Add E2E tests for basic functionality and port launching to Go

This adds a new E2E test suite replacing the old log-parsing
based one. It also moves launching and controlling Smalltown VMs into
a Go package and command and exposes the '//:launch' alias.
The new E2E test suite covers basic conditions (IP assigned, Data
available) and Kubernetes Node, Deployment and StatefulSet tests.

Test Plan: This consists of E2E tests

X-Origin-Diff: phab/D544
GitOrigin-RevId: 7c624c667c849068bafa544a3a6c635d6d406e1c
diff --git a/core/tests/e2e/main_test.go b/core/tests/e2e/main_test.go
new file mode 100644
index 0000000..d400b9b
--- /dev/null
+++ b/core/tests/e2e/main_test.go
@@ -0,0 +1,169 @@
+// Copyright 2020 The Monogon Project Authors.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package e2e
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"log"
+	"net/http"
+	_ "net/http"
+	_ "net/http/pprof"
+	"os"
+	"testing"
+	"time"
+
+	"google.golang.org/grpc"
+	corev1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	podv1 "k8s.io/kubernetes/pkg/api/v1/pod"
+
+	apipb "git.monogon.dev/source/nexantic.git/core/generated/api"
+	"git.monogon.dev/source/nexantic.git/core/internal/common"
+	"git.monogon.dev/source/nexantic.git/core/internal/launch"
+)
+
+// TestE2E is the main E2E test entrypoint for single-node freshly-bootstrapped E2E tests. It starts a full Smalltown node
+// in bootstrap mode and then runs tests against it. The actual tests it performs are located in the RunGroup subtest.
+func TestE2E(t *testing.T) {
+	go func() {
+		log.Println(http.ListenAndServe("localhost:0", nil))
+	}()
+	// Set a global timeout to make sure this terminates
+	ctx, cancel := context.WithTimeout(context.Background(), 120*time.Second)
+	defer cancel()
+	portMap, err := launch.ConflictFreePortMap()
+	if err != nil {
+		t.Fatalf("Failed to acquire ports for e2e test: %v", err)
+	}
+	go func() {
+		if err := launch.Launch(ctx, launch.Options{Ports: portMap}); err != nil {
+			panic(err)
+		}
+	}()
+	grpcClient, err := portMap.DialGRPC(common.DebugServicePort, grpc.WithInsecure())
+	if err != nil {
+		fmt.Printf("Failed to dial debug service (is it running): %v\n", err)
+	}
+	debugClient := apipb.NewNodeDebugServiceClient(grpcClient)
+
+	go func() {
+		<-ctx.Done()
+		fmt.Fprintf(os.Stderr, "Main context canceled\n")
+	}()
+
+	// This exists to keep the parent around while all the children race
+	// It currently tests both a set of OS-level conditions and Kubernetes Deployments and StatefulSets
+	t.Run("RunGroup", func(t *testing.T) {
+		t.Run("IP available", func(t *testing.T) {
+			t.Parallel()
+			const timeoutSec = 10
+			ctx, cancel := context.WithTimeout(ctx, timeoutSec*time.Second)
+			defer cancel()
+			if err := waitForCondition(ctx, debugClient, "IPAssigned"); err != nil {
+				t.Errorf("Condition IPAvailable not met in %vs: %v", timeoutSec, err)
+			}
+		})
+		t.Run("Data available", func(t *testing.T) {
+			t.Parallel()
+			const timeoutSec = 30
+			ctx, cancel := context.WithTimeout(ctx, timeoutSec*time.Second)
+			defer cancel()
+			if err := waitForCondition(ctx, debugClient, "DataAvailable"); err != nil {
+				t.Errorf("Condition DataAvailable not met in %vs: %v", timeoutSec, err)
+			}
+		})
+		t.Run("Get Kubernetes Debug Kubeconfig", func(t *testing.T) {
+			t.Parallel()
+			selfCtx, cancel := context.WithTimeout(ctx, 30*time.Second)
+			defer cancel()
+			clientSet, err := getKubeClientSet(selfCtx, debugClient, portMap[common.KubernetesAPIPort])
+			if err != nil {
+				t.Fatal(err)
+			}
+			testEventual(t, "Node is registered and ready", ctx, 30*time.Second, func(ctx context.Context) error {
+				nodes, err := clientSet.CoreV1().Nodes().List(ctx, metav1.ListOptions{})
+				if err != nil {
+					return err
+				}
+				if len(nodes.Items) < 1 {
+					return errors.New("node not registered")
+				}
+				if len(nodes.Items) > 1 {
+					return errors.New("more than one node registered (but there is only one)")
+				}
+				node := nodes.Items[0]
+				for _, cond := range node.Status.Conditions {
+					if cond.Type != corev1.NodeReady {
+						continue
+					}
+					if cond.Status != corev1.ConditionTrue {
+						return fmt.Errorf("node not ready: %v", cond.Message)
+					}
+				}
+				return nil
+			})
+			testEventual(t, "Simple deployment", ctx, 30*time.Second, func(ctx context.Context) error {
+				_, err := clientSet.AppsV1().Deployments("default").Create(ctx, makeTestDeploymentSpec("test-deploy-1"), metav1.CreateOptions{})
+				return err
+			})
+			testEventual(t, "Simple deployment is running", ctx, 40*time.Second, func(ctx context.Context) error {
+				res, err := clientSet.CoreV1().Pods("default").List(ctx, metav1.ListOptions{LabelSelector: "name=test-deploy-1"})
+				if err != nil {
+					return err
+				}
+				if len(res.Items) == 0 {
+					return errors.New("pod didn't get created")
+				}
+				pod := res.Items[0]
+				if podv1.IsPodAvailable(&pod, 1, metav1.NewTime(time.Now())) {
+					return nil
+				}
+				events, err := clientSet.CoreV1().Events("default").List(ctx, metav1.ListOptions{FieldSelector: fmt.Sprintf("involvedObject.name=%s,involvedObject.namespace=default", pod.Name)})
+				if err != nil || len(events.Items) == 0 {
+					return fmt.Errorf("pod is not ready: %v", pod.Status.Phase)
+				} else {
+					return fmt.Errorf("pod is not ready: %v", events.Items[0].Message)
+				}
+			})
+			testEventual(t, "Simple StatefulSet with PVC", ctx, 30*time.Second, func(ctx context.Context) error {
+				_, err := clientSet.AppsV1().StatefulSets("default").Create(ctx, makeTestStatefulSet("test-statefulset-1"), metav1.CreateOptions{})
+				return err
+			})
+			testEventual(t, "Simple StatefulSet with PVC is running", ctx, 40*time.Second, func(ctx context.Context) error {
+				res, err := clientSet.CoreV1().Pods("default").List(ctx, metav1.ListOptions{LabelSelector: "name=test-statefulset-1"})
+				if err != nil {
+					return err
+				}
+				if len(res.Items) == 0 {
+					return errors.New("pod didn't get created")
+				}
+				pod := res.Items[0]
+				if podv1.IsPodAvailable(&pod, 1, metav1.NewTime(time.Now())) {
+					return nil
+				}
+				events, err := clientSet.CoreV1().Events("default").List(ctx, metav1.ListOptions{FieldSelector: fmt.Sprintf("involvedObject.name=%s,involvedObject.namespace=default", pod.Name)})
+				if err != nil || len(events.Items) == 0 {
+					return fmt.Errorf("pod is not ready: %v", pod.Status.Phase)
+				} else {
+					return fmt.Errorf("pod is not ready: %v", events.Items[0].Message)
+				}
+			})
+		})
+	})
+}