dhcpsvc: add tests

internal/dhcpsvc/config_test.go

@@ -121,7 +121,7 @@ func TestConfig_Validate(t *testing.T) {
 	}, {
 		conf: &dhcpsvc.Config{
 			Enabled:         true,
-			Logger:          discardLog,
+			Logger:          testLogger,
 			LocalDomainName: testLocalTLD,
 			Interfaces: map[string]*dhcpsvc.InterfaceConfig{
 				"eth0": {
@@ -136,7 +136,7 @@ func TestConfig_Validate(t *testing.T) {
 	}, {
 		conf: &dhcpsvc.Config{
 			Enabled:         true,
-			Logger:          discardLog,
+			Logger:          testLogger,
 			LocalDomainName: testLocalTLD,
 			Interfaces: map[string]*dhcpsvc.InterfaceConfig{
 				"eth0": {
@@ -151,7 +151,7 @@ func TestConfig_Validate(t *testing.T) {
 	}, {
 		conf: &dhcpsvc.Config{
 			Enabled:         true,
-			Logger:          discardLog,
+			Logger:          testLogger,
 			LocalDomainName: testLocalTLD,
 			Interfaces: map[string]*dhcpsvc.InterfaceConfig{
 				"eth0": {
@@ -167,7 +167,7 @@ func TestConfig_Validate(t *testing.T) {
 	}, {
 		conf: &dhcpsvc.Config{
 			Enabled:         true,
-			Logger:          discardLog,
+			Logger:          testLogger,
 			LocalDomainName: testLocalTLD,
 			Interfaces: map[string]*dhcpsvc.InterfaceConfig{
 				"eth0": {

internal/dhcpsvc/dhcpsvc_test.go

@@ -1,12 +1,20 @@
 package dhcpsvc_test
 
 import (
+	"cmp"
+	"io/fs"
 	"net/netip"
+	"os"
+	"path"
+	"path/filepath"
+	"testing"
 	"time"
 
 	"github.com/AdguardTeam/AdGuardHome/internal/dhcpsvc"
 	"github.com/AdguardTeam/golibs/logutil/slogutil"
+	"github.com/AdguardTeam/golibs/testutil"
 	"github.com/AdguardTeam/golibs/timeutil"
+	"github.com/stretchr/testify/require"
 )
 
 // testLocalTLD is a common local TLD for tests.
@@ -15,8 +23,11 @@ const testLocalTLD = "local"
 // testTimeout is a common timeout for tests and contexts.
 const testTimeout time.Duration = 10 * time.Second
 
-// discardLog is a logger to discard test output.
-var discardLog = slogutil.NewDiscardLogger()
+// testLogger is a common logger for tests.
+var testLogger = slogutil.NewDiscardLogger()
+
+// testdata is a filesystem containing data for tests.
+var testdata = os.DirFS("testdata")
 
 // testInterfaceConf is a common set of interface configurations for tests.
 var testInterfaceConf = map[string]*dhcpsvc.InterfaceConfig{
@@ -57,3 +68,50 @@ var testInterfaceConf = map[string]*dhcpsvc.InterfaceConfig{
 		},
 	},
 }
+
+// newTempDB copies the leases database file located in the testdata FS, under
+// tb.Name()/leases.json, to a temporary directory and returns the path to the
+// copied file.
+func newTempDB(tb testing.TB) (dst string) {
+	tb.Helper()
+
+	const filename = "leases.json"
+
+	data, err := fs.ReadFile(testdata, path.Join(tb.Name(), filename))
+	require.NoError(tb, err)
+
+	dst = filepath.Join(tb.TempDir(), filename)
+
+	err = os.WriteFile(dst, data, dhcpsvc.DatabasePerm)
+	require.NoError(tb, err)
+
+	return dst
+}
+
+// newTestDHCPServer creates a new DHCPServer for testing.  It uses the default
+// values of config in case it's nil or some of its fields aren't set.
+func newTestDHCPServer(t *testing.T, conf *dhcpsvc.Config) (srv *dhcpsvc.DHCPServer) {
+	t.Helper()
+
+	conf = cmp.Or(conf, &dhcpsvc.Config{
+		Enabled: true,
+	})
+	if conf.Interfaces == nil {
+		conf.Interfaces = testInterfaceConf
+	}
+	conf.NetworkDeviceManager = cmp.Or[dhcpsvc.NetworkDeviceManager](
+		conf.NetworkDeviceManager,
+		dhcpsvc.EmptyNetworkDeviceManager{},
+	)
+	conf.Logger = cmp.Or(conf.Logger, testLogger)
+	conf.LocalDomainName = cmp.Or(conf.LocalDomainName, testLocalTLD)
+	if conf.DBFilePath == "" {
+		conf.DBFilePath = filepath.Join(t.TempDir(), "leases.json")
+	}
+	conf.ICMPTimeout = cmp.Or(conf.ICMPTimeout, testTimeout)
+
+	srv, err := dhcpsvc.New(testutil.ContextWithTimeout(t, testTimeout), conf)
+	require.NoError(t, err)
+
+	return srv
+}

