b323d571b5
Refactored the driver api so that is aligns well with the design
of endpoint lifecycle becoming decoupled from the container lifecycle.
Introduced go interfaces to obtain address information during CreateEndpoint.
Go interfaces are also used to get data from driver during join.
This sort of deisgn hides the libnetwork specific type details from drivers.
Another adjustment is to provide a list of interfaces during CreateEndpoint. The
goal of this is many-fold:
* To indicate to the driver that IP address has been assigned by some other
entity (like a user wanting to use their own static IP for an endpoint/container)
and asking the driver to honor this. Driver may reject this configuration
and return an error but it may not try to allocate an IP address and override
the passed one.
* To indicate to the driver that IP address has already been allocated once
for this endpoint by an instance of the same driver in some docker host
in the cluster and this is merely a notification about that endpoint and the
allocated resources.
* In case the list of interfaces is empty the driver is required to allocate and
assign IP addresses for this endpoint.
Signed-off-by: Jana Radhakrishnan <mrjana@docker.com>
3.7 KiB
libnetwork - networking for containers
Libnetwork provides a native Go implementation for connecting containers
The goal of libnetwork is to deliver a robust Container Network Model that provides a consistent programming interface and the required network abstractions for applications.
NOTE: libnetwork project is under heavy development and is not ready for general use.
Design
Please refer to the design for more information.
Using libnetwork
There are many networking solutions available to suit a broad range of use-cases. libnetwork uses a driver / plugin model to support all of these solutions while abstracting the complexity of the driver implementations by exposing a simple and consistent Network Model to users.
// Create a new controller instance
controller := libnetwork.New()
// Select and configure the network driver
networkType := "bridge"
driverOptions := options.Generic{}
genericOption := make(map[string]interface{})
genericOption[netlabel.GenericData] = driverOptions
err := controller.ConfigureNetworkDriver(networkType, genericOption)
if err != nil {
return
}
// Create a network for containers to join.
// NewNetwork accepts Variadic optional arguments that libnetwork and Drivers can make of
network, err := controller.NewNetwork(networkType, "network1")
if err != nil {
return
}
// For each new container: allocate IP and interfaces. The returned network
// settings will be used for container infos (inspect and such), as well as
// iptables rules for port publishing. This info is contained or accessible
// from the returned endpoint.
ep, err := network.CreateEndpoint("Endpoint1")
if err != nil {
return
}
// A container can join the endpoint by providing the container ID to the join
// api which returns the sandbox key which can be used to access the sandbox
// created for the container during join.
// Join acceps Variadic arguments which will be made use of by libnetwork and Drivers
_, err = ep.Join("container1",
libnetwork.JoinOptionHostname("test"),
libnetwork.JoinOptionDomainname("docker.io"))
if err != nil {
return
}
// libentwork client can check the endpoint's operational data via the Info() API
epInfo, err := ep.DriverInfo()
mapData, ok := epInfo[netlabel.PortMap]
if ok {
portMapping, ok := mapData.([]netutils.PortBinding)
if ok {
fmt.Printf("Current port mapping for endpoint %s: %v", ep.Name(), portMapping)
}
}
Current Status
Please watch this space for updates on the progress.
Currently libnetwork is nothing more than an attempt to modularize the Docker platform's networking subsystem by moving it into libnetwork as a library.
Future
Please refer to roadmap for more information.
Contributing
Want to hack on libnetwork? Docker's contributions guidelines apply.
Copyright and license
Code and documentation copyright 2015 Docker, inc. Code released under the Apache 2.0 license. Docs released under Creative commons.