From 3a3d1d7f2bd364cdb5e81a6a1171471ca55f1fc2 Mon Sep 17 00:00:00 2001 From: XiangRongLin <41164160+XiangRongLin@users.noreply.github.com> Date: Tue, 20 Jul 2021 20:48:11 +0200 Subject: [PATCH] Make YoutubeJavaScriptExtractor and JavaScript methods static Also address review and rewrite some comments --- ...r.java => YoutubeJavaScriptExtractor.java} | 40 ++++++++++--------- .../youtube/YoutubeThrottlingDecrypter.java | 9 ++--- .../extractors/YoutubeStreamExtractor.java | 10 ++--- .../{Javascript.java => JavaScript.java} | 7 +++- ...va => YoutubeJavaScriptExtractorTest.java} | 14 +++---- 5 files changed, 41 insertions(+), 39 deletions(-) rename extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/{YoutubeJavascriptExtractor.java => YoutubeJavaScriptExtractor.java} (72%) rename extractor/src/main/java/org/schabi/newpipe/extractor/utils/{Javascript.java => JavaScript.java} (82%) rename extractor/src/test/java/org/schabi/newpipe/extractor/services/youtube/{YoutubeJavascriptExtractorTest.java => YoutubeJavaScriptExtractorTest.java} (69%) diff --git a/extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/YoutubeJavascriptExtractor.java b/extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/YoutubeJavaScriptExtractor.java similarity index 72% rename from extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/YoutubeJavascriptExtractor.java rename to extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/YoutubeJavaScriptExtractor.java index 06f2c44c2..9cfcfa3e0 100644 --- a/extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/YoutubeJavascriptExtractor.java +++ b/extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/YoutubeJavaScriptExtractor.java @@ -12,47 +12,51 @@ import org.schabi.newpipe.extractor.utils.Parser; import javax.annotation.Nonnull; /** - * Youtube restricts streaming their media in multiple ways by requiring clients to apply a cipher function + * YouTube restricts streaming their media in multiple ways by requiring clients to apply a cipher function * on parameters of requests. * The cipher function is sent alongside as a JavaScript function. *

* This class handling fetching the JavaScript file in order to allow other classes to extract the needed functions. */ -public class YoutubeJavascriptExtractor { +public class YoutubeJavaScriptExtractor { private static final String HTTPS = "https:"; - private static String cachedJavascriptCode; + private static String cachedJavaScriptCode; + + private YoutubeJavaScriptExtractor() { + } /** * Extracts the JavaScript file. The result is cached, so subsequent calls use the result of previous calls. * - * @param videoId Does not influence the result, but a valid video id can prevent tracking + * @param videoId Does not influence the result, but a valid video id may help in the chance that YouTube tracks it. * @return The whole javascript file as a string. * @throws ParsingException If the extraction failed. */ @Nonnull - public static String extractJavascriptCode(String videoId) throws ParsingException { - if (cachedJavascriptCode == null) { - final YoutubeJavascriptExtractor extractor = new YoutubeJavascriptExtractor(); - String playerJsUrl = extractor.cleanJavascriptUrl(extractor.extractJavascriptUrl(videoId)); - cachedJavascriptCode = extractor.downloadJavascriptCode(playerJsUrl); + public static String extractJavaScriptCode(String videoId) throws ParsingException { + if (cachedJavaScriptCode == null) { + final String playerJsUrl = YoutubeJavaScriptExtractor.cleanJavaScriptUrl( + YoutubeJavaScriptExtractor.extractJavaScriptUrl(videoId)); + cachedJavaScriptCode = YoutubeJavaScriptExtractor.downloadJavaScriptCode(playerJsUrl); } - return cachedJavascriptCode; + return cachedJavaScriptCode; } /** - * Same as {@link YoutubeJavascriptExtractor#extractJavascriptCode(String)} but with a constant value for videoId. + * Same as {@link YoutubeJavaScriptExtractor#extractJavaScriptCode(String)} but with a constant value for videoId. * Possible because the videoId has no influence on the result. - * - * For tracking avoidance purposes it may make sense to pass in valid video ids. + *

