title: no such file or directory when downloading a file from firebase cloud storage using http cloud cloud functions
body: <p>I wrote a .txt file in firebase cloud storage and i want to download that .txt file and sending it to another server validation. I tried so many ways to download that file but i am getting an error like </p>
  
  <pre><code>"Error: ENOENT: no such file or directory, open '/Users/vijayasrivuddanti/Downloads/download.txt'
      at Error (native)
    errno: -2,
    code: 'ENOENT',
    syscall: 'open',
    path: '/Users/vijayasrivuddanti/Downloads/download.txt'"
  </code></pre>
  
  <p>This is the code i tried :</p>
  
  <pre><code>function writetofile(){
  const storage = new Storage();
  const  bucket = storage.bucket('deyapay-192704.appspot.com'); 
  console.log("date",Date.now());
  var datetime = new Date();
  console.log("iso", new Date().toISOString().slice(0,10));
  const file = bucket.file(new Date().toISOString().slice(0,10)+".txt"); // It create the file in the bucket in ascii format and save as today date format.
  const a = new Date().toISOString().slice(0,10)+".ascii"
  console.log("filename",a);
  var storageRef = admin.storage().bucket();
  const uploadStream = file.createWriteStream();
  uploadStream.on('error', function(err) {
  console.log("write err",err);
  });
  finalnachaformat.forEach(function(v) { // It takes the each value in 
                                         finalnachaformat in every loop.
      console.log("v",v)
      console.log("gii");
      uploadStream.write(v+ '\n'); // and write data into file.
      console.log("looping function",v);   
  }) 
   console.log("successfully uploaded")
  uploadStream.end();// writing end
  //-
  // Download a file into memory. The contents will be available as the second
  // argument in the demonstration below, `contents`.
  //-
  file.download(function(err, contents) {});
  
  //-
  // Download a file to a local destination.
  //-
  file.download({
    destination: '/Users/vijayasrivuddanti/Downloads/download.txt'
  
  }, function(err) {
  
      console.log("error",err);
  });
  
  //-
  // If the callback is omitted, we'll return a Promise.
  //-
  file.download().then(function(data) {
    const contents = data[0];
    console.log("entred");
    res.send("ok");
  });
  </code></pre>
  
  <p>How to solve that error? Is there any way for downloading that file from cloud storage and how to get the stored file URL as response from cloud functions.</p>