feat: fetch NSFW tweets via authenticated twitter API fallback

crates/x-media/Cargo.toml

@@ -13,6 +13,7 @@ url = "2.5.2"
 bytes = "1"
 zip = "2"
 tempfile = "3"
+rand = "0.8"
 log = "0.4"
 tokio = { version = "1.40", features = ["time"] }
 

crates/x-media/src/site/mod.rs

@@ -89,6 +89,9 @@ pub enum FetchError {
     Pixiv(PixivError),
     NotFound,
     Blocked,
+    /// The post exists but its content is withheld (twitter NSFW /
+    /// age-restricted tweets come back as an empty `{}` from syndication).
+    Sensitive,
 }
 
 impl fmt::Display for FetchError {
@@ -99,6 +102,7 @@ impl fmt::Display for FetchError {
             FetchError::Pixiv(e) => write!(f, "pixiv error: {e}"),
             FetchError::NotFound => write!(f, "not found"),
             FetchError::Blocked => write!(f, "blocked"),
+            FetchError::Sensitive => write!(f, "content withheld (sensitive)"),
         }
     }
 }
@@ -109,7 +113,7 @@ impl std::error::Error for FetchError {
             FetchError::Http(e) => Some(e),
             FetchError::Json(e) => Some(e),
             FetchError::Pixiv(e) => Some(e),
-            FetchError::NotFound | FetchError::Blocked => None,
+            FetchError::NotFound | FetchError::Blocked | FetchError::Sensitive => None,
         }
     }
 }

