diff options
Diffstat (limited to 'plugin/kubernetes/setup.go')
| -rw-r--r-- | plugin/kubernetes/setup.go | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/plugin/kubernetes/setup.go b/plugin/kubernetes/setup.go new file mode 100644 index 000000000..e60239d42 --- /dev/null +++ b/plugin/kubernetes/setup.go @@ -0,0 +1,208 @@ +package kubernetes + +import ( + "errors" + "fmt" + "strconv" + "strings" + "time" + + "github.com/coredns/coredns/core/dnsserver" + "github.com/coredns/coredns/plugin" + "github.com/coredns/coredns/plugin/pkg/dnsutil" + "github.com/coredns/coredns/plugin/proxy" + "github.com/miekg/dns" + + "github.com/mholt/caddy" + unversionedapi "k8s.io/client-go/1.5/pkg/api/unversioned" +) + +func init() { + caddy.RegisterPlugin("kubernetes", caddy.Plugin{ + ServerType: "dns", + Action: setup, + }) +} + +func setup(c *caddy.Controller) error { + kubernetes, initOpts, err := kubernetesParse(c) + if err != nil { + return plugin.Error("kubernetes", err) + } + + err = kubernetes.initKubeCache(initOpts) + if err != nil { + return plugin.Error("kubernetes", err) + } + + // Register KubeCache start and stop functions with Caddy + c.OnStartup(func() error { + go kubernetes.APIConn.Run() + if kubernetes.APIProxy != nil { + go kubernetes.APIProxy.Run() + } + return nil + }) + + c.OnShutdown(func() error { + if kubernetes.APIProxy != nil { + kubernetes.APIProxy.Stop() + } + return kubernetes.APIConn.Stop() + }) + + dnsserver.GetConfig(c).AddPlugin(func(next plugin.Handler) plugin.Handler { + kubernetes.Next = next + return kubernetes + }) + + return nil +} + +func kubernetesParse(c *caddy.Controller) (*Kubernetes, dnsControlOpts, error) { + k8s := New([]string{""}) + k8s.interfaceAddrsFunc = localPodIP + k8s.autoPathSearch = searchFromResolvConf() + + opts := dnsControlOpts{ + resyncPeriod: defaultResyncPeriod, + } + + for c.Next() { + zones := c.RemainingArgs() + + if len(zones) != 0 { + k8s.Zones = zones + for i := 0; i < len(k8s.Zones); i++ { + k8s.Zones[i] = plugin.Host(k8s.Zones[i]).Normalize() + } + } else { + k8s.Zones = make([]string, len(c.ServerBlockKeys)) + for i := 0; i < len(c.ServerBlockKeys); i++ { + k8s.Zones[i] = plugin.Host(c.ServerBlockKeys[i]).Normalize() + } + } + + k8s.primaryZoneIndex = -1 + for i, z := range k8s.Zones { + if strings.HasSuffix(z, "in-addr.arpa.") || strings.HasSuffix(z, "ip6.arpa.") { + continue + } + k8s.primaryZoneIndex = i + break + } + + if k8s.primaryZoneIndex == -1 { + return nil, opts, errors.New("non-reverse zone name must be used") + } + + for c.NextBlock() { + switch c.Val() { + case "pods": + args := c.RemainingArgs() + if len(args) == 1 { + switch args[0] { + case podModeDisabled, podModeInsecure, podModeVerified: + k8s.podMode = args[0] + default: + return nil, opts, fmt.Errorf("wrong value for pods: %s, must be one of: disabled, verified, insecure", args[0]) + } + continue + } + return nil, opts, c.ArgErr() + case "namespaces": + args := c.RemainingArgs() + if len(args) > 0 { + for _, a := range args { + k8s.Namespaces[a] = true + } + continue + } + return nil, opts, c.ArgErr() + case "endpoint": + args := c.RemainingArgs() + if len(args) > 0 { + for _, endpoint := range strings.Split(args[0], ",") { + k8s.APIServerList = append(k8s.APIServerList, strings.TrimSpace(endpoint)) + } + continue + } + return nil, opts, c.ArgErr() + case "tls": // cert key cacertfile + args := c.RemainingArgs() + if len(args) == 3 { + k8s.APIClientCert, k8s.APIClientKey, k8s.APICertAuth = args[0], args[1], args[2] + continue + } + return nil, opts, c.ArgErr() + case "resyncperiod": + args := c.RemainingArgs() + if len(args) > 0 { + rp, err := time.ParseDuration(args[0]) + if err != nil { + return nil, opts, fmt.Errorf("unable to parse resync duration value: '%v': %v", args[0], err) + } + opts.resyncPeriod = rp + continue + } + return nil, opts, c.ArgErr() + case "labels": + args := c.RemainingArgs() + if len(args) > 0 { + labelSelectorString := strings.Join(args, " ") + ls, err := unversionedapi.ParseToLabelSelector(labelSelectorString) + if err != nil { + return nil, opts, fmt.Errorf("unable to parse label selector value: '%v': %v", labelSelectorString, err) + } + opts.labelSelector = ls + continue + } + return nil, opts, c.ArgErr() + case "fallthrough": + args := c.RemainingArgs() + if len(args) == 0 { + k8s.Fallthrough = true + continue + } + return nil, opts, c.ArgErr() + case "upstream": + args := c.RemainingArgs() + if len(args) == 0 { + return nil, opts, c.ArgErr() + } + ups, err := dnsutil.ParseHostPortOrFile(args...) + if err != nil { + return nil, opts, err + } + k8s.Proxy = proxy.NewLookup(ups) + case "ttl": + args := c.RemainingArgs() + if len(args) == 0 { + return nil, opts, c.ArgErr() + } + t, err := strconv.Atoi(args[0]) + if err != nil { + return nil, opts, err + } + if t < 5 || t > 3600 { + return nil, opts, c.Errf("ttl must be in range [5, 3600]: %d", t) + } + k8s.ttl = uint32(t) + default: + return nil, opts, c.Errf("unknown property '%s'", c.Val()) + } + } + } + return k8s, opts, nil +} + +func searchFromResolvConf() []string { + rc, err := dns.ClientConfigFromFile("/etc/resolv.conf") + if err != nil { + return nil + } + plugin.Zones(rc.Search).Normalize() + return rc.Search +} + +const defaultResyncPeriod = 5 * time.Minute |