Implement image resizing

src/controllers/uploads.controller.js

@@ -1,12 +1,6 @@
 import mkdirp from 'mkdirp';
+import { resize } from '../../src/utils/imageResizer';
 
-const classifyFile = (file) => {
-  console.log(`File mimetype: ${file.mimetype}`);
-  if (file.mimetype.split('/')[0] === 'image') {
-    // TODO: Perform image specific operations
-    console.log('File classified as an image.');
-  }
-};
 
 function upload(req, res, next, config) {
     if (Object.keys(req.files).length === 0) {
@@ -20,10 +14,13 @@ function upload(req, res, next, config) {
       }
     });
 
-    req.files.file.mv(`${config.staticDir}/${req.files.file.name}`, (err) => {
+    let outputFilepath = `${config.staticDir}/${req.files.file.name}`;
+    req.files.file.mv(outputFilepath, (err) => {
       if (err) return res.status(500).send(err);
 
-      classifyFile(req.files.file);
+      if (req.files.file.mimetype.split('/')[0] === 'image') {
+        resize(config, req.files.file);
+      }
       res.send('File uploaded.');
     })
 }

src/utils/imageResizer.js

@@ -0,0 +1,31 @@
+import sharp from 'sharp';
+import sizeOf from 'image-size';
+
+function getOutputImageName(sourceImage, size) {
+  let extension = sourceImage.split('.').pop();
+  let filenameWithoutExtension = sourceImage.substr(0, sourceImage.lastIndexOf('.')) || sourceImage;
+  return `${filenameWithoutExtension}-${size.name}.${extension}`;
+}
+
+export function resize(config, file) {
+  let sourceImage = `${config.staticDir}/${file.name}`;
+
+  sizeOf(sourceImage, (err, dimensions) => {
+    for (let size of config.imageSizes) {
+      if (size.width > dimensions.width) {
+        console.log(`${size.width} is greater than actual width ${dimensions.width}`);
+        continue;
+      }
+      let outputImage = getOutputImageName(sourceImage, size);
+      sharp(sourceImage)
+        .resize(size.width, size.height, {
+          position: size.crop || 'centre'
+        })
+        .toFile(outputImage, (err) => {
+          if (err) console.log('Error writing resized file', err);
+          console.log(`Resized image from ${dimensions.width}x${dimensions.height} to ${size.width}x${size.height}`);
+        });
+
+    }
+  });
+}