socket: Add option to create backup

internal/dis/component/server/admin/socket/actions.go

@@ -0,0 +1,83 @@
+package socket
+
+import (
+	"context"
+	"io"
+
+	"github.com/FAU-CDI/wisski-distillery/internal/dis/component/exporter"
+	"github.com/FAU-CDI/wisski-distillery/internal/wisski"
+)
+
+// non-instance specific actions
+var actions = map[string]SocketAction{
+	"backup": {
+		HandleInteractive: func(ctx context.Context, socket *Sockets, out io.Writer, params ...string) error {
+			return socket.Dependencies.Exporter.MakeExport(
+				ctx,
+				out,
+				exporter.ExportTask{
+					Dest:     "",
+					Instance: nil,
+
+					StagingOnly: false,
+				},
+			)
+		},
+	},
+}
+
+// socket specific actions
+var iActions = map[string]IAction{
+	"snapshot": {
+		HandleInteractive: func(ctx context.Context, socket *Sockets, instance *wisski.WissKI, out io.Writer, params ...string) error {
+			return socket.Dependencies.Exporter.MakeExport(
+				ctx,
+				out,
+				exporter.ExportTask{
+					Dest:     "",
+					Instance: instance,
+
+					StagingOnly: false,
+				},
+			)
+		},
+	},
+	"rebuild": {
+		HandleInteractive: func(ctx context.Context, _ *Sockets, instance *wisski.WissKI, out io.Writer, params ...string) error {
+			return instance.Barrel().Build(ctx, out, true)
+		},
+	},
+	"update": {
+		HandleInteractive: func(ctx context.Context, _ *Sockets, instance *wisski.WissKI, out io.Writer, params ...string) error {
+			return instance.Drush().Update(ctx, out)
+		},
+	},
+	"cron": {
+		HandleInteractive: func(ctx context.Context, _ *Sockets, instance *wisski.WissKI, str io.Writer, params ...string) error {
+			return instance.Drush().Cron(ctx, str)
+		},
+	},
+	"start": {
+		HandleInteractive: func(ctx context.Context, _ *Sockets, instance *wisski.WissKI, out io.Writer, params ...string) error {
+			return instance.Barrel().Stack().Up(ctx, out)
+		},
+	},
+	"stop": {
+		HandleInteractive: func(ctx context.Context, _ *Sockets, instance *wisski.WissKI, out io.Writer, params ...string) error {
+			return instance.Barrel().Stack().Down(ctx, out)
+		},
+	},
+	"purge": {
+		HandleInteractive: func(ctx context.Context, sockets *Sockets, instance *wisski.WissKI, out io.Writer, params ...string) error {
+			return sockets.Dependencies.Purger.Purge(ctx, out, instance.Slug)
+		},
+	},
+}
+
+var igActions = func() map[string]SocketAction {
+	generics := make(map[string]SocketAction, len(iActions))
+	for n, a := range iActions {
+		generics[n] = a.AsGenericAction()
+	}
+	return generics
+}()

internal/dis/component/server/admin/socket/socket.go

@@ -0,0 +1,116 @@
+package socket
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"time"
+
+	"github.com/FAU-CDI/wisski-distillery/internal/dis/component"
+	"github.com/FAU-CDI/wisski-distillery/internal/dis/component/exporter"
+	"github.com/FAU-CDI/wisski-distillery/internal/dis/component/instances"
+	"github.com/FAU-CDI/wisski-distillery/internal/dis/component/instances/purger"
+	"github.com/FAU-CDI/wisski-distillery/internal/wisski"
+	"github.com/FAU-CDI/wisski-distillery/pkg/httpx"
+	"github.com/tkw1536/goprogram/status"
+)
+
+type Sockets struct {
+	component.Base
+
+	Dependencies struct {
+		Instances *instances.Instances
+		Exporter  *exporter.Exporter
+		Purger    *purger.Purger
+	}
+}
+
+// Serve handles a connection to the websocket api
+func (socket *Sockets) Serve(conn httpx.WebSocketConnection) {
+	// read the next message to act on
+	message, ok := <-conn.Read()
+	if !ok {
+		return
+	}
+
+	name := string(message.Bytes)
+
+	// perform a generic action first
+	if action, ok := actions[name]; ok {
+		socket.Handle(conn, action)
+		return
+	}
+
+	// then do the socket actions
+	if action, ok := igActions[name]; ok {
+		socket.Handle(conn, action)
+	}
+}
+
+var instanceParamsTimeout = time.Second
+
+func (socket *Sockets) Handle(conn httpx.WebSocketConnection, action SocketAction) {
+	// read the parameters
+	params := make([]string, action.NumParams)
+	for i := range params {
+		select {
+		case message, ok := <-conn.Read():
+			if !ok {
+				<-conn.WriteText("Insufficient parameters")
+				return
+			}
+			params[i] = string(message.Bytes)
+		case <-time.After(instanceParamsTimeout):
+			<-conn.WriteText("Timed out reading parameters")
+			return
+		}
+	}
+
+	// build a stream
+	writer := &status.LineBuffer{
+		Line: func(line string) {
+			<-conn.WriteText(line)
+		},
+		FlushLineOnClose: true,
+	}
+	defer writer.Close()
+
+	// handle the interactive action
+	if action.HandleInteractive != nil {
+		err := action.HandleInteractive(conn.Context(), socket, writer, params...)
+		if err != nil {
+			fmt.Fprintln(writer, err)
+			return
+		}
+		fmt.Fprintln(writer, "done")
+	}
+}
+
+// IAction is like SocketAction, but takes the slug of an instance (runnning or not) as the first parameter
+type IAction struct {
+	NumParams int
+
+	HandleInteractive func(ctx context.Context, sockets *Sockets, instance *wisski.WissKI, out io.Writer, params ...string) error
+}
+
+// AsGenericAction turns this InstanceAction into a generic action
+func (ia IAction) AsGenericAction() SocketAction {
+	return SocketAction{
+		NumParams: ia.NumParams + 1,
+		HandleInteractive: func(ctx context.Context, sockets *Sockets, out io.Writer, params ...string) error {
+			instance, err := sockets.Dependencies.Instances.WissKI(ctx, params[0])
+			if err != nil {
+				return err
+			}
+
+			return ia.HandleInteractive(ctx, sockets, instance, out, params[1:]...)
+		},
+	}
+}
+
+// SocketAction represents an action handled via socket
+type SocketAction struct {
+	NumParams int
+
+	HandleInteractive func(ctx context.Context, sockets *Sockets, out io.Writer, params ...string) error
+}