How to download .xlsx file from AWS MWS API json response? - node.js

Question

I am using the Express JS server to execute AWS MWS API. As per MWS documentation, _GET_REMOTE_FULFILLMENT_ELIGIBILITY_ return excel file object.
I created API in node js but I am not able to get proper excel. I got weird characters in the downloaded excel file.
You can see the downloaded excel file in the attachment.
const getRemoveFulfillmentEligibilityDataCon = async(req,res) => {
const mwsRequestData = {
Version: '2009-01-01',
Action: 'GetReport',
'SellerId': 'MWS_SELLER_ID',
'MWSAuthToken': 'MWS_AUTH_TOKEN',
ReportId: 'XXXXXXXXXXXXXX',
};
try {
const response = await amazonMws.reports.search(mwsRequestData);
/* make the worksheet */
var ws = XLSX.utils.json_to_sheet(response.data);
var wb = XLSX.utils.book_new();
XLSX.utils.book_append_sheet(wb, ws);
XLSX.writeFile(wb, "sheetjs.xlsx");
return response;
} catch (error) {
console.log('error ', error);
return error;
}
}

Answer 1

Finally, I got a solution. I changed my method to call API as below and I got a proper excel file.
I used node-fetch and then send request to Amazon MWS by node-fetch.
node-fetch decode content encoding (gzip/deflate) properly and convert string output to UTF-8 automatically.
var param = {};
param['AWSAccessKeyId'] = 'xxxxxxxxxxxxx';
param['Action'] = 'GetReport';
param['MarketplaceId'] = 'xxxxxxxxxxxxx';
param['SellerId'] = 'xxxxxxxxxxxxx';
param['ReportId'] = 'xxxxxxxxxxxxx';
param['ItemCondition'] = 'New';
param['SignatureMethod'] = 'HmacSHA256';
param['SignatureVersion'] = '2';
param['Timestamp'] = encodeURIComponent(new Date().toISOString());
param['Version'] = '2009-01-01';
secret = 'xxxxxxxxxxxxx';
var url = [];
for(var i in param){
url.push(i+"="+param[i])
}
url.sort();
var arr = url.join("&");
var sign = 'POST\n'+'mws.amazonservices.com\n'+'/Reports/2009-01-01\n'+arr;
const crypto = require('crypto');
let s64 = crypto.createHmac("sha256", secret).update(sign).digest('base64');
let signature = encodeURIComponent(s64);
var bodyData = arr+"&Signature="+signature;
const fileName = "sheetjs.xlsx";
var apiResponse = await fetch('https://mws.amazonservices.com/Reports/2009-01-01', {
method: 'POST',
body: bodyData,
headers: {
'content-type': 'application/x-www-form-urlencoded',
'Accept': '',
},
})
.then(res => {
const dest = fs.createWriteStream('./'+fileName);
res.body.pipe(dest).on('finish', function(){
//console.log('done');
return {'Status': 200, 'Message': 'Downloaded'};
});
})
.catch(error => {
console.log('Request failed', error);
});
return apiResponse;
}