A simple bash script to demonstrate the steps required in the CI

example_ci.sh

# 1. Build zip file of compiled source code
zip_path="PATH_TO_COMPILED_ZIPFILE"

# 2. Upload zip file to AWS S3 so that we can point to it when calling `update-function-code`
bucket="lambda-zips"
function_name="test-function"
commit=(git rev-parse HEAD)
# This destination key is important because it will determine where we look for code when calling `update-function-code`
# You want to include this information about the current state of the code in it. a git SHA isn't a bad idea
dst_key="${function_name}/${commit}.zip"
s3_uri="s3://${bucket}/${dst_key}"


# The "progress" lines are SUPER noisy.
aws s3 cp --no-progress "${zip_path}" "${s3_uri}" 

lambda-test-function-preview.yaml

apiVersion: lambda-deployment.keeptruckin.com/v1
kind: LambdaDeployment
metadata:
  name: lambda-deployment-test-function-preview
spec:
  # We control the lambda environment using the ARN
  functionARN: arn:aws:lambda:us-east-1:123:function:test-function-preview
  # These will be used to construct the key for the zip file uploaded to S3
  functionName: test-function
  # The SHA of the current HEAD commit
  commit: 8cc06dbec558fd94d9b40da92e347a34f454df61

lambda_deployment_crd.go

// LambdaDeploymentSpec defines the desired state of LambdaDeployment
type LambdaDeploymentSpec struct {
    // The ARN of the function that is to be updated
    FunctionARN string `json:"functionARN"`
    // The function name, this is used purely for building the S3 path
    FunctionName string `json:"functionName"`
    // The commit used to build the zip file uploaded to S3
    // Note that the controller expects the zip file to be in the following locations
    // s3://lambda-zip/FUNCTION_NAME>/<COMMIT>.zip
    Commit string `json:"commit"`
}

// LambdaDeployment is the Schema for the lambdadeployments API
type LambdaDeployment struct {
    // metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
    metav1.TypeMeta   `json:",inline"`
    metav1.ObjectMeta `json:"metadata,omitempty"`

    Spec   LambdaDeploymentSpec   `json:"spec,omitempty"`
    Status LambdaDeploymentStatus `json:"status,omitempty"`
}

reconcile_loop.go

func (r *LambdaDeploymentReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
    ld := &LambdaDeployment{}

    err := r.Get(ctx, req.NamespacedName, ld)
    switch e := err; {
    case apierrors.IsNotFound(e):
        // This corresponds to a DELETE action so we can ignore it
        log.Println("LambdaDeployment is deleted... Doing nothing?")
        return ctrl.Result{}, nil
    case e != nil:
        log.Printf("Could not GET the LambdaDeployment: %s", err)
        return ctrl.Result{}, nil
    }

    // This is the "lambda.Client" from "github.com/aws/aws-sdk-go-v2/service/lambda"
    _, err = r.LambdaClient.UpdateFunctionCode(ctx, &lambda.UpdateFunctionCodeInput{
        FunctionName: &ld.Spec.FunctionARN, // The ARN is the input to "FunctionName" parameter confusingly
        S3Bucket:     "lambda-zips",
        S3Key:        fmt.Sprintf("%s/%s.zip", ld.Spec.FunctionName, ld.Spec.Commit),
    })


    return ctrl.Result{}, nil
}