Implement 'network leave'

go/cmd/entrypoint/network.go

@@ -177,6 +177,31 @@ var subCmdNetworkJoin = subCmd{
 	},
 }
 
+var subCmdNetworkLeave = subCmd{
+	name:  "leave",
+	descr: "Leaves a network which was previously joined or created",
+	do: func(ctx subCmdCtx) error {
+		yesImSure := ctx.flags.Bool("yes-im-sure", false, "Must be given")
+
+		ctx, err := ctx.withParsedFlags(nil)
+		if err != nil {
+			return fmt.Errorf("parsing flags: %w", err)
+		}
+
+		if !*yesImSure {
+			return errors.New("--yes-im-sure must be given")
+		}
+
+		daemonRPC, err := ctx.newDaemonRPC()
+		if err != nil {
+			return fmt.Errorf("creating daemon RPC client: %w", err)
+		}
+		defer daemonRPC.Close()
+
+		return daemonRPC.LeaveNetwork(ctx)
+	},
+}
+
 var subCmdNetworkList = subCmd{
 	name:  "list",
 	descr: "Lists all networks which have been joined",
@@ -290,6 +315,7 @@ var subCmdNetwork = subCmd{
 		return ctx.doSubCmd(
 			subCmdNetworkCreate,
 			subCmdNetworkJoin,
+			subCmdNetworkLeave,
 			subCmdNetworkList,
 			subCmdNetworkGetConfig,
 		)

go/daemon/client.go

@@ -106,6 +106,15 @@ func (c *rpcClient) JoinNetwork(ctx context.Context, j1 network.JoiningBootstrap
 	return
 }
 
+func (c *rpcClient) LeaveNetwork(ctx context.Context) (err error) {
+	err = c.client.Call(
+		ctx,
+		nil,
+		"LeaveNetwork",
+	)
+	return
+}
+
 func (c *rpcClient) RemoveHost(ctx context.Context, hostName nebula.HostName) (err error) {
 	err = c.client.Call(
 		ctx,

go/daemon/daemon.go

@@ -257,6 +257,30 @@ func withNetwork[Res any](
 	return fn(ctx, network)
 }
 
+// LeaveNetwork picks the network out of the Context which was embedded by
+// WithNetwork, and leaves it. The Network will no longer be considered joined
+// and will not be active after this returns.
+//
+// Errors:
+// - ErrNoNetwork
+// - ErrNoMatchingNetworks
+// - ErrMultipleMatchingNetworks
+func (d *Daemon) LeaveNetwork(ctx context.Context) error {
+	d.l.Lock()
+	defer d.l.Unlock()
+
+	network, err := pickNetwork(ctx, d.networkLoader, d.networks)
+	if err != nil {
+		return err
+	}
+
+	shutdownErr := network.Shutdown()
+	loaderLeaveErr := d.networkLoader.Leave(ctx, network.creationParams)
+	delete(d.networks, network.creationParams.ID)
+
+	return errors.Join(shutdownErr, loaderLeaveErr)
+}
+
 // GetNetworks returns all networks which have been joined by the Daemon,
 // ordered by their name.
 func (d *Daemon) GetNetworks(
@@ -401,7 +425,13 @@ func (d *Daemon) GetConfig(
 	)
 }
 
-// SetConfig implements the method for the network.RPC interface.
+// SetConfig extends the [network.RPC] method of the same name such that
+// [ErrManagedNetworkConfig] is returned if the picked network is
+// configured as part of the [daecommon.Config] which the Daemon was
+// initialized with.
+//
+// See the `network.RPC` documentation in this interface for more usage
+// details.
 func (d *Daemon) SetConfig(
 	ctx context.Context, networkConfig daecommon.NetworkConfig,
 ) error {

