error"
+            logging.exception("Exception in local file SIG Ref Data Provider (" + self.sig_name + ")")
+
+    def stop(self):
+        pass
+
+    def _file_to_data(self, path):
+        """Load a file on the given path and turn it into SIG Ref data."""
+
+        raise NotImplementedError("Subclasses must implement this method")