node-canvas-lambda

A node-canvas (and chart.js) layer for AWS Lambda

Build

Build new layers using the Dockerfile and copy them to the build folder. Be sure to have Docker installed then run the following command:

make build

The default version of Nodejs is 16. To build for a different node version set the NODE_VERSION:

make build NODE_VERSION=14

Publish

Upload the layers to AWS into your default region. This will build the layers if they have not already been built.

make publish

Test

A lambda image (e.g. public.ecr.aws/lambda/nodejs:16-arm64 ) can be used to test the layers by loading the layers and running a simple lambda handler that uses canvas.

The following command will unzip the layers and mount the layer folders into to the /opt/ folder of the lambda container and then run the test.js handler:

make test

If the test worked correctly the output should be a data URI. e.g.: "data:image/png;base64,iVBORw0KGgoAAAA.... You can copy the URI and paste it into our browser's url bar to see the image.

Architecture

The default architecture for these layers are ARM. If you're function uses amd64 architecute you shouldn't have any issues. If you're using x86-64 you'll need to checkout the x86-64 branch and run make build.

Debug

The build image can be used to debug any issues with the layers.

Use make debug to start an interactive bash session in the container where you can use ldd or lddtree to examine the canvas.node binary:

ldd nodejs/node_modules/canvas/build/Release/canvas.node