christophshyper / presentation-lambda

Meetup presentation about AWS Lambda

presentation-lamda

Understanding AWS Lambda

Presentation about what AWS Lambda is and how to use it effectively.

DevOps Community Poland meetup #1

November 18th, 2019 EPAM, Opolska 114, Kraków, Poland

Live demo example

Prerequisites

• Bash
• Docker
• Python
• AWS CLI
• Terraform

• Can be run from WSL, requires only export DOCKER_HOST=tcp://localhost:2375 to connect to Docker running on Windows host.

Development

Example Python source code is in lambda-source/index.py.

To run it simply execute ./lambda.sh run example python3.7 '{"key": "value"}' 'my_value' in that directory.

Deployment

To see what will change go to lambda-infra directory and run terraform plan. Don't forget to run terraform init before that, but it's required only once.

To apply changes run terraform apply -parallelism=1.

Update

Uncomment line 10 in lambda-source/index.py so Lambda can return back the event that triggered it.

Run it locally to see how it will behave (as described above).

Run terraform plan to see what will be changed. You will always see Terraform needing to read package tags from data aws_s3_bucket_object source and aws_lambda_function needing to check source_code_hash. But when you apply it without any changes in Terrform log you'll see it actually did nothing.

To deploy your changes run terraform apply -parallelism=1 again.

Cleanup

After testing and playing with it cleanup all created resources by running terraform destroy and confirm with yes.