internal/dhcpsvc/handler4_test.go

@@ -0,0 +1,41 @@
+package dhcpsvc_test
+
+import (
+	"context"
+	"testing"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/dhcpsvc"
+	"github.com/AdguardTeam/golibs/testutil/servicetest"
+)
+
+func TestDHCPServer_ServeEther4(t *testing.T) {
+	t.Parallel()
+
+	ndMgr := &testNetworkDeviceManager{
+		onOpen: func(
+			ctx context.Context,
+			conf *dhcpsvc.NetworkDeviceConfig,
+		) (nd dhcpsvc.NetworkDevice, err error) {
+			return &testNetworkDevice{
+				// TODO(e.burkov):  !! implement ReadPacketData, WritePacketData, and LinkType
+			}, nil
+		},
+	}
+
+	srv := newTestDHCPServer(t, &dhcpsvc.Config{
+		NetworkDeviceManager: ndMgr,
+		Enabled:              true,
+	})
+	servicetest.RequireRun(t, srv, testTimeout)
+
+	testCases := []struct {
+		name string
+		// TODO(e.burkov):  !! define other fields.
+	}{}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			// TODO(e.burkov):  !! implement a test
+		})
+	}
+}

internal/dhcpsvc/networkdevice.go

@@ -34,6 +34,22 @@ type NetworkDeviceManager interface {
 	Open(ctx context.Context, conf *NetworkDeviceConfig) (dev NetworkDevice, err error)
 }
 
+// EmptyNetworkDeviceManager is an empty implementation of
+// [NetworkDeviceManager].
+type EmptyNetworkDeviceManager struct{}
+
+// type check
+var _ NetworkDeviceManager = EmptyNetworkDeviceManager{}
+
+// Open implements the [NetworkDeviceManager] interface for
+// [EmptyNetworkDeviceManager].  It always returns [EmptyNetworkDevice].
+func (EmptyNetworkDeviceManager) Open(
+	_ context.Context,
+	_ *NetworkDeviceConfig,
+) (nd NetworkDevice, err error) {
+	return nil, nil
+}
+
 // NetworkDevice provides reading and writing packets to a network interface.
 type NetworkDevice interface {
 	gopacket.PacketDataSource
@@ -45,6 +61,31 @@ type NetworkDevice interface {
 	WritePacketData(data []byte) (err error)
 }
 
+// EmptyNetworkDevice is an empty implementation of NetworkDevice.
+type EmptyNetworkDevice struct{}
+
+// type check
+var _ NetworkDevice = EmptyNetworkDevice{}
+
+// ReadPacketData implements the [gopacket.PacketDataSource] interface for
+// [EmptyNetworkDevice].  It always returns no data, empty capture info and a
+// nil error.
+func (EmptyNetworkDevice) ReadPacketData() (data []byte, ci gopacket.CaptureInfo, err error) {
+	return nil, gopacket.CaptureInfo{}, nil
+}
+
+// LinkType implements the [NetworkDevice] interface for [EmptyNetworkDevice].
+// It always returns [layers.LinkTypeNull].
+func (EmptyNetworkDevice) LinkType() (lt layers.LinkType) {
+	return layers.LinkTypeNull
+}
+
+// WritePacketData implements the [NetworkDevice] interface for
+// [EmptyNetworkDevice].  It always returns nil.
+func (EmptyNetworkDevice) WritePacketData(_ []byte) (err error) {
+	return nil
+}
+
 // frameData stores the Ethernet and IPv4 layers of the incoming packet, and
 // the network device that the packet was received from.
 type frameData struct {

