Merge pull request #1 from alexdiamandi/creationalPatternBranch

Creational pattern branch

Author: alexdiamandi

app/caches.py

@@ -5,11 +5,11 @@
 
 import aiocache
 
-from .config import get_settings
+from .config import _Settings
 
 LOGGER = logging.getLogger(name="app.caches")
 
-SETTINGS = get_settings()
+SETTINGS = _Settings.get_settings()
 
 if SETTINGS.rediscloud_url:
     REDIS_URL = SETTINGS.rediscloud_url

app/config.py

@@ -8,6 +8,9 @@
 
 
 class _Settings(BaseSettings):
+
+    settingsInstance = None
+
     port: int = 5000
     rediscloud_url: AnyUrl = None
     local_redis_url: AnyUrl = None
@@ -16,18 +19,23 @@ class _Settings(BaseSettings):
     # Sentry
     sentry_dsn: str = None
 
+    def __init__(self):
+        if _Settings.settingsInstance:
+            raise Exception("This is a singleton")
+        else:
+            _Settings.settingsInstance = self
 
 @functools.lru_cache()
-def get_settings(**kwargs) -> BaseSettings:
-    """
-    Read settings from the environment or `.env` file.
-    https://pydantic-docs.helpmanual.io/usage/settings/#dotenv-env-support
-
-    Usage:
-        import app.config
-
-        settings = app.config.get_settings(_env_file="")
-        port_number = settings.port
-    """
-    CFG_LOGGER.info("Loading Config settings from Environment ...")
-    return _Settings(**kwargs)
+    def get_settings(**kwargs) -> BaseSettings:
+        """
+        Read settings from the environment or `.env` file.
+        https://pydantic-docs.helpmanual.io/usage/settings/#dotenv-env-support
+
+        Usage:
+            import app.config
+
+            settings = app.config._Settings.get_settings(_env_file="")
+            port_number = settings.port
+        """
+        CFG_LOGGER.info("Loading Config settings from Environment ...")
+        return _Settings(**kwargs)

app/main.py

@@ -13,7 +13,7 @@
 from scout_apm.async_.starlette import ScoutMiddleware
 from sentry_sdk.integrations.asgi import SentryAsgiMiddleware
 
-from .config import get_settings
+from .config import _Settings
 from .data import data_source
 from .routers import V1, V2
 from .utils.httputils import setup_client_session, teardown_client_session
@@ -23,7 +23,7 @@
 # ############
 LOGGER = logging.getLogger("api")
 
-SETTINGS = get_settings()
+SETTINGS = _Settings.get_settings()
 
 if SETTINGS.sentry_dsn:  # pragma: no cover
     sentry_sdk.init(dsn=SETTINGS.sentry_dsn)
@@ -113,7 +113,6 @@ async def handle_validation_error(
 APP.include_router(V1, prefix="", tags=["v1"])
 APP.include_router(V2, prefix="/v2", tags=["v2"])
 
-
 # Running of app.
 if __name__ == "__main__":
     uvicorn.run(