network enhanecment / refactor (#361)

* chore(network): improve connectivity check

* refactor(network): rewrite network and timesync component

* feat(display): show cloud connection status

* chore: change logging verbosity

* chore(websecure): update log message

* fix(ota): validate root certificate when downloading update

* feat(ui): add network settings tab

* fix(display): cloud connecting animation

* fix: golintci issues

* feat: add network settings tab

* feat(timesync): query servers in parallel

* refactor(network): move to internal/network package

* feat(timesync): add metrics

* refactor(log): move log to internal/logging package

* refactor(mdms): move mdns to internal/mdns package

* feat(developer): add pprof endpoint

* feat(logging): add a simple logging streaming endpoint

* fix(mdns): do not start mdns until network is up

* feat(network): allow users to update network settings from ui

* fix(network): handle errors when net.IPAddr is nil

* fix(mdns): scopedLogger SIGSEGV

* fix(dhcp): watch directory instead of file to catch fsnotify.Create event

* refactor(nbd): move platform-specific code to different files

* refactor(native): move platform-specific code to different files

* chore: fix linter issues

* chore(dev_deploy): allow to override PION_LOG_TRACE

internal/network/netif_linux.go

@@ -0,0 +1,58 @@
+//go:build linux
+
+package network
+
+import (
+	"time"
+
+	"github.com/vishvananda/netlink"
+	"github.com/vishvananda/netlink/nl"
+)
+
+func (s *NetworkInterfaceState) HandleLinkUpdate(update netlink.LinkUpdate) {
+	if update.Link.Attrs().Name == s.interfaceName {
+		s.l.Info().Interface("update", update).Msg("interface link update received")
+		_ = s.CheckAndUpdateDhcp()
+	}
+}
+
+func (s *NetworkInterfaceState) Run() error {
+	updates := make(chan netlink.LinkUpdate)
+	done := make(chan struct{})
+
+	if err := netlink.LinkSubscribe(updates, done); err != nil {
+		s.l.Warn().Err(err).Msg("failed to subscribe to link updates")
+		return err
+	}
+
+	_ = s.setHostnameIfNotSame()
+
+	// run the dhcp client
+	go s.dhcpClient.Run() // nolint:errcheck
+
+	if err := s.CheckAndUpdateDhcp(); err != nil {
+		return err
+	}
+
+	go func() {
+		ticker := time.NewTicker(1 * time.Second)
+		defer ticker.Stop()
+
+		for {
+			select {
+			case update := <-updates:
+				s.HandleLinkUpdate(update)
+			case <-ticker.C:
+				_ = s.CheckAndUpdateDhcp()
+			case <-done:
+				return
+			}
+		}
+	}()
+
+	return nil
+}
+
+func netlinkAddrs(iface netlink.Link) ([]netlink.Addr, error) {
+	return netlink.AddrList(iface, nl.FAMILY_ALL)
+}