socket: Explicitly communicate success

This commit updates the socket process to explicitly communicate the
process (and any potential error) on the server using a binary message.

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

@@ -2,7 +2,8 @@ package socket
 
 import (
 	"context"
-	"fmt"
+	"encoding/json"
+	"errors"
 	"io"
 	"time"
 
@@ -12,6 +13,7 @@ import (
 	"github.com/FAU-CDI/wisski-distillery/internal/dis/component/instances/purger"
 	"github.com/FAU-CDI/wisski-distillery/internal/dis/component/provision"
 	"github.com/FAU-CDI/wisski-distillery/internal/wisski"
+	"github.com/gorilla/websocket"
 	"github.com/tkw1536/goprogram/status"
 	"github.com/tkw1536/pkglib/httpx"
 )
@@ -51,20 +53,52 @@ func (socket *Sockets) Serve(conn httpx.WebSocketConnection) {
 
 var instanceParamsTimeout = time.Second
 
-func (socket *Sockets) Handle(conn httpx.WebSocketConnection, action SocketAction) {
+type actionResult struct {
+	Success bool   `json:"success"`
+	Error   string `json:"error,omitempty"`
+}
+
+func (*Sockets) reportErrorToClient(conn httpx.WebSocketConnection, err error) {
+	// create an action result
+	var result actionResult
+	if err == nil {
+		result.Success = true
+	} else {
+		result.Success = false
+		result.Error = err.Error()
+	}
+
+	// marshal the result, ignoring any error silently
+	data, err := json.Marshal(result)
+	if err != nil {
+		return
+	}
+
+	// and send it as a binary message to the client
+	<-conn.Write(httpx.WebSocketMessage{Type: websocket.BinaryMessage, Bytes: data})
+}
+
+var errInsufficientParams = errors.New("insufficient parameters")
+var errParameterTimeout = errors.New("timed out reading parameters")
+
+func (socket *Sockets) Handle(conn httpx.WebSocketConnection, action SocketAction) (err error) {
+	// report the error to the client
+	defer func() {
+		// NOTE: the closure is needed here!
+		socket.reportErrorToClient(conn, err)
+	}()
+
 	// 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
+				return errInsufficientParams
 			}
 			params[i] = string(message.Bytes)
 		case <-time.After(instanceParamsTimeout):
-			<-conn.WriteText("Timed out reading parameters")
-			return
+			return errParameterTimeout
 		}
 	}
 
@@ -78,14 +112,7 @@ func (socket *Sockets) Handle(conn httpx.WebSocketConnection, action SocketActio
 	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")
-	}
+	return action.HandleInteractive(conn.Context(), socket, writer, params...)
 }
 
 // IAction is like SocketAction, but takes the slug of an instance (runnning or not) as the first parameter

internal/dis/component/server/assets/assets_disclaimer.txt

@@ -317,6 +317,32 @@ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLI
 
 -----
 
+The following software may be included in this product: async-mutex. A copy of the source code may be downloaded from https://github.com/DirtyHairy/async-mutex. This software contains the following license and notice below:
+
+The MIT License (MIT)
+
+Copyright (c) 2016 Christian Speckner <cnspeckn@googlemail.com>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+
+-----
+
 The following software may be included in this product: base-x. A copy of the source code may be downloaded from https://github.com/cryptocoinjs/base-x.git. This software contains the following license and notice below:
 
 The MIT License (MIT)

internal/dis/component/server/assets/assets_dist.go

@@ -24,12 +24,12 @@ var AssetsUser = Assets{
 
 // AssetsAdmin contains assets for the 'Admin' entrypoint.
 var AssetsAdmin = Assets{
-	Scripts: `<script nomodule="" defer src="/this-is-fine/User.b2f9a57c.js"></script><script type="module" src="/this-is-fine/User.e0367d79.js"></script><script type="module" src="/this-is-fine/Default.38d394c2.js"></script><script src="/this-is-fine/Default.38d394c2.js" nomodule="" defer></script><script type="module" src="/this-is-fine/Admin.620228db.js"></script><script src="/this-is-fine/Admin.939dcd95.js" nomodule="" defer></script>`,
+	Scripts: `<script nomodule="" defer src="/this-is-fine/User.b2f9a57c.js"></script><script type="module" src="/this-is-fine/User.e0367d79.js"></script><script type="module" src="/this-is-fine/Default.38d394c2.js"></script><script src="/this-is-fine/Default.38d394c2.js" nomodule="" defer></script><script type="module" src="/this-is-fine/Admin.15462d3d.js"></script><script src="/this-is-fine/Admin.2889b18a.js" nomodule="" defer></script>`,
 	Styles:  `<link rel="stylesheet" href="/this-is-fine/Default.938b4407.css"><link rel="stylesheet" href="/this-is-fine/Admin.a1e05c23.css"><link rel="stylesheet" href="/this-is-fine/User.840de3b4.css"><link rel="stylesheet" href="/this-is-fine/User.68febbf8.css"><link rel="stylesheet" href="/this-is-fine/Admin.6d2ae968.css">`,	
 }
 
 // AssetsAdminProvision contains assets for the 'AdminProvision' entrypoint.
 var AssetsAdminProvision = Assets{
-	Scripts: `<script nomodule="" defer src="/this-is-fine/User.b2f9a57c.js"></script><script nomodule="" defer src="/this-is-fine/Admin.939dcd95.js"></script><script type="module" src="/this-is-fine/User.e0367d79.js"></script><script type="module" src="/this-is-fine/Admin.620228db.js"></script><script type="module" src="/this-is-fine/Default.38d394c2.js"></script><script src="/this-is-fine/Default.38d394c2.js" nomodule="" defer></script><script type="module" src="/this-is-fine/AdminProvision.3cf9e19e.js"></script><script src="/this-is-fine/AdminProvision.d195fd59.js" nomodule="" defer></script>`,
+	Scripts: `<script nomodule="" defer src="/this-is-fine/User.b2f9a57c.js"></script><script nomodule="" defer src="/this-is-fine/Admin.2889b18a.js"></script><script type="module" src="/this-is-fine/User.e0367d79.js"></script><script type="module" src="/this-is-fine/Admin.15462d3d.js"></script><script type="module" src="/this-is-fine/Default.38d394c2.js"></script><script src="/this-is-fine/Default.38d394c2.js" nomodule="" defer></script><script type="module" src="/this-is-fine/AdminProvision.3cf9e19e.js"></script><script src="/this-is-fine/AdminProvision.d195fd59.js" nomodule="" defer></script>`,
 	Styles:  `<link rel="stylesheet" href="/this-is-fine/Default.938b4407.css"><link rel="stylesheet" href="/this-is-fine/Admin.a1e05c23.css"><link rel="stylesheet" href="/this-is-fine/User.840de3b4.css"><link rel="stylesheet" href="/this-is-fine/User.68febbf8.css"><link rel="stylesheet" href="/this-is-fine/Admin.6d2ae968.css"><link rel="stylesheet" href="/this-is-fine/AdminProvision.38d394c2.css">`,	
 }

internal/dis/component/server/assets/package.json

@@ -4,6 +4,7 @@
   "license": "AGPL-3.0-only",
   "private": true,
   "dependencies": {
+    "async-mutex": "^0.4.0",
     "dayjs": "^1.11.5",
     "highlight.js": "^11.7.0",
     "latex.css": "^1.8.0",

internal/dis/component/server/assets/src/lib/remote/index.ts

@@ -1,5 +1,6 @@
 import "./index.css"
-import connectSocket from './socket';
+import connectSocket from './socket'
+import { Mutex } from 'async-mutex'
 
 type Println = ((line: string, flush?: boolean) => void) & {
     paintedFrames: number;
@@ -122,14 +123,14 @@ export function createModal(action: string, params: string[], opts: Partial<Moda
     const button = document.createElement("button")
     button.className = "pure-button pure-button-success"
     button.append(typeof opts?.onClose === 'function' ? "Close & Finish" : "Close")
-    let success = false;
+    let result = {success: false, error: "unknown error"};
     button.addEventListener('click', function (event) {
         event.preventDefault();
 
         if (typeof opts?.onClose === 'function') {
             button.setAttribute('disabled', 'disabled')
             target.innerHTML = 'Finishing up ...'
-            opts.onClose(success)
+            opts.onClose(result.success)
             return;
         }
 
@@ -154,20 +155,38 @@ export function createModal(action: string, params: string[], opts: Partial<Moda
 
     println("Connecting ...", true)
 
+    const mutex = new Mutex();
+
     // connect to the socket and send the action
     connectSocket((socket) => {
         println("Connected", true)
         socket.send(action)
         params.forEach(p => socket.send(p))
     }, (data) => {
-        println(data);
+        mutex.runExclusive(async () => {
+            if (data instanceof Blob) {
+                result = JSON.parse(await data.text());
+                return
+            }
+
+            println(data);
+        })
     }).then(() => {
-        success = true
-        println("Connection closed.", true)
-        close();
+        mutex.runExclusive(async () => {
+            if(result.success) {
+                println("Process finished successfully. ")
+            } else {
+                println("Process failed: " + result.error)
+            }
+            println("Connection closed. ", true)
+            close();
+        })
     }).catch(() => {
-        success = false
-        println("Connection errored.", true)
-        close();
+        mutex.runExclusive(async () => {
+            println("Connection errored. ", true)
+            result = { success: false, error: "connection errored" }
+
+            close();
+        })
     });
 }

internal/dis/component/server/assets/yarn.lock

@@ -751,6 +751,13 @@ ansi-styles@^4.1.0:
   dependencies:
     color-convert "^2.0.1"
 
+async-mutex@^0.4.0:
+  version "0.4.0"
+  resolved "https://registry.yarnpkg.com/async-mutex/-/async-mutex-0.4.0.tgz#ae8048cd4d04ace94347507504b3cf15e631c25f"
+  integrity sha512-eJFZ1YhRR8UN8eBLoNzcDPcy/jqjsg6I1AP+KvWQX80BqOSW1oJPJXDylPUEeMr2ZQvHgnQ//Lp6f3RQ1zI7HA==
+  dependencies:
+    tslib "^2.4.0"
+
 base-x@^3.0.8:
   version "3.0.9"
   resolved "https://registry.yarnpkg.com/base-x/-/base-x-3.0.9.tgz#6349aaabb58526332de9f60995e548a53fe21320"