crates/x-media/src/site/twitter/auth.rs

@@ -0,0 +1,368 @@
+//! Authenticated fallback for tweets the public syndication endpoint refuses
+//! to serve (NSFW / age-restricted tweets come back as an empty `{}`).
+//!
+//! Mirrors nazurin's web API client ([`web.py`]) and is used *only* when
+//! syndication reports [`FetchError::Sensitive`]: the private GraphQL
+//! `TweetDetail` endpoint, authenticated with a browser session cookie from
+//! `TWITTER_AUTH_TOKEN` (the `auth_token` cookie value of a logged-in x.com
+//! session). A fresh random `ct0` is generated per call; X checks that the
+//! `x-csrf-token` header matches the cookie, not that it issued the value.
+//!
+//! [`web.py`]: https://github.com/y-young/nazurin/blob/master/nazurin/sites/twitter/api/web.py
+//!
+//! # Caveats
+//! - X rotates the GraphQL query id when it rolls the web app; if requests
+//!   start failing, update [`TWEET_DETAIL_QUERY_ID`].
+//! - X may require an `x-client-transaction-id` (derived from the home page
+//!   `<meta name="twitter-site-verification">` key + the ondemand JS bundle);
+//!   if requests 403, add that step (see nazurin's `_generate_transaction_id`).
+
+use std::sync::LazyLock;
+
+use serde_json::{json, Value};
+
+use crate::site::FetchError;
+
+use super::interface::Tweet;
+
+/// `auth_token` cookie of a logged-in x.com session; enables the fallback.
+static AUTH_TOKEN: LazyLock<Option<String>> = LazyLock::new(|| {
+    std::env::var("TWITTER_AUTH_TOKEN")
+        .ok()
+        .filter(|s| !s.is_empty())
+});
+
+/// Public "logged in" client token used by the x.com web app.
+const LOGGED_IN_BEARER: &str =
+    "Bearer AAAAAAAAAAAAAAAAAAAAANRILgAAAAAAnNwIzUejRCOuH5E6I8xnZz4puTs%3D1Zv7ttfk8LF81IUq16cHjhLTvJu4FA33AGWWjCpTnA";
+
+/// `TweetDetail` query id (from nazurin; rotates when X rolls the app).
+const TWEET_DETAIL_QUERY_ID: &str = "_8aYOgEDz35BrBcBal1-_w";
+
+fn variables(id: &str) -> Value {
+    json!({
+        "focalTweetId": id,
+        "with_rux_injections": false,
+        "includePromotedContent": false,
+        "withCommunity": true,
+        "withQuickPromoteEligibilityTweetFields": false,
+        "withBirdwatchNotes": false,
+        "withVoice": true,
+    })
+}
+
+fn features() -> Value {
+    json!({
+        "rweb_video_screen_enabled": false,
+        "profile_label_improvements_pcf_label_in_post_enabled": true,
+        "rweb_tipjar_consumption_enabled": true,
+        "verified_phone_label_enabled": false,
+        "creator_subscriptions_tweet_preview_api_enabled": true,
+        "responsive_web_graphql_timeline_navigation_enabled": true,
+        "responsive_web_graphql_skip_user_profile_image_extensions_enabled": false,
+        "premium_content_api_read_enabled": false,
+        "communities_web_enable_tweet_community_results_fetch": true,
+        "c9s_tweet_anatomy_moderator_badge_enabled": true,
+        "responsive_web_grok_analyze_button_fetch_trends_enabled": false,
+        "responsive_web_grok_analyze_post_followups_enabled": true,
+        "responsive_web_jetfuel_frame": false,
+        "responsive_web_grok_share_attachment_enabled": true,
+        "articles_preview_enabled": true,
+        "responsive_web_edit_tweet_api_enabled": true,
+        "graphql_is_translatable_rweb_tweet_is_translatable_enabled": true,
+        "view_counts_everywhere_api_enabled": true,
+        "longform_notetweets_consumption_enabled": true,
+        "responsive_web_twitter_article_tweet_consumption_enabled": true,
+        "tweet_awards_web_tipping_enabled": false,
+        "responsive_web_grok_show_grok_translated_post": false,
+        "responsive_web_grok_analysis_button_from_backend": true,
+        "creator_subscriptions_quote_tweet_preview_enabled": false,
+        "freedom_of_speech_not_reach_fetch_enabled": true,
+        "standardized_nudges_misinfo": true,
+        "tweet_with_visibility_results_prefer_gql_limited_actions_policy_enabled": true,
+        "longform_notetweets_rich_text_read_enabled": true,
+        "longform_notetweets_inline_media_enabled": true,
+        "responsive_web_grok_image_annotation_enabled": true,
+        "responsive_web_enhance_cards_enabled": false,
+    })
+}
+
+/// Whether the authenticated fallback is available.
+pub fn enabled() -> bool {
+    AUTH_TOKEN.is_some()
+}
+
+/// Fetches a tweet as the logged-in user via the private GraphQL API.
+/// Returns the syndication-shaped [`Tweet`] (media included for NSFW posts).
+pub async fn fetch(id: &str) -> Result<Tweet, FetchError> {
+    let token = AUTH_TOKEN
+        .as_deref()
+        .ok_or(FetchError::Sensitive)?;
+    // 16 random bytes as 32 hex chars: X rejects ct0 values of any other
+    // length with 403 code 353 ("matching csrf cookie and header").
+    let ct0: String = (0..16)
+        .map(|_| format!("{:02x}", rand::random::<u8>()))
+        .collect();
+
+    let response = crate::site::CLIENT
+        .get(format!(
+            "https://x.com/i/api/graphql/{TWEET_DETAIL_QUERY_ID}/TweetDetail"
+        ))
+        .query(&[
+            ("variables", variables(id).to_string()),
+            ("features", features().to_string()),