+ * In the off chance that YouTube tracks with which video id the request is made, it may make sense to pass in + * video ids. */ @Nonnull - public static String extractJavascriptCode() throws ParsingException { - return extractJavascriptCode("d4IGg5dqeO8"); + public static String extractJavaScriptCode() throws ParsingException { + return extractJavaScriptCode("d4IGg5dqeO8"); } - private String extractJavascriptUrl(String videoId) throws ParsingException { + private static String extractJavaScriptUrl(String videoId) throws ParsingException { try { final String embedUrl = "https://www.youtube.com/embed/" + videoId; final String embedPageContent = NewPipe.getDownloader() @@ -80,7 +84,7 @@ public class YoutubeJavascriptExtractor { throw new ParsingException("Embedded info did not provide YouTube player js url"); } - private String cleanJavascriptUrl(String playerJsUrl) { + private static String cleanJavaScriptUrl(String playerJsUrl) { if (playerJsUrl.startsWith("//")) { return HTTPS + playerJsUrl; } else if (playerJsUrl.startsWith("/")) { @@ -91,7 +95,7 @@ public class YoutubeJavascriptExtractor { } } - private String downloadJavascriptCode(String playerJsUrl) throws ParsingException { + private static String downloadJavaScriptCode(String playerJsUrl) throws ParsingException { try { return NewPipe.getDownloader().get(playerJsUrl, Localization.DEFAULT).responseBody(); } catch (Exception e) { 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 d8295113d..18cc872f3 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 @@ -1,7 +1,7 @@ package org.schabi.newpipe.extractor.services.youtube; import org.schabi.newpipe.extractor.exceptions.ParsingException; -import org.schabi.newpipe.extractor.utils.Javascript; +import org.schabi.newpipe.extractor.utils.JavaScript; import org.schabi.newpipe.extractor.utils.Parser; import java.util.regex.Pattern; @@ -35,14 +35,14 @@ public class YoutubeThrottlingDecrypter { * Otherwise use the no-arg constructor which uses a constant value. */ public YoutubeThrottlingDecrypter(String videoId) throws ParsingException { - final String playerJsCode = YoutubeJavascriptExtractor.extractJavascriptCode(videoId); + final String playerJsCode = YoutubeJavaScriptExtractor.extractJavaScriptCode(videoId); functionName = parseDecodeFunctionName(playerJsCode); function = parseDecodeFunction(playerJsCode, functionName); } public YoutubeThrottlingDecrypter() throws ParsingException { - final String playerJsCode = YoutubeJavascriptExtractor.extractJavascriptCode(); + final String playerJsCode = YoutubeJavaScriptExtractor.extractJavaScriptCode(); functionName = parseDecodeFunctionName(playerJsCode); function = parseDecodeFunction(playerJsCode, functionName); @@ -78,8 +78,7 @@ public class YoutubeThrottlingDecrypter { } private String decryptNParam(String nParam) { - Javascript javascript = new Javascript(); - return javascript.run(function, functionName, nParam); + return JavaScript.run(function, functionName, nParam); } private String replaceNParam(String url, String oldValue, String newValue) { diff --git a/extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/extractors/YoutubeStreamExtractor.java b/extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/extractors/YoutubeStreamExtractor.java index a0fa228a9..0ad22d349 100644 --- a/extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/extractors/YoutubeStreamExtractor.java +++ b/extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/extractors/YoutubeStreamExtractor.java @@ -4,10 +4,6 @@ import com.grack.nanojson.JsonArray; import com.grack.nanojson.JsonObject; import com.grack.nanojson.JsonParser; import com.grack.nanojson.JsonParserException; -import org.jsoup.Jsoup; -import org.jsoup.nodes.Document; -import org.jsoup.nodes.Element; -import org.jsoup.select.Elements; import org.mozilla.javascript.Context; import org.mozilla.javascript.Function; import org.mozilla.javascript.ScriptableObject; @@ -24,7 +20,7 @@ import org.schabi.newpipe.extractor.localization.Localization; import org.schabi.newpipe.extractor.localization.TimeAgoParser; import org.schabi.newpipe.extractor.localization.TimeAgoPatternsManager; import org.schabi.newpipe.extractor.services.youtube.ItagItem; -import org.schabi.newpipe.extractor.services.youtube.YoutubeJavascriptExtractor; +import org.schabi.newpipe.extractor.services.youtube.YoutubeJavaScriptExtractor; import org.schabi.newpipe.extractor.services.youtube.YoutubeParsingHelper; import org.schabi.newpipe.extractor.services.youtube.YoutubeThrottlingDecrypter; import