diff --git a/hydrus/app.py b/hydrus/app.py
index 92e328f3..dc64b2de 100644
--- a/hydrus/app.py
+++ b/hydrus/app.py
@@ -1,28 +1,36 @@
 """Main route for the application"""
 
 import logging
+import sys
+from hydrus.socketio_factory import create_socket
+from os.path import dirname, abspath
 
-from sqlalchemy import create_engine
+# insert the ./app.py file path in the PYTHONPATH variable for imports to work
+sys.path.insert(0, dirname(dirname(abspath(__file__))))
 
-from gevent.pywsgi import WSGIServer
-from sqlalchemy.orm import sessionmaker
+# ignoring import error by flake 8 temporarily
+# for setting PYTHONPATH before imports
+from sqlalchemy import create_engine  # noqa: E402
+from flask import request  # noqa: E402
+from collections import defaultdict  # noqa: E402
+from gevent.pywsgi import WSGIServer  # noqa: E402
+from sqlalchemy.orm import sessionmaker  # noqa: E402
 
-from hydrus.app_factory import app_factory
+from hydrus.app_factory import app_factory  # noqa: E402
 from hydrus.conf import (
-    HYDRUS_SERVER_URL, API_NAME, DB_URL, APIDOC_OBJ, PORT, DEBUG)
-from hydrus.data import doc_parse
-from hydrus.data.db_models import Base, create_database_tables
-from hydrus.data.exceptions import UserExists
-from hydrus.data.user import add_user
-from hydra_python_core import doc_maker
+    HYDRUS_SERVER_URL, API_NAME,
+    DB_URL, APIDOC_OBJ, PORT)  # noqa: E402
+from hydrus.data import doc_parse  # noqa: E402
+from hydrus.data.db_models import Base  # noqa: E402
+from hydrus.data.exceptions import UserExists  # noqa: E402
+from hydrus.data.user import add_user  # noqa: E402
+from hydra_python_core import doc_maker  # noqa: E402
 from hydrus.utils import (
     set_session, set_doc, set_hydrus_server_url,
-    set_token, set_api_name, set_authentication)
-from hydrus.socketio_factory import create_socket
+    set_token, set_api_name, set_authentication)  # noqa: E402
 
 logger = logging.getLogger(__file__)
 
-# TODO: loading the engine and creating the tables should be handled better
 engine = create_engine(DB_URL)
 session = sessionmaker(bind=engine)()
 
@@ -33,7 +41,6 @@
 classes = doc_parse.get_classes(apidoc)
 try:
     Base.metadata.drop_all(engine)
-    create_database_tables(classes)
     Base.metadata.create_all(engine)
 except Exception:
     pass
@@ -50,6 +57,43 @@
 # Create a Hydrus app
 app = app_factory(API_NAME)
 socketio = create_socket(app, session)
+
+# global dict to store mapping of each function to be run before
+# specified route.
+# stores in the form {'path1': {'method1': function_before_path1_for_method1}}
+before_request_funcs = defaultdict(dict)
+
+
+@app.before_request
+def before_request_callback():
+    path = request.path
+    method = request.method
+    global before_request_funcs
+    func = before_request_funcs.get(path, {}).get(method, None)
+    if func:
+        func()
+
+
+# decorator to define logic for custom before request methods
+def custom_before_request(path, method):
+    def wrapper(f):
+        global before_request_funcs
+        before_request_funcs[path][method] = f
+        return f
+
+    return wrapper
+
+
+@custom_before_request('/api/MessageCollection', 'PUT')
+def do_this_before_put_on_drone_collections():
+    print("Do something before PUT request on MessageCollection")
+
+
+@custom_before_request('/api/MessageCollection', 'GET')
+def do_this_before_get_on_drone_collections():
+    print("Do something before GET request on MessageCollection")
+
+
 #
 # Nested context managers
 #
@@ -58,17 +102,17 @@
 # Set HYDRUS_SERVER_URL
 # Set the Database session
 with set_authentication(app, AUTH), set_token(app, TOKEN), \
-     set_api_name(app, API_NAME), set_doc(app, apidoc), \
-     set_hydrus_server_url(app, HYDRUS_SERVER_URL), set_session(app, session):
-        if __name__ == "__main__":
-            # this is run only if development server is run
-            # Set the name of the API
-            socketio.run(app=app, debug=True, port=PORT)
-        else:
-            # Start the Hydrus app
-            http_server = WSGIServer(('', PORT), app)
-            logger.info(f'Running server at port {PORT}')
-            try:
-                http_server.serve_forever()
-            except KeyboardInterrupt:
-                pass
+        set_api_name(app, API_NAME), set_doc(app, apidoc), \
+        set_hydrus_server_url(app, HYDRUS_SERVER_URL), set_session(app, session):
+    if __name__ == "__main__":
+        # this is run only if development server is run
+        # Set the name of the API
+        socketio.run(app=app, debug=True, port=PORT)
+    else:
+        # Start the Hydrus app
+        http_server = WSGIServer(('', PORT), app)
+        logger.info(f'Running server at port {PORT}')
+        try:
+            http_server.serve_forever()
+        except KeyboardInterrupt:
+            pass