[Kimchi-devel] [PATCH V8 6/7] add method to test libvirt api are available

[Aline Manera]

On 04/24/2014 02:19 PM, shaohef at linux.vnet.ibm.com wrote:
> From: ShaoHe Feng <shaohef at linux.vnet.ibm.com>
>
> same mechanism with other feature tests.
>
> Signed-off-by: ShaoHe Feng <shaohef at linux.vnet.ibm.com>
> Signed-off-by: Royce Lv <lvroyce at linux.vnet.ibm.com>
> ---
>   src/kimchi/config.py.in    | 14 +++++++++++++-
>   src/kimchi/featuretests.py | 42 +++++++++++++++++++++++++++++++++++++++++-
>   2 files changed, 54 insertions(+), 2 deletions(-)
>
> diff --git a/src/kimchi/config.py.in b/src/kimchi/config.py.in

The better place to insert it is in src/kimchi/model/config.py as all 
the feature tests are made there.
So we can have single place for it.

> index f8a645a..bca15ef 100644
> --- a/src/kimchi/config.py.in
> +++ b/src/kimchi/config.py.in
> @@ -26,7 +26,7 @@ import threading
>
>   from ConfigParser import SafeConfigParser
>
> -
> +from kimchi.featuretests import FeatureTests
>   from kimchi.xmlutils import xpath_get_text
>
>   __version__ = "@kimchiversion@"
> @@ -125,6 +125,18 @@ class Paths(object):
>   paths = Paths()
>
>
> +class LivirtSupportAPI(object):
> +    def __init__(self):
> +        self.apis = {
> +            "meta_element": FeatureTests.libvirt_config_support_metadata()}
> +
> +    def get_apis(self):
> +        return self.apis
> +
> +
> +libvirt_support_apis = LivirtSupportAPI().get_apis()
> +
> +
>   class PluginPaths(Paths):
>
>       def __init__(self, name):
> diff --git a/src/kimchi/featuretests.py b/src/kimchi/featuretests.py
> index b1001ea..956f328 100644
> --- a/src/kimchi/featuretests.py
> +++ b/src/kimchi/featuretests.py
> @@ -23,14 +23,15 @@ import lxml.etree as ET
>   import socket
>   import subprocess
>   import threading
> +import uuid
>
>
>   from lxml.builder import E
>
>
> +from kimchi.rollbackcontext import RollbackContext
>   from kimchi.utils import kimchi_log
>
> -
>   ISO_STREAM_XML = """
>   <domain type='kvm'>
>     <name>ISO_STREAMING</name>
> @@ -53,6 +54,17 @@ ISO_STREAM_XML = """
>     </devices>
>   </domain>"""
>
> +SIMPLE_VM_XML = """
> +<domain type='kvm'>
> +  <name>%s</name>

> +  <uuid>%s</uuid>

the uuid is not required to create a vm

> +  <memory unit='KiB'>10240</memory>
> +  <os>
> +    <type arch='x86_64' machine='pc'>hvm</type>
> +    <boot dev='hd'/>
> +  </os>
> +</domain>"""
> +
>   SCSI_FC_XML = """
>   <pool type='scsi'>
>     <name>TEST_SCSI_FC_POOL</name>
> @@ -175,3 +187,31 @@ class FeatureTests(object):
>               pool is None or pool.undefine()
>               conn is None or conn.close()
>           return True
> +
> +    @staticmethod
> +    def libvirt_config_support_metadata():
> +        vm_uuid = uuid.uuid1()
> +        vm_name = "kimchi_test_%s" % vm_uuid
> +        KIMCHI_META_URL = "https://github.com/kimchi-project/kimchi/metadata/"
> +        xml = SIMPLE_VM_XML % (vm_name, vm_uuid)
> +        meta_support = False
> +        with RollbackContext() as rollback:
> +            FeatureTests.disable_screen_error_logging()
> +            rollback.prependDefer(FeatureTests.enable_screen_error_logging)
> +            conn = libvirt.open('qemu:///system')
> +            rollback.prependDefer(conn.close)
> +            dom = conn.defineXML(xml)
> +            rollback.prependDefer(dom.undefine)
> +            try:
> +                dom.setMetadata(libvirt.VIR_DOMAIN_METADATA_ELEMENT,
> +                                "<metatest/>", "kimchi",
> +                                KIMCHI_META_URL + "metatest",
> +                                flags=libvirt.VIR_DOMAIN_AFFECT_CURRENT)
> +                meta_support = True
> +            except libvirt.libvirtError as e:
> +                if e.get_error_code() == libvirt.VIR_ERR_ARGUMENT_UNSUPPORTED:
> +                    meta_support = False
> +                else:
> +                    raise

You should not raise an exception during feature test.
Independent of which error occurred you should only return meta_support 
= False and handle that info when using it

except libvirt.libvirtError as e:
     return False

> +
> +        return meta_support