Integrating Aurora Serverless with Lambda Functions Using Python and PyMySQL

1. Change to the exercise_files directory:

   cd exercise_files/Section5-BackendLayer/
   

2. Zip the Lambda code to create a deployable file to Lambda:

   zip pymysql_function.zip pymysql_lambda.py
   

1. Run the following command, replacing <ROLE_ARN> with the ARN provided on the lab page:

aws lambda create-function
--memory-size 512
--function-name pymysql-function
--runtime python3.7
--handler pymysql_lambda.lambda_handler
--zip-file fileb://pymysql_lambda.zip
--role "<ROLE_ARN>"
--region us-east-1 ```

1. Create the Lambda layer with the provided zipped Python library:

   aws lambda publish-layer-version --layer-name pymysql-layer --zip-file fileb:///home/cloud_user/pymysql_lambda_layer.zip
   

After successful command execution, note the LayerVersionArn, as you'll need it in the next command.

1. Run the following command, replacing <LAYER_VERSION_ARN> with the ARN you just noted:

   aws lambda update-function-configuration --function-name pymysql-function --layers <LAYER_VERSION_ARN>
   

1. Log in to the AWS Management Console with the credentials provided on the lab page.
2. Create an RDS database, providing the following values:
   • With Standard create selected, set the Engine type to Aurora (MySQL Compatible)
   • Under Instance configuration > DB instance class, select Burstable classes (includes t classes) and db.t3.small
   • DB Cluster Identifier (your unique DB Cluster name)
   • Master Username, Master User Password (read password instructions carefully!)
   • Leave everything else at their default values

1. Navigate to Lambda.
2. Select your Lambda function's name.
3. In the Configuration section, click VPC and Edit.
4. Select the only available VPC.
5. Click the Subnets dropdown, and add the two available subnets.
6. For Security groups, choose the default security group.
7. Click Save.

1. Navigate to RDS.
2. Get the RDS Serverless database endpoint URL. Once you click on the database name, it should be under Connectivity & security tab.
3. Head over to the Lambda function and replace the DB host URL, username, and password with the actual values you set up when creating the RDS Serverless DB.
4. Once you're done, save your code and click Deploy.

1. In the Lambda code source properties, click the box to the right of Test and select Configure test event.
2. Keep the Hello World template selected, give your test event a name, and replace the test event body with {}.
3. Click Save.

1. Ensure your RDS Serverless database is in the available state. You can do that by heading to RDS and checking the status against your DB.
2. On the Lambda properties page for your function, make sure your test event in the top right corner is selected and hit Test. You should get a successful execution log and output of the SQL query embedded within the code.