Optional: filter airports by country

ogn/commands/showairport.py

@@ -2,14 +2,23 @@ from ogn.model import Airport
 from ogn.commands.dbutils import session
 
 from manager import Manager
+from sqlalchemy import and_, between
 manager = Manager()
 
 
+@manager.arg('country_code', help='filter by country code, eg. "de" for germany')
 @manager.command
-def list_all():
+def list_all(country_code=None):
     """Show a list of all airports."""
+    or_args = []
+    if country_code is None:
+        or_args = [between(Airport.style, 2, 5)]
+    else:
+        or_args = [and_(between(Airport.style, 2, 5),
+                        Airport.country_code == country_code)]
     query = session.query(Airport) \
-        .order_by(Airport.name)
+        .order_by(Airport.name) \
+        .filter(*or_args)
 
     print('--- Airports ---')
     for airport in query.all():