Error: could not unmarshal the value dynamodb

Answered by Rafal Wilinski
What's Causing This Error
The DynamoDB unmarshal function can only accept an object (with data the structure of DynamoDB). Therefore, if you try to pass an array of these objects into the unmarshal function, it will throw an error.
Solution: Here's How To Resolve It
To resolve the error, iterate through the array of DynamoDB objects and "unmarshall" each object individually, as shown below.
const items = [
  { 
      uId: { S: '123456789' }, 
      date: { S: '09-06-2022' } 
  }
];
  
const unmarshalled = items.map((i) => aws.dynamodb.converter.unmarshall(i));
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