Amplify Gen 2 - DynamoDB table write from Lambda function

To set up your backend so that the DynamoDB table name created by your Amplify model is passed to the Lambda function as an environment variable, rather than hardcoding it, you can follow these best practices:

1. Use environment variables: Instead of hardcoding the DynamoDB table name in your Lambda function code, use an environment variable. This is considered a best practice for configuration management.

2. Set the environment variable during deployment: When deploying your Lambda function, set the environment variable with the DynamoDB table name. This can typically be done through your Infrastructure as Code (IaC) tool or deployment script.

3. Use AWS CloudFormation or CDK: If you're using AWS CloudFormation or the AWS CDK to define your infrastructure, you can use these tools to dynamically reference the DynamoDB table name and set it as an environment variable for your Lambda function.

4. Amplify CLI: If you're using the Amplify CLI, you can modify the Lambda function configuration to include the environment variable. The Amplify CLI can help you manage this configuration.

5. Access in Lambda: In your Lambda function code, you can then access this environment variable to get the table name, rather than using a hardcoded value.

Here's a general approach you could follow:

1. When defining your Lambda function (either through Amplify CLI or other IaC tools), set an environment variable, e.g., 'DDB_TABLE_NAME'.

2. In your Lambda function code, access this environment variable:

   const tableName = process.env.DDB_TABLE_NAME;

3. Use this tableName variable when interacting with DynamoDB in your Lambda function.

This approach allows for more flexibility and easier management of your resources, as you can change the table name without modifying your function code. It also adheres to the principle of keeping configuration separate from code, which is a best practice in software development.

Remember to ensure that your Lambda function has the necessary permissions to access the DynamoDB table. This is typically managed through the function's execution role.

Sources
Tutorial: Using Lambda with API Gateway - AWS Lambda
Step 2: Write data to a DynamoDB table - Amazon DynamoDB
aws-lambda-dynamodb - AWS Solutions Constructs