go/daemon/daemon_test.go

@@ -363,6 +363,35 @@ func TestDaemon_CreateNetwork(t *testing.T) {
 	})
 }
 
+func TestDaemon_LeaveNetwork(t *testing.T) {
+	t.Run("success", func(t *testing.T) {
+		var (
+			networkA        = network.NewMockNetwork(t)
+			creationParamsA = bootstrap.NewCreationParams("AAA", "a.com")
+			h               = newHarness(t, &harnessOpts{
+				expectNetworksLoaded: []expectNetworkLoad{{
+					creationParamsA, nil, networkA,
+				}},
+				expectStoredConfigs: map[string]daecommon.NetworkConfig{
+					creationParamsA.ID: daecommon.NewNetworkConfig(nil),
+				},
+			})
+		)
+
+		h.networkLoader.
+			On("Leave", toolkit.MockArg[context.Context](), creationParamsA).
+			Return(nil).
+			Once()
+
+		ctx := WithNetwork(h.ctx, "AAA")
+		assert.NoError(t, h.daemon.LeaveNetwork(ctx))
+
+		joinedCreationParams, err := h.daemon.GetNetworks(h.ctx)
+		assert.NoError(t, err)
+		assert.Empty(t, joinedCreationParams)
+	})
+}
+
 func TestDaemon_SetConfig(t *testing.T) {
 	t.Run("success", func(t *testing.T) {
 		var (

go/daemon/network/bootstrap.go

@@ -30,6 +30,25 @@ func writeBootstrapToStateDir(
 	return nil
 }
 
+func loadBootstrapFromStateDir(
+	stateDirPath string,
+) (
+	bootstrap.Bootstrap, error,
+) {
+	var (
+		currBootstrap     bootstrap.Bootstrap
+		bootstrapFilePath = bootstrap.StateDirPath(stateDirPath)
+	)
+
+	if err := jsonutil.LoadFile(&currBootstrap, bootstrapFilePath); err != nil {
+		return bootstrap.Bootstrap{}, fmt.Errorf(
+			"loading bootstrap from %q: %w", bootstrapFilePath, err,
+		)
+	}
+
+	return currBootstrap, nil
+}
+
 func coalesceNetworkConfigAndBootstrap(
 	networkConfig daecommon.NetworkConfig, hostBootstrap bootstrap.Bootstrap,
 ) (

go/daemon/network/loader.go

@@ -12,6 +12,9 @@ import (
 	"isle/nebula"
 	"isle/toolkit"
 	"os"
+	"path/filepath"
+	"strings"
+	"time"
 
 	"dev.mediocregopher.com/mediocre-go-lib.git/mlog"
 )
@@ -132,6 +135,9 @@ type Loader interface {
 	) (
 		Network, error,
 	)
+
+	// Leave marks a previously loadable Network as being no longer loadable.
+	Leave(context.Context, bootstrap.CreationParams) error
 }
 
 // LoaderOpts are optional parameters which can be passed in when initializing a
@@ -140,7 +146,8 @@ type LoaderOpts struct {
 	// Defaults to that returned by daecommon.GetEnvVars.
 	EnvVars daecommon.EnvVars
 
-	constructors constructors // defaults to newConstructors()
+	constructors constructors     // defaults to newConstructors()
+	nowFunc      func() time.Time // defaults to time.Now
 }
 
 func (o *LoaderOpts) withDefaults() *LoaderOpts {
@@ -156,6 +163,10 @@ func (o *LoaderOpts) withDefaults() *LoaderOpts {
 		o.constructors = newConstructors()
 	}
 
+	if o.nowFunc == nil {
+		o.nowFunc = time.Now
+	}
+
 	return o
 }
 
@@ -226,6 +237,10 @@ func (l *loader) Loadable(
 	creationParams := make([]bootstrap.CreationParams, 0, len(networkStateDirs))
 
 	for _, networkStateDir := range networkStateDirs {
+		if n := filepath.Base(networkStateDir.Path); strings.HasPrefix(n, ".") {
+			continue
+		}
+
 		thisCreationParams, err := loadCreationParams(networkStateDir)
 		if err != nil {
 			return nil, fmt.Errorf(
@@ -390,3 +405,50 @@ func (l *loader) Create(
 
