rss and atom feeds

cruciverb-server/src/feeds.rs

@@ -0,0 +1,158 @@
+use std::sync::Arc;
+
+use axum::extract::{Query, State};
+use axum::http::header;
+use axum::response::{IntoResponse, Response};
+
+use crate::state::AppState;
+
+#[derive(serde::Deserialize)]
+pub struct FeedQuery {
+    pub preset: Option<String>,
+}
+
+pub async fn atom_feed(
+    State(state): State<Arc<AppState>>,
+    Query(q): Query<FeedQuery>,
+) -> Response {
+    let entries = get_recent_dailies(&state, q.preset.as_deref()).await;
+    let feed = build_atom(&entries);
+    ([(header::CONTENT_TYPE, "application/atom+xml; charset=utf-8")], feed).into_response()
+}
+
+pub async fn rss_feed(
+    State(state): State<Arc<AppState>>,
+    Query(q): Query<FeedQuery>,
+) -> Response {
+    let entries = get_recent_dailies(&state, q.preset.as_deref()).await;
+    let feed = build_rss(&entries);
+    ([(header::CONTENT_TYPE, "application/rss+xml; charset=utf-8")], feed).into_response()
+}
+
+pub async fn json_feed(
+    State(state): State<Arc<AppState>>,
+    Query(q): Query<FeedQuery>,
+) -> Response {
+    let entries = get_recent_dailies(&state, q.preset.as_deref()).await;
+    let feed = build_json_feed(&entries);
+    ([(header::CONTENT_TYPE, "application/feed+json; charset=utf-8")], feed).into_response()
+}
+
+struct FeedEntry {
+    date: String,
+    preset: String,
+    short_id: String,
+    width: i64,
+    height: i64,
+}
+
+async fn get_recent_dailies(state: &AppState, preset_filter: Option<&str>) -> Vec<FeedEntry> {
+    let dbi = state.db.lock().await;
+    let (query, param): (String, Option<String>) = if let Some(preset) = preset_filter {
+        ("SELECT daily_date, preset, short_id, width, height FROM puzzles WHERE daily_date IS NOT NULL AND preset = ?1 ORDER BY daily_date DESC LIMIT 14".into(), Some(preset.to_string()))
+    } else {
+        ("SELECT daily_date, preset, short_id, width, height FROM puzzles WHERE daily_date IS NOT NULL ORDER BY daily_date DESC LIMIT 28".into(), None)
+    };
+
+    let mut stmt = dbi.db.prepare(&query).unwrap();
+    let rows = if let Some(p) = &param {
+        stmt.query_map(rusqlite::params![p], |row| {
+            Ok(FeedEntry {
+                date: row.get::<_, String>(0)?,
+                preset: row.get::<_, String>(1)?,
+                short_id: row.get::<_, String>(2)?,
+                width: row.get::<_, i64>(3)?,
+                height: row.get::<_, i64>(4)?,
+            })
+        }).unwrap().filter_map(|r| r.ok()).collect()
+    } else {
+        stmt.query_map([], |row| {
+            Ok(FeedEntry {
+                date: row.get::<_, String>(0)?,
+                preset: row.get::<_, String>(1)?,
+                short_id: row.get::<_, String>(2)?,
+                width: row.get::<_, i64>(3)?,
+                height: row.get::<_, i64>(4)?,
+            })
+        }).unwrap().filter_map(|r| r.ok()).collect()
+    };
+    rows
+}
+
+fn build_atom(entries: &[FeedEntry]) -> String {
+    let mut xml = String::from(r#"<?xml version="1.0" encoding="UTF-8"?>
+<feed xmlns="http://www.w3.org/2005/Atom">
+  <title>cruciverb daily puzzles</title>
+  <id>urn:cruciverb:daily</id>
+  <updated>"#);
+
+    if let Some(e) = entries.first() {
+        xml.push_str(&format!("{}T00:00:00Z", e.date));
+    }
+    xml.push_str("</updated>\n");
+
+    for e in entries {
+        xml.push_str(&format!(
+            r#"  <entry>
+    <title>cruciverb {} - {} - {}x{}</title>
+    <id>urn:cruciverb:{}-{}</id>
+    <link href="/p/{}" />
+    <published>{}T00:00:00Z</published>
+    <summary>{}x{} {} crossword puzzle</summary>
+  </entry>
+"#,
+            e.preset, e.date, e.width, e.height,
+            e.preset, e.date,
+            e.short_id,
+            e.date,
+            e.width, e.height, e.preset,
+        ));
+    }
+    xml.push_str("</feed>\n");
+    xml
+}
+
+fn build_rss(entries: &[FeedEntry]) -> String {
+    let mut xml = String::from(r#"<?xml version="1.0" encoding="UTF-8"?>
+<rss version="2.0">
+<channel>
+  <title>cruciverb daily puzzles</title>
+  <description>daily crossword puzzles</description>
+"#);
+
+    for e in entries {
+        xml.push_str(&format!(
+            r#"  <item>
+    <title>cruciverb {} - {} - {}x{}</title>
+    <link>/p/{}</link>
+    <guid>cruciverb-{}-{}</guid>
+    <description>{}x{} {} crossword puzzle</description>
+  </item>
+"#,
+            e.preset, e.date, e.width, e.height,
+            e.short_id,
+            e.preset, e.date,
+            e.width, e.height, e.preset,
+        ));
+    }
+    xml.push_str("</channel>\n</rss>\n");
+    xml
+}
+
+fn build_json_feed(entries: &[FeedEntry]) -> String {
+    let items: Vec<serde_json::Value> = entries.iter().map(|e| {
+        serde_json::json!({
+            "id": format!("cruciverb-{}-{}", e.preset, e.date),
+            "title": format!("cruciverb {} - {} - {}x{}", e.preset, e.date, e.width, e.height),
+            "url": format!("/p/{}", e.short_id),
+            "content_text": format!("{}x{} {} crossword puzzle", e.width, e.height, e.preset),
+            "date_published": format!("{}T00:00:00Z", e.date),
+        })
+    }).collect();
+
+    serde_json::json!({
+        "version": "https://jsonfeed.org/version/1.1",
+        "title": "cruciverb daily puzzles",
+        "items": items,
+    }).to_string()
+}