Regenerating the ZK connection was fraught with issues, including
duplicate connections, strange failures to reconnect, and various other
wonkiness.
Instead let Kazoo handle states sensibly. Kazoo moves to SUSPENDED state
when it loses connectivity, and stays there indefinitely (based on
cursory tests). And Kazoo seems to always resume from this just fine on
its own. Thus all that hackery did nothing but complicate reconnection.
This therefore turns the listener into a purely informational function,
providing logs of when/why it failed, and we also add some additional
output messages during initial connection and final disconnection.
When trying to write to sub-item paths that don't yet exist, the
previous method would just blindly write to whatever the root key is,
which is never what we actually want.
Instead, check explicitly for a "base path" situation, and handle that.
Then, if we try to get a subpath that isn't valid, return None. Finally
in the various functions, if the path is None, just continue (or return
false/None) and (try to) chug along.
Instead of looping 5+ times acquiring an impossible lock on a
nonexistent key, just fail on a different error and return failure
immediately.
This is likely a major corner case that shouldn't happen, but better to
be safe than 500.
These cause a major (2x) slowdown in read calls since Zookeeper
connections are expensive/slow. Instead, just try the thing and return
None if there's no key there.
Also wrap the children command in similar error handling since that did
not exist and could likely cause some bugs at some point.
Adds support for the node daemon managing SR-IOV PF and VF instances.
PFs are added to Zookeeper automatically based on the config at startup
during network configuration, and are otherwise completely static. PFs
are automatically removed from Zookeeper, along with all coresponding
VFs, should the PF phy device be removed from the configuration.
VFs are configured based on the (autocreated) VFs of each PF device,
added to Zookeeper, and then a new class instance, SRIOVVFInstance, is
used to watch them for configuration changes. This will enable the
runtime management of VF settings by the API. The set of keys ensures
that both configuration and details of the NIC can be tracked.
Most keys are self-explanatory, especially for PFs and the basic keys
for VFs. The configuration tree is also self-explanatory, being based
entirely on the options available in the `ip link set {dev} vf` command.
Two additional keys are also present: `used` and `used_by`, which will
be able to track the (boolean) state of usage, as well as the VM that
uses a given VIF. Since the VM side implementation will support both
macvtap and direct "hostdev" assignments, this will ensure that this
state can be tracked on both the VF and the VM side.
Required a bit of refactoring in the validation code to ensure we have
direct access, without relying on the translations done in the normal
zkhandler functions.
Adds a new class, ZKSchema, to handle schema management in Zookeeper in
an automated and consistent way. This should solve several issues:
1. Pain in managing changes to ZK keys
2. Pain in handling those changes during live upgrades
3. Simplifying the codebase to remove hardcoded ZK paths
The current master schema for PVC 0.9.19 is committed as version 0.
Addresses #129
Joshua Boniface