Currently container can join one endpoint when it is started. More endpoints can be attached at a later point in time. But when that happens this attachment should only have meaning only as long as the container is alive. The attachment should lose it's meaning when the container goes away. Cuurently there is no way for the container management code to tell libnetwork to detach the container from all attached endpoints. This PR provides an additional API `LeaveAll` which adds this functionality, To facilitate this and make the sanbox lifecycle consistent some slight changes have been made to the behavior of sandbox management code. The sandbox is no longer destroyed when the last endpoint is detached from the container. Instead the sandbox ie kept alive and can only be destroyed with a `LeaveAll` call. This gives better control of sandbox lifecycle by the container management code and the sandbox doesn't get destroyed from under the carpet while the container is still using it. Signed-off-by: Jana Radhakrishnan <mrjana@docker.com>
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.
// 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.