deleteFriendByValue.js

async function deleteFriendByValue(friendName: string) {
  const Key = { id: "1234" };
  // Delete the value from the set. This operation is idempotent and will not
  // produce an error if the value(s) are missing.
  const { err, data } = await updateWithErrorWrapper({
    TableName,
    Key,
    UpdateExpression: `DELETE friends :valuesToRemove`,
    ExpressionAttributeValues: {
      ":valuesToRemove": DynamoDB.createSet([friendName])
    }
  });

  if (err) {
    console.error("unhandled error: " + err);
    return false;
  }

  return true;
}