[libvirt] [PATCH] network: Added hook for network modification event

[Cole Robinson]

On 07/26/2016 11:50 AM, Laine Stump wrote:
> Sorry, I was offline for an extended time (the last week due to a bit of
> "political unrest" :-), and just returned yesterday...
> 
> On 07/26/2016 07:18 AM, Anton Khramov wrote:
>> Hi Cole,
>>
>> Any news on this change?
>>
>> Regards,
>> Anton
>>
>> On 07/18/2016 11:46 PM, Cole Robinson wrote:
>>> On 07/13/2016 07:06 AM, Khramov Anton wrote:
>>>> From: Anton Khramov <anton at endocode.com>
>>>>
>>>> Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1181539
>>>> ---
>>>>   docs/hooks.html.in          | 2 ++
>>>>   src/network/bridge_driver.c | 6 ++++++
>>>>   src/util/virhook.c          | 3 ++-
>>>>   src/util/virhook.h          | 1 +
>>>>   4 files changed, 11 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/docs/hooks.html.in b/docs/hooks.html.in
>>>> index 1aae00c..d4f4ac3 100644
>>>> --- a/docs/hooks.html.in
>>>> +++ b/docs/hooks.html.in
>>>> @@ -250,6 +250,8 @@
>>>>             <pre>/etc/libvirt/hooks/network network_name plugged begin
>>>> -</pre>
>>>>           Please note, that in this case, the script is passed both
>>>> network and
>>>>           domain XMLs on its stdin.</li>
>>>> +      <li>When network is updated, the hook script is called as:<br/>
>>>> +          <pre>/etc/libvirt/hooks/network network_name updated begin
>>>> -</pre></li>
>>>>         <li>When the domain from previous case is shutting down, the
>>>> interface
>>>>           is unplugged. This leads to another script invocation:<br/>
>>>>             <pre>/etc/libvirt/hooks/network network_name unplugged begin
>>>> -</pre>
>>>> diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c
>>>> index 0fd2095..61ab17b 100644
>>>> --- a/src/network/bridge_driver.c
>>>> +++ b/src/network/bridge_driver.c
>>>> @@ -3460,6 +3460,12 @@ networkUpdate(virNetworkPtr net,
>>>>               goto cleanup;
>>>>           }
>>>>       }
>>>> +
>>>> +    /* call the 'updated' network hook script */
>>>> +    if (networkRunHook(network, NULL, NULL, VIR_HOOK_NETWORK_OP_UPDATED,
>>>> +                       VIR_HOOK_SUBOP_BEGIN) < 0)
>>>> +        goto cleanup;
>>>> +
>>>>       ret = 0;
>>>>    cleanup:
>>>>       virNetworkObjEndAPI(&network);
>>>> diff --git a/src/util/virhook.c b/src/util/virhook.c
>>>> index d37d6da..a8422a2 100644
>>>> --- a/src/util/virhook.c
>>>> +++ b/src/util/virhook.c
>>>> @@ -93,7 +93,8 @@ VIR_ENUM_IMPL(virHookNetworkOp, VIR_HOOK_NETWORK_OP_LAST,
>>>>                 "started",
>>>>                 "stopped",
>>>>                 "plugged",
>>>> -              "unplugged")
>>>> +              "unplugged",
>>>> +              "updated")
>>>>     static int virHooksFound = -1;
>>>>   diff --git a/src/util/virhook.h b/src/util/virhook.h
>>>> index 550ef84..4015426 100644
>>>> --- a/src/util/virhook.h
>>>> +++ b/src/util/virhook.h
>>>> @@ -82,6 +82,7 @@ typedef enum {
>>>>       VIR_HOOK_NETWORK_OP_STOPPED,        /* network has stopped */
>>>>       VIR_HOOK_NETWORK_OP_IFACE_PLUGGED,  /* an interface has been plugged
>>>> into the network */
>>>>       VIR_HOOK_NETWORK_OP_IFACE_UNPLUGGED,    /* an interface was
>>>> unplugged from the network */
>>>> +    VIR_HOOK_NETWORK_OP_UPDATED,        /* network has been updated */
>>>>         VIR_HOOK_NETWORK_OP_LAST,
>>>>   } virHookNetworkOpType;
>>>>
>>> ACK this looks good to me. CCing laine to see if he wants to ACK when he's
>>> back online, if not I'll push it in a week.
> 
> This looks okay to me too, although I momentarily wondered if the sub-op
> should be VIR_HOOK_SUBOP_END, since this is happening after the update is
> finished. But then I realized that the hook name itself is saying that the
> update has already happened (it is "UPDATED", not "UPDATE"), so I think that's
> okay (it's also the way the IFACE_PLUGGED AND IFACE_UNPLUGGED hooks are handled).
> 
> (When I looked back to the discussion of the previous version of the patch, it
> made me realize that a hook run when a network's firewall is reloaded would
> also be useful, but that's a separate issue (iptables rules are reloaded 1)
> when libvirtd gets a SIGHUP, 2) when libvirtd is restarted, or 3) when
> firewalld is reloaded). Anyway there really is no end to the places a hook
> could potentially be useful, so trying to get ahead of it is a losing
> proposition).
> 
> So yeah, it's fine with me to push it.

Thanks, I've pushed the patch now. Thanks for your patience Anton!

- Cole