+        ])
+        .header("authorization", LOGGED_IN_BEARER)
+        .header("x-csrf-token", &ct0)
+        .header("x-twitter-auth-type", "OAuth2Session")
+        .header("cookie", format!("auth_token={token}; ct0={ct0}"))
+        .header("x-twitter-client-language", "en")
+        .header("x-twitter-active-user", "yes")
+        .header("referer", "https://x.com/")
+        .send()
+        .await?;
+    if !response.status().is_success() {
+        log::warn!("twitter auth fetch {id}: HTTP {}", response.status());
+        return Err(FetchError::NotFound);
+    }
+    let text = response.text().await?;
+    let json: Value = serde_json::from_str(&text)?;
+    let result = parse_tweet_result(&json, id)?;
+    let syndication_shape = to_syndication_shape(&result)
+        .ok_or_else(|| FetchError::Json(serde_json::Error::io(std::io::Error::new(
+            std::io::ErrorKind::InvalidData,
+            "missing tweet fields in GraphQL response",
+        ))))?;
+    Tweet::from_syndication_json(&syndication_shape.to_string()).map_err(FetchError::Json)
+}
+
+/// Locates the tweet for `id` in a `TweetDetail` response and unwraps
+/// visibility wrappers / retweets, mirroring nazurin's `_process_response`.
+fn parse_tweet_result(json: &Value, id: &str) -> Result<Value, FetchError> {
+    if let Some(errors) = json.get("errors").and_then(|e| e.as_array()) {
+        let messages: Vec<&str> = errors
+            .iter()
+            .filter_map(|e| e.get("message").and_then(|m| m.as_str()))
+            .collect();
+        log::warn!("twitter auth fetch {id} failed: {}", messages.join("; "));
+        return Err(FetchError::NotFound);
+    }
+
+    let instructions = json
+        .pointer("/data/threaded_conversation_with_injections_v2/instructions")
+        .and_then(|v| v.as_array())
+        .ok_or(FetchError::NotFound)?;
+    for instruction in instructions {
+        if instruction.get("type").and_then(|t| t.as_str()) != Some("TimelineAddEntries") {
+            continue;
+        }
+        let entries = instruction
+            .get("entries")
+            .and_then(|e| e.as_array())
+            .ok_or(FetchError::NotFound)?;
+        let wanted = format!("tweet-{id}");
+        for entry in entries {
+            if entry.get("entryId").and_then(|i| i.as_str()) == Some(wanted.as_str()) {
+                let result = entry
+                    .pointer("/content/itemContent/tweet_results/result")
+                    .ok_or(FetchError::NotFound)?;
+                return normalize_tweet_result(result);
+            }
+        }
+    }
+    Err(FetchError::NotFound)
+}
+
+/// Unwraps TweetTombstone/TweetUnavailable errors, the
+/// TweetWithVisibilityResults wrapper and retweets, returning the
+/// `{core, legacy, ...}` tweet object.
+fn normalize_tweet_result(result: &Value) -> Result<Value, FetchError> {
+    match result.get("__typename").and_then(|t| t.as_str()) {
+        Some("TweetTombstone") => {
+            let text = result
+                .pointer("/tombstone/text/text")
+                .and_then(|t| t.as_str())
+                .unwrap_or("tweet is unavailable");
+            log::warn!("twitter auth fetch: tombstone: {text}");
+            return Err(FetchError::NotFound);
+        }
+        Some("TweetUnavailable") => {
+            let reason = result
+                .get("reason")
+                .and_then(|r| r.as_str())
+                .unwrap_or("unknown");
+            log::warn!("twitter auth fetch: tweet unavailable: {reason}");
+            return Err(FetchError::NotFound);
+        }
+        _ => {}
+    }
+
+    // TweetWithVisibilityResults (e.g. limited replies) nests the real tweet.
+    let tweet = result.get("tweet").unwrap_or(result);
+    // A retweet's media lives on the original tweet.
+    if let Some(original) = tweet.pointer("/legacy/retweeted_status_result/result") {
+        return Ok(original.clone());
+    }
+    Ok(tweet.clone())
+}
+
+/// Maps a GraphQL `{core, legacy, ...}` tweet onto the syndication JSON
+/// shape [`Tweet::from_syndication_json`] parses, so the existing text /
+/// media handling (t.co expansion, `name=orig`, mp4 variant) is reused.
+fn to_syndication_shape(tweet: &Value) -> Option<Value> {
+    let legacy = tweet.get("legacy")?;
+    let user = tweet.pointer("/core/user_results/result/legacy")?;
+    Some(json!({
+        "id_str": legacy.get("id_str"),
+        "text": legacy.get("full_text"),
+        "user": {
+            "name": user.get("name"),
+            "screen_name": user.get("screen_name"),
+        },
+        "possibly_sensitive": legacy.get("possibly_sensitive"),
+        "display_text_range": legacy.get("display_text_range"),
+        "entities": legacy.get("entities"),
+        "mediaDetails": legacy.pointer("/extended_entities/media"),
+    }))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn tweet_result() -> Value {
+        json!({
+            "__typename": "Tweet",
+            "core": {
+                "user_results": {
+                    "result": {
