Report is null when trying to get a report that is already in JSON by default

[Philomath88]

First of all, I think the error is with Amazon response for the GET_SALES_AND_TRAFFIC_REPORT (since it says it is plain but it is already in JSON):

headers: {
'x-amz-id-2': 'rlgFAYDwHlr2LGbKaD5I2RJNCe6VWfKVu+75xr4AC/RwWxYrMXQLEMrbkWEiemDF2TuWYhrNkoU=',
'x-amz-request-id': 'CM5WHTZ3B9X2S4EG',
date: 'Sat, 03 Jun 2023 10:29:09 GMT',
'last-modified': 'Sat, 03 Jun 2023 10:28:52 GMT',
'x-amz-expiration': 'expiry-date="Sat, 02 Sep 2023 00:00:00 GMT", rule-id="Rule for: NinetyDays"',
etag: '"50d09cf57b235b1a66159a41f1c0f43c"',
'x-amz-server-side-encryption': 'aws:kms',
'x-amz-server-side-encryption-aws-kms-key-id': 'arn:aws:kms:eu-west-1:538593642818:key/eefdcca3-2e83-416d-b342-a5f2ccdb7ea5',
'x-amz-server-side-encryption-bucket-key-enabled': 'true',
'x-amz-version-id': '3mnV9LmfZEZsg46QKh_KD3cABN7OWa6T',
'accept-ranges': 'bytes',
'content-type': 'text/plain; charset=utf-8',
server: 'AmazonS3',
'content-length': '5825',
connection: 'close'
}
}

This resulted in the report being null (since the CSV library can't parse a JSON). Since I am a newbie programmer (and I have changed other things in the library, am not comfortable with opening up a PR). I have added functionality to try to parse it as JSON and if it is, skip the CSV step. It works now:

async download(details, options = {}){
options = Object.assign({
unzip:true
}, options);
this._validateEncryptionDetails(details);
// Result will be a tab-delimited flat file or an xml document

function isJSONString(str) {
    try {
        JSON.parse(str);
    } catch (e) {
        return false;
    }
    return true;
}


let res = await request({
  url:details.url,
  timeouts:options.timeouts
});
this._validateUpOrDownloadSuccess(res, 'DOWNLOAD');

console.log('res: ', res);

let decrypted_buffer = this._decryptBuffer(details, res.chunks);



// Decompress if content is compressed and unzip option is true
if (details.compressionAlgorithm && options.unzip){
  decrypted_buffer = await this._unzip(decrypted_buffer);
}

console.log("Decrypted Buffer:", decrypted_buffer.toString());
let decrypted = decrypted_buffer;
if (!details.compressionAlgorithm || options.unzip){
  decrypted = this._decodeBuffer(decrypted, res.headers, options.charset);
  if (options.json) {
        try {
            if (isJSONString(decrypted)) {
                // If content is JSON, parse it directly
                decrypted = JSON.parse(decrypted);
            } else if (res.headers['content-type'].includes('xml')) {
                decrypted = this._xml_parser.parse(decrypted);
            } else if (res.headers['content-type'].includes('plain')) {
                decrypted = await csv({
                    delimiter: '\t',
                    quote: 'off',
                }).fromString(decrypted);
                if (options.debug) {
                    console.log("CSV Parsed JSON:", decrypted);
                }
            }
        } catch (e) {
            if (options.debug) {
                console.error("Error while parsing result to JSON:", e);
            }
            throw new CustomError({
                code: 'PARSE_ERROR',
                message: 'Could not parse result to JSON.',
                details: decrypted,
            });
        }
    }
}
if (options.file){
  await this._saveFile(decrypted, options);
}
return decrypted;

}