The openflow library is a pure Go implementation of the OpenFlow protocol. The ideas of the programming interface mostly borrowed from the Go standard HTTP library.
$ go get github.com/netrack/openflowThe usage is pretty similar to the handling HTTP request, but instead of routes we are using message types.
package main import ( of "github.com/netrack/openflow" ) func main() { // Define the OpenFlow handler for hello messages. of.HandleFunc(of.TypeHello, func(rw of.ResponseWriter, r *of.Request) { // Send back hello response. rw.Write(&of.Header{Type: of.TypeHello}, nil) }) // Start the TCP server on 6633 port. of.ListenAndServe(":6633", nil) }package main import ( "github.com/netrack/openflow/ofp" of "github.com/netrack/openflow" ) func main() { pattern := of.TypeMatcher(of.TypePacketIn) mux := of.NewServeMux() mux.HandleFunc(pattern, func(rw of.ResponseWriter, r *of.Request) { var packet ofp.PacketIn packet.ReadFrom(r.Body) apply := &ofp.InstructionApplyActions{ ofp.Actions{&ofp.ActionOutput{ofp.PortFlood, 0}}, } // For each incoming packet-in request, create a // respective flow modification command. fmod := ofp.NewFlowMod(ofp.FlowAdd, packet) fmod.Instructions = ofp.Instructions{apply} rw.Write(&of.Header{Type: of.TypeFlowMod}, fmod) }) of.ListenAndServe(":6633", mux) }The openflow library is distributed under MIT license, therefore you are free to do with code whatever you want. See the LICENSE file for full license text.