Implement basic testing.

setup.py

@@ -30,4 +30,5 @@ setup(
     zip_safe=True,
     packages=find_packages(),
     namespace_packages=['slapos'],
+    test_suite="slapos.libnetworkcachetests"
     )

slapos/libnetworkcachetests.py

+import unittest
+from slapos.libnetworkcache import NetworkcacheClient
+import tempfile
+
+class OfflineTest(unittest.TestCase):
+  def test_download_offline(self):
+    nc = NetworkcacheClient('http://127.0.0.1:0', 'http://127.0.0.1:0')
+    self.assertRaises(IOError, nc.download, 'sha512sum')
+
+  def test_upload_offline(self):
+    content = tempfile.TemporaryFile()
+    nc = NetworkcacheClient('http://127.0.0.1:0', 'http://127.0.0.1:0')
+    self.assertRaises(IOError, nc.upload, content)