How to use pdfkit in AWS Lambda?

Question

I'm using AWS Lambda to generate pdf file using a ninja2 template. I am trying to use pdfkit to convert my HTML into pdf. I realize pdfkit has an internal dependency - wkhtmltopdf which needs to be used as a binary or installed via a package manager. I am not sure how to make this work on AWS Lambda?

With my current template and python code using pdfkit, I am getting the following error -

{
  "errorMessage": "No wkhtmltopdf executable found: \"b''\"\nIf this file exists please check that this process can read it. Otherwise please install wkhtmltopdf - https://github.com/JazzCore/python-pdfkit/wiki/Installing-wkhtmltopdf",
  "errorType": "OSError",
.....
.....
}

Any ideas on how can I make pdfkit work on lambda?

Any suggestions for wkhtmltopdf replacements?

Thanks

Answer 1

I've made a simple demo on using PDFKit using Serverless framework using layer. Checkout https://medium.com/@crespo.wang/create-pdf-using-pdfkit-on-serverless-aws-lambda-with-layer-721ca86724b2

Answer 2

AWS Lambda has concept of Layers which allows you to upload your custom dependencies as a zip and then it will be available as it is installed on the box. For more information see here :

https://docs.aws.amazon.com/lambda/latest/dg/configuration-layers.html

In your case you could upload the binaries for wkhtmltopdf as layer and while creating lambda function, you could provide the layer to use.

Answer 3

There are multiple projects on GitHub used to run wkhtmltopdf on Lambda for example:

https://github.com/lubos/aws-lambda-wkhtmltopdf

https://github.com/dimiro1/lambda-wkhtmltopdf

https://github.com/jpaolin/aws-lambda-s3-wkhtmltopdf

Answer 4

Download the wkhtmltopdf binaries required for aws lambda from : https://wkhtmltopdf.org/downloads.html .

Add the zip file as layer to lambda and set the pdf kit config pointing to executable path in the zip file.(/opt/bin/wkhtmltopdf)