asn: fix check for path type, check: add more checks

is_file is a method, not a member, therefore is_file always evaluates to true

Author: sebix

intelmq/bots/experts/asn_lookup/expert.py

@@ -36,12 +36,10 @@ def init(self):
         try:
             self._database = pyasn.pyasn(self.database)
         except OSError:
-            self.logger.error("pyasn data file does not exist or could not be "
-                              "accessed in %r.", self.database)
-            self.logger.error("Read 'bots/experts/asn_lookup/README' and "
-                              "follow the procedure.")
+            raise ValueError(f"pyasn data file does not exist or could not be accessed in {self.database!r}. ",
+                             "Please see https://docs.intelmq.org/latest/user/bots/#asn-lookup")
             self.stop()
-        if not Path(self.database).is_file:
+        if not Path(self.database).is_file():
             raise ValueError('Database file does not exist or is not a file.')
 
     def process(self):
@@ -69,12 +67,15 @@ def process(self):
 
     @staticmethod
     def check(parameters):
-        if not os.path.exists(parameters.get('database', '')):
-            return [["error", "File given as parameter 'database' does not exist."]]
+        database_path = Path(parameters.get('database', ''))
+        if not database_path.exists():
+            return [["error", f"File given as parameter 'database' ({database_path!s}) does not exist."]]
+        elif not database_path.is_file():
+            return [["error", f"Parameter 'database' ({database_path!s}) exists, but is not a file."]]
         try:
             pyasn.pyasn(parameters['database'])
         except Exception as exc:
-            return [["error", "Error reading database: %r." % exc]]
+            return [["error", f"Error reading database ({database_path!s}): %r." % exc]]
 
     @classmethod
     def run(cls, parsed_args=None):
@@ -116,7 +117,7 @@ def update_database(cls, verbose=False):
             raise MissingDependencyError("pyasn")
 
         for database_path in set(bots.values()):
-            if not Path(database_path).is_file:
+            if not Path(database_path).is_file():
                 raise ValueError('Database file does not exist or is not a file.')
             elif not os.access(database_path, os.W_OK):
                 raise ValueError('Database file is not writeable.')