AWS Lambda Image Resizer in S3

Example of a Image resizer using AWS lambda and S3

This is a node implementation of an image resizer while a I took the AWS Lambda and the Serverless Framework course.

This is an interesting exercise since it uses a 'native' library for image resizing: Sharp

 +--------+                  +----------+                 +--------+
 |        |                  |          |                 |        |
 |   S3   | +--------------> |  Lambda  | +-------------> |   S3   |
 |        |      trigger     |          |     push        |        |
 +--------+                  +----------+                 +--------+

 new image                    creates a                    new thumbnail
 uploaded                     thumbnail                    created

Deploy

The deploy is done using the Serverless Framework .

sls deploy -v

You need Serverless to be installed and configured. Additionally you may need to install some plugins for size reduction,

# npm install serverless-plugin-include-dependencies serverless-plugin-common-excludes --save-dev
yarn add --dev serverless-plugin-include-dependencies serverless-plugin-common-excludes

Since Sharp library has native extensions, you need Linux binaries when deploying (AWS runs on linux). If your local machine runs Linux your are fine. Otherwise read https://sharp.pixelplumbing.com/install#aws-lambda

Credits

based on https://github.com/serverless/examples/tree/master/aws-node-dynamic-image-resize but simpler.