banger/internal/firecracker/client_test.go

package firecracker

import (
	"bytes"
	"log/slog"
	"strings"
	"testing"
)

func TestBuildConfig(t *testing.T) {
	cfg := buildConfig(MachineConfig{
		VMID:            "vm-1",
		SocketPath:      "/tmp/fc.sock",
		LogPath:         "/tmp/fc.log",
		MetricsPath:     "/tmp/fc.metrics",
		KernelImagePath: "/kernel",
		InitrdPath:      "/initrd",
		KernelArgs:      "console=ttyS0",
		Drives: []DriveConfig{
			{ID: "rootfs", Path: "/dev/mapper/root", IsRoot: true},
			{ID: "work", Path: "/var/lib/banger/root.ext4"},
		},
		TapDevice: "tap-fc-1",
		VCPUCount: 4,
		MemoryMiB: 2048,
	})

	if cfg.SocketPath != "/tmp/fc.sock" {
		t.Fatalf("socket path = %q", cfg.SocketPath)
	}
	if cfg.LogPath != "/tmp/fc.log" || cfg.MetricsPath != "/tmp/fc.metrics" {
		t.Fatalf("unexpected log or metrics path: %+v", cfg)
	}
	if cfg.KernelImagePath != "/kernel" || cfg.InitrdPath != "/initrd" {
		t.Fatalf("unexpected kernel paths: %+v", cfg)
	}
	if len(cfg.Drives) != 2 {
		t.Fatalf("drive count = %d, want 2", len(cfg.Drives))
	}
	if cfg.Drives[0].DriveID == nil || *cfg.Drives[0].DriveID != "work" {
		t.Fatalf("work drive id = %v", cfg.Drives[0].DriveID)
	}
	if cfg.Drives[1].DriveID == nil || *cfg.Drives[1].DriveID != "rootfs" {
		t.Fatalf("root drive id = %v", cfg.Drives[1].DriveID)
	}
	if len(cfg.NetworkInterfaces) != 1 {
		t.Fatalf("interface count = %d, want 1", len(cfg.NetworkInterfaces))
	}
	if got := cfg.NetworkInterfaces[0].StaticConfiguration.HostDevName; got != "tap-fc-1" {
		t.Fatalf("host dev name = %q", got)
	}
	if cfg.MachineCfg.VcpuCount == nil || *cfg.MachineCfg.VcpuCount != 4 {
		t.Fatalf("vcpu = %v", cfg.MachineCfg.VcpuCount)
	}
	if cfg.MachineCfg.MemSizeMib == nil || *cfg.MachineCfg.MemSizeMib != 2048 {
		t.Fatalf("memory = %v", cfg.MachineCfg.MemSizeMib)
	}
	if cfg.MachineCfg.Smt == nil || *cfg.MachineCfg.Smt {
		t.Fatalf("smt = %v, want false", cfg.MachineCfg.Smt)
	}
}

func TestBuildProcessRunnerUsesSudoShellWrapper(t *testing.T) {
	cmd := buildProcessRunner(MachineConfig{
		BinaryPath: "/repo/firecracker",
		SocketPath: "/tmp/fc.sock",
		VMID:       "vm-1",
	}, nil)

	if cmd.Path != "/usr/bin/sudo" && cmd.Path != "sudo" {
		t.Fatalf("command path = %q", cmd.Path)
	}
	if len(cmd.Args) != 5 {
		t.Fatalf("args = %v", cmd.Args)
	}
	if cmd.Args[1] != "-n" || cmd.Args[2] != "sh" || cmd.Args[3] != "-c" {
		t.Fatalf("args = %v", cmd.Args)
	}
	want := "umask 000 && exec '/repo/firecracker' --api-sock '/tmp/fc.sock' --id 'vm-1'"
	if cmd.Args[4] != want {
		t.Fatalf("script = %q, want %q", cmd.Args[4], want)
	}
	if cmd.Cancel != nil {
		t.Fatal("process runner should not be tied to a request context")
	}
}

func TestSDKLoggerBridgeEmitsStructuredDebugLogs(t *testing.T) {
	var buf bytes.Buffer
	logger := slog.New(slog.NewJSONHandler(&buf, &slog.HandlerOptions{Level: slog.LevelDebug}))

	entry := newLogger(logger)
	entry.WithField("vm_id", "vm-1").Info("sdk ready")

	output := buf.String()
	if !strings.Contains(output, `"component":"firecracker_sdk"`) {
		t.Fatalf("output = %q, want firecracker_sdk component", output)
	}
	if !strings.Contains(output, `"vm_id":"vm-1"`) {
		t.Fatalf("output = %q, want vm_id field", output)
	}
	if !strings.Contains(output, `"msg":"sdk ready"`) {
		t.Fatalf("output = %q, want sdk message", output)
	}
}

func TestSDKLoggerBridgeSuppressesDebugAtInfoLevel(t *testing.T) {
	var buf bytes.Buffer
	logger := slog.New(slog.NewJSONHandler(&buf, &slog.HandlerOptions{Level: slog.LevelInfo}))

	entry := newLogger(logger)
	entry.Info("sdk hidden at info")

	if buf.Len() != 0 {
		t.Fatalf("expected info-level logger to suppress sdk debug chatter, got %q", buf.String())
	}
}