Merge branch 'sam/fix-tarball-failure'

Reviewed-By: Adam Coldrick <adam.coldrick@codethink.co.uk>
Reviewed-By: Francisco Redondo Marchena <francisco.marchena@codethink.co.uk>

1 files changed, 16 insertions, 5 deletions

diff --git a/lorry b/lorry
index 127a1fb..d28d064 100755
--- a/lorry
+++ b/lorry
@@ -30,6 +30,12 @@ __version__ = '0.0'
 
 lorry_path = os.path.realpath(__file__)
 
+
+def file_missing_or_empty(filename):
+    ''' A more comprehensive alternative to os.path.exists(). '''
+    return (not os.path.isfile(filename)) or (os.path.getsize(filename) <= 0)
+
+
 def quote_url(url):
     ''' Convert URIs to strings that only contain digits, letters, % and _.
 
@@ -475,12 +481,17 @@ class Lorry(cliapp.Application):
         basename = os.path.basename(url_path)
         tardest = os.path.join(dirname, basename)
         self.progress('.. checking if we need to fetch %s' % basename)
-        if not os.path.exists(tardest):
+        if file_missing_or_empty(tardest):
             self.progress('.. attempting to fetch.')
-            with open(tardest, 'w') as tarfile:
-                urlfile = urllib2.urlopen(spec['url'])
-                tarfile.write(urlfile.read())
-                urlfile.close()
+            try:
+                with open(tardest, 'w') as tarfile:
+                    urlfile = urllib2.urlopen(spec['url'])
+                    tarfile.write(urlfile.read())
+                    urlfile.close()
+            except Exception as e:
+                if os.path.exists(tardest):
+                    os.unlink(tardest)
+                raise
         else:
             self.progress('.. no need to run, nothing to do')
             return