feat: integrate feed_parser into Phase 1 pipeline with HTML fallback

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

backend/src/services/synthesis/mod.rs

@@ -12,7 +12,7 @@ use std::sync::atomic::{AtomicBool, Ordering};
 use std::sync::Arc;
 use std::time::Duration;
 
-use chrono::Utc;
+use chrono::{DateTime, Utc};
 use tokio::sync::watch;
 use uuid::Uuid;
 
@@ -27,6 +27,7 @@ use crate::services::encryption;
 use crate::services::llm::factory::create_provider;
 use crate::services::scraper;
 use crate::services::source_scraper;
+use crate::services::feed_parser;
 
 mod helpers;
 pub(crate) use helpers::{
@@ -189,23 +190,72 @@ pub async fn run_generation_inner(
                 &format!("Vague {}/{} : extraction des sources...", wave_idx + 1, total_waves),
                 pct as u8);
 
-            // 1a. Extract links from this wave's sources (all in parallel)
+            // 1a. Extract links from this wave's sources (RSS-first with HTML fallback)
             let mut wave_urls: Vec<(String, String)> = Vec::new();
+            let mut rss_updates: Vec<(Uuid, Option<String>, Option<DateTime<Utc>>)> = Vec::new();
             {
                 let mut join_set = tokio::task::JoinSet::new();
                 for source in wave_sources {
                     let client = state.http_client.clone();
+                    let source_id = source.id;
                     let source_url = source.url.clone();
                     let source_title = source.title.clone();
+                    let rss_url = source.rss_url.clone();
+                    let rss_discovered_at = source.rss_discovered_at;
                     let max_l = max_links;
                     join_set.spawn(async move {
-                        let links = source_scraper::extract_article_links(&client, &source_url, max_l).await;
-                        (source_url, source_title, links)
+                        // Try RSS feed first
+                        let feed_result = feed_parser::detect_and_parse_feed(
+                            &client,
+                            &source_url,
+                            rss_url.as_deref(),
+                            rss_discovered_at,
+                            max_l,
+                        ).await;
+
+                        match feed_result {
+                            feed_parser::FeedResult::Found { feed_url, entries }
+                                if entries.len() >= feed_parser::MIN_FEED_ENTRIES =>
+                            {
+                                let links: Vec<String> = entries.into_iter().map(|e| e.url).collect();
+                                tracing::info!(
+                                    source = %source_title,
+                                    feed = %feed_url,
+                                    links = links.len(),
+                                    "Extracted links from RSS feed"
+                                );
+                                // Signal RSS URL update if it changed
+                                let rss_changed = rss_url.as_deref() != Some(&feed_url);
+                                let rss_stale = rss_discovered_at
+                                    .map(|d| Utc::now().signed_duration_since(d).num_days() >= feed_parser::REDISCOVERY_DAYS)
+                                    .unwrap_or(true);
+                                let update = if rss_changed || rss_stale {
+                                    Some((source_id, Some(feed_url), Some(Utc::now())))
+                                } else {
+                                    None
+                                };
+                                (source_url, source_title, Ok(links), update)
+                            }
+                            _ => {
+                                // Fallback to HTML extraction
+                                let links = source_scraper::extract_article_links(&client, &source_url, max_l).await;
+                                // If we had a cached RSS URL but feed failed, clear it
+                                let update = if rss_url.is_some() {
+                                    Some((source_id, None, None))
+                                } else {
+                                    None
+                                };
+                                (source_url, source_title, links, update)
+                            }
+                        }
                     });
                 }
 
                 while let Some(join_result) = join_set.join_next().await {
-                    if let Ok((source_url, source_title, links_result)) = join_result {
+                    if let Ok((source_url, source_title, links_result, rss_update)) = join_result {
+                        if let Some(update) = rss_update {
+                            rss_updates.push(update);
+                        }
                         match links_result {
                             Ok(links) => {
                                 tracing::info!(source = %source_title, links = links.len(), "Extracted links from source");
@@ -223,6 +273,16 @@ pub async fn run_generation_inner(
                 }
             }
 
+            // Persist RSS URL updates (fire-and-forget)
+            for (source_id, new_rss_url, new_discovered_at) in rss_updates {
+                db::sources::update_source_rss(
+                    &state.pool,
+                    source_id,
+                    new_rss_url.as_deref(),
+                    new_discovered_at,
+                ).await.ok();
+            }
+
             // 1b. Filter against article history
             if settings.article_history_days > 0 && !wave_urls.is_empty() {
                 let hashes: Vec<String> = wave_urls.iter().map(|(url, _)| hash_article_url(url)).collect();