+                        "legacy": { "name": "Display Name", "screen_name": "nsfw_author" }
+                    }
+                }
+            },
+            "legacy": {
+                "id_str": "2083868672721039569",
+                "full_text": "nsfw content https://t.co/abc123",
+                "display_text_range": [0, 12],
+                "possibly_sensitive": true,
+                "entities": {
+                    "urls": [
+                        { "url": "https://t.co/abc123", "expanded_url": "https://example.com/x" }
+                    ]
+                },
+                "extended_entities": {
+                    "media": [
+                        {
+                            "type": "photo",
+                            "media_url_https": "https://pbs.twimg.com/media/nsfw.jpg",
+                            "original_info": { "width": 1200, "height": 800 }
+                        },
+                        {
+                            "type": "video",
+                            "media_url_https": "https://pbs.twimg.com/thumb.jpg",
+                            "video_info": {
+                                "variants": [
+                                    { "content_type": "application/x-mpegURL", "url": "https://x.com/pl.m3u8" },
+                                    { "content_type": "video/mp4", "url": "https://video.twimg.com/nsfw.mp4" }
+                                ]
+                            }
+                        }
+                    ]
+                }
+            }
+        })
+    }
+
+    fn conversation(tweet: Value) -> Value {
+        json!({
+            "data": {
+                "threaded_conversation_with_injections_v2": {
+                    "instructions": [
+                        { "type": "TimelineAddEntries", "entries": [
+                            { "entryId": "tweet-2083868672721039569",
+                              "content": { "itemContent": { "tweet_results": { "result": tweet } } } }
+                        ]}
+                    ]
+                }
+            }
+        })
+    }
+
+    #[test]
+    fn parses_graphql_tweet_into_fetched() {
+        let json = conversation(tweet_result());
+        let result = parse_tweet_result(&json, "2083868672721039569").unwrap();
+        let shape = to_syndication_shape(&result).unwrap();
+        let tweet = Tweet::from_syndication_json(&shape.to_string()).unwrap();
+        let fetched: crate::site::Fetched = tweet.into();
+
+        assert!(fetched.sensitive);
+        assert_eq!(fetched.media.len(), 2);
+        match &fetched.media[0] {
+            crate::media::Media::Illustration { url, .. } => {
+                assert_eq!(url, "https://pbs.twimg.com/media/nsfw.jpg?name=orig");
+            }
+            other => panic!("expected illustration, got {other:?}"),
+        }
+        match &fetched.media[1] {
+            crate::media::Media::Video { url, .. } => {
+                assert_eq!(url, "https://video.twimg.com/nsfw.mp4");
+            }
+            other => panic!("expected video, got {other:?}"),
+        }
+        assert_eq!(fetched.source_url, "https://x.com/nsfw_author/status/2083868672721039569");
+        // display_text_range cuts the trailing t.co link.
+        assert_eq!(fetched.title, "nsfw content");
+    }
+
+    #[test]
+    fn unwraps_retweet_to_original() {
+        let original = tweet_result();
+        let mut rt = tweet_result();
+        rt["legacy"]["retweeted_status_result"] = json!({ "result": original });
+        let json = conversation(rt);
+        let result = parse_tweet_result(&json, "2083868672721039569").unwrap();
+        assert!(result.pointer("/legacy/retweeted_status_result").is_none());
+        assert_eq!(result.pointer("/legacy/id_str").unwrap(), "2083868672721039569");
+    }
+
+    #[test]
+    fn error_response_maps_to_not_found() {
+        let json = json!({ "errors": [{ "message": "NsfwLoggedOut" }] });
+        assert!(matches!(
+            parse_tweet_result(&json, "1"),
+            Err(FetchError::NotFound)
+        ));
+    }
+
+    #[test]
+    fn missing_entry_maps_to_not_found() {
+        let json = conversation(json!({ "__typename": "Tweet" }));
+        assert!(matches!(
+            parse_tweet_result(&json, "999"),
+            Err(FetchError::NotFound)
+        ));
+    }
+
+    #[test]
+    fn tombstone_maps_to_not_found() {
+        let tombstone = json!({
+            "__typename": "TweetTombstone",
+            "tombstone": { "text": { "text": "Age-restricted adult content" } }
+        });
+        let json = conversation(tombstone);
+        assert!(matches!(
+            parse_tweet_result(&json, "2083868672721039569"),
+            Err(FetchError::NotFound)
+        ));
+    }
+
+    #[test]
+    fn visibility_wrapper_unwraps() {
+        let inner = tweet_result();
+        let wrapped = json!({ "__typename": "TweetWithVisibilityResults", "tweet": inner });
+        let json = conversation(wrapped);
+        let result = parse_tweet_result(&json, "2083868672721039569").unwrap();
+        assert_eq!(result.get("__typename").unwrap(), "Tweet");
+    }
+}

