[shim] Fix DockerRunner tests (#3429)

* TestDocker_SSHServer - sshd check added
* TestDocker_SSHServerConnect - removed, as getSSHShellCommands does not
  start sshd since #3421
  The test should have failed since that PR, but, as there was no
  proper assertion, the test just slept for 180 seconds instead,
  reporting a false-positive result

Part-of: #3419

Author: un-def

runner/internal/shim/docker_test.go

@@ -5,12 +5,9 @@ import (
 	"encoding/hex"
 	"math/rand"
 	"os"
-	"os/exec"
 	"runtime"
-	"strconv"
 	"strings"
 	"sync"
-	"sync/atomic"
 	"testing"
 	"time"
 
@@ -20,90 +17,33 @@ import (
 )
 
 // TestDocker_SSHServer pulls ubuntu image (without sshd), installs openssh-server and exits
+// Basically, it indirectly tests a shell script generated by getSSHShellCommands
 func TestDocker_SSHServer(t *testing.T) {
 	if testing.Short() || (os.Getenv("CI") == "true" && runtime.GOOS == "darwin") {
 		t.Skip()
 	}
 	t.Parallel()
 
 	params := &dockerParametersMock{
-		commands:  []string{"echo 1"},
-		sshPort:   nextPort(),
-		runnerDir: t.TempDir(),
+		commands:         []string{"/usr/sbin/sshd -V 2>&1 | grep OpenSSH"},
+		sshShellCommands: true,
+		runnerDir:        t.TempDir(),
 	}
 
 	timeout := 180 // seconds
-	ctx, cancel := context.WithTimeout(context.Background(), time.Duration(timeout)*time.Second)
+	ctx, cancel := context.WithTimeout(t.Context(), time.Duration(timeout)*time.Second)
 	defer cancel()
 
 	dockerRunner, err := NewDockerRunner(ctx, params)
 	require.NoError(t, err)
 
 	taskConfig := createTaskConfig(t)
-	defer dockerRunner.Remove(context.Background(), taskConfig.ID)
+	defer dockerRunner.Remove(t.Context(), taskConfig.ID)
 
 	assert.NoError(t, dockerRunner.Submit(ctx, taskConfig))
 	assert.NoError(t, dockerRunner.Run(ctx, taskConfig.ID))
 }
 
-// TestDocker_SSHServerConnect pulls ubuntu image (without sshd), installs openssh-server and tries to connect via SSH
-func TestDocker_SSHServerConnect(t *testing.T) {
-	if testing.Short() || (os.Getenv("CI") == "true" && runtime.GOOS == "darwin") {
-		t.Skip()
-	}
-	t.Parallel()
-
-	tempDir := t.TempDir()
-	require.NoError(t, exec.CommandContext(t.Context(), "ssh-keygen", "-t", "rsa", "-b", "2048", "-f", tempDir+"/id_rsa", "-q", "-N", "").Run())
-	publicBytes, err := os.ReadFile(tempDir + "/id_rsa.pub")
-	require.NoError(t, err)
-
-	params := &dockerParametersMock{
-		commands:     []string{"sleep 5"},
-		sshPort:      nextPort(),
-		publicSSHKey: string(publicBytes),
-		runnerDir:    t.TempDir(),
-	}
-
-	timeout := 180 // seconds
-	ctx, cancel := context.WithTimeout(context.Background(), time.Duration(timeout)*time.Second)
-	defer cancel()
-
-	dockerRunner, err := NewDockerRunner(ctx, params)
-	require.NoError(t, err)
-
-	var wg sync.WaitGroup
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
-		taskConfig := createTaskConfig(t)
-		defer dockerRunner.Remove(context.Background(), taskConfig.ID)
-
-		assert.NoError(t, dockerRunner.Submit(ctx, taskConfig))
-		assert.NoError(t, dockerRunner.Run(ctx, taskConfig.ID))
-	}()
-
-	for i := 0; i < timeout; i++ {
-		cmd := exec.CommandContext(
-			t.Context(),
-			"ssh",
-			"-F", "none",
-			"-o", "StrictHostKeyChecking=no",
-			"-o", "UserKnownHostsFile=/dev/null",
-			"-i", tempDir+"/id_rsa",
-			"-p", strconv.Itoa(params.sshPort),
-			"root@localhost", "whoami",
-		)
-		output, err := cmd.Output()
-		if err == nil {
-			assert.Equal(t, "root\n", string(output))
-			break
-		}
-		time.Sleep(time.Second) // 1 attempt per second
-	}
-	wg.Wait()
-}
-
 func TestDocker_ShmNoexecByDefault(t *testing.T) {
 	if testing.Short() || (os.Getenv("CI") == "true" && runtime.GOOS == "darwin") {
 		t.Skip()
@@ -116,14 +56,14 @@ func TestDocker_ShmNoexecByDefault(t *testing.T) {
 	}
 