 	return n, nil
 }
+
+func (l *loader) Leave(
+	ctx context.Context, creationParams bootstrap.CreationParams,
+) error {
+	networkID := creationParams.ID
+
+	if isJoined, err := l.isJoined(ctx, networkID); err != nil {
+		return fmt.Errorf("checking if network is already joined: %w", err)
+	} else if !isJoined {
+		return errors.New("network is not yet joined")
+	}
+
+	networkStateDir, networkRuntimeDir, err := networkDirs(
+		l.networksStateDir, l.networksRuntimeDir, networkID, true,
+	)
+	if err != nil {
+		return fmt.Errorf(
+			"creating sub-directories for network %q: %w", networkID, err,
+		)
+	}
+
+	var (
+		newNetworkStateDirName = fmt.Sprintf(
+			".%s.%s.bak",
+			creationParams.ID,
+			l.opts.nowFunc().UTC().Format("20060102-150405"),
+		)
+		newNetworkStateDirPath = filepath.Join(
+			l.networksStateDir.Path,
+			newNetworkStateDirName,
+		)
+	)
+
+	var errs []error
+
+	if err := os.Rename(
+		networkStateDir.Path, newNetworkStateDirPath,
+	); err != nil {
+		errs = append(errs, err)
+	}
+
+	if err := os.RemoveAll(networkRuntimeDir.Path); err != nil {
+		errs = append(errs, err)
+	}
+
+	return errors.Join(errs...)
+}

go/daemon/network/loader_mock.go

@@ -80,6 +80,24 @@ func (_m *MockLoader) Join(_a0 context.Context, _a1 *mlog.Logger, _a2 JoiningBoo
 	return r0, r1
 }
 
+// Leave provides a mock function with given fields: _a0, _a1
+func (_m *MockLoader) Leave(_a0 context.Context, _a1 bootstrap.CreationParams) error {
+	ret := _m.Called(_a0, _a1)
+
+	if len(ret) == 0 {
+		panic("no return value specified for Leave")
+	}
+
+	var r0 error
+	if rf, ok := ret.Get(0).(func(context.Context, bootstrap.CreationParams) error); ok {
+		r0 = rf(_a0, _a1)
+	} else {
+		r0 = ret.Error(0)
+	}
+
+	return r0
+}
+
 // Load provides a mock function with given fields: _a0, _a1, _a2, _a3
 func (_m *MockLoader) Load(_a0 context.Context, _a1 *mlog.Logger, _a2 bootstrap.CreationParams, _a3 *Opts) (Network, error) {
 	ret := _m.Called(_a0, _a1, _a2, _a3)

go/daemon/network/loader_test.go

@@ -3,6 +3,7 @@ package network
 import (
 	"context"
 	"errors"
+	"fmt"
 	"io/fs"
 	"isle/bootstrap"
 	"isle/daemon/children"
@@ -12,6 +13,7 @@ import (
 	"os"
 	"path/filepath"
 	"testing"
+	"time"
 
 	"dev.mediocregopher.com/mediocre-go-lib.git/mlog"
 	"github.com/stretchr/testify/assert"
@@ -40,6 +42,7 @@ func newLoaderHarness(t *testing.T) *loaderHarness {
 		stateDir, _   = rootDir.MkChildDir("state", false)
 		runtimeDir, _ = rootDir.MkChildDir("runtime", false)
 		constructors  = newMockConstructors(t)
+		now           = time.Date(2024, 12, 17, 16, 15, 14, 0, time.UTC)
 	)
 
 	loader, err := NewLoader(
@@ -49,6 +52,7 @@ func newLoaderHarness(t *testing.T) *loaderHarness {
 				RuntimeDir: runtimeDir,
 			},
 			constructors: constructors,
+			nowFunc:      func() time.Time { return now },
 		},
 	)
 	require.NoError(t, err)
@@ -159,6 +163,16 @@ func TestLoader_Loadable(t *testing.T) {
 		assert.NoError(t, err)
 		assert.ElementsMatch(t, allCreationParams, got)
 	})
+
+	t.Run("after Leave", func(t *testing.T) {
+		h := newLoaderHarness(t)
+		h.join(t, allCreationParams[0])
+		h.join(t, allCreationParams[1])
+		assert.NoError(t, h.loader.Leave(h.ctx, allCreationParams[1]))
+		got, err := h.loader.Loadable(h.ctx)
+		assert.NoError(t, err)
+		assert.Equal(t, allCreationParams[:1], got)
+	})
 }
 
