Amazon web services – Require is not defined in lambda function

First of all, my apologies if this is very trivial but every solution I tried just gave errors.

In short I am new to the aws enviroment and choose a dynamodb to set up as database. I used a lamdba function to be able to batch write data from anywhere to the cloud.

It took some time but I got it all working, however by mistake I chose (or rather used the default) db location us-east-1. Now long story short for legal reasons the data should be in Europe. So I just copied everything, and migrated everything to eu-central-1.

And that’s when things when sideways… The code in us-east-1 is running on node.js 16 and uses "const AWS = require("aws-sdk");"

But the same statement in eu-central-1 keeps giving errors. If I run it in node.js 16 it states this:

errorType": "ReferenceError",
"errorMessage": "require is not defined in ES module scope, you can use import instead",
"stack": [
"ReferenceError: require is not defined in ES module scope, you can use import instead",
at file:///var/task/index.mjs:1:13",
at ModuleJob.run (node:internal/modules/esm/module_job:193:25)",
at async Promise.all (index 0)",
at async ESMLoader.import (node:internal/modules/esm/loader:530:24)",
at async _tryAwaitImport (file:///var/runtime/index.mjs:918:16)",
at async _tryRequire (file:///var/runtime/index.mjs:967:86)",
at async _loadUserApp (file:///var/runtime/index.mjs:991:16)",
at async Object.UserFunction.js.module.exports.load (file:///var/runtime/index.mjs:1032:21)",
at async start (file:///var/runtime/index.mjs:1195:23)",
at async file:///var/runtime/index.mjs:1201:1"

And if I run it in node.js 18 (because I found out that the require statement is something added in this version)

"errorType": "ReferenceError",
"errorMessage": "require is not defined in ES module scope, you can use import instead",
"stack": [
"ReferenceError: require is not defined in ES module scope, you can use import instead",
at file:///var/task/index.mjs:1:13",
at ModuleJob.run (node:internal/modules/esm/module_job:194:25)"`
]

I tried many different syntaxes but none have solved my problem or my knowledge of the problem. When I use the suggested import statement I get errors that the aws-sdk files are not found. But I tried to install them in the same location but that did not work. Probably is this a solution that I should persue but I can’t seem to find any clear information on how to succesfully attach the files (I tried to export the Lambda function and attach the aws-sdk in the folder but that gave the same errors) And more Importantly I want to know why this is occurring, because I definetly didn’t install aws-sdk in the us-east-1 region and there it works, plus the require statement is defined there.

So any reading, tips, suggestion is welcome. I ‘ll keep this update and add the code that you need to provide help (or settings or results of proposed changes).

Here is the working Lambda code (from the us-east-1), the code is the same as in eu-central-1 except for the table name and location.

const AWS = require("aws-sdk");

const dynamo = new AWS.DynamoDB.DocumentClient();



exports.handler = async (event, context) => {
  let body;
  let statusCode = 200;
  const headers = {
    "Content-Type": "application/json"
  };
  
  try {
    switch (event.routeKey) {
      case "DELETE /items/{id}":
        await dynamo
          .delete({
            TableName: "TestID",
            Key: {
              id: event.pathParameters.id
            }
          })
          .promise();
        body = `Deleted item ${event.pathParameters.id}`;
        break;
      case "GET /items/{id}":
        body = await dynamo
          .get({
            TableName: "TestID",
            Key: {
              id: event.pathParameters.id
            }
          })
          .promise();
        break;
      case "GET /items":
        body = await dynamo.scan({ TableName: "TestID" }).promise();
        break;
      case "PUT /items":
        let requestJSON = JSON.parse(event.body);
        if (!requestJSON[0].ModuleID || !requestJSON[0].DataID) {
          throw new Error("Missing required fields: ModuleID or DataID, greetings ");
        }
        await dynamo
          .put({
            TableName: "TestID",
            Item: {
              ModuleID: requestJSON[0].ModuleID,
              DataID: requestJSON[0].DataID,
              TimeStamp: requestJSON[0].TimeStamp,
              ValTemp: requestJSON[0].ValTemp
            }
          })
          .promise();
        body = `Put item ${requestJSON[0].DataID}`;
        break;
      case "PUT /items/batch":
        let requestJSONBatch = JSON.parse(event.body);
        let items = requestJSONBatch.map(item => {
          return {
            PutRequest: {
              Item: {
                ModuleID: item.ModuleID,
                DataID: item.DataID,
                TimeStamp: item.TimeStamp,
                T2: item.T2,
                ValTemp: item.ValTemp
              }
            }
          };
        });
        await dynamo
          .batchWrite({
            RequestItems: {
              "TestID": items
            }
          })
          .promise();
        body = `PUT items`;
        break;
      default:
        throw new Error(`Unsupported route: "${event.routeKey}"`);
    }
  } catch (err) {
    statusCode = 400;
    body = err.message;
  } finally {
    body = JSON.stringify(body);
  }

  return {
    statusCode,
    body,
    headers
  };
};

I followed the suggestion and changed the first line to:

const AWS = require("@aws-sdk/client-s3")

And ran the code in node.js 18 ; I get a similar error:

"errorType": "ReferenceError", "errorMessage": "require is not defined
in ES module scope, you can use import instead", "stack": [
"ReferenceError: require is not defined in ES module scope, you can
use import instead", " at file:///var/task/index.mjs:1:13", " at
ModuleJob.run (node:internal/modules/esm/module_job:194:25)" ]