Serverless Samples

SAM Deploy

Deploys the SAM application to AWS. Runs build, validation, and deploy steps in sequence.

Steps

1. Validate the template

   sam validate --lint
   

   Fix any validation errors before proceeding.

2. Build the application

   sam build
   

   If the build fails due to Python version mismatch, retry with:

   sam build --use-container
   

3. Check for YAML issues Verify no duplicate keys were introduced by automated edits:

   python3 -c "import yaml; yaml.safe_load(open('template.yaml'))"
   

4. Deploy For standard (non-production) deploys:

   sam deploy
   

   This uses settings from samconfig.toml. Ensure confirm_changeset = false for automated deploys.

   For first-time or guided deploys:

   sam deploy --guided
   

5. Verify deployment Check the CloudFormation stack status:

   aws cloudformation describe-stacks --stack-name <STACK_NAME> --query 'Stacks[0].StackStatus'
   

Troubleshooting

• First deploy KMS/CreateGrant failure: Delete the failed stack with sam delete and redeploy.
• Multiple GSI changes: CloudFormation only supports adding/removing one GSI per update. Delete and redeploy if multiple GSI changes are needed.
• Build errors: Check that the Python version on PATH matches the runtime specified in template.yaml.

Post-Deploy

• Run seed scripts if this is a fresh deployment: bash scripts/seed.sh (if present).
• Check CloudWatch Logs for any startup errors in the deployed functions.

Source: aws-samples/serverless-samples — distributed by TomeVault.