On 01/23/2014 08:16 AM, apporc wrote:

When running feature tests, we get bunch of error messages as below:

*** Running feature tests ***
libvirt: Domain Config error : internal error unknown protocol type 'http'
libvirt: Domain Config error : internal error unknown protocol type 'https'
libvirt: Domain Config error : internal error unknown protocol type 'ftp'
libvirt: Domain Config error : internal error unknown protocol type 'ftps'
libvirt: Domain Config error : internal error unknown protocol type 'tftp'
*** Feature tests completed ***

By replacing default error handler of libvirt, this patch succeeded to
avoid the error. After Featuretest, the default error handler will be restored.
The default error handler(in libvirtmod.so) just do one thing, it prints the error message to
stderr before we catch the exception in python.

Signed-off-by: apporc <appleorchard2000@gmail.com>
---
  src/kimchi/featuretests.py |   14 ++++++++++++--
  1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/src/kimchi/featuretests.py b/src/kimchi/featuretests.py
index a5755a2..d68fcb8 100644
--- a/src/kimchi/featuretests.py
+++ b/src/kimchi/featuretests.py
@@ -57,16 +57,26 @@ class FeatureTests(object):

      @staticmethod
      def libvirt_supports_iso_stream(protocol):
+        def libvirt_errorhandler(userdata, error):
+            # A libvirt error handler to ignore annoying messages in stderr
+            pass
+
          xml = ISO_STREAM_XML % {'protocol': protocol}
          conn = None
          try:
+            # Register the error handler to hide libvirt error in stderr
+            libvirt.registerErrorHandler(f=libvirt_errorhandler, ctx=None)
              conn = libvirt.open('qemu:///system')
              dom = conn.defineXML(xml)
              dom.undefine()
              return True
-        except libvirt.libvirtError:
-            return False

+        except libvirt.libvirtError, e:
+            if e.message == "internal error unknown protocol type '%s'" % protocol:
+                return False
+            else:
+                raise e

Independent of the exception we should not raise it.
It is a feature test, so if something failed we just return 'False' and backend will handle it correctly.

          finally:
+            libvirt.registerErrorHandler(f=None, ctx=None)
              conn is None or conn.close()

      @staticmethod