fix(upload): add gm image identification

Fixes #96

lib/compute/image-cc.js

@@ -23,15 +23,23 @@ function processImage(src, width, height) {
     // The '>' modifier does this.
     // See more: http://www.graphicsmagick.org/GraphicsMagick.html
     limit(gm(src)
-      .resize(width, height, '>'))
-      .noProfile()
-      .toBuffer('png', function(err, buf) {
+      .identify(function (err) {
         if (err) {
-          reject(err);
-        } else {
-          resolve(buf);
+          // if gm cannot identify this image, then reject
+          return reject (err);
         }
-      });
+
+        limit(gm(src).resize(width, height, '>')
+          .noProfile()
+          .toBuffer('png', function(err, buf) {
+            if (err) {
+              reject(err);
+            } else {
+              resolve(buf);
+            }
+          }));
+      })
+    );
   });
 }
 

lib/img-workers.js

@@ -30,13 +30,17 @@ exports.upload = function upload(id, payload, headers) {
     };
     logger.verbose('upload', url);
     payload.pipe(request.post(url, opts, function(err, res, body) {
+      var nestedError = null;
+      if (body && body[0] && body[0].error) {
+        nestedError = body[0].error;
+      }
       if (err) {
         logger.error('upload.network.error', err);
         reject(AppError.processingError(err));
         return;
       }
 
-      if (res.statusCode >= 400 || body.error) {
+      if (res.statusCode >= 400 || body.error || nestedError) {
         logger.error('upload.worker.error', body);
         reject(AppError.processingError(body));
         return;

test/api.js

@@ -480,6 +480,40 @@ describe('/avatar', function() {
       });
     });
 
+    it('should fail with an error if image cannot be identified', function() {
+      this.slow(2000);
+      this.timeout(3000);
+
+      var dataLength = 2;
+      mock.token({
+        user: USERID,
+        email: 'user@example.domain',
+        scope: ['profile:avatar:write']
+      });
+      mock.log('img_workers', function(rec) {
+        if (rec.levelname === 'ERROR') {
+          return true;
+        }
+      });
+      mock.log('server', function(rec) {
+        if (rec.levelname === 'ERROR') {
+          return true;
+        }
+      });
+
+      return Server.api.post({
+        url: '/avatar/upload',
+        payload: Buffer('{}'),
+        headers: { authorization: 'Bearer ' + tok,
+          'content-type': 'image/png',
+          'content-length': dataLength
+        }
+      }).then(function(res) {
+        assert.equal(res.statusCode, 500);
+        assert.equal(res.result.message, 'Image processing error');
+      });
+    });
+
     it('should gracefully handle and report upload failures', function() {
       mock.token({
         user: USERID,