From 43200af2752a6f50a49f2685bd23644b4daaae40 Mon Sep 17 00:00:00 2001
From: Kavin <20838718+FireMasterK@users.noreply.github.com>
Date: Sat, 12 Aug 2023 13:08:09 +0100
Subject: [PATCH] Attempt to extract function from player only once.

---
 .../youtube/YoutubeThrottlingDecrypter.java    | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/YoutubeThrottlingDecrypter.java b/extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/YoutubeThrottlingDecrypter.java
index 227751e29..f6b9cca4c 100644
--- a/extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/YoutubeThrottlingDecrypter.java
+++ b/extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/YoutubeThrottlingDecrypter.java
@@ -52,9 +52,12 @@ public final class YoutubeThrottlingDecrypter {
     private static final String FUNCTION_NAMES_IN_DECRYPT_ARRAY_REGEX = "\\s*=\\s*\\[(.+?)][;,]";
 
     private static final Map<String, String> N_PARAMS_CACHE = new HashMap<>();
+    private static String playerJsCode;
     private static String decryptFunction;
     private static String decryptFunctionName;
 
+    private static final Object PLAYER_JS_CODE_LOCK = new Object();
+
     private YoutubeThrottlingDecrypter() {
         // No implementation
     }
@@ -89,12 +92,17 @@ public final class YoutubeThrottlingDecrypter {
         }
 
         try {
-            if (decryptFunction == null) {
-                final String playerJsCode
-                        = YoutubeJavaScriptExtractor.extractJavaScriptCode(videoId);
+            synchronized (PLAYER_JS_CODE_LOCK) {
+                if (playerJsCode == null) {
+                    playerJsCode = YoutubeJavaScriptExtractor.extractJavaScriptCode(videoId);
 
-                decryptFunctionName = parseDecodeFunctionName(playerJsCode);
-                decryptFunction = parseDecodeFunction(playerJsCode, decryptFunctionName);
+                    decryptFunctionName = parseDecodeFunctionName(playerJsCode);
+                    decryptFunction = parseDecodeFunction(playerJsCode, decryptFunctionName);
+                }
+            }
+
+            if (decryptFunction == null || decryptFunctionName == null) {
+                throw new ParsingException("The decryption function was not parsed correctly");
             }
 
             final String oldNParam = parseNParam(streamingUrl);