 func TestLoader_Load(t *testing.T) {
@@ -387,3 +401,35 @@ func TestLoader_Create(t *testing.T) {
 		h.assertDirExists(t, false, networkRuntimeDirPath)
 	})
 }
+
+func TestLoader_Leave(t *testing.T) {
+	var (
+		creationParams = bootstrap.NewCreationParams("AAA", "a.com")
+	)
+
+	t.Run("success", func(t *testing.T) {
+		var (
+			h                     = newLoaderHarness(t)
+			networkStateDirPath   = h.networkStateDirPath(creationParams.ID)
+			networkRuntimeDirPath = h.networkRuntimeDirPath(creationParams.ID)
+		)
+
+		h.join(t, creationParams)
+
+		assert.NoError(t, h.loader.Leave(h.ctx, creationParams))
+		h.assertDirExists(t, false, networkStateDirPath)
+		h.assertDirExists(t, false, networkRuntimeDirPath)
+
+		wantStateDirRenamedTo := h.networkStateDirPath(fmt.Sprintf(
+			".%s.20241217-161514.bak",
+			creationParams.ID,
+		))
+		t.Logf("wantStateDirRenamedTo:%q", wantStateDirRenamedTo)
+		h.assertDirExists(t, true, wantStateDirRenamedTo)
+
+		// Make sure the data inside the state directory was actually preserved.
+		bootstrap, err := loadBootstrapFromStateDir(wantStateDirRenamedTo)
+		assert.NoError(t, err)
+		assert.Equal(t, creationParams, bootstrap.NetworkCreationParams)
+	})
+}

go/daemon/network/network.go

@@ -288,16 +288,12 @@ func (constructorsImpl) load(
 		return nil, fmt.Errorf("instantiating Network: %w", err)
 	}
 
-	var (
-		currBootstrap     bootstrap.Bootstrap
-		bootstrapFilePath = bootstrap.StateDirPath(n.stateDir.Path)
-	)
+	currBootstrap, err := loadBootstrapFromStateDir(n.stateDir.Path)
+	if err != nil {
+		return nil, fmt.Errorf("loading bootstrap from state dir: %w", err)
+	}
 
-	if err := jsonutil.LoadFile(&currBootstrap, bootstrapFilePath); err != nil {
-		return nil, fmt.Errorf(
-			"loading bootstrap from %q: %w", bootstrapFilePath, err,
-		)
-	} else if err := n.initialize(ctx, currBootstrap, false); err != nil {
+	if err := n.initialize(ctx, currBootstrap, false); err != nil {
 		return nil, fmt.Errorf("initializing with bootstrap: %w", err)
 	}
 

go/daemon/rpc.go

@@ -43,15 +43,10 @@ type RPC interface {
 
 	JoinNetwork(context.Context, network.JoiningBootstrap) error
 
+	LeaveNetwork(context.Context) error
+
 	GetNetworks(context.Context) ([]bootstrap.CreationParams, error)
 
-	// SetConfig extends the [network.RPC] method of the same name such that
-	// [ErrManagedNetworkConfig] is returned if the picked network is
-	// configured as part of the [daecommon.Config] which the Daemon was
-	// initialized with.
-	//
-	// See the `network.RPC` documentation in this interface for more usage
-	// details.
 	SetConfig(context.Context, daecommon.NetworkConfig) error
 
 	// All network.RPC methods are automatically implemented by Daemon using the

go/daemon/rpc_mock.go

@@ -226,6 +226,24 @@ func (_m *MockRPC) JoinNetwork(_a0 context.Context, _a1 network.JoiningBootstrap
 	return r0
 }
 
+// LeaveNetwork provides a mock function with given fields: _a0
+func (_m *MockRPC) LeaveNetwork(_a0 context.Context) error {
+	ret := _m.Called(_a0)
+
+	if len(ret) == 0 {
+		panic("no return value specified for LeaveNetwork")
+	}
+
+	var r0 error
+	if rf, ok := ret.Get(0).(func(context.Context) error); ok {
+		r0 = rf(_a0)
+	} else {
+		r0 = ret.Error(0)
+	}
+
+	return r0
+}
+
 // RemoveHost provides a mock function with given fields: ctx, hostName
 func (_m *MockRPC) RemoveHost(ctx context.Context, hostName nebula.HostName) error {
 	ret := _m.Called(ctx, hostName)

tasks/v0.0.3/network-leave.md

@@ -1,8 +0,0 @@
----
-type: task
----
-
-# Implement `network leave` sub-command
-
-When leaving a network the daemon should remove the now-defunct state-directory,
-or at least mark it as inactive in some way.