From 99970410933700062743a172b7616310db5e21bc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Miroslav=20Bajto=C5=A1?= <mbajtos@cz.ibm.com>
Date: Thu, 10 Nov 2016 14:20:38 +0100
Subject: [PATCH] Clean up "download()" implementation

Reduce nesting, remove repetition.
---
 lib/storage-handler.js | 94 +++++++++++++++++++++---------------------
 1 file changed, 47 insertions(+), 47 deletions(-)

diff --git a/lib/storage-handler.js b/lib/storage-handler.js
index 4063bf6..96080ea 100644
--- a/lib/storage-handler.js
+++ b/lib/storage-handler.js
@@ -233,57 +233,57 @@ exports.download = function(provider, req, res, container, file, cb) {
 
   var range = null;
 
-  if (req) {
-    if (req.headers) {
-      range = req.headers.range || '';
+  if (!req) {
+    // TODO(rfeng/bajtos) We should let the caller now about the problem!
+    return;
+  }
+
+  if (req.headers) {
+    range = req.headers.range || '';
+  }
+
+  if (!range) {
+    return download(params);
+  }
+
+  provider.getFile(params.container, params.remote, function(err, stats) {
+    if (err) {
+      return handleError(res, err);
     }
 
-    if (range) {
-      provider.getFile(params.container, params.remote, function(err, stats) {
-        if (err) {
-          handleError(res, err);
-        } else {
-          var total = stats.size;
+    setupPartialDownload(params, stats, res);
+    download(params);
+  });
 
-          var parts = range.replace(/bytes=/, '').split('-');
-          var partialstart = parts[0];
-          var partialend = parts[1];
+  function download(params) {
+    var reader = provider.download(params);
 
-          params.start = parseInt(partialstart, 10);
-          params.end = partialend ? parseInt(partialend, 10) : total - 1;
+    res.type(fileName);
 
-          var chunksize = (params.end - params.start) + 1;
-
-          res.status(206);
-          res.set('Content-Range', 'bytes ' + params.start + '-' + params.end + '/' + total);
-          res.set('Accept-Ranges', 'bytes');
-          res.set('Content-Length', chunksize);
-
-          var reader = provider.download(params);
-
-          res.type(fileName);
-
-          reader.pipe(res);
-          reader.on('error', function(err) {
-            handleError(res, err);
-          });
-          reader.on('end', function() {
-            cb();
-          });
-        }
-      });
-    } else {
-      var reader = provider.download(params);
-
-      res.type(fileName);
-
-      reader.pipe(res);
-      reader.on('error', function(err) {
-        handleError(res, err);
-      });
-      reader.on('end', function() {
-        cb();
-      });
-    }
+    reader.pipe(res);
+    reader.on('error', function onReaderError(err) {
+      handleError(res, err);
+    });
+    reader.on('end', function onReaderEnd() {
+      cb();
+    });
   }
 };
+
+function setupPartialDownload(params, stats, res) {
+  var total = stats.size;
+
+  var parts = range.replace(/bytes=/, '').split('-');
+  var partialstart = parts[0];
+  var partialend = parts[1];
+
+  params.start = parseInt(partialstart, 10);
+  params.end = partialend ? parseInt(partialend, 10) : total - 1;
+
+  var chunksize = (params.end - params.start) + 1;
+
+  res.status(206);
+  res.set('Content-Range', 'bytes ' + params.start + '-' + params.end + '/' + total);
+  res.set('Accept-Ranges', 'bytes');
+  res.set('Content-Length', chunksize);
+};