ok

contrib/discovery/k8s/k8s.go

+package k8s
+
+import (
+	"context"
+	"fmt"
+	"pggat2/lib/gat"
+
+	"tuxpa.in/a/zlog/log"
+
+	"golang.org/x/sync/errgroup"
+	v1 "k8s.io/api/core/v1"
+	"k8s.io/client-go/kubernetes"
+
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+type PodWatcher struct {
+	BaseRecipe gat.Recipe
+
+	Namespace   string
+	ListOptions metav1.ListOptions
+
+	pods map[string]*v1.Pod
+}
+
+func (p *PodWatcher) Start(
+	pctx context.Context,
+	c *kubernetes.Clientset,
+	pool gat.Pool,
+) error {
+	p.pods = make(map[string]*v1.Pod)
+	egg, ctx := errgroup.WithContext(pctx)
+	egg.Go(func() error {
+		return p.startWatching(ctx, c, pool)
+	})
+	err := p.getInitialPods(ctx, c, pool)
+	if err != nil {
+		return err
+	}
+
+	return egg.Wait()
+}
+
+func (p *PodWatcher) getInitialPods(
+	ctx context.Context,
+	c *kubernetes.Clientset,
+	pool gat.Pool,
+) error {
+	pods, err := c.CoreV1().Pods(p.Namespace).List(ctx, p.ListOptions)
+	if err != nil {
+		return err
+	}
+	for _, pod := range pods.Items {
+		if isPodReady(&pod) {
+			p.pods[pod.Name] = &pod
+		}
+	}
+	return nil
+}
+
+func (p *PodWatcher) startWatching(
+	ctx context.Context,
+	c *kubernetes.Clientset,
+	pool gat.Pool,
+) error {
+	watcher, err := c.CoreV1().Pods(p.Namespace).Watch(ctx, p.ListOptions)
+	if err != nil {
+		return err
+	}
+	defer watcher.Stop()
+
+	for event := range watcher.ResultChan() {
+		pod, ok := event.Object.(*v1.Pod)
+		if !ok {
+			continue
+		}
+
+		podName := pod.Name
+		podIp := pod.Status.PodIP
+		podReady := isPodReady(pod)
+
+		shouldDelete := false
+		shouldCreate := false
+
+		// Log raw event stream to debug log
+		switch event.Type {
+		case "ADDED":
+			log.Printf("ADDED pod %s with ip %s. Ready = %v", podName, podIp, podReady)
+			if podReady {
+				shouldCreate = true
+			} else {
+				shouldDelete = true
+			}
+
+		case "MODIFIED":
+			log.Printf("MODIFIED pod %s with ip %s. Ready = %v", podName, podIp, podReady)
+			if podReady {
+				shouldCreate = true
+			} else {
+				shouldDelete = true
+			}
+		case "DELETED":
+			log.Printf("DELETED pod %s with ip %s. Ready = %v", podName, podIp, podReady)
+			shouldDelete = true
+		}
+
+		if shouldDelete {
+			pool.RemoveRecipe(podName)
+			delete(p.pods, podName)
+		} else if shouldCreate {
+			r := p.BaseRecipe
+			r.Address = fmt.Sprintf(r.Address, pod.Status.PodIP)
+			pool.AddRecipe(podName, r)
+		}
+
+	}
+
+	return nil
+}
+
+func isPodReady(pod *v1.Pod) bool {
+	for _, condition := range pod.Status.Conditions {
+		if condition.Type == v1.PodReady && condition.Status == v1.ConditionTrue {
+			return true
+		}
+	}
+	return false
+}

go.mod

@@ -3,9 +3,53 @@ module pggat2
 go 1.20
 
 require (
-	github.com/google/uuid v1.3.0 // indirect
+	github.com/google/uuid v1.3.0
+	github.com/xdg-go/scram v1.1.2
+	golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4
+	k8s.io/api v0.27.4
+	k8s.io/apimachinery v0.27.4
+	k8s.io/client-go v0.27.4
+	tuxpa.in/a/zlog v1.61.0
+)
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/emicklei/go-restful/v3 v3.9.0 // indirect
+	github.com/go-logr/logr v1.2.3 // indirect
+	github.com/go-openapi/jsonpointer v0.19.6 // indirect
+	github.com/go-openapi/jsonreference v0.20.1 // indirect
+	github.com/go-openapi/swag v0.22.3 // indirect
+	github.com/gogo/protobuf v1.3.2 // indirect
+	github.com/golang/protobuf v1.5.3 // indirect
+	github.com/google/gnostic v0.5.7-v3refs // indirect
+	github.com/google/go-cmp v0.5.9 // indirect
+	github.com/google/gofuzz v1.1.0 // indirect
+	github.com/josharian/intern v1.0.0 // indirect
+	github.com/json-iterator/go v1.1.12 // indirect
+	github.com/mailru/easyjson v0.7.7 // indirect
+	github.com/mattn/go-colorable v0.1.12 // indirect
+	github.com/mattn/go-isatty v0.0.14 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.2 // indirect
+	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
+	github.com/rs/zerolog v1.28.0 // indirect
 	github.com/xdg-go/pbkdf2 v1.0.0 // indirect
-	github.com/xdg-go/scram v1.1.2 // indirect
 	github.com/xdg-go/stringprep v1.0.4 // indirect
-	golang.org/x/text v0.3.8 // indirect
+	golang.org/x/net v0.8.0 // indirect
+	golang.org/x/oauth2 v0.0.0-20220223155221-ee480838109b // indirect
+	golang.org/x/sys v0.6.0 // indirect
+	golang.org/x/term v0.6.0 // indirect
+	golang.org/x/text v0.8.0 // indirect
+	golang.org/x/time v0.0.0-20220210224613-90d013bbcef8 // indirect
+	google.golang.org/appengine v1.6.7 // indirect
+	google.golang.org/protobuf v1.28.1 // indirect
+	gopkg.in/inf.v0 v0.9.1 // indirect
+	gopkg.in/yaml.v2 v2.4.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+	k8s.io/klog/v2 v2.90.1 // indirect
+	k8s.io/kube-openapi v0.0.0-20230501164219-8b0f38b5fd1f // indirect
+	k8s.io/utils v0.0.0-20230209194617-a36077c30491 // indirect
+	sigs.k8s.io/json v0.0.0-20221116044647-bc3834ca7abd // indirect
+	sigs.k8s.io/structured-merge-diff/v4 v4.2.3 // indirect
+	sigs.k8s.io/yaml v1.3.0 // indirect
 )