FEAT: Add prototype of dynamic routes in hydrus

hydrus/app.py

@@ -1,23 +1,30 @@
 """Main route for the application"""
 
 import logging
+import sys
+from os.path import dirname, abspath
+# insert the ./app.py file path in the PYTHONPATH variable for imports to work
+sys.path.insert(0, dirname(dirname(abspath(__file__))))
 
-from sqlalchemy import create_engine
+# 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 gevent.pywsgi import WSGIServer
-from sqlalchemy.orm import sessionmaker
-
-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
-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, DEBUG)  # 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)
+    set_token, set_api_name, set_authentication)  # noqa: E402
 
 logger = logging.getLogger(__file__)
 
@@ -42,8 +49,8 @@
 doc_parse.insert_classes(classes, session)
 doc_parse.insert_properties(properties, session)
 
-AUTH = True
-TOKEN = True
+AUTH = False
+TOKEN = False
 
 if AUTH:
     try:
@@ -54,6 +61,41 @@
 # Create a Hydrus app
 app = app_factory(API_NAME)
 
+# 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")
+
+
 with set_authentication(app, AUTH):
     # Use authentication for all requests
     with set_token(app, TOKEN):