Progress Bar for download_url (#497)

* Added Progress Bar to the dataset downloading utility

* Updated progressbar to update by blcoks

* Added progressbar2 to the requirements

* fixed style issues

* Shifted from progressbar to tqdm

setup.py

@@ -33,6 +33,7 @@ def find_version(*file_paths):
     'pillow >= 4.1.1',
     'six',
     'torch',
+    'tqdm'
 ]
 
 setup(

torchvision/datasets/utils.py

@@ -2,6 +2,15 @@
 import os.path
 import hashlib
 import errno
+from tqdm import tqdm
+
+
+def gen_bar_updator(pbar):
+    def bar_update(count, block_size, total_size):
+        pbar.total = total_size / block_size
+        pbar.update(count)
+
+    return bar_update
 
 
 def check_integrity(fpath, md5):
@@ -38,7 +47,7 @@ def download_url(url, root, filename, md5):
     else:
         try:
             print('Downloading ' + url + ' to ' + fpath)
-            urllib.request.urlretrieve(url, fpath)
+            urllib.request.urlretrieve(url, fpath, reporthook=gen_bar_updator(tqdm()))
         except:
             if url[:5] == 'https':
                 url = url.replace('https:', 'http:')