clean up constructor

klondike/snowflake/snowflake.py

@@ -34,22 +34,64 @@ class SnowflakeConnector:
 
     def __init__(
         self,
-        snowflake_user: str = os.getenv("SNOWFLAKE_USER"),
-        snowflake_password: str = os.getenv("SNOWFLAKE_PASSWORD"),
-        snowflake_account: str = os.getenv("SNOWFLAKE_ACCOUNT"),
-        snowflake_database: str = os.getenv("SNOWFLAKE_DATABASE"),
-        snowflake_warehouse: str = os.getenv("SNOWFLAKE_WAREHOUSE"),
+        snowflake_user: Optional[str] = None,
+        snowflake_password: Optional[str] = None,
+        snowflake_account: Optional[str] = None,
+        snowflake_database: Optional[str] = None,
+        snowflake_warehouse: Optional[str] = None,
         row_chunk_size: int = 100_000,
     ):
-        self.snowflake_user = snowflake_user
-        self.snowflake_password = snowflake_password
-        self.snowflake_account = snowflake_account
-        self.__snowflake_warehouse = snowflake_warehouse
-        self.__snowflake_database = snowflake_database
+        """
+        All Snowflake connection values either need to be supplied as constructor
+        arguments or inferred from the environment; if neither occurs, a `ValueError`
+        will be raised
+        """
+
+        self.snowflake_user = (
+            snowflake_user if snowflake_user else os.getenv("SNOWFLAKE_USER")
+        )
+        self.snowflake_password = (
+            snowflake_password
+            if snowflake_password
+            else os.getenv("SNOWFLAKE_PASSWORD")
+        )
+        self.snowflake_account = (
+            snowflake_account if snowflake_account else os.getenv("SNOWFLAKE_ACCOUNT")
+        )
+        self.__snowflake_warehouse = (
+            snowflake_warehouse
+            if snowflake_warehouse
+            else os.getenv("SNOWFLAKE_WAREHOUSE")
+        )
+        self.__snowflake_database = (
+            snowflake_database
+            if snowflake_database
+            else os.getenv("SNOWFLAKE_DATABASE")
+        )
+
+        ###
+
+        self.__validate_authentication()
+
+        ###
 
         self.dialect = "snowflake"
         self.__row_chunk_size = row_chunk_size
 
+    def __validate_authentication(self):
+        _auth_vals = [
+            self.snowflake_user,
+            self.snowflake_password,
+            self.snowflake_account,
+            self.snowflake_database,
+            self.snowflake_warehouse,
+        ]
+
+        if any([not x for x in _auth_vals]):
+            raise ValueError(
+                "Missing authentication values! Make sure all `snowflake_*` values are provided at construction"
+            )
+
     @property
     def snowflake_warehouse(self):
         return self.__snowflake_warehouse