final code

.env

@@ -1,3 +1,3 @@
-PORT=3001
+PORT=4000
 MONGODB_LOCAL_URL=mongodb://localhost:27017/graphql-upload
 BASE_URL = http://localhost:

Middlewares/file.js

@@ -1,20 +1,20 @@
-const {parse, join} = require("path"); // This is node built in package
-const {createWriteStream} = require("fs"); // this is node built in package
-const fs = require("fs"); // this is node built in package
+const {parse, join} = require("path"); 
+const {createWriteStream} = require("fs"); 
+const fs = require("fs"); 
 
 module.exports.readFile = async (file) => {
     const {createReadStream, filename} = await file;
     const stream = createReadStream();
-    var {ext, name} = parse(filename);
+    var {ext, name} = parse(filename); // extension and name separate
     name = `single${Math.floor((Math.random() * 10000) + 1)}`;
-    let url = join(__dirname, `../Upload/${name}-${Date.now()}${ext}`);
+    let url = join(__dirname, `../Upload/${name}-${Date.now()}${ext}`); // directory url
     const imageStream = await createWriteStream(url)
     await stream.pipe(imageStream);
     const baseUrl = process.env.BASE_URL
     const port = process.env.PORT
-    url = `${baseUrl}${port}${url.split('Upload')[1]}`;
+    url = `${baseUrl}${port}${url.split('Upload')[1]}`; // server url
     return url;
-} // This is single readfile
+} 
 
 module.exports.multipleReadFile = async (file) => {
     let fileUrl = [];
@@ -32,4 +32,11 @@ module.exports.multipleReadFile = async (file) => {
         fileUrl.push({url});
     }
     return fileUrl
-}
+}
+// Quey for image upload in Altair
+// mutation singleUpload($file:Upload!){
+//     singleUpload(file:$file){
+//       message
+//     }
+
+//   }

Resolvers/uploadResolver.js

@@ -11,7 +11,7 @@ module.exports = {
     Mutation: {
         singleUpload: async (_, {file}) => {
             const imageUrl = await readFile(file);
-            const singlefile = new SingleFile({image: imageUrl});
+            const singlefile = new SingleFile({image: imageUrl}); // saving image url in db
             await singlefile.save();
             return {
                 message: "Single file uploaded successfully!"
@@ -27,7 +27,4 @@ module.exports = {
             }
         }
     }
-} // That's it, Let's check it.
-//Let's check it
-
-// Let's create function for multiple File Upload
+} 

app.js

@@ -2,6 +2,7 @@ const express = require("express");
 const cors = require("cors");
 
 const app = express();
+app.use(express.static('./Upload')) // fo image access using url
 
 app.use(express.json());
 app.use(cors());