change(player): detect gzip file after decoding

frontend/app/player/web/network/crypto.ts

@@ -21,18 +21,21 @@ export function decryptSessionBytes(cypher: Uint8Array, keyString: string): Prom
 		.then(key => crypto.subtle.decrypt({ name: "AES-CBC", iv: iv}, key, cypher))
 		.then((bArray: ArrayBuffer) => new Uint8Array(bArray))
 		.then(async (u8Array: Uint8Array) => {
-			const now = performance.now()
-			const data = gunzipSync(u8Array)
-			console.debug(
-				"Decompression time",
-				performance.now() - now,
-				'size',
-				Math.floor(u8Array.byteLength/1024),
-				'->',
-				Math.floor(data.byteLength/1024),
-				'kb'
-			)
-			return data
+			const isGzip = u8Array[0] === 0x1F && u8Array[1] === 0x8B && u8Array[2] === 0x08;
+			if (isGzip) {
+				const now = performance.now()
+				const data = gunzipSync(u8Array)
+				console.debug(
+					"Decompression time",
+					performance.now() - now,
+					'size',
+					Math.floor(u8Array.byteLength/1024),
+					'->',
+					Math.floor(data.byteLength/1024),
+					'kb'
+				)
+				return data
+			} else return u8Array
 		})
 	//?? TS doesn not catch the `decrypt`` returning type
 }

tracker/tracker/src/main/app/index.ts

@@ -180,7 +180,7 @@ export default class App {
         } else if (data.type === 'compress') {
           const batch = data.batch
           const batchSize = batch.byteLength
-          if (batchSize > this.compressionThreshold) {
+          if (batchSize > 10) {
             gzip(data.batch, { mtime: 0 }, (err, result) => {
               if (err) console.error(err)
               // @ts-ignore

tracker/tracker/src/webworker/index.ts

@@ -102,7 +102,7 @@ self.onmessage = ({ data }: any): any => {
 
   if (data.type === 'compressed') {
     if (!sender) {
-      console.debug('WebWorker: sender not initialised. Received auth.')
+      console.debug('WebWorker: sender not initialised. Compressed batch.')
       initiateRestart()
       return
     }
@@ -110,7 +110,7 @@ self.onmessage = ({ data }: any): any => {
   }
   if (data.type === 'uncompressed') {
     if (!sender) {
-      console.debug('WebWorker: sender not initialised. Received auth.')
+      console.debug('WebWorker: sender not initialised. Uncompressed batch.')
       initiateRestart()
       return
     }
@@ -139,7 +139,6 @@ self.onmessage = ({ data }: any): any => {
       data.pageNo,
       data.timestamp,
       data.url,
-      // onBatch
       (batch) => sender && sender.push(batch),
     )
     if (sendIntervalID === null) {