feat(db): Change default alembic env.py to get connection string from env vars

db/env.py

@@ -1,6 +1,10 @@
+import os
 from logging.config import fileConfig
 
-from sqlalchemy import engine_from_config
+# #3 Get connection string from env vars instead of a Git-committed env.py
+# http://allan-simon.github.io/blog/posts/python-alembic-with-environment-variables/
+# from sqlalchemy import engine_from_config
+from sqlalchemy import engine_from_config, create_engine
 from sqlalchemy import pool
 
 from alembic import context
@@ -26,6 +30,18 @@ target_metadata = None
 # ... etc.
 
 
+def get_url():
+    # #3 Get connection string from env vars instead of a Git-committed env.py
+    # http://allan-simon.github.io/blog/posts/python-alembic-with-environment-variables/
+    return "%s://%s:%s@%s/%s" % (
+        os.getenv("DB_DIALECTDRIVER", "mysql"),
+        os.getenv("DB_USER", "kodi-timekeeper"),
+        os.getenv("DB_PASSWORD", "kodi-timekeeper"),
+        os.getenv("DB_HOST", "localhost"),
+        os.getenv("DB_NAME", "kodi-timekeeper"),
+    )
+
+
 def run_migrations_offline():
     """Run migrations in 'offline' mode.
 
@@ -38,7 +54,10 @@ def run_migrations_offline():
     script output.
 
     """
-    url = config.get_main_option("sqlalchemy.url")
+    # #3 Get connection string from env vars instead of a Git-committed env.py
+    # http://allan-simon.github.io/blog/posts/python-alembic-with-environment-variables/
+    # url = config.get_main_option("sqlalchemy.url")
+    url = get_url()
     context.configure(
         url=url,
         target_metadata=target_metadata,
@@ -57,11 +76,9 @@ def run_migrations_online():
     and associate a connection with the context.
 
     """
-    connectable = engine_from_config(
+    # #3 Get connection string from env vars instead of a Git-committed env.py
-        config.get_section(config.config_ini_section),
+    # http://allan-simon.github.io/blog/posts/python-alembic-with-environment-variables/
-        prefix="sqlalchemy.",
+    connectable = create_engine(get_url())
-        poolclass=pool.NullPool,
-    )
 
     with connectable.connect() as connection:
         context.configure(