Chore: Update Singleton Pattern

Chore: Update Container

Dockerfile

@@ -0,0 +1,20 @@
+FROM python:3.8-slim-buster
+EXPOSE 8080
+
+ENV PYTHONUNBUFFERED 1
+ENV APP_HOME /app
+
+COPY requirements.txt .
+
+RUN pip install --no-cache-dir -U pip \
+    && pip install --no-cache-dir -r requirements.txt
+
+WORKDIR ${APP_HOME}
+
+COPY src src
+COPY main.py .
+COPY docker-entrypoint.sh .
+COPY .env .
+
+ENTRYPOINT ["/bin/bash"]
+CMD ["./docker-entrypoint.sh"]

docker-compose.yml

@@ -0,0 +1,32 @@
+version: "3.5"
+services:
+  user_app:
+    build: .
+    container_name: cdslab_models_app
+    env_file: .env
+    image: cdslab_user
+    networks:
+      - cdslab_models
+    ports:
+      - 5000:5000
+    volumes:
+    - ./src:/app/src
+
+  user_mongo:
+    container_name: cdslab_models_mongo
+    environment:
+      MONGO_INITDB_ROOT_USERNAME: cdsuser
+      MONGO_INITDB_ROOT_PASSWORD: cdspass
+    image: mongo:3-xenial
+    networks:
+      - cdslab_models
+    ports:
+      - 27017:27017
+    volumes:
+      - /tmp/data/cdslab_models/:/data/db
+
+
+networks:
+  cdslab_models:
+    name: cdslab_user
+    driver: bridge

docker-entrypoint.sh

@@ -0,0 +1,7 @@
+#!/bin/bash
+
+if [ -z "${PORT}" ] ; then PORT=8080; fi
+
+if [ -z "${HOST}" ] ; then HOST=0.0.0.0; fi
+
+uvicorn main:app --port=${PORT} --host=${HOST} --reload

main.py

@@ -1,8 +1,10 @@
 import uvicorn
 
+from src.api import app
 from src.config import settings
 from src.use_cases.cmodels import CmodelUseCases
 
+__all__ = ['app']
 
 if __name__ == '__main__':
     CmodelUseCases.update_cmodels_collection()

requirements.txt

@@ -14,6 +14,7 @@ iniconfig==1.1.1
 mccabe==0.6.1
 mongomock==3.22.1
 packaging==20.9; python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'
+pandas==1.2.4
 pluggy==0.13.1; python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'
 py==1.10.0; python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'
 pycodestyle==2.7.0; python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'
@@ -24,6 +25,7 @@ pyparsing==2.4.7; python_version >= '2.6' and python_version not in '3.0, 3.1, 3
 pytest-cov==2.11.1
 pytest==6.2.3
 python-dotenv==0.17.0
+python-multipart==0.0.5
 requests==2.25.1
 sentinels==1.0.0
 six==1.15.0; python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'

src/api.py

@@ -5,21 +5,19 @@
 from src.config import settings
 from src.routers.main import main_router
 
-
 app = FastAPI()
 
-
 app.add_middleware(
     TrustedHostMiddleware,
-    allowed_hosts=settings["ALLOWED_HOSTS"].split(",")
+    allowed_hosts=settings.get("ALLOWED_HOSTS", "*").split(",")
 )
 
 app.add_middleware(
     CORSMiddleware,
     allow_credentials=True,
-    allow_origins=settings["ALLOWED_ORIGINS"].split(","),
-    allow_methods=settings["ALLOWED_METHODS"].split(","),
-    allow_headers=settings["ALLOWED_HEADERS"].split(",")
+    allow_origins=settings.get("ALLOWED_ORIGINS", "*").split(","),
+    allow_methods=settings.get("ALLOWED_METHODS", "*").split(","),
+    allow_headers=settings.get("ALLOWED_HEADERS", "*").split(",")
 )
 
 app.include_router(

src/db/mongo.py

@@ -1,63 +1,59 @@
 from typing import Generator, Tuple
 
 from pymongo import MongoClient
-from pymongo.database import Database
 from pymongo.collection import Collection
+from pymongo.database import Database
 
