With the introduction of a driver generic gossip in libnetwork it is not
necessary for drivers to run their own gossip protocol (like what
overlay driver is doing currently) but instead rely on the gossip
instance run centrally in libnetwork. In order to achieve this, certain
enhancements to driver api are needed. This api aims to provide these
enhancements.
The new api provides a way for drivers to register interest on table
names of their choice by returning a list of table names of interest as
a response to CreateNetwork. By doing that they will get notified if a
CRUD operation happened on the tables of their interest, via the newly
added EventNotify call.
Drivers themselves can add entries to any table during a Join call by
invoking AddTableEntry method any number of times during the Join
call. These entries lifetime is the same as the endpoint itself. As soon
as the container leaves the endpoint, those entries added by driver
during that endpoint's Join call will be automatically removed by
libnetwork. This action may trigger notification of such deletion to all
driver instances in the cluster who have registered interest in that
table's notification.
Signed-off-by: Jana Radhakrishnan <mrjana@docker.com>
Because overlay is a builtin driver and global allocation of overlay
resources is probably going to happen in a different node (a single
node) and the actual plumbing of the network is probably going to happen
in all nodes, it makes sense to split the functionality of allocation
into two different packages. The central component(this package) only
implements the NetworkAllocate/Free apis while the distributed
component(the existing overlay driver) implements the rest of the driver
api. This way we can reduce the memory footprint overall.
Signed-off-by: Jana Radhakrishnan <mrjana@docker.com>
Added NetworkAllocate and NetworkFree apis to the list of
driver apis. The intention of the api is to provide a
centralized way of allocating and freeing network resources
for a network which is cross-host.
Signed-off-by: Jana Radhakrishnan <mrjana@docker.com>
Alessandro Boch