fix(GoogleCloudPlatform#10940): Replacing depracated before_first_request decorator (GoogleCloudPlatform#11007)

Author: m-strzelczyk

cloud-sql/mysql/sqlalchemy/app.py

@@ -81,12 +81,13 @@ def migrate_db(db: sqlalchemy.engine.base.Engine) -> None:
 # init_db lazily instantiates a database connection pool. Users of Cloud Run or
 # App Engine may wish to skip this lazy instantiation and connect as soon
 # as the function is loaded. This is primarily to help testing.
-@app.before_first_request
+@app.before_request
 def init_db() -> sqlalchemy.engine.base.Engine:
     """Initiates connection to database and its' structure."""
     global db
-    db = init_connection_pool()
-    migrate_db(db)
+    if db is None:
+        db = init_connection_pool()
+        migrate_db(db)
 
 
 @app.route("/", methods=["GET"])

cloud-sql/postgres/sqlalchemy/app.py

@@ -81,12 +81,13 @@ def migrate_db(db: sqlalchemy.engine.base.Engine) -> None:
 # init_db lazily instantiates a database connection pool. Users of Cloud Run or
 # App Engine may wish to skip this lazy instantiation and connect as soon
 # as the function is loaded. This is primarily to help testing.
-@app.before_first_request
+@app.before_request
 def init_db() -> sqlalchemy.engine.base.Engine:
     """Initiates connection to database and its structure."""
     global db
-    db = init_connection_pool()
-    migrate_db(db)
+    if db is None:
+        db = init_connection_pool()
+        migrate_db(db)
 
 
 @app.route("/", methods=["GET"])

cloud-sql/sql-server/sqlalchemy/app.py

@@ -73,11 +73,12 @@ def migrate_db(db: sqlalchemy.engine.base.Engine) -> None:
 # init_db lazily instantiates a database connection pool. Users of Cloud Run or
 # App Engine may wish to skip this lazy instantiation and connect as soon
 # as the function is loaded. This is primarily to help testing.
-@app.before_first_request
+@app.before_request
 def init_db() -> sqlalchemy.engine.base.Engine:
     global db
-    db = init_connection_pool()
-    migrate_db(db)
+    if db is None:
+        db = init_connection_pool()
+        migrate_db(db)
 
 
 @app.route("/", methods=["GET"])

compute/managed-instances/demo/app.py

@@ -39,11 +39,12 @@
 _cpu_burner = None
 
 
-@app.before_first_request
+@app.before_request
 def init():
     """Initialize the application."""
     global _cpu_burner
-    _cpu_burner = CpuBurner()
+    if _cpu_burner is None:
+        _cpu_burner = CpuBurner()
 
 
 @app.route("/")