internal/dhcpsvc/networkdevice_test.go

@@ -0,0 +1,57 @@
+package dhcpsvc_test
+
+import (
+	"context"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/dhcpsvc"
+	"github.com/google/gopacket"
+	"github.com/google/gopacket/layers"
+)
+
+// testNetworkDeviceManager is a mock implementation of the
+// [dhcpsvc.NetworkDeviceManager] interface.
+//
+// TODO(e.burkov):  Move to aghtest.
+type testNetworkDeviceManager struct {
+	onOpen func(
+		ctx context.Context,
+		conf *dhcpsvc.NetworkDeviceConfig,
+	) (nd dhcpsvc.NetworkDevice, err error)
+}
+
+// Open implements the [NetworkDeviceManager] interface for
+// *testNetworkDeviceManager.
+func (ndm *testNetworkDeviceManager) Open(
+	ctx context.Context,
+	conf *dhcpsvc.NetworkDeviceConfig,
+) (dev dhcpsvc.NetworkDevice, err error) {
+	return ndm.onOpen(ctx, conf)
+}
+
+// testNetworkDevice is a mock implementation of the [dhcpsvc.NetworkDevice]
+// interface.
+//
+// TODO(e.burkov):  Move to aghtest.
+type testNetworkDevice struct {
+	onReadPacketData  func() (data []byte, ci gopacket.CaptureInfo, err error)
+	onLinkType        func() (lt layers.LinkType)
+	onWritePacketData func(data []byte) (err error)
+}
+
+// ReadPacketData implements the [dhcpsvc.NetworkDevice] interface for
+// *testNetworkDevice.
+func (nd *testNetworkDevice) ReadPacketData() (data []byte, ci gopacket.CaptureInfo, err error) {
+	return nd.onReadPacketData()
+}
+
+// WritePacketData implements the [dhcpsvc.NetworkDevice] interface for
+// *testNetworkDevice.
+func (nd *testNetworkDevice) WritePacketData(data []byte) (err error) {
+	return nd.onWritePacketData(data)
+}
+
+// LinkType implements the [dhcpsvc.NetworkDevice] interface for
+// *testNetworkDevice.
+func (nd *testNetworkDevice) LinkType() (lt layers.LinkType) {
+	return nd.onLinkType()
+}

internal/dhcpsvc/server_test.go

@@ -1,11 +1,8 @@
 package dhcpsvc_test
 
 import (
-	"io/fs"
 	"net"
 	"net/netip"
-	"os"
-	"path"
 	"path/filepath"
 	"strings"
 	"testing"
@@ -18,40 +15,12 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-// testdata is a filesystem containing data for tests.
-var testdata = os.DirFS("testdata")
-
-// newTempDB copies the leases database file located in the testdata FS, under
-// tb.Name()/leases.json, to a temporary directory and returns the path to the
-// copied file.
-func newTempDB(tb testing.TB) (dst string) {
-	tb.Helper()
-
-	const filename = "leases.json"
-
-	data, err := fs.ReadFile(testdata, path.Join(tb.Name(), filename))
-	require.NoError(tb, err)
-
-	dst = filepath.Join(tb.TempDir(), filename)
-
-	err = os.WriteFile(dst, data, dhcpsvc.DatabasePerm)
-	require.NoError(tb, err)
-
-	return dst
-}
-
 func TestDHCPServer_AddLease(t *testing.T) {
-	ctx := testutil.ContextWithTimeout(t, testTimeout)
-
 	leasesPath := filepath.Join(t.TempDir(), "leases.json")
-	srv, err := dhcpsvc.New(ctx, &dhcpsvc.Config{
-		Enabled:         true,
-		Logger:          discardLog,
-		LocalDomainName: testLocalTLD,
-		Interfaces:      testInterfaceConf,
-		DBFilePath:      leasesPath,
+	srv := newTestDHCPServer(t, &dhcpsvc.Config{
+		DBFilePath: leasesPath,
+		Enabled:    true,
 	})
-	require.NoError(t, err)
 
 	const (
 		existHost = "host1"
@@ -69,6 +38,7 @@ func TestDHCPServer_AddLease(t *testing.T) {
 		ipv6MAC  = errors.Must(net.ParseMAC("02:03:04:05:06:07"))
 	)
 
+	ctx := testutil.ContextWithTimeout(t, testTimeout)
 	require.NoError(t, srv.AddLease(ctx, &dhcpsvc.Lease{
 		Hostname: existHost,
 		IP:       existIP,
@@ -144,6 +114,7 @@ func TestDHCPServer_AddLease(t *testing.T) {
 
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
+			ctx = testutil.ContextWithTimeout(t, testTimeout)
 			testutil.AssertErrorMsg(t, tc.wantErrMsg, srv.AddLease(ctx, tc.lease))
 		})
 	}
@@ -153,17 +124,11 @@ func TestDHCPServer_AddLease(t *testing.T) {
 }
 
 func TestDHCPServer_index(t *testing.T) {
-	ctx := testutil.ContextWithTimeout(t, testTimeout)
-
 	leasesPath := newTempDB(t)
-	srv, err := dhcpsvc.New(ctx, &dhcpsvc.Config{
-		Enabled:         true,
-		Logger:          discardLog,
-		LocalDomainName: testLocalTLD,
-		Interfaces:      testInterfaceConf,
-		DBFilePath:      leasesPath,
+	srv := newTestDHCPServer(t, &dhcpsvc.Config{
+		DBFilePath: leasesPath,
+		Enabled:    true,
 	})
-	require.NoError(t, err)
 