crates/x-media/src/site/twitter/interface.rs

@@ -19,7 +19,44 @@ pub async fn fetch_from_url(url: &str) -> Result<Fetched, FetchError> {
         .and_then(|caps| caps.get(1))
         .map(|m| m.as_str())
         .ok_or(FetchError::NotFound)?;
-    Ok(fetch(id).await?.into())
+    match fetch(id).await {
+        Ok(tweet) => Ok(tweet.into()),
+        // Syndication withholds NSFW/age-restricted tweets (empty `{}`).
+        // Retry as the logged-in user when TWITTER_AUTH_TOKEN is set;
+        // otherwise degrade to an empty result (the bot replies
+        // "No media found").
+        Err(FetchError::Sensitive) => {
+            if super::auth::enabled() {
+                match super::auth::fetch(id).await {
+                    Ok(tweet) => Ok(tweet.into()),
+                    Err(e) => {
+                        log::warn!("twitter auth fallback failed for {id}: {e}");
+                        Ok(empty_fetched(url))
+                    }
+                }
+            } else {
+                log::info!(
+                    "tweet {id} is sensitive; set TWITTER_AUTH_TOKEN to fetch NSFW media"
+                );
+                Ok(empty_fetched(url))
+            }
+        }
+        Err(e) => Err(e),
+    }
+}
+
+/// A Fetched with no media for withheld tweets: the bot replies
+/// "No media found" and moves on instead of erroring.
+fn empty_fetched(url: &str) -> Fetched {
+    Fetched {
+        source_url: url.to_string(),
+        caption: url.to_string(),
+        title: String::new(),
+        media: vec![],
+        sensitive: true,
+        render_data: None,
+        _keep_alive: None,
+    }
 }
 
 /// Fetches a tweet from the syndication endpoint. Deleted/blocked tweets
@@ -44,6 +81,15 @@ pub async fn fetch(id: &str) -> Result<Tweet, FetchError> {
     {
         return Err(FetchError::NotFound);
     }
+    // NSFW / age-restricted tweets exist but are served as an empty `{}` —
+    // they surface as FetchError::Sensitive so the caller can retry as a
+    // logged-in user.
+    if serde_json::from_str::<serde_json::Value>(&text)
+        .map(|v| v.get("id_str").is_none())
+        .unwrap_or(false)
+    {
+        return Err(FetchError::Sensitive);
+    }
     Ok(Tweet::from_syndication_json(&text).map_err(FetchError::Json)?)
 }
 

crates/x-media/src/site/twitter/mod.rs

@@ -1,3 +1,4 @@
+mod auth;
 mod interface;
 mod model;