fredriv/serverless-lambda-workshop

Workshop on creating applications using Serverless Framework and AWS Lambda

Serverless Lambda workshop

Workshop on creating applications using Serverless Framework and AWS Lambda.

Slides can be found here: https://www.slideshare.net/fredriv/building-applications-with-serverless-framework-and-aws-lambda-javazone-2019

Setup

• Install npm: https://www.npmjs.com/get-npm
• Install Serverless command line tools: npm install -g serverless
• Install Docker and Docker Compose
• Pre-fetch Lambda Docker images:
  • docker image pull localstack/localstack:0.11.5
  • docker image pull lambci/lambda:python3.8
• Install Python 3 and pip:
  • Mac: https://wsvincent.com/install-python3-mac/
• Install LocalStack AWS CLI wrapper: pip install awscli-local

Running on local machine

To run the exercises on your local machine, we will use LocalStack to emulate AWS services.

• Start LocalStack with docker-compose up from the top-level directory
• On Mac, you may need to run TMPDIR=/private$TMPDIR docker-compose up

Debugging

• To enable debug output in LocalStack, run with DEBUG=1 docker-compose up
• Debugging Serverless Framework commands: SLS_DEBUG=* sls deploy --verbose

LocalStack Gotchas

Full redeploy and undeploy does not work properly in LocalStack. You need to either redeploy individual functions (sls deploy function -f <function-name>) or restart LocalStack and do a fresh sls deploy.

AWS CLI wrapper (awslocal) on Windows

If you install awslocal (pip install awscli-local), it does not install a Windows script. See: localstack/awscli-local#6 for a script you can use. Save this as a Batch file in the Python environments Scripts directory.

Host configuration on Docker Machine

On Docker Machine, the endpoint will not be served on localhost. This requires two changes. Set the environment variable LOCALSTACK_HOST to the hostname or IP, e.g.: export LOCALSTACK_HOST=192.168.99.100 or set LOCALSTACK_HOST=192.168.99.100. Second you must update the serverless.yml files in each project under custom.localstack add a host key, and set its value to http://{hostname_or_ip}

This is used by awslocal, and when outputting endpoint information in the Localstack client.

Running on AWS (optional)

• Create a free AWS account: https://portal.aws.amazon.com/billing/signup#/start
• Create a new user for the workshop: https://console.aws.amazon.com/iam/home#/users$new
  • Enable both Programmatic access and AWS Management Console access
  • On next page, choose Attach existing policies directly
    • Select e.g. AdministratorAccess or AWSLambdaFullAccess
  • Navigate through next pages and Create user
  • On the result page, copy the Access key ID and Secret access key, or download the credentials CSV-file
• Install the AWS command line tools: https://aws.amazon.com/cli/
• In each exercise directory:
  • Comment out the serverless-localstack plugin in the serverless.yml files

Put the access and secret keys from above in the AWS credentials file, ~/.aws/credentials:

[default]
aws_access_key_id     = <your-access-key>
aws_secret_access_key = <your-secret-key>

or configure them in a different AWS profile if you already have a [default] profile, e.g. [workshop]. For more details, see https://docs.aws.amazon.com/cli/latest/userguide/cli-configure-files.html