Add etcd launcher to test framework

This can be started and stopped the same way as the apiserver.

pkg/framework/test/assets/fakeetcd/etcd.go

@@ -0,0 +1,29 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"time"
+)
+
+func main() {
+	expectedArgs := []string{
+		"--advertise-client-urls",
+		"our etcd url",
+		"--data-dir",
+		"our data directory",
+		"--listen-client-urls",
+		"our etcd url",
+		"--debug",
+	}
+
+	for i, arg := range os.Args[1:] {
+		if arg != expectedArgs[i] {
+			fmt.Printf("Expected arg %s, got arg %s", expectedArgs[i], arg)
+			os.Exit(1)
+		}
+	}
+	fmt.Println("Everything is dandy")
+
+	time.Sleep(10 * time.Minute)
+}

pkg/framework/test/etcd.go

@@ -0,0 +1,30 @@
+package test
+
+import (
+	"os/exec"
+
+	"github.com/onsi/ginkgo"
+	"github.com/onsi/gomega/gexec"
+)
+
+// Etcd knows how to run an etcd server. Set it up with the path to a precompiled binary.
+type Etcd struct {
+	// The path to the etcd binary
+	Path string
+}
+
+// Start starts the etcd, and returns a gexec.Session. To stop it again, call Terminate and Wait on that session.
+func (s Etcd) Start(etcdURL string, datadir string) (*gexec.Session, error) {
+	args := []string{
+		"--advertise-client-urls",
+		etcdURL,
+		"--data-dir",
+		datadir,
+		"--listen-client-urls",
+		etcdURL,
+		"--debug",
+	}
+
+	command := exec.Command(s.Path, args...)
+	return gexec.Start(command, ginkgo.GinkgoWriter, ginkgo.GinkgoWriter)
+}

pkg/framework/test/etcd_test.go

@@ -0,0 +1,51 @@
+package test_test
+
+import (
+	. "k8s.io/kubectl/pkg/framework/test"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+	"github.com/onsi/gomega/gbytes"
+	"github.com/onsi/gomega/gexec"
+)
+
+var _ = Describe("Etcd", func() {
+
+	Context("when given a path to a binary that runs for a long time", func() {
+		It("can start and stop that binary", func() {
+			pathToFakeEtcd, err := gexec.Build("k8s.io/kubectl/pkg/framework/test/assets/fakeetcd")
+			Expect(err).NotTo(HaveOccurred())
+			etcd := Etcd{Path: pathToFakeEtcd}
+
+			By("Starting the Etcd Server")
+			session, err := etcd.Start("our etcd url", "our data directory")
+			Expect(err).NotTo(HaveOccurred())
+
+			Eventually(session.Out).Should(gbytes.Say("Everything is dandy"))
+			Expect(session).NotTo(gexec.Exit())
+
+			By("Stopping the Etcd Server")
+			session.Terminate()
+			Eventually(session).Should(gexec.Exit(143))
+		})
+
+	})
+
+	Context("when no path is given", func() {
+		It("fails with a helpful error", func() {
+			etcd := Etcd{}
+			_, err := etcd.Start("our etcd url", "")
+			Expect(err).To(MatchError(ContainSubstring("no such file or directory")))
+		})
+	})
+
+	Context("when given a path to a non-executable", func() {
+		It("fails with a helpful error", func() {
+			apiServer := Etcd{
+				Path: "./etcd.go",
+			}
+			_, err := apiServer.Start("our etcd url", "")
+			Expect(err).To(MatchError(ContainSubstring("./etcd.go: permission denied")))
+		})
+	})
+})