From 9b5a8321f0a723cc2a4357fd10e04e2ee770a11e Mon Sep 17 00:00:00 2001
From: Jack Platten <jack@platten.me>
Date: Tue, 10 Mar 2026 11:47:18 -0700
Subject: [PATCH] backend cachebusting

---
 src/main.rs       | 55 ++++++++++++++++++++++++++++++++++++-----------
 src/rss_poller.rs | 55 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 98 insertions(+), 12 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index 33d4ff3..31c1c92 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -57,26 +57,57 @@ fn index() -> &'static str {
 
 #[get("/slug/<slug>")]
 async fn post_meta(mut db: Connection<Comments>, slug: &str) -> Option<Value> {
-    sqlx::query("SELECT * FROM posts WHERE slug = $1")
+    let db_result = sqlx::query("SELECT * FROM posts WHERE slug = $1")
         .bind(slug)
         .fetch_one(&mut **db)
-        .await
-        .map(|row| {
+        .await;
+
+    match db_result {
+        Ok(row) => {
             let meta = Meta {
                 id: row.get(0),
                 slug: row.get(1),
                 rkey: row.get(2),
                 time_us: row.get(3),
             };
-
-            json![{
-                "status" : "success",
-                "data": {
-                    "post": meta
-                }
-            }]
-        })
-        .ok()
+            Some(json![{
+                "status": "success",
+                "data": {"post": meta}
+            }])
+        }
+        Err(_) => {
+            // Not in DB — check the live RSS feed
+            let (rkey, time_us) = rss_poller::lookup_slug_in_rss(slug).await?;
+
+            // Insert; ignore conflicts in case the background poller raced us
+            let _ = sqlx::query(
+                "INSERT INTO posts (slug, rkey, time_us) VALUES ($1, $2, $3) ON CONFLICT (slug) DO NOTHING"
+            )
+            .bind(slug)
+            .bind(&rkey)
+            .bind(&time_us)
+            .execute(&mut **db)
+            .await;
+
+            sqlx::query("SELECT * FROM posts WHERE slug = $1")
+                .bind(slug)
+                .fetch_one(&mut **db)
+                .await
+                .map(|row| {
+                    let meta = Meta {
+                        id: row.get(0),
+                        slug: row.get(1),
+                        rkey: row.get(2),
+                        time_us: row.get(3),
+                    };
+                    json![{
+                        "status": "success",
+                        "data": {"post": meta}
+                    }]
+                })
+                .ok()
+        }
+    }
 }
 
 #[get("/slug")]
diff --git a/src/rss_poller.rs b/src/rss_poller.rs
index d08765a..998ea07 100644
--- a/src/rss_poller.rs
+++ b/src/rss_poller.rs
@@ -143,6 +143,61 @@ async fn poll_rss(pool: &sqlx::Pool<sqlx::Postgres>, config: &PollerConfig) -> R
     Ok(())
 }
 
+/// Look up a specific slug in the RSS feed on demand.
+/// Returns `(rkey, time_us)` if the slug is found, `None` otherwise.
+pub async fn lookup_slug_in_rss(slug: &str) -> Option<(String, String)> {
+    let config = match Config::figment().extract::<PollerConfig>() {
+        Ok(c) => c,
+        Err(e) => {
+            log::error!("[rss] Failed to load config: {}", e);
+            return None;
+        }
+    };
+
+    let channel = match fetch_rss(&config.poster_handle).await {
+        Ok(c) => c,
+        Err(e) => {
+            log::error!("[rss] Failed to fetch RSS for on-demand lookup: {}", e);
+            return None;
+        }
+    };
+
+    for item in channel.items() {
+        let guid = match item.guid() {
+            Some(g) => g.value(),
+            None => continue,
+        };
+
+        let rkey = match extract_rkey(guid) {
+            Some(r) => r,
+            None => continue,
+        };
+
+        let description = match item.description() {
+            Some(d) => d,
+            None => continue,
+        };
+
+        let urls = find_blog_urls(description, &config.target_emoji, &config.blog_domain);
+
+        for url in &urls {
+            if let Some(found_slug) = extract_slug_from_url(url, &config.blog_domain) {
+                if found_slug == slug {
+                    let time_us = item
+                        .pub_date()
+                        .and_then(|date_str| chrono::DateTime::parse_from_rfc2822(date_str).ok())
+                        .map(|dt| dt.timestamp_micros().to_string())
+                        .unwrap_or_else(|| chrono::Utc::now().timestamp_micros().to_string());
+                    log::info!("[rss] On-demand lookup found slug={} rkey={}", slug, rkey);
+                    return Some((rkey, time_us));
+                }
+            }
+        }
+    }
+
+    None
+}
+
 /// Background task that polls RSS every 15 minutes
 pub async fn rss_polling_task(pool: sqlx::Pool<sqlx::Postgres>) {
     let config = match Config::figment().extract::<PollerConfig>() {
-- 
2.51.2