Lambda Function

Steps

In this example, we are going to deploy the source code in the directory Lambda.CreateBooking/ to your AWS account:

GitHub repository containing your source code

.
└── Lambda.CreateBooking/
    ├── ...
    └── Dockerfile

We want this Lambda function to be deployed under the application Kattehotell.

Step 1: Prepare an ECR repository

1. Navigate to repository SharedKontoInfrastruktur
2. Navigate to ./Shared/<application-name>/eu-west-1/ecr/main.tf
3. Update locals with new entries:

   locals {
     kattehotell_repos = toset([
       ...
       "create-booking",
     ])
   
     account_access = [
       local.accounts["BYM-DP-Kattehotell-Test"].id, 
       local.accounts["BYM-DP-Kattehotell-Prod"].id 
     ]
   }
   
   module "kattehotell_ecr" {
     for_each         = local.kattehotell_repos                                    
     source           = "git@github.com:BYM-IKT/terraform-aws-ecr.git?ref=v3"     
     application_name = "kattehotell"                                    
     service          = each.value
     account_access   = local.account_access 
   }
   
   output "kattehotell_ecr_repo" {
     value = module.kattehotell_ecr
   }
   

4. Create a Pull Request to Terraform apply this change. Terraform will provision a new ECR repository with the name ${application_name}-${service}. In our example, the resulting ECR repository will be named kattehotell-create-booking.

Step 2: Build and push Docker Image

Before you can proceed the ECR repository cannot be empty.

1. Create a GitHub Actions workflow file .github/workflows/deploy-to-test.yml:

   .
   ├── .github/
   │   └── workflows/
   │       └── deploy-to-test.yml
   └── Lambda.CreateBooking/
       ├── ...
       └── Dockerfile
   

   with the following content:
   ./.github/workflows/deploy-to-test.yml

   name: Deploy Lambda Function to TEST
   
   on:
     push:
       branches: [master]
     workflow_dispatch:
   
   jobs:
     build_push_image_to_shared:
       name: Build image and publish to ECR
       runs-on: ubuntu-latest
       permissions:
         id-token: write
         contents: read
       steps:
         - name: "Lambda.CreateBooking"
           uses: BYM-IKT/github-actions/build-and-push-image-to-ecr@master
           with:
             dockerfile-path: Lambda.CreateBooking/Dockerfile
             aws-account-id:  "<<AWS_ACCOUNT_ID>>"        
             ecr-name:        kattehotell-create-booking
             image-tags:      latest
   
     deploy_image_to_lambda_function_test:
       needs: [build_push_image_to_shared]
       name: "Deploy to TEST"
       uses: BYM-IKT/github-actions/.github/workflows/deploy-image-to-lambda.yml@v0
       with:
         environment:              testing
         aws-account-id-target:    <<AWS_ACCOUNT_ID>>
         ecr-name:                 kattehotell-create-booking
         image-tag-target:         latest
         image-tag-new:            test
         lambda-name:              test-kattehotell-create-booking
   

   where <<AWS_ACCOUNT_ID>> is replaced with the Id of your AWS Account.

2. Run the pipeline, which will build and push your Docker image to your ECR repository.

Why did deploy_image_to_lambda_function_test crash?

This pipeline will crash when running deploy_image_to_lambda_function_test as the Lambda function does not exist yet. We will fix this in the forthcoming steps.

Step 3: Create Lambda Function

Provision your Lambda Function referencing the ECR repository's URI as follows:

main.tf

module "application" {
  source      = "git@github.com:BYM-IKT/terraform-byks-module.git"
  environment = "test"
  ...
  lambda_functions = {
    create-booking = {
      ...
      ecr_uri   = data.terraform_remote_state.shared_ecr.outputs["create-booking"]
      image_tag = "test"
    }
  }
}

Create a Pull Request to Terraform apply this change.

Terraform will provision a new Lambda function named ${environment}-${application_name}-${service}. In our example, the resulting name of the Lambda function will be test-kattehotell-create-booking.

Step 4: Retry application pipeline

The whole pipeline created in Step 2 should work now. Try rerunning it.