feat: reduce sourcemaps and visualize dep tree

[rehanvdm]

This PR adds two features

Includng reduces sourcemaps

Excluding sourcemaps and shipping them to your third-party provider is great, but for Lambdas using CloudWatch, you have to include them to get meaningful traces.

This PR shows how you can drastically reduce the source maps by excluding anything from node_modules/ shrinking the souremap file from 34K to 2.2K.

Size Before

rehanvandermerwe@Rehans-MBP lambda-template % ls -lsha dist/products
total 120
 0 drwxr-xr-x  5 rehanvandermerwe  staff   160B Nov 19 11:46 .
 0 drwxr-xr-x  4 rehanvandermerwe  staff   128B Nov 19 11:46 ..
16 -rw-r--r--  1 rehanvandermerwe  staff   7.0K Nov 19 11:46 handler.js
72 -rw-r--r--  1 rehanvandermerwe  staff    34K Nov 19 11:46 handler.js.map
32 -rw-r--r--  1 rehanvandermerwe  staff    13K Nov 19 11:46 products.zip

Size After

rehanvandermerwe@Rehans-MBP lambda-template % ls -lsha dist/products                                                             
total 32
 0 drwxr-xr-x  5 rehanvandermerwe  staff   160B Nov 19 11:36 .
 0 drwxr-xr-x  4 rehanvandermerwe  staff   128B Nov 19 11:36 ..
16 -rw-r--r--  1 rehanvandermerwe  staff   7.0K Nov 19 11:36 handler.js
 8 -rw-r--r--  1 rehanvandermerwe  staff   2.2K Nov 19 11:36 handler.js.map
 8 -rw-r--r--  1 rehanvandermerwe  staff   3.9K Nov 19 11:36 products.zip

Visualize esbuild bundle

Similar to webpack, we can visualize our bundle, with a bit of work. It will open the bundle analysis as a HTML file after each build.

Example:

[bruuuuuuuce]

@rehanvdm thanks for this pr, this looks great! I pulled it down and tested it locally and everything looks good from my end. Really appreciate the feedback and analysis! I left one comment about a dependency, but once that is resolved I can merge this. Thanks again!

[bruuuuuuuce]

I believe this should be a dev dependency

[rehanvdm]

It can be yes, I mainly opened it to show what is possible. From the blog article, it seemed that you don't want to ship the sourcemaps with? So my idea with this PR wasn't that it will get merged, just to show that it is possible. Else if merged you would have to change parts of the article?

If not and you do want to merge it, by all means :). Please feel free to make the small change above or I can as well.

Nice article btw :). Also FYI, I created two issues that will/might turn into PRs upstream on the CDK:

• aws_lambda_nodejs: add option to visualize the esbuild bundle size aws/aws-cdk#28087
• aws_lambda_nodejs: exclude node_modules option from sourcemaps aws/aws-cdk#28088