Uploading and downloading image or pdf file from node js to mysql database and than sending this image or pdf file to client side

See more:

Javascript

Node.js

Express

I am building an application where my client required to upload some images and download them back when required I am using Mysql Database for rest application so I have decided to save all images as Blob file in my database in this I need to accomplish below task

1.upload image file from client side to node js express server using XMLHttpRequest
2.save image as blob file from node js express backend to Mysql Databse
3.retrive Image back when required from Mysql Databse using node js express backend and send image file to client
4.display/Download Image received from backend

from this above 4 tasks I was able to complete 3 but at unable to complete last one details of code is as per below

please advice how to convert blob file back to Image and display or download same at client side

What I have tried:

1.upload image file from client side to node js express server using XMLHttpRequest

var file=document.getElementById("uploadedfile").files[0];
    let formData=new FormData();
    formData.append("file",file);    
    var xhttp=new XMLHttpRequest();
    xhttp.onreadystatechange=function(){}
    xhttp.open("POST","/formula144",true);    
    xhttp.send(formData);

2.save image as blob file from node js express backend to Mysql Databse

if(!req.files){
            console.log("No Files Found");
        }else{
            let imagedata=req.files.file;
            console.log(imagedata);
            let sql="UPDATE form92 SET form92.rc_photo=? WHERE form92.trucknoform11='RJ-52GA-1362'";
            let query=conn.query(sql,[imagedata.data],(err,results)=>{
                if(err){
                    console.log(err);
                }
            });            
        }

3.retrive Image back when required from Mysql Databse using node js express backend and send image file to client

sql3="SELECT form92.rc_photo FROM form92 WHERE form92.trucknoform11='"+req.query.truck_no+"'";
                   let query3=conn.query(sql3,(err,results3)=>{
                       if(err){
                           console.log(err);
                       }else{
                           res.send(results3[0].rc_photo);
                       }
                   });

4.display/Download Image received from backend

xhttp=new XMLHttpRequest();
  xhttp.onreadystatechange=function(){
      if(this.readyState==4&&this.status==200){
          var myblobObj=this.response;
          var encodedUri=encodeURI(myblobObj);
          var link=document.createElement('a');
          link.setAttribute("href",encodedUri);
          link.setAttribute("download","file.jpg");
          document.body.appendChild(link);
          link.click();
      }
  }
  xhttp.open("GET","/formula143a?"+fdata,true);
  xhttp.setRequestHeader('Content-Type','application/X-www-form-urlencoded');
  xhttp.send();