Added a test binary to test README.md code

Signed-off-by: Jana Radhakrishnan <mrjana@docker.com>

libnetwork/cmd/readme_test/readme.go

@@ -0,0 +1,53 @@
+package main
+
+import (
+	"github.com/docker/libnetwork"
+	"github.com/docker/libnetwork/pkg/options"
+	"github.com/docker/libnetwork/sandbox"
+)
+
+func main() {
+	// Create a new controller instance
+	controller := libnetwork.New()
+
+	option := options.Generic{}
+	driver, err := controller.NewNetworkDriver("simplebridge", option)
+	if err != nil {
+		return
+	}
+
+	netOptions := options.Generic{}
+	// Create a network for containers to join.
+	network, err := controller.NewNetwork(driver, "network1", netOptions)
+	if err != nil {
+		return
+	}
+
+	// For a new container: create a sandbox instance (providing a unique key).
+	// For linux it is a filesystem path
+	networkPath := "/var/lib/docker/.../4d23e"
+	networkNamespace, err := sandbox.NewSandbox(networkPath)
+	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.
+	_, sinfo, err := network.CreateEndpoint("Endpoint1", networkNamespace.Key(), "")
+	if err != nil {
+		return
+	}
+
+	// Add interfaces to the namespace.
+	for _, iface := range sinfo.Interfaces {
+		if err := networkNamespace.AddInterface(iface); err != nil {
+			return
+		}
+	}
+
+	// Set the gateway IP
+	if err := networkNamespace.SetGateway(sinfo.Gateway); err != nil {
+		return
+	}
+}