Deploy an AWS Lambda function in your Development Environment

This tutorial will show you how to deploy a development environment in Okteto that contains an AWS Lambda function with Okteto.

Prerequisites

• Access to an Okteto instance
• Access to an AWS account with the permissions to create IAMs

Step 1: Create an IAM user

The IAM user that you use with AWS SAM must have sufficient permissions to make necessary AWS service calls and manage AWS resources.

The following permissions will enable you to complete this tutorial:

• AWSCloudFormationFullAccess
• IAMFullAccess
• AWSLambda_FullAccess
• AmazonAPIGatewayAdministrator
• AmazonS3FullAccess

Once the user has been created, generate a set of access keys, and save them file locally.

In order for the installer to be able to use this keys, we need to add them as Okteto Variables. Use AWS_ACCESS_KEY_ID as the name for the variable that contains the access ID, and AWS_SECRET_ACCESS_KEY as the name for the variable that contains the access key.

You can add them as User Variables, or Admin Variables if you want everyone in your Okteto instance to be able to use them.

Step 2: Define a custom installer image

We are going to use the SAM CLI to build and deploy our AWS Lambda function. SAM is a open-source framework that you can use to build serverless applications in AWS.

You can directly install the SAM CLI in your Okteto manifest. However, this will make every deployment slower than it needs to be. Instead, we recommend that you create your own installer image with sam(and any other tool you might need) preinstalled.

To do this, first create a Dockerfile:

# Dockerfile

FROM python:3.9-buster

RUN apt-get update && \ 
  apt-get install -y unzip curl && \
  curl -o /tmp/awscli-exe-linux-x86_64.zip -L https://awscli.amazonaws.com/awscli-exe-linux-x86_64.zip && \
  unzip /tmp/awscli-exe-linux-x86_64.zip -d /tmp/aws-cli && \
  sh /tmp/aws-cli/aws/install && \
  aws --version && \
  curl -o /tmp/aws-sam-cli-linux-x86_64.zip -L https://github.com/aws/aws-sam-cli/releases/latest/download/aws-sam-cli-linux-x86_64.zip && \
  unzip /tmp/aws-sam-cli-linux-x86_64.zip -d /tmp/sam-installation && \
  sh /tmp/sam-installation/install && \
  sam --version

Then add a build section to your Okteto manifest to tell Okteto to build the image on demand when deploying your development environment:

#okteto.yaml
# okteto.yaml
build:
  sam:
    context: .
    dockerfile: Dockerfile

Step 3: Create your Okteto manifest

In this tutorial, we are only going to deploy the AWS Lambda function to keep it simple. In the real world, you'd typically include both containers and AWS Lambda functions as part of your Development Environment.

In order to deploy a function in Okteto, you need to create an Okteto manifest similar to the one below:

# okteto.yaml
build:
  sam:
    context: .
    dockerfile: Dockerfile
deploy:
  image: ${OKTETO_BUILD_SAM_IMAGE}
  commands:
    - name: build function
      command: sam build
    - name: deploy function
      command: |
        sam deploy --no-confirm-changeset --no-fail-on-empty-changeset --s3-prefix "${OKTETO_NAMESPACE}" --stack-name "${OKTETO_NAMESPACE}-okteto-lambda" --resolve-s3
        FUNCTION_URL=$(aws cloudformation describe-stacks --region us-east-1 --stack-name ${OKTETO_NAMESPACE}-okteto-lambda --query "Stacks[0].Outputs[0].OutputValue" --output text)
        
        # use external resources to display the URL the Okteto UI
        echo "OKTETO_EXTERNAL_LAMBDA_ENDPOINTS_FUNCTION_URL=$FUNCTION_URL" >> $OKTETO_ENV
destroy:
  image: ${OKTETO_BUILD_SAM_IMAGE}
  commands:
  - name: destroy function
    command: sam delete --no-prompts --stack-name "${OKTETO_NAMESPACE}-okteto-lambda" --region us-east-1
external:
  lambda:
    icon: function
    endpoints:
    - name: function

info

This manifest takes advantage of our External Resources feature manage the lifecycle of external resources as part of your Okteto development environment. Learn more about External Resources here.

Details:

• The deploy.image field tells Okteto to use the image we defined on the build section.
• The deploy.commands section includes all the commands needed to build and deploy the function.
• The destroy section includes the commands needed to destroy the Lambda function. This will be invoked when the environment or the namespace are destroyed.

Step 4: Deploy your Development Environment

Commit the Okteto manifest that we created in the previous step to your repository, and push the changes to a remote branch. Then, deploy your Development Environment directly from the Okteto UI.

After a few seconds, your Development Environment will be fully deployed and your AWS Lambda function will be up and running. Every time you redeploy the Development Environment, the AWS Lambda function will be recreated with your latest code.

The source code used on this tutorial is available here.

Next steps

Congratulations, you just deployed your first AWS Lambda function in Okteto 🚀.

Head over to our getting started guides for Go, ASP.NET, Java, Node.js, PHP, Python, or Ruby to see how to integrate it with the rest of your applications.