 	timeout := 180 // seconds
-	ctx, cancel := context.WithTimeout(context.Background(), time.Duration(timeout)*time.Second)
+	ctx, cancel := context.WithTimeout(t.Context(), time.Duration(timeout)*time.Second)
 	defer cancel()
 
 	dockerRunner, err := NewDockerRunner(ctx, params)
 	require.NoError(t, err)
 
 	taskConfig := createTaskConfig(t)
-	defer dockerRunner.Remove(context.Background(), taskConfig.ID)
+	defer dockerRunner.Remove(t.Context(), taskConfig.ID)
 
 	assert.NoError(t, dockerRunner.Submit(ctx, taskConfig))
 	assert.NoError(t, dockerRunner.Run(ctx, taskConfig.ID))
@@ -141,15 +81,15 @@ func TestDocker_ShmExecIfSizeSpecified(t *testing.T) {
 	}
 
 	timeout := 180 // seconds
-	ctx, cancel := context.WithTimeout(context.Background(), time.Duration(timeout)*time.Second)
+	ctx, cancel := context.WithTimeout(t.Context(), time.Duration(timeout)*time.Second)
 	defer cancel()
 
 	dockerRunner, err := NewDockerRunner(ctx, params)
 	require.NoError(t, err)
 
 	taskConfig := createTaskConfig(t)
 	taskConfig.ShmSize = 1024 * 1024
-	defer dockerRunner.Remove(context.Background(), taskConfig.ID)
+	defer dockerRunner.Remove(t.Context(), taskConfig.ID)
 
 	assert.NoError(t, dockerRunner.Submit(ctx, taskConfig))
 	assert.NoError(t, dockerRunner.Run(ctx, taskConfig.ID))
@@ -158,11 +98,9 @@ func TestDocker_ShmExecIfSizeSpecified(t *testing.T) {
 /* Mocks */
 
 type dockerParametersMock struct {
-	// If sshPort is not set (equals zero), sshd won't be started.
-	commands     []string
-	sshPort      int
-	publicSSHKey string
-	runnerDir    string
+	commands         []string
+	sshShellCommands bool
+	runnerDir        string
 }
 
 func (c *dockerParametersMock) DockerPrivileged() bool {
@@ -174,24 +112,17 @@ func (c *dockerParametersMock) DockerPJRTDevice() string {
 }
 
 func (c *dockerParametersMock) DockerShellCommands(publicKeys []string) []string {
-	userPublicKey := c.publicSSHKey
-	if len(publicKeys) > 0 {
-		userPublicKey = strings.Join(publicKeys, "\n")
-	}
+	userPublicKey := strings.Join(publicKeys, "\n")
 	commands := make([]string, 0)
-	if c.sshPort != 0 {
+	if c.sshShellCommands {
 		commands = append(commands, getSSHShellCommands(userPublicKey)...)
 	}
 	commands = append(commands, c.commands...)
 	return commands
 }
 
 func (c *dockerParametersMock) DockerPorts() []int {
-	ports := make([]int, 0)
-	if c.sshPort != 0 {
-		ports = append(ports, c.sshPort)
-	}
-	return ports
+	return []int{}
 }
 
 func (c *dockerParametersMock) DockerMounts(string) ([]mount.Mount, error) {
@@ -204,12 +135,6 @@ func (c *dockerParametersMock) MakeRunnerDir(string) (string, error) {
 
 /* Utilities */
 
-var portNumber int32 = 10000
-
-func nextPort() int {
-	return int(atomic.AddInt32(&portNumber, 1))
-}
-
 var (
 	randSrc = rand.New(rand.NewSource(time.Now().UnixNano()))
 	randMu  = sync.Mutex{}