Cannot import package in AWS lambda with Nodejs14.x ES module

Question

I have a layer where the path of node_modules is nodejs/node14/node_modules.

Using that layer, and I try to import a package in a Lambda function, say 'aws-cloudfront-sign', like this:

import cfsign from 'aws-cloudfront-sign'

I got error message

Cannot find package 'aws-cloudfront-sign' imported from /var/task/signer.js\nDid you mean to import aws-cloudfront-sign/lib/cloudfrontUtil.js?

But if I import the package like this:

import cfsign from '/opt/nodejs/node14/node_modules/aws-cloudfront-sign/lib/cloudfrontUtil.js'

It succeeds.

Do you know why? How could I import the package correctly?

Answer 1

2023 Update:

Note that the solution below was for a Node 14 problem with a specific SDK version, per the question. Imports for AWS SDK v3 are now supported in Node 18+. Using the below solution for other Node/SDK versions likely will not work.

See the AWS post here and the discussion ESM imports from NODE_PATH are not available when using Lambda's Node Runtime 14 and 16.

End update

---

This appears to be a bug. It is occurring with layers and the SDK. There are are a number of similar open issues on Github:

Nodejs Lambda: Cannot find package 'aws-sdk'

Cannot find package when using ES Module and Lambda Layer

ES6 imports don't work in @aws-sdk/client-iotsitewise

As you have worked out, the only workaround at present seems to be the use of absolute paths. E.g.:

import { DynamoDB } from 'aws-sdk;'

fails, whereas

import AWS from '/var/runtime/node_modules/aws-sdk/lib/aws.js';
const { DynamoDB } = AWS;

will work.

I suggest you add your voice to an existing open issue to help ensure it gets attention.

Answer 2

I was running across a similar issue. I wasn't able to import my Dynomdb in my lambda function.

I ended up doing something like this.

import { DynamoDBClient } from "@aws-sdk/client-dynamodb";
import {
  DynamoDBDocumentClient,
  PutCommand,
} from "@aws-sdk/lib-dynamodb";

const client = new DynamoDBClient({});

const dynamo = DynamoDBDocumentClient.from(client);

This will create a new client that you can use to run the various commands.

See documentation here: AWS SDK for JavaScript DynamoDB

Check out these Client Documentation for DynamoDB enter link description here