lambda-resize-image

An AWS Lambda Function to resize images automatically with API Gateway and S3 for imagemagick tasks. When an image is called on AWS Api Gateway, this package will resize it and send it to the S3.

Contents

• lambda-resize-image
  • Contents
  • Requirements
  • What is it?
  • Description
  • Features
  • Instalation
    • AWS credentials
    • Deploy to Amazon AWS
  • Usage (image restrictions resize)
    • Example URL usage
  • Environment variables
  • Local development
    • Example request
      • Configuration Parameters
  • Feedback
  • Contributing
  • License
  • Author

Requirements

• Node.js - AWS Lambda supports versions of 8.10 or above.

What is it?

It's AWS Lambda, which is a compute service that lets you run code without provisioning or managing servers.

Read more about AWS Lambda.

Description

The combination of API Gateway and Lambda is very powerful. It allows you to build some complex functionalities without maintaining any virtual machines yourself. Lambda can be hooked up to many other (AWS) Services including S3. That's why I decided to build an AWS Lambda Function to resize images automatically with API Gateway and S3 for imagemagick tasks. When an image is called on AWS S3 bucket (via API Gateway), this package will resize it and send it to the S3 before redirecting you to the new path of the image (aws bucket url or CDN).

Features

• Use Serverless Framework
• Use Serverless Webpack
• Use Serverless Offline
• The image conversion endpoint by API Gateway or cloudfront URL.

Instalation

First, add Serverless globally:

npm install -g serverless

Then, clone the repository into your local environment:

git clone https://github.com/apoca/lambda-resize-image
cd lambda-resize-image
npm install

Modify and set the .env.example to env.yml with your data. (You are supposed to have already configured your local variables)).

AWS credentials

To run local development you also might need to configure you aws credentials, or you can set them to what I've shown below.

Deploy to Amazon AWS

You can also check if you have everything installed in the correct way:

$ serverless

To deploy from your environment to Amazon AWS, you must:

$ serverless deploy

Then, serverless will package, validate and upload your stack to Amazon AWS. It will probably look like this:

Serverless: Packaging service...
Serverless: Uploading CloudFormation file to S3...
Serverless: Uploading artifacts...
Serverless: Uploading service .zip file to S3 (1.52 KB)...
Serverless: Validating template...
Serverless: Updating Stack...
Serverless: Checking Stack update progress...
..............
Serverless: Stack update finished...
Service Information
service: resizeS3Image
stage: development
region: eu-west-1
stack: resizeS3Image-development
api keys:
  None
endpoints:
  GET - https://<api_key_here>.execute-api.eu-west-1.amazonaws.com/development/{any+}
functions:
  handler: resizeS3Image-development-handler
Serverless: Removing old service artifacts from S3...

When upload to AWS Lambda, the project will bundle only needed files - no dev dependencies will be included.

Usage (image restrictions resize)

To restrict the dimensions, we put a const var in the handle.js:

const ALLOWED_DIMENSIONS = {
  width: 1800,
  height: 1800
};

You can also change the url endpoint https://<api_key_here>.execute-api.eu-west-1.amazonaws.com/development/{any+} to another one more tiny and cachable (cloudfront), you can also configure in you Api Gateway (lambda service) a Custom Domain Name.

Example URL usage

https://api.yourdomain.com/<KEY_S3_IMAGE_HERE>?width=<WIDTH>&height=<HEIGHT>

Environment variables

• URL - AWS URL S3 bucket or your CDN url to the BUCKET. (required)

• BUCKET - AWS S3 bucket. (required)

  Environment variables for serverless

  • AWS_ACCESS_KEY_ID - AWS key
  • AWS_SECRET_ACCESS_KEY - AWS Secret

Local development

1. $ npm i -g serverless
2. $ npm i
3. brew install imagemagick
4. $ serverless offline start

Note that you will need to be into the root repository. The last command (4.) will spin up an serverless-offline version of an API Gateway, that will simulate the real one. Once it is running, you can see all the requests on your command line.

Example request

http://localhost:3000<YOUR_KEYNAME_TO_IMAGE>?width=<WIDTH>&height=<HEIGHT>

Configuration Parameters

Parameter	type	description
width	Integer	Required. Will resize image via imagemagic resize.
height	Integer	Optional. Will resize image via imagemagic crop.

Feedback

We'd love to get feedback on how you're using lambda-resize-image and things we could add to make this tool better. Feel free to contact us at [email protected]

Contributing

If you'd like to contribute to the project, feel free to submit a PR. See more: CODE_OF_CONDUCT.md

License

This project is licensed under the MIT License - see the LICENSE.md file for details

Author

• Miguel Vieira - Initial work - apoca

See also the list of contributors who participated in this project.