functional: support running etcdctl, as well as using Cluster.Keyspace

Introduce new helpers for running etcdctl for functional tests.
Also export a method Cluster.Keyspace() to get it called by functional
tests.

build-env

@@ -24,3 +24,4 @@ export PATH="${GOROOT}/bin:${PATH}"
 export FLEETD_BIN="${CDIR}/bin/fleetd"
 export FLEETCTL_BIN="${CDIR}/bin/fleetctl"
 export FLEETD_TEST_ENV="enable_grpc=false"
+export ETCDCTL_BIN="/usr/bin/etcdctl"

functional/platform/cluster.go

@@ -42,6 +42,8 @@ type Cluster interface {
 	WaitForNActiveUnits(Member, int) (map[string][]util.UnitState, error)
 	WaitForNUnitFiles(Member, int) (map[string][]util.UnitFileState, error)
 	WaitForNMachines(Member, int) ([]string, error)
+
+	Keyspace() string
 }
 
 func CreateNClusterMembers(cl Cluster, count int) ([]Member, error) {

functional/platform/nspawn.go

@@ -100,7 +100,7 @@ func (nc *nspawnCluster) nextID() string {
 	return strconv.Itoa(nc.maxID)
 }
 
-func (nc *nspawnCluster) keyspace() string {
+func (nc *nspawnCluster) Keyspace() string {
 	// TODO(jonboulle): generate this dynamically with atomic in order keys?
 	return fmt.Sprintf("/fleet_functional/%s", nc.name)
 }
@@ -367,7 +367,7 @@ func (nc *nspawnCluster) buildConfigDrive(dir, ip string) error {
 	defer userFile.Close()
 
 	etcd := "http://172.18.0.1:4001"
-	return util.BuildCloudConfig(userFile, ip, etcd, nc.keyspace())
+	return util.BuildCloudConfig(userFile, ip, etcd, nc.Keyspace())
 }
 
 func (nc *nspawnCluster) Members() []Member {
@@ -601,7 +601,7 @@ func (nc *nspawnCluster) Destroy(t *testing.T) error {
 	// TODO(bcwaldon): This returns 4 on success, but we can't easily
 	// ignore just that return code. Ignore the returned error
 	// altogether until this is fixed.
-	run("etcdctl rm --recursive " + nc.keyspace())
+	run("etcdctl rm --recursive " + nc.Keyspace())
 
 	run("ip link del fleet0")
 

functional/util/util.go

@@ -28,6 +28,7 @@ import (
 )
 
 var fleetctlBinPath string
+var etcdctlBinPath string
 
 func init() {
 	fleetctlBinPath = os.Getenv("FLEETCTL_BIN")
@@ -39,6 +40,15 @@ func init() {
 		os.Exit(1)
 	}
 
+	etcdctlBinPath = os.Getenv("ETCDCTL_BIN")
+	if etcdctlBinPath == "" {
+		fmt.Println("ETCDCTL_BIN environment variable must be set")
+		os.Exit(1)
+	} else if _, err := os.Stat(etcdctlBinPath); err != nil {
+		fmt.Printf("%v\n", err)
+		os.Exit(1)
+	}
+
 	if os.Getenv("SSH_AUTH_SOCK") == "" {
 		fmt.Println("SSH_AUTH_SOCK environment variable must be set")
 		os.Exit(1)
@@ -79,6 +89,38 @@ func RunFleetctlWithInput(input string, args ...string) (string, string, error)
 	return stdoutBytes.String(), stderrBytes.String(), err
 }
 
+func RunEtcdctl(args ...string) (string, string, error) {
+	log.Printf("%s %s", etcdctlBinPath, strings.Join(args, " "))
+	var stdoutBytes, stderrBytes bytes.Buffer
+	cmd := exec.Command(etcdctlBinPath, args...)
+	cmd.Stdout = &stdoutBytes
+	cmd.Stderr = &stderrBytes
+	err := cmd.Run()
+	return stdoutBytes.String(), stderrBytes.String(), err
+}
+
+func RunEtcdctlWithInput(input string, args ...string) (string, string, error) {
+	log.Printf("%s %s", etcdctlBinPath, strings.Join(args, " "))
+	var stdoutBytes, stderrBytes bytes.Buffer
+	cmd := exec.Command(etcdctlBinPath, args...)
+	cmd.Stdout = &stdoutBytes
+	cmd.Stderr = &stderrBytes
+	stdin, err := cmd.StdinPipe()
+	if err != nil {
+		return "", "", err
+	}
+
+	if err = cmd.Start(); err != nil {
+		return "", "", err
+	}
+
+	stdin.Write([]byte(input))
+	stdin.Close()
+	err = cmd.Wait()
+
+	return stdoutBytes.String(), stderrBytes.String(), err
+}
+
 // ActiveToSingleStates takes a map of active states (such as that returned by
 // WaitForNActiveUnits) and ensures that each unit has at most a single active
 // state. It returns a mapping of unit name to a single UnitState.