Connecting to Cloud SQL - Postgres

Before you begin

1. If you haven't already, set up a Python Development Environment by following the python setup guide and create a project.

2. Create a 2nd Gen Cloud SQL Instance by following these instructions. Note the connection string, database user, and database password that you create.

3. Create a database for your application by following these instructions. Note the database name.

4. Create a service account with the 'Cloud SQL Client' permissions by following these instructions. Download a JSON key to use to authenticate your connection.

5. 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>:<INSTANCE-NAME>'
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 has been downloaded, use the following commands to create the /cloudsql directory and give the user running the proxy the appropriate permissions:

sudo mkdir /cloudsql
sudo chown -R $USER /cloudsql

Once the /cloudsql directory 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

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

Deploy to Cloud Run

See the Cloud Run documentation for more details on connecting a Cloud Run service to Cloud SQL.

1. Build the container image:

gcloud builds submit --tag gcr.io/[YOUR_PROJECT_ID]/run-sql

2. Deploy the service to Cloud Run:

gcloud beta run deploy run-sql --image gcr.io/[YOUR_PROJECT_ID]/run-sql

Take note of the URL output at the end of the deployment process.

3. Configure the service for use with Cloud Run

gcloud beta run services update run-mysql \
    --add-cloudsql-instances [INSTANCE_CONNECTION_NAME] \
    --set-env-vars CLOUD_SQL_CONNECTION_NAME=[INSTANCE_CONNECTION_NAME],\
      DB_USER=[MY_DB_USER],DB_PASS=[MY_DB_PASS],DB_NAME=[MY_DB]

Replace environment variables with the correct values for your Cloud SQL instance configuration.

This step can be done as part of deployment but is separated for clarity.

4. Navigate your browser to the URL noted in step 2.

For more details about using Cloud Run see http://cloud.run. Review other Python on Cloud Run samples.