utils.py

import yaml
import sqlalchemy
from sqlalchemy import create_engine


def load_config(config_file: str) -> dict:
    """Read the YAML config file

    Args:
        config_file (str): YAML configuration file path
    """
    with open(config_file, "r") as stream:
        try:
            return yaml.safe_load(stream)
        except yaml.YAMLError as exc:
            print(exc)
            
            
def get_db_engine(config_file: str, db_name=None) -> sqlalchemy.engine.base.Engine:
    """Create a SQLAlchemy Engine instance based on the config file

    Args:
        config_file (str): Path to the config file
        db_name (str, optional): Name of the database to connect to. Defaults to None.

    Returns:
        sqlalchemy.engine.base.Engine: SQLAlchemy Engine instance for the database

    """
    # load the configurations
    config = load_config(config_file=config_file)
    # Database connection configuration
    dbms = config['database']['dbms']
    db_host = config['database']['host']
    db_port = config['database']['port']
    db_user = config['database']['user']
    db_pass = config['database']['password']
    db_name = db_name if db_name else ''
    
    # creating SQLAlchemy Engine instance
    con_str = f'postgresql://{db_user}:{db_pass}@{db_host}:{db_port}/{db_name}'
    db_engine = create_engine(con_str, echo=True, future=True)
    
    return db_engine