org.schabi.newpipe.extractor.services.youtube.linkHandler.YoutubeChannelLinkHandlerFactory; @@ -524,7 +520,7 @@ public class YoutubeStreamExtractor extends StreamExtractor { public List getVideoStreams() throws ExtractionException { assertPageFetched(); final List videoStreams = new ArrayList<>(); - YoutubeThrottlingDecrypter throttlingDecrypter = new YoutubeThrottlingDecrypter(getId()); + final YoutubeThrottlingDecrypter throttlingDecrypter = new YoutubeThrottlingDecrypter(getId()); try { for (final Map.Entry entry : getItags(FORMATS, ItagItem.ItagType.VIDEO).entrySet()) { @@ -817,7 +813,7 @@ public class YoutubeStreamExtractor extends StreamExtractor { private String loadDeobfuscationCode() throws DeobfuscateException { try { - final String playerCode = YoutubeJavascriptExtractor.extractJavascriptCode(getId()); + final String playerCode = YoutubeJavaScriptExtractor.extractJavaScriptCode(getId()); final String deobfuscationFunctionName = getDeobfuscationFuncName(playerCode); final String functionPattern = "(" diff --git a/extractor/src/main/java/org/schabi/newpipe/extractor/utils/Javascript.java b/extractor/src/main/java/org/schabi/newpipe/extractor/utils/JavaScript.java similarity index 82% rename from extractor/src/main/java/org/schabi/newpipe/extractor/utils/Javascript.java rename to extractor/src/main/java/org/schabi/newpipe/extractor/utils/JavaScript.java index c7c81bcb5..a25b3d4ab 100644 --- a/extractor/src/main/java/org/schabi/newpipe/extractor/utils/Javascript.java +++ b/extractor/src/main/java/org/schabi/newpipe/extractor/utils/JavaScript.java @@ -4,9 +4,12 @@ import org.mozilla.javascript.Context; import org.mozilla.javascript.Function; import org.mozilla.javascript.ScriptableObject; -public class Javascript { +public class JavaScript { - public String run(String function, String functionName, String... parameters) { + private JavaScript() { + } + + public static String run(String function, String functionName, String... parameters) { try { Context context = Context.enter(); context.setOptimizationLevel(-1); diff --git a/extractor/src/test/java/org/schabi/newpipe/extractor/services/youtube/YoutubeJavascriptExtractorTest.java b/extractor/src/test/java/org/schabi/newpipe/extractor/services/youtube/YoutubeJavaScriptExtractorTest.java similarity index 69% rename from extractor/src/test/java/org/schabi/newpipe/extractor/services/youtube/YoutubeJavascriptExtractorTest.java rename to extractor/src/test/java/org/schabi/newpipe/extractor/services/youtube/YoutubeJavaScriptExtractorTest.java index c626f55da..45ebf9092 100644 --- a/extractor/src/test/java/org/schabi/newpipe/extractor/services/youtube/YoutubeJavascriptExtractorTest.java +++ b/extractor/src/test/java/org/schabi/newpipe/extractor/services/youtube/YoutubeJavaScriptExtractorTest.java @@ -12,7 +12,7 @@ import static org.hamcrest.CoreMatchers.allOf; import static org.hamcrest.CoreMatchers.containsString; import static org.hamcrest.MatcherAssert.assertThat; -public class YoutubeJavascriptExtractorTest { +public class YoutubeJavaScriptExtractorTest { @Before public void setup() throws IOException { @@ -20,20 +20,20 @@ public class YoutubeJavascriptExtractorTest { } @Test - public void testExtractJavascript__success() throws ParsingException { - String playerJsCode = YoutubeJavascriptExtractor.extractJavascriptCode("d4IGg5dqeO8"); + public void testExtractJavaScript__success() throws ParsingException { + String playerJsCode = YoutubeJavaScriptExtractor.extractJavaScriptCode("d4IGg5dqeO8"); assertPlayerJsCode(playerJsCode); - playerJsCode = YoutubeJavascriptExtractor.extractJavascriptCode(); + playerJsCode = YoutubeJavaScriptExtractor.extractJavaScriptCode(); assertPlayerJsCode(playerJsCode); } @Test - public void testExtractJavascript__invalidVideoId__success() throws ParsingException { - String playerJsCode = YoutubeJavascriptExtractor.extractJavascriptCode("not_a_video_id"); + public void testExtractJavaScript__invalidVideoId__success() throws ParsingException { + String playerJsCode = YoutubeJavaScriptExtractor.extractJavaScriptCode("not_a_video_id"); assertPlayerJsCode(playerJsCode); - playerJsCode = YoutubeJavascriptExtractor.extractJavascriptCode("11-chars123"); + playerJsCode = YoutubeJavaScriptExtractor.extractJavaScriptCode("11-chars123"); assertPlayerJsCode(playerJsCode); }