Async Function working in Express but not NestJs

Question

I initially created a little express server to run a report and file write function.

var ssrs = require('mssql-ssrs');
var fs = require('fs');

const express = require('express')
const app = express()
const port = 3001

app.get('/', (req, res) => {
    reportCreation();
    res.send('File Created');
})

app.get('/api', (req, res) => {
    reportCreation();
    res.json({'File Created': true});
})

app.listen(port, () => {
    console.log(`Report Api listening at http://localhost:${port}`)
})

The function reportCreation() is an async function which gets a report from a SSRS. This works fine

async function reportCreation() {
var serverUrl = 'http://reportServerName/ReportServer/ReportExecution2005.asmx';

ssrs.setServerUrl(serverUrl);

var reportPath = '/ApplicationPortalReports/TestReportNew';
var fileType = 'word';
var parameters = { ApplicationId: 3, TrainingCardId: 267, PortalPersonId: 52 }

var auth = {
    username: 'USERNAME',
    password: 'PASSWORD',
    domain: 'dmz'
};

try {
    var report = await ssrs.reportExecution.getReportByUrl(reportPath, fileType, parameters, auth)
} catch (error) {
    console.log(error);
}
console.log(report);
try {
    fs.writeFile('ReportApiTest.doc', report, (err) => {
        if (!err) console.log('Data written');
    });
} catch (error) {
    console.log(error);

}

I have been working a lot with NestJs recently and wanted to use the same function but within a NestJs service.

@Injectable()
export class AppService {

  async  getReport(): Promise<string> {
   
    const serverUrl = 'http://reportServerName/ReportServer/ReportExecution2005.asmx';

    ssrs.setServerUrl(serverUrl);
    const reportPath = '/ApplicationPortalReports/TestReportNew';
    const fileType = 'word';
    // var parameters = {appId: 3, ReportInstanceId: 1 }
    const parameters = {ApplicationId: 3, TrainingCardId: 267, PortalPersonId: 52 };

    const auth = {
      username: 'USERNAME',
      password: 'PASSWORD',
      domain: 'dmz'
    };

    try {
       var report = await ssrs.reportExecution.getReportByUrl(reportPath, fileType, parameters, auth)
      } catch (error) {
        console.log(error);
      }
      console.log(report);

      // excel = xlsx
      // word = doc
      // pdf = pdf
    try {
      fs.writeFile('ReportApiTest.doc', report,  (err) => {
          if (!err) { console.log('Data written'); 
        return 'File Written Succesfully'}
        });
      } catch (error) {
          console.log(error);
          return 'File Write Error'
      }
      }
  }

As you can see the files are almost identical, but when I run it through NestJs I get an error which looks like a problem with the line

var report = await ssrs.reportExecution.getReportByUrl(reportPath, fileType, parameters, auth)

not awaiting. Why does this work with Express and not NestJS? Below is the error from NestJs

buffer.js:219
  throw new ERR_INVALID_ARG_TYPE(
  ^

TypeError [ERR_INVALID_ARG_TYPE]: The first argument must be one of type string, Buffer, ArrayBuffer,
Array, or Array-like Object. Received type undefined
    at Function.from (buffer.js:219:9)
    at new Buffer (buffer.js:179:17)
    at Object.createType3Message (C:\Projects\SSRS-report-api\ssrs-report-api\node_modules\httpntlm\ntlm.js:172:19)
    at sendType3Message (C:\Projects\SSRS-report-api\ssrs-report-api\node_modules\httpntlm\httpntlm.js:77:23)
    at Immediate._onImmediate (C:\Projects\SSRS-report-api\ssrs-report-api\node_modules\httpntlm\httpntlm.js:101:4)

within the mssql-ssrs node package the getReportByURL looks like this

async function getReportByUrl(reportPath, fileType, params, auth) {
    try {
        var config = {
            binary: true, // very important
            username: auth.userName,
            password: auth.password,
            workstation: auth.workstation,
            domain: auth.domain,
            url: soap.getServerUrl()
                + "?" + (testReportPath(reportPath).replace(/\s/g, '+'))
                + "&rs:Command=Render&rs:Format=" + reportFormat(fileType)
                + formatParamsToUrl(params)
        };
    } catch (err) { report.errorHandler(err) }

    return new Promise((resolve, reject) => {
        config.url = encodeURI(config.url);
        httpntlm.post(config, function (err, res) {
            if (res.statusCode === 500) { reject(res) }
            if (err || res.statusCode !== 200) { reject(err) }
            else { resolve(res.body) }
        })
    })

}

Here is the app.controller.ts

@Controller()
export class AppController {
     constructor(private readonly appService: AppService) {}

  @Get()
  getHello(): Promise<string> {
    return this.appService.getReport();
  }
}

Answer 1

This is not an answer for the question. But after I see your code, I can see an error you will face in future if await ssrs.reportExecution.getReportByUrl(reportPath, fileType, parameters, auth) failed. Actually you see above error because of this.

The way you used the try catch is really bad.

Here's the way I code it.

@Injectable()
export class AppService {

  async  getReport(): Promise<string> {
    const serverUrl = 'http://reportServerName/ReportServer/ReportExecution2005.asmx';

    ssrs.setServerUrl(serverUrl);
    const reportPath = '/ApplicationPortalReports/TestReportNew';
    const fileType = 'word';
    // var parameters = {appId: 3, ReportInstanceId: 1 }
    const parameters = {ApplicationId: 3, TrainingCardId: 267, PortalPersonId: 52 };

    const auth = {
      username: 'USERNAME',
      password: 'PASSWORD',
      domain: 'dmz'
    };

    const report = await ssrs.reportExecution.getReportByUrl(reportPath, fileType, parameters, auth)

    return new Promise(function(resolve, reject) {
        fs.writeFile('ReportApiTest.doc', report, , function(err) {
            if (err) reject(err);
            resolve("File Created");
        });
    });
  }

And in my controller

@POST
async writeFile() {
    try {
        const res = await this.appService.getReport();
        return res;
    } catch(err) {
        // handle your error
    }
}

Answer 2

I had fudged the code in the node_module changing the userName variable to username and had not done the same in the NestJS version. I forgot I had done that so now it is working.