chore: use os.getenv to simplify superset_config.py (#25016)

(cherry picked from commit 969cd66)

docker/pythonpath_dev/superset_config.py

@@ -22,41 +22,24 @@
 #
 import logging
 import os
-from typing import Optional
 
 from cachelib.file import FileSystemCache
 from celery.schedules import crontab
 
 logger = logging.getLogger()
 
+DATABASE_DIALECT = os.getenv("DATABASE_DIALECT", "postgresql")
+DATABASE_USER = os.getenv("DATABASE_USER", "superset")
+DATABASE_PASSWORD = os.getenv("DATABASE_PASSWORD", "superset")
+DATABASE_HOST = os.getenv("DATABASE_HOST", "db")
+DATABASE_PORT = os.getenv("DATABASE_PORT", "5432")
+DATABASE_DB = os.getenv("DATABASE_DB", "superset")
 
-def get_env_variable(var_name: str, default: Optional[str] = None) -> str:
- """Get the environment variable or raise exception."""
- try:
- return os.environ[var_name]
- except KeyError:
- if default is not None:
- return default
- else:
- error_msg = "The environment variable {} was missing, abort...".format(
- var_name
- )
- raise OSError(error_msg)
-
-
-DATABASE_DIALECT = get_env_variable("DATABASE_DIALECT")
-DATABASE_USER = get_env_variable("DATABASE_USER")
-DATABASE_PASSWORD = get_env_variable("DATABASE_PASSWORD")
-DATABASE_HOST = get_env_variable("DATABASE_HOST")
-DATABASE_PORT = get_env_variable("DATABASE_PORT")
-DATABASE_DB = get_env_variable("DATABASE_DB")
-
-EXAMPLES_USER = get_env_variable("EXAMPLES_USER")
-EXAMPLES_PASSWORD = get_env_variable("EXAMPLES_PASSWORD")
-EXAMPLES_HOST = get_env_variable("EXAMPLES_HOST")
-EXAMPLES_PORT = get_env_variable("EXAMPLES_PORT")
-EXAMPLES_DB = get_env_variable("EXAMPLES_DB")
-
+EXAMPLES_USER = os.getenv("EXAMPLES_USER", "examples")
+EXAMPLES_PASSWORD = os.getenv("EXAMPLES_PASSWORD", "examples")
+EXAMPLES_HOST = os.getenv("EXAMPLES_HOST", "db")
+EXAMPLES_PORT = os.getenv("EXAMPLES_PORT", "5432")
+EXAMPLES_DB = os.getenv("EXAMPLES_DB", "examples")
 
 # The SQLAlchemy connection string.
 SQLALCHEMY_DATABASE_URI = (
@@ -71,10 +54,10 @@ def get_env_variable(var_name: str, default: Optional[str] = None) -> str:
  f"{EXAMPLES_HOST}:{EXAMPLES_PORT}/{EXAMPLES_DB}"
 )
 
-REDIS_HOST = get_env_variable("REDIS_HOST")
-REDIS_PORT = get_env_variable("REDIS_PORT")
-REDIS_CELERY_DB = get_env_variable("REDIS_CELERY_DB", "0")
-REDIS_RESULTS_DB = get_env_variable("REDIS_RESULTS_DB", "1")
+REDIS_HOST = os.getenv("REDIS_HOST", "redis")
+REDIS_PORT = os.getenv("REDIS_PORT", "6379")
+REDIS_CELERY_DB = os.getenv("REDIS_CELERY_DB", "0")
+REDIS_RESULTS_DB = os.getenv("REDIS_RESULTS_DB", "1")
 
 RESULTS_BACKEND = FileSystemCache("/app/superset_home/sqllab")