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Bug: Middy requires special flag in `tsconfig.json` to be imported as esm

See original GitHub issue

Bug description

when using middy i get the following error TypeError: core_1.default is not a function

Possible Solution

updating the tsconfig.json with "esModuleInterop": true solved the problem as suggested in middy’s github Issue https://github.com/middyjs/middy/issues/203

Environment

Powertools version used: 0.2.0
Packaging format (Layers, npm): npm
AWS Lambda function runtime: node v14

Issue Analytics

State:
Created 2 years ago
Comments:7 (4 by maintainers)

Top GitHub Comments

2reactions

willfarrellcommented, Feb 15, 2022

Using ESM by default in Middy was the plan. However …

(a) Recent discoveries that Lambda with ESM cannot access node_modules pre-bundled in the runtime or shared in a lambda layer has made us stop and rethink. This isn’t documented anywhere that I know of 😦. I’ve reported this regression to AWS Support and was told to use v3 of the SDK instead.

(b) We would consider migrating to using v3 of the SDK (I even tried a year ago), however, RDS.Signer is not implemented yet (https://github.com/aws/aws-sdk-js-v3/issues/1823 @AllanZhengYP). Using v3 of the SDK would increase lambda bundle size compared to v2 of the SDK. I would suggest AWS pre-bundle all v3 packages in the runtime (https://github.com/aws/aws-sdk-js-v3/issues/2149), but this wouldn’t help with ESM support because lambda handlers wouldn’t be able to access them anyways (a) 🤷

Based on the current state of ESM support from AWS outlined above, the new plan for middy@3 will be to continue providing CommonJS for another year sadly. We’re going to wait (2-3 week) and see if ((a OR b*2) AND c) are resolved before making a final decision and mint a beta release.

Cross posted from: https://github.com/middyjs/middy/issues/584

cc @lmammino

2reactions

ijemmycommented, Feb 15, 2022

Put this on-hold as this will be solved when we upgrade to middy v3.

@saragerion I wonder if we should make this note in our doc? (for all utils, in middy tab). On the other hand, this is middy specific and middy v3 will be released when NodeJS16 is supported in Lambda. We can wait to just upgrade once.

I’m inclined to wait and upgrade as we aren’t out of beta yet. What’s your thought?

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