working URL uploader

code/utils/utils.py

@@ -1,23 +1,24 @@
 import os
 from datetime import datetime
 from flask import current_app as app
+import requests
+import re
 try:
     from urllib.request import pathname2url
-    from urllib.request import URLopener
     from urllib.request import urlparse
-    from urllib.error import HTTPError
 except ImportError:
     from urllib import pathname2url
-    from urllib import URLopener
     from urlparse import urlparse
-    from urllib2 import HTTPError
 
 
-def download_url(url,filename):
-    downloader = URLopener()
+def download_url(url, filename):
     try:
-        downloader.retrieve(url, filename)
-    except HTTPError as e:
+        r = requests.get(url, stream=True)
+        with open(filename, 'wb') as f:
+            for chunk in r.iter_content(chunk_size=1024 * 1024):
+                if chunk: # filter out keep-alive new chunks
+                    f.write(chunk)
+    except requests.exceptions.RequestException as e:
         return (False, ("%s %s"%(e.code,e.reason), e.code))
     return (True, ("OK", 200 ))
 
@@ -144,6 +145,9 @@ def safe_path(s):
     return safe_string(s, "-_/")
 
 
-def safe_string(s, valid):
+def safe_string(s, valid, no_repeat = False):
     """ return a safe string, replace non alnum characters with _ . all characters in valid are considered valid. """
-    return "".join([c if c.isalnum() or c in valid else "_" for c in s])
+    safe = "".join([c if c.isalnum() or c in valid else "_" for c in s])
+    if no_repeat:
+        safe = re.sub(r'_+', '_', safe)
+    return safe