request = require('request');
const fs = require('fs');

const appID = '<APP_ID>';
const reportType = '<REPORT_TYPE>';
const from = '<FROM_DATA>';
const to = '<T0_DATE>';
const requestUrl = `https://hq.appsflyer.com/export/${appID}/${reportType}/v5?api_token=${apiToken}&from=${from}&to=${to}`;

request(requestUrl, (error, response, body) => {
  if (error) {
    console.log('There was a problem retrieving data:', error);
  }
  else if (response.statusCode != 200) {
    if (response.statusCode === 404) {
      console.log('There is a problem with the request URL. Make sure that it is correct');
    } else {
      console.log('There was a problem retrieving data:', response.body);
    }
  } else {
    fs.writeFile(`${appID}-${reportType}-${from}-to-${to}.csv`,response.body,(err) => {
      if (err) {
        console.log('There was a problem writing to file: ', err);
      } else {
        console.log('File was saved');
      }
    });
  }
  
});

import requests

app_id = '<APP_ID>'
report_type = '<REPORT_TYPE>'

params = {
  'from': 'FROM_DATE',
  'to': 'TO_DATE'
}

request_url = 'https://hq.appsflyer.com/export/{}/{}/v5'.format(app_id, report_type)

res = requests.request('GET', request_url, params=params)

if res.status_code != 200:
  if res.status_code == 404:
    print('There is a problem with the request URL. Make sure that it is correct')
  else:
    print('There was a problem retrieving data: ', res.text)
else:
  f = open('{}-{}-{}-to-{}.csv'.format(app_id, report_type, params['from'], params['to']), 'w', newline='', encoding="utf-8")
  f.write(res.text)
  f.close()

using System;
using RestSharp;
using System.Text;
using System.Net;
using System.IO;
namespace Pull_API
{
  class PullAPi
  {
    static void Main(string[] args)
    {
      var appID = "<APP_ID>";
      var reportType = "<REPORT_TYPE>";
      var from = "<FROM_DATE>";
      var to = "<TO_DATE>";

      var requestUrl = "https://hq.appsflyer.com/export/"+ appID + "/" + reportType + "/v5?api_token="+ apiToken + "&from=" + from + "&to=" + to;
      
      var client = new RestClient(requestUrl);
      var request = new RestRequest(Method.GET);
      request.AddHeader("Accept", "text/csv; charset=UTF-8");

      IRestResponse response = client.Execute(request);
      HttpStatusCode statusCode = response.StatusCode;
      int numericStatusCode = (int)statusCode;

      if(numericStatusCode != 200){

        if(numericStatusCode == 404){
          Console.WriteLine("There is a problem with the request URL. Make sure that it is correct.");
        } else {
          Console.WriteLine("There was a problem retrieving data: " + response.Content); 
        }
      } else {
        System.IO.File.WriteAllText(@"" + appID + "-" + reportType + "-" + from + "-to-" + to + ".csv", response.Content);
        Console.WriteLine("Data retrieved succesfully"); 
      }
    }
  }
}

<?

$appID = '<APP_ID>';
$reportType = '<REPORT_TYPE>';
$from = '<FROM_DATE>';
$to = '<TO_DATE>';
$query = http_build_query([
'from' => $from,
'to' => $to
]);
$requestUrl = 'https://hq.appsflyer.com/export/' .$appID .'/' .$reportType .'/v5?'.$query;
$report = $appID .'-' .$report .'-' .$from .'-to-' .$to; 

$curl = curl_init($requestUrl);
curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
curl_setopt($curl, CURLOPT_ENCODING, "");
curl_setopt($curl, CURLOPT_NOSIGNAL, true);
curl_setopt($curl, CURLOPT_FOLLOWLOCATION, true);
curl_setopt($curl, CURLOPT_MAXREDIRS, 10);
curl_setopt($curl, CURLOPT_FAILONERROR, true);
curl_setopt($curl, CURLOPT_TIMEOUT, 100);
curl_setopt($curl, CURLOPT_CUSTOMREQUEST, "GET");
curl_setopt($curl, CURLOPT_HTTPHEADER, array(
 "cache-control: no-cache",
 "Accept: text/csv; charset=UTF-8"
));


$response = curl_exec($curl);
$info = curl_getinfo($curl);
$err = curl_error($curl);
curl_close($curl);

var_dump($response);
if ($err) {
 echo $info['http_code']; 
 echo "cURL Error #: " .$err .'. ';
 if ($info['http_code'] == 404) {
  echo 'There is a problem with the request URL. Make sure that it is correct';
 } 
 if ($info['http_code'] == 401) {
  echo 'There was a problem retrieving data: authentication failed.';
 }
 
 echo PHP_EOL;

} else {
 $fp = fopen($report, 'w+');
 fwrite($fp, $response);
 fclose($fp);
 echo $response;
}
?>