Connecting to Cloud SQL - MySQL

Before you begin

If you haven't already, set up a Python Development Environment by following the python setup guide and create a project.
Create a 2nd Gen Cloud SQL Instance by following these instructions. Note the connection string, database user, and database password that you create.
Create a database for your application by following these instructions. Note the database name.
Create a service account with the 'Cloud SQL Client' permissions by following these instructions. Download a JSON key to use to authenticate your connection.
Use the information noted in the previous steps:

export GOOGLE_APPLICATION_CREDENTIALS=/path/to/service/account/key.json
export CLOUD_SQL_CONNECTION_NAME='<MY-PROJECT>:<INSTANCE-REGION>:<MY-DATABASE>'
export DB_USER='my-db-user'
export DB_PASS='my-db-pass'
export DB_NAME='my_db'

Note: Saving credentials in environment variables is convenient, but not secure - consider a more secure solution such as Cloud KMS to help keep secrets safe.

Running locally

To run this application locally, download and install the cloud_sql_proxy by following the instructions here.

Once the proxy is ready, use the following command to start the proxy in the background:

./cloud_sql_proxy -dir=/cloudsql --instances=$CLOUD_SQL_CONNECTION_NAME --credential_file=$GOOGLE_APPLICATION_CREDENTIALS

Note: Make sure to run the command under a user with write access in the /cloudsql directory. This proxy will use this folder to create a unix socket the application will use to connect to Cloud SQL.

Next, setup install the requirements into a virtual enviroment:

virtualenv --python python3 env
source env/bin/activate
pip install -r requirements.txt

Finally, start the application:

python main.py

Navigate towards http://127.0.0.1:8080 to verify your application is running correctly.

Google App Engine Standard

To run on GAE-Standard, create an App Engine project by following the setup for these instructions.

First, update app.yaml with the correct values to pass the environment variables into the runtime.

Next, the following command will deploy the application to your Google Cloud project:

gcloud app deploy