Initial commit.

meson.build

@@ -0,0 +1,13 @@
+project('vala app', 'vala', 'c')
+
+dependencies = [
+    dependency('glib-2.0'),
+    dependency('json-glib-1.0'),
+    dependency('gobject-2.0'),
+    dependency('libsoup-2.4'),
+]
+
+
+sources = files('src/main.vala')
+
+executable('youtube-extractor', sources, dependencies: dependencies)

src/main.vala

@@ -0,0 +1,86 @@
+void main () {
+    var session = new Soup.Session ();
+    initialize_user_agent (session);
+
+    var message =
+      new Soup.Message ("GET", "https://www.youtube.com/watch?v=g2cF4-tHvqI");
+    session.send_message (message);
+
+    var youtube_response = (string) message.response_body.data;
+
+    var regex = /ytInitialPlayerResponse\s*=\s*({.+?})\s*;/;
+
+    MatchInfo info;
+    regex.match (youtube_response, 0, out info);
+    var json_parser = new Json.Parser ();
+    json_parser.load_from_data ( info.fetch (1), -1 );
+    var yt_initial_player_response = json_parser.get_root ().get_object ();
+    var streaming_data = yt_initial_player_response.get_object_member("streamingData");
+    var adaptive_formats = streaming_data.get_array_member("formats");
+    adaptive_formats.foreach_element((format) => {
+        print ("%lld\n", format.get_object_element (0).get_int_member ("itag"));
+    });
+//    print ("%s\n", info.fetch (1));
+}
+
+void initialize_user_agent (Soup.Session session) {
+    var cookie_jar = new Soup.CookieJar ();
+    session.add_feature (cookie_jar);
+
+    do_main_page_youtube_request (session);
+
+    if (!has_consent (cookie_jar)) {
+    print ("No consent found\n");
+    consent (cookie_jar);
+  }
+}
+
+void consent (Soup.CookieJar cookie_jar) {
+    var youtube_uri = new Soup.URI ("https://youtube.com");
+    var cookies = cookie_jar.get_cookie_list (youtube_uri, false);
+
+    unowned var cookie = cookies.search<string> ("CONSENT", (cookie, name) => {
+        return cookie.name == name ? 0 : 1;
+    });
+
+    if (cookie == null || is_consent_yes (cookie.data))
+    return;
+
+    var consent_id = extract_consent_id (cookie.data);
+    var new_cookie_value = "YES+cb.20210328-17-p0.en+FX+" + consent_id;
+
+    cookie_jar.delete_cookie (cookie.data);
+    cookie_jar.add_cookie (
+      new Soup.Cookie ("CONSENT", new_cookie_value, ".youtube.com", "/", -1));
+}
+
+string extract_consent_id (Soup.Cookie cookie) {
+    var regex = /^PENDING\+(\d+)/;
+
+    MatchInfo info;
+    regex.match (cookie.@value, 0, out info);
+
+    return info.fetch (1);
+}
+
+bool is_consent_yes (Soup.Cookie cookie) {
+    var regex = /YES/;
+    return regex.match (cookie.@value);
+}
+
+bool has_consent (Soup.CookieJar cookie_jar) {
+    var youtube_uri = new Soup.URI ("https://youtube.com");
+    var cookies = cookie_jar.get_cookie_list (youtube_uri, false);
+
+    foreach (var cookie in cookies) {
+    if (cookie.name == "__Secure-3PSID")
+      return true;
+  }
+
+    return false;
+}
+
+void do_main_page_youtube_request (Soup.Session session) {
+    var message = new Soup.Message ("GET", "https://www.youtube.com");
+    session.send_message (message);
+}