 from src.config import db_config
-
-
-def api_get_db_connection(
-    db_uri: str = db_config['MONGO_URI'],
-) -> Generator[MongoClient, None, None]:
-    """Creates connection to Mongodb server.
-
-    Yields
-    ------
-    db_connection: MongoClient
-        Object containing the db connection.
-    """
-    db_connection = MongoClient(db_uri)
-
-    try:
-        yield db_connection
-    finally:
-        db_connection.close()
-
-
-def get_db(
-    db_uri: str = db_config['MONGO_URI'],
-    db_name: str = db_config['MONGO_DB']
-) -> Tuple[MongoClient, Database]:
-    """Gets Mongodb connection and database.
-
-    Parameters
-    ----------
-    db_uri: str
-        Mongo server URI.
-    db_name: str
-        Mongo database name.
-
-    Returns
-    -------
-    db_connection : MongoClient
-    db : pymongo.database.Database
-    """
-    db_connection = MongoClient(db_uri)
-    db: Database = db_connection[db_name]
-
-    return db_connection, db
-
-
-def get_collection(
-    coll_name: str = db_config['CMODELS_COLL']
-) -> Tuple[MongoClient, Collection]:
-    """
-    Returns
-    -------
-    db_connection: pymongo.MongoClient
-    coll: pymongo.collection.Collection
-    """
-    db_connection, db = get_db()
-    coll: Collection = db[coll_name]
-    return db_connection, coll
+from src.utils.patterns import Singleton
+
+
+class MongoConnection(metaclass=Singleton):
+    db_uri = db_config.get('MONGO_URI')
+    db_name = db_config.get('MONGO_DB')
+    collection_name = db_config.get('CMODELS_COLL')
+
+    def api_get_db_connection(self) -> Generator[MongoClient, None, None]:
+        """Creates connection to Mongodb server.
+
+        Yields
+        ------
+        db_connection: MongoClient
+            Object containing the db connection.
+        """
+        db_connection = MongoClient(self.db_uri)
+
+        try:
+            yield db_connection
+        finally:
+            db_connection.close()
+
+    def get_db(self) -> Tuple[MongoClient, Database]:
+        """Gets Mongodb connection and database.
+
+        Returns
+        -------
+        db_connection : MongoClient
+        db : pymongo.database.Database
+        """
+        db_connection = MongoClient(self.db_uri)
+        db: Database = db_connection[self.db_name]
+
+        return db_connection, db
+
+    def get_collection(
+            self,
+            collection_name: str = None
+    ) -> Tuple[MongoClient, Collection]:
+        """
+        Returns
+        -------
+        db_connection: pymongo.MongoClient
+        coll: pymongo.collection.Collection
+        """
+        if not collection_name:
+            collection_name = self.collection_name
+            pass
+        db_connection, db = self.get_db()
+        coll: Collection = db[collection_name]
+        return db_connection, coll

src/interfaces/crud.py

@@ -4,7 +4,7 @@
 from pymongo.mongo_client import MongoClient
 
 
-class MongoCRUD():
+class MongoCRUD:
     def __init__(
         self,
         db_connection: MongoClient,

src/routers/main.py

@@ -3,6 +3,7 @@
 main_router_prefix = ""
 main_router = APIRouter(prefix=main_router_prefix)
 
+
 @main_router.get('/')
 async def hello(request: Request):
     return {'hello': 'world'}

src/use_cases/cmodels.py

@@ -1,10 +1,10 @@
-from src.db.mongo import get_collection
+from src.db.mongo import MongoConnection
 from src.interfaces.cmodels import CModelsInterface
 
 
 class CmodelUseCases:
     @staticmethod
     def update_cmodels_collection():
-        db_connection, cmodels_coll = get_collection()
+        db_connection, cmodels_coll = MongoConnection().get_collection()
         cmodels_interface = CModelsInterface(db_connection, cmodels_coll)
         cmodels_interface.insert_all_cmodel_documents()

src/utils/patterns.py

@@ -0,0 +1,7 @@
+class Singleton(type):
+    _instances = {}
+
+    def __call__(cls, *args, **kwargs):
+        if cls not in cls._instances:
+            cls._instances[cls] = super(Singleton, cls).__call__(*args, **kwargs)
+        return cls._instances[cls]