osdconfig

osdconfig is a library to work with distributed configuration parameters. It defines an interface and provides an implementation against KVDB backend.

General purpose of this package is as follows:

• Allow users to register their callback functions on updates to backend
• Allow users to set/get config parameters

installation

osdconfig is written in go (golang). It can be installed using go get

$ go get github.com/libopenstorage/openstorage/osdconfig/...

example

Create an instance of kvdb

kv, err := kvdb.New(mem.Name, "", []string{}, nil, nil)
if err != nil {
    logrus.Fatal(err)
}

Create an instance of osdconfig manager

manager, err := osdconfig.NewManager(kv)
if err != nil {
	// do something
}
defer manager.Close()

Define a function literal that can be registered to watch for changes

f := func(config *osdconfig.Config) error {
	// do something with config (say print)
	fmt.Println(config)
	return nil
}

Register this function literal to watch on kvdb changes

if err := manager.WatchCluster("watcher", f); err != nil {
	// do something
}

Update cluster config on kvdb

conf := new(osdconfig.ClusterConfig)
conf.ClusterID = "myID"
if err := manager.SetClusterConf(conf); err != nil {
	// do something
	return
}

once updates are pushed to backend (kvdb in this implementation), callback function is called