[Kimchi-devel] [PATCH V7 5/5] manually manage the metadata element

[Aline Manera]

On 04/24/2014 02:31 AM, shaohef at linux.vnet.ibm.com wrote:
> From: ShaoHe Feng <shaohef at linux.vnet.ibm.com>
>
> virDomain.metadata and virDomain.setMetadata does not work in all livirt
> versions used in the supported distros.
>
> So if libvirt do not support these two API.
>
> let kimchi manually manage the metadata element
>
> Signed-off-by: ShaoHe Feng <shaohef at linux.vnet.ibm.com>
> Signed-off-by: Royce Lv <lvroyce at linux.vnet.ibm.com>
> ---
>   src/kimchi/model/utils.py | 38 +++++++++++++++++++++++++++++++++++---
>   1 file changed, 35 insertions(+), 3 deletions(-)
>
> diff --git a/src/kimchi/model/utils.py b/src/kimchi/model/utils.py
> index be5e526..55cf5ca 100644
> --- a/src/kimchi/model/utils.py
> +++ b/src/kimchi/model/utils.py
> @@ -20,6 +20,7 @@
>   from kimchi.exception import OperationFailed
>   import libvirt
>   from lxml import etree
> +from lxml.builder import E
>
>
>   KIMCHI_META_URL = "https://github.com/kimchi-project/kimchi/metadata/"
> @@ -53,9 +54,30 @@ def set_vm_metadata_element(dom, meta_xml, mode="all"):
>       # From libvirt doc, Passing None for @metadata says to remove that element
>       # from the domain XML (passing the empty string leaves the element present)
>       # Do not support remove the old metadata
> -    dom.setMetadata(libvirt.VIR_DOMAIN_METADATA_ELEMENT, meta_xml,
> -                    "kimchi", KIMCHI_META_URL + element.tag,
> -                    flags=get_vm_config_flag(dom, mode))
> +    try:
> +        dom.setMetadata(libvirt.VIR_DOMAIN_METADATA_ELEMENT, meta_xml,
> +                        "kimchi", KIMCHI_META_URL + element.tag,
> +                        flags=get_vm_config_flag(dom, mode))
> +    except libvirt.libvirtError as e:
> +        # FIXME remove this code when all distro libvirt supports setMetadata
> +        if e.get_error_code() == libvirt.VIR_ERR_ARGUMENT_UNSUPPORTED:
> +            # some other tools will not let libvirt create a persistent
> +            # configuration, raise exception.
> +            if not dom.isPersistent():
> +                msg = 'The VM has not a persistent configuration'
> +                raise OperationFailed("KCHVM0030E",
> +                                      {'name': dom.name(), "err": msg})
> +            xml = dom.XMLDesc(libvirt.VIR_DOMAIN_XML_INACTIVE)
> +            root = etree.fromstring(xml)
> +            metadata = root.find("metadata")
> +            if metadata is None:
> +                metadata = E.metadata()
> +                root.append(metadata)
> +            old_elem = metadata.find(element.tag)
> +            (metadata.replace(old_elem, element) if old_elem is not None
> +             else metadata.append(element))
> +
> +            dom.connect().defineXML(etree.tostring(root))
>
>
>   def get_vm_metadata_element(dom, element, mode="current"):
> @@ -64,6 +86,16 @@ def get_vm_metadata_element(dom, element, mode="current"):
>                               KIMCHI_META_URL + element,
>                               flags=get_vm_config_flag(dom, mode))
>       except libvirt.libvirtError as e:
> +        # FIXME remove this code when all distro libvirt supports metadata
> +        if e.get_error_code() == libvirt.VIR_ERR_ARGUMENT_UNSUPPORTED:

if e.get_error_code() in [libvirt.VIR_ERR_ARGUMENT_UNSUPPORTED, 
libvirt.VIR_ERR_NO_SUPPORT]:

> +            # some other tools will not let libvirt create a persistent
> +            # configuration, just return empty
> +            if not dom.isPersistent():
> +                return ""
> +            xml = dom.XMLDesc(libvirt.VIR_DOMAIN_XML_INACTIVE)
> +            root = etree.fromstring(xml)
> +            elements = root.xpath("metadata/%s" % element)
> +            return etree.tostring(elements[0]) if elements else ""
>           if e.get_error_code() == libvirt.VIR_ERR_NO_DOMAIN_METADATA:
>               return ""
>           else: