move sparkplug decoding to backend

backend/src/Model/Base64Message.ts

@@ -1,15 +1,18 @@
-const { Base64 } = require('js-base64')
+
+import { Base64 } from 'js-base64'
+import { Decoder } from './Decoder'
 
 export class Base64Message {
   private base64Message: string
   private unicodeValue: string
-
+  public decoder: Decoder
   public length: number
 
   private constructor(base64Str: string) {
     this.base64Message = base64Str
     this.unicodeValue = Base64.decode(base64Str)
     this.length = base64Str.length
+    this.decoder = Decoder.NONE
   }
 
   public static toUnicodeString(message: Base64Message) {
@@ -27,15 +30,4 @@ export class Base64Message {
   public static toDataUri(message: Base64Message, mimeType: string) {
     return `data:${mimeType};base64,${message.base64Message}`
   }
-
-  public static toUint8Array(message: Base64Message) {
-    const binaryString = window.atob(message.base64Message)
-    const len = binaryString.length
-    const bytes = new Uint8Array(len)
-    for (const i of Array.from(Array(len).keys())) {
-      bytes[i] = binaryString.charCodeAt(i)
-    }
-
-    return bytes
-  }
 }

backend/src/Model/Decoder.ts

@@ -0,0 +1,4 @@
+export enum Decoder {
+    NONE,
+    SPARKPLUG
+}

backend/src/Model/sparkplugb.ts

@@ -1,10 +1,24 @@
-const protobuf = require('protobufjs')
-const sparkplugBProto = require('../../../res/sparkplug_b.proto')
+import { readFileSync } from 'fs'
+import * as protobuf from 'protobufjs'
+import { Base64Message } from './Base64Message';
+import { Decoder } from './Decoder';
 
-export let Payload = undefined
+const buffer = readFileSync(require.resolve('../../../../res/sparkplug_b.proto'));
+const root = protobuf.parse(buffer.toString()).root
+export let SparkplugPayload = root.lookupType('com.cirruslink.sparkplug.protobuf.Payload')
 
-export function loadSparkplugBPayload() {
-  protobuf.load(sparkplugBProto).then((root: any) => {
-    Payload = root.lookupType('com.cirruslink.sparkplug.protobuf.Payload')
-  })
+export const SparkplugDecoder = {
+  decode(input: Buffer): Base64Message | undefined {
+    try {
+      let message = Base64Message.fromString(
+        JSON.stringify(
+          SparkplugPayload.toObject(SparkplugPayload.decode(new Uint8Array(input)))
+        )
+      )
+      message.decoder = Decoder.SPARKPLUG
+      return message
+    } catch {
+      // ignore
+    }
+  }
 }

backend/src/Model/spec/makeTreeNode.ts

@@ -2,11 +2,42 @@ import { TreeNodeFactory } from '../'
 import { Base64Message } from '../Base64Message'
 import { TreeNode } from '../TreeNode'
 import { MqttMessage } from '../../../../events'
+import { SparkplugPayload } from '../sparkplugb'
+
+interface Decoder {
+  decode(input: string): string | null
+}
+
+const SparkplugDecoder = {
+  decoderTime: 0,
+  encoder: new TextEncoder(),
+  decode(input: string): string | null {
+    if (!SparkplugPayload) {
+      return null
+    }
+
+    const start = performance.now()
+
+    let result
+    try {
+      result = JSON.stringify(SparkplugPayload.toObject(SparkplugPayload.decode(this.encoder.encode(input))))
+    } catch { }
+
+    this.decoderTime += performance.now() - start;
+    return result ?? null
+  }
+}
+
+let i = 1
+setInterval(() => {
+  console.log(`decoder time after ${i++ * 10} seconds: ${SparkplugDecoder.decoderTime}ms`)
+}, 10000)
 
 export function makeTreeNode(topic: string, message?: string): TreeNode<any> {
+  let sparkplugMessage = message && SparkplugDecoder.decode(message)
   const mqttMessage: MqttMessage = {
     topic,
-    payload: message ? Base64Message.fromString(message) : null,
+    payload: message ? Base64Message.fromString(sparkplugMessage ?? message) : null,
     qos: 0,
     retain: false,
     messageId: undefined,

backend/src/index.ts

@@ -10,6 +10,7 @@ import {
   makePublishEvent,
   removeConnection,
 } from '../../events'
+import { SparkplugDecoder } from './Model/sparkplugb'
 
 export class ConnectionManager {
   private connections: { [s: string]: DataSource<any> } = {}
@@ -48,7 +49,7 @@ export class ConnectionManager {
 
       backendEvents.emit(messageEvent, {
         topic,
-        payload: Base64Message.fromBuffer(buffer),
+        payload: SparkplugDecoder.decode(buffer) ?? Base64Message.fromBuffer(buffer),
         qos: packet.qos,
         retain: packet.retain,
         messageId: packet.messageId,