[YouTube] Add an interface and a class to fetch and provide poTokens

extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/PoTokenProvider.java

@@ -0,0 +1,120 @@
+package org.schabi.newpipe.extractor.services.youtube;
+
+import javax.annotation.Nullable;
+
+/**
+ * Interface to provide {@code poToken}s to YouTube player requests.
+ *
+ * <p>
+ * On some major clients, YouTube requires that the integrity of the device passes some checks to
+ * allow playback.
+ * </p>
+ *
+ * <p>
+ * These checks involve running codes to verify the integrity and using their result to generate
+ * one or multiple {@code poToken}(s) (which stands for proof of origin token(s)).
+ * </p>
+ *
+ * <p>
+ * These tokens may have a role in triggering the sign in requirement.
+ * </p>
+ *
+ * <p>
+ * If an implementation does not want to return a {@code poToken} for a specific client, it <b>must
+ * return {@code null}</b>.
+ * </p>
+ *
+ * <p>
+ * <b>Implementations of this interface are expected to be thread-safe, as they may be accessed by
+ * multiple threads.</b>
+ * </p>
+ */
+public interface PoTokenProvider {
+
+    /**
+     * Get a {@link PoTokenResult} specific to the desktop website, a.k.a. the WEB InnerTube client.
+     *
+     * <p>
+     * To be generated and valid, {@code poToken}s from this client must be generated using Google's
+     * BotGuard machine, which requires a JavaScript engine with a good DOM implementation. They
+     * must be added to adaptive/DASH streaming URLs with the {@code pot} parameter.
+     * </p>
+     *
+     * <p>
+     * Note that YouTube desktop website generates two {@code poToken}s:
+     * - one for the player requests {@code poToken}s, using the videoId as the minter value;
+     * - one for the streaming URLs, using a visitor data for logged-out users as the minter value.
+     * </p>
+     *
+     * @return a {@link PoTokenResult} specific to the WEB InnerTube client
+     */
+    @Nullable
+    PoTokenResult getWebClientPoToken(String videoId);
+
+    /**
+     * Get a {@link PoTokenResult} specific to the web embeds, a.k.a. the WEB_EMBEDDED_PLAYER
+     * InnerTube client.
+     *
+     * <p>
+     * To be generated and valid, {@code poToken}s from this client must be generated using Google's
+     * BotGuard machine, which requires a JavaScript engine with a good DOM implementation. They
+     * should be added to adaptive/DASH streaming URLs with the {@code pot} parameter.
+     * </p>
+     *
+     * <p>
+     * As of writing, like the YouTube desktop website previously did, it generates only one
+     * {@code poToken}, sent in player requests and streaming URLs, using a visitor data for
+     * logged-out users. {@code poToken}s do not seem to be mandatory for now on this client.
+     * </p>
+     *
+     * @return a {@link PoTokenResult} specific to the WEB_EMBEDDED_PLAYER InnerTube client
+     */
+    @Nullable
+    PoTokenResult getWebEmbedClientPoToken(String videoId);
+
+    /**
+     * Get a {@link PoTokenResult} specific to the Android app, a.k.a. the ANDROID InnerTube client.
+     *
+     * <p>
+     * Implementation details are not known, the app uses DroidGuard, a downloaded native virtual
+     * machine ran by Google Play Services for which its code is updated pretty frequently.
+     * </p>
+     *
+     * <p>
+     * As of writing, DroidGuard seem to check for the Android app signature and package ID, as
+     * non-rooted YouTube patched with reVanced doesn't work without spoofing another InnerTube
+     * client while the rooted version works without any client spoofing.
+     * </p>
+     *
+     * <p>
+     * There should be only one {@code poToken} needed for the player requests, it shouldn't be
+     * required for regular adaptive URLs (i.e. not server adaptive bitrate (SABR) URLs). HLS
+     * formats returned (only for premieres and running and post-live livestreams) in the client's
+     * HLS manifest URL should work without {@code poToken}s.
+     * </p>
+     *
+     * @return a {@link PoTokenResult} specific to the ANDROID InnerTube client
+     */
+    @Nullable
+    PoTokenResult getAndroidClientPoToken(String videoId);
+
+    /**
+     * Get a {@link PoTokenResult} specific to the iOS app, a.k.a. the IOS InnerTube client.
+     *
+     * <p>
+     * Implementation details are not known, the app seem to use something called iosGuard which
+     * should be similar to Android's DroidGuard. It may rely on Apple's attestation APIs.
+     * </p>
+     *
+     * <p>
+     * As of writing, there should be only one {@code poToken} needed for the player requests, it
+     * shouldn't be required for regular adaptive URLs (i.e. not server adaptive bitrate (SABR)
+     * URLs). HLS formats returned in the client's HLS manifest URL should also work without a
+     * {@code poToken}.
+     * </p>
+     *
+     * @return a {@link PoTokenResult} specific to the IOS InnerTube client
+     */
+    @Nullable
+    PoTokenResult getIosClientPoToken(String videoId);
+}

extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/PoTokenResult.java

@@ -0,0 +1,52 @@
+package org.schabi.newpipe.extractor.services.youtube;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import java.util.Objects;
+
+/**
+ * The result of a supported/successful {@code poToken} extraction request by a
+ * {@link PoTokenProvider}.
+ */
+public final class PoTokenResult {
+
+    /**
+     * The visitor data associated with a {@code poToken}.
+     */
+    @Nonnull
+    public final String visitorData;
+
+    /**
+     * The {@code poToken} of a player request, a Protobuf object encoded as a base 64 string.
+     */
+    @Nonnull
+    public final String playerRequestPoToken;
+
+    /**
+     * The {@code poToken} to be appended to streaming URLs, a Protobuf object encoded as a base
+     * 64 string.
+     *
+     * <p>
+     * It may be required on some clients such as HTML5 ones and may also differ from the player
+     * request {@code poToken}.
+     * </p>
+     */
+    @Nullable
+    public final String streamingDataPoToken;
+
+    /**
+     * Construct a {@link PoTokenResult} instance.
+     *
+     * @param visitorData          see {@link #visitorData}
+     * @param playerRequestPoToken see {@link #playerRequestPoToken}
+     * @param streamingDataPoToken see {@link #streamingDataPoToken}
+     * @throws NullPointerException if a non-null parameter is null
+     */
+    public PoTokenResult(@Nonnull final String visitorData,
+                         @Nonnull final String playerRequestPoToken,
+                         @Nullable final String streamingDataPoToken) {
+        this.visitorData = Objects.requireNonNull(visitorData);
+        this.playerRequestPoToken = Objects.requireNonNull(playerRequestPoToken);
+        this.streamingDataPoToken = streamingDataPoToken;
+    }
+}