 	const (
 		host1 = "host1"
@@ -210,17 +175,11 @@ func TestDHCPServer_index(t *testing.T) {
 }
 
 func TestDHCPServer_UpdateStaticLease(t *testing.T) {
-	ctx := testutil.ContextWithTimeout(t, testTimeout)
-
 	leasesPath := newTempDB(t)
-	srv, err := dhcpsvc.New(ctx, &dhcpsvc.Config{
-		Enabled:         true,
-		Logger:          discardLog,
-		LocalDomainName: testLocalTLD,
-		Interfaces:      testInterfaceConf,
-		DBFilePath:      leasesPath,
+	srv := newTestDHCPServer(t, &dhcpsvc.Config{
+		DBFilePath: leasesPath,
+		Enabled:    true,
 	})
-	require.NoError(t, err)
 
 	const (
 		host1 = "host1"
@@ -309,6 +268,7 @@ func TestDHCPServer_UpdateStaticLease(t *testing.T) {
 
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
+			ctx := testutil.ContextWithTimeout(t, testTimeout)
 			testutil.AssertErrorMsg(t, tc.wantErrMsg, srv.UpdateStaticLease(ctx, tc.lease))
 		})
 	}
@@ -317,17 +277,11 @@ func TestDHCPServer_UpdateStaticLease(t *testing.T) {
 }
 
 func TestDHCPServer_RemoveLease(t *testing.T) {
-	ctx := testutil.ContextWithTimeout(t, testTimeout)
-
 	leasesPath := newTempDB(t)
-	srv, err := dhcpsvc.New(ctx, &dhcpsvc.Config{
-		Enabled:         true,
-		Logger:          discardLog,
-		LocalDomainName: testLocalTLD,
-		Interfaces:      testInterfaceConf,
-		DBFilePath:      leasesPath,
+	srv := newTestDHCPServer(t, &dhcpsvc.Config{
+		DBFilePath: leasesPath,
+		Enabled:    true,
 	})
-	require.NoError(t, err)
 
 	const (
 		host1 = "host1"
@@ -393,6 +347,7 @@ func TestDHCPServer_RemoveLease(t *testing.T) {
 
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
+			ctx := testutil.ContextWithTimeout(t, testTimeout)
 			testutil.AssertErrorMsg(t, tc.wantErrMsg, srv.RemoveLease(ctx, tc.lease))
 		})
 	}
@@ -403,22 +358,16 @@ func TestDHCPServer_RemoveLease(t *testing.T) {
 
 func TestDHCPServer_Reset(t *testing.T) {
 	leasesPath := newTempDB(t)
-	conf := &dhcpsvc.Config{
-		Enabled:         true,
-		Logger:          discardLog,
-		LocalDomainName: testLocalTLD,
-		Interfaces:      testInterfaceConf,
-		DBFilePath:      leasesPath,
-	}
-
-	ctx := testutil.ContextWithTimeout(t, testTimeout)
-	srv, err := dhcpsvc.New(ctx, conf)
-	require.NoError(t, err)
+	srv := newTestDHCPServer(t, &dhcpsvc.Config{
+		DBFilePath: leasesPath,
+		Enabled:    true,
+	})
 
 	const leasesNum = 4
 
 	require.Len(t, srv.Leases(), leasesNum)
 
+	ctx := testutil.ContextWithTimeout(t, testTimeout)
 	require.NoError(t, srv.Reset(ctx))
 
 	assert.FileExists(t, leasesPath)
@@ -427,18 +376,10 @@ func TestDHCPServer_Reset(t *testing.T) {
 
 func TestServer_Leases(t *testing.T) {
 	leasesPath := newTempDB(t)
-	conf := &dhcpsvc.Config{
-		Enabled:         true,
-		Logger:          discardLog,
-		LocalDomainName: testLocalTLD,
-		Interfaces:      testInterfaceConf,
-		DBFilePath:      leasesPath,
-	}
-
-	ctx := testutil.ContextWithTimeout(t, testTimeout)
-
-	srv, err := dhcpsvc.New(ctx, conf)
-	require.NoError(t, err)
+	srv := newTestDHCPServer(t, &dhcpsvc.Config{
+		DBFilePath: leasesPath,
+		Enabled:    true,
+	})
 
 	expiry, err := time.Parse(time.RFC3339, "2042-01-02T03:04:05Z")
 	require.NoError(t, err)