// watchKeys creates a new Watcher and adds all configured keys
func watchKeys(config Config, etcdClient *etcd.Client) *watcher.Watcher {
w, err := watcher.New(etcdClient)
if err != nil {
log.WithField("error", err).Fatal("failed to create watcher")
}
// start watching etcd prefixs
for prefix := range config {
if err := w.Add(prefix); err != nil {
log.WithFields(log.Fields{
"prefix": prefix,
"error": err,
"errorMsg": err.Error(),
}).Fatal("failed to add watch prefix")
}
}
return w
}
func main() {
eaddr := "http://localhost:4001"
hn := ""
rules := "/etc/nftables.conf"
flag.StringVarP(&eaddr, "etcd", "e", eaddr, "etcd cluster address")
flag.StringVarP(&hn, "id", "i", hn, "hypervisor id")
flag.StringVarP(&rules, "file", "f", rules, "nft configuration file")
flag.Parse()
rules = canonicalizeRules(rules)
cleanStaleFiles(rules)
e := etcd.NewClient([]string{eaddr})
c := ln.NewContext(e)
hv := getHV(hn, e, c)
watcher, err := watcher.New(e)
if err != nil {
log.WithFields(log.Fields{
"error": err,
"func": "watcher.New",
}).Fatal("failed to start watcher")
}
if err = watcher.Add("/lochness/guests"); err != nil {
log.WithFields(log.Fields{
"error": err,
"func": "watcher.Add",
"prefix": "/lochness/guests",
}).Fatal("failed to add prefix to watch list")
}
if err := watcher.Add("/lochness/fwgroups"); err != nil {
log.WithFields(log.Fields{
"error": err,
"func": "watcher.Add",
"prefix": "/lochness/fwgroups",
}).Fatal("failed to add prefix to watch list")
}
// load rules at startup
td, err := genRules(hv, c)
if err != nil {
log.WithField("error", err).Fatal("could not load intial rules")
}
if err := applyRules(rules, td); err != nil {
log.WithField("error", err).Fatal("could not apply intial rules")
}
for watcher.Next() {
td, err := genRules(hv, c)
if err != nil {
continue
}
if err := applyRules(rules, td); err != nil {
log.WithField("error", err).Fatal("could not apply rules")
}
}
if err := watcher.Err(); err != nil {
log.Fatal(err)
}
}
func main() {
// Command line options
var etcdAddress, domain, confPath, logLevel string
flag.StringVarP(&domain, "domain", "d", "", "domain for lochness; required")
flag.StringVarP(&etcdAddress, "etcd", "e", "http://127.0.0.1:4001", "address of etcd server")
flag.StringVarP(&confPath, "conf-dir", "c", "/etc/dhcp/", "dhcpd configuration directory")
flag.StringVarP(&logLevel, "log-level", "l", "warning", "log level: debug/info/warning/error/critical/fatal")
flag.Parse()
// Domain is required
if domain == "" {
flag.PrintDefaults()
os.Exit(1)
}
// Logging
if err := logx.DefaultSetup(logLevel); err != nil {
log.WithFields(log.Fields{
"error": err,
"func": "logx.DefaultSetup",
}).Fatal("Could not set up logrus")
}
hconfPath := path.Join(confPath, "hypervisors.conf")
gconfPath := path.Join(confPath, "guests.conf")
// Set up fetcher and refresher
f := NewFetcher(etcdAddress)
r := NewRefresher(domain)
err := f.FetchAll()
if err != nil {
os.Exit(1)
}
// Update at the start of each run
restart, err := updateConfigs(f, r, hconfPath, gconfPath)
if restart {
restartDhcpd()
}
if err != nil {
os.Exit(1)
}
// Create the watcher
w, err := watcher.New(f.etcdClient)
if err != nil {
log.WithFields(log.Fields{
"error": err,
"func": "watcher.New",
}).Fatal("Could not create watcher")
}
// Start watching the necessary etcd prefixs
prefixes := [...]string{"/lochness/hypervisors", "/lochness/guests", "/lochness/subnets"}
for _, prefix := range prefixes {
if err := w.Add(prefix); err != nil {
log.WithFields(log.Fields{
"error": err,
"func": "watcher.Add",
"prefix": prefix,
}).Fatal("Could not add watch prefix")
}
}
// Channel for indicating work in progress
// (to coordinate clean exiting between the consumer and the signal handler)
ready := make(chan struct{}, 1)
ready <- struct{}{}
for w.Next() {
// Remove item to indicate processing has begun
done := <-ready
// Integrate the response and update the configs if necessary
refresh, err := f.IntegrateResponse(w.Response())
if err != nil {
log.Info("Error on integration; re-fetching")
err := f.FetchAll()
if err != nil {
os.Exit(1)
}
refresh = true
}
if refresh {
restart, err := updateConfigs(f, r, hconfPath, gconfPath)
if restart {
restartDhcpd()
}
if err != nil {
log.WithFields(log.Fields{
"error": err,
"func": "updateConfigs",
}).Warn("Could not create watcher")
}
}
// Return item to indicate processing has completed
ready <- done
}
if err := w.Err(); err != nil {
log.WithField("error", err).Fatal("Watcher encountered an error")
}
// Handle signals for clean shutdown
sigs := make(chan os.Signal)
signal.Notify(sigs, os.Interrupt, syscall.SIGTERM)
s := <-sigs
log.WithField("signal", s).Info("Signal received; waiting for current task to process")
<-ready // wait until any current processing is finished
_ = w.Close()
log.Info("Exiting")
}