🏗️ update app implement application factory pattern

Author: Alvaro Farias

app/__init__.py

@@ -4,16 +4,39 @@
 from config.application import config
 from app.http.controllers.api.PredictionController import PredictionController
 
-app = Flask(__name__)
-app.config.from_mapping(
-    ENV=config['env'],
-    DEBUG=config['debug'],
-    SECRET_KEY=config['key']
-)
+# -------------------------------------------------------------------------
+# Extension Objects
+# -------------------------------------------------------------------------
+#
+# Initialize extensions accessible to any part of our app
+api = Api()
 
-CORS(app, origins=config['origins'])
 
-api = Api(app)
-api.add_resource(PredictionController, '/prediction')
+def create_app() -> Flask:
+    """
+    Create The Application
+    The first thing we will do is create a new application instance
+    which serves as the "glue" for all the components of the api.
+    :return: Flask
+    """
+    app = Flask(__name__)
 
-__version__ = "0.1"
+    app.config.from_mapping(
+        ENV=config['env'],
+        DEBUG=config['debug'],
+        SECRET_KEY=config['key']
+    )
+
+    CORS(app, origins=config['origins'])
+
+    # Initialize Extensions
+    api.init_app(app)
+
+    with app.app_context():
+        # Register resources
+        api.add_resource(PredictionController, '/prediction')
+
+    return app
+
+
+__version__ = "0.1.0"