feat: add badge.svg

remote/cache-service/src/api.rs

@@ -18,6 +18,72 @@ static OPEN_PNG: &[u8] = include_bytes!("../assets/open.png");
 static CLOSED_PNG: &[u8] = include_bytes!("../assets/closed.png");
 static OFFLINE_PNG: &[u8] = include_bytes!("../assets/offline.png");
 
+const BADGE_LABEL: &str = "space";
+
+fn escape_xml(text: &str) -> String {
+    text.replace('&', "&")
+        .replace('<', "&lt;")
+        .replace('>', "&gt;")
+        .replace('"', "&quot;")
+        .replace('\'', "&apos;")
+}
+
+fn badge_color(status: DoorStatus) -> &'static str {
+    match status {
+        DoorStatus::Open => "#34a853",
+        DoorStatus::Closed => "#e05d44",
+        DoorStatus::Offline => "#9f9f9f",
+    }
+}
+
+fn badge_text_width(text: &str) -> usize {
+    text.chars().count() * 7 + 10
+}
+
+fn render_badge_svg(status: DoorStatus, summary: &str) -> String {
+    let message = status.as_str();
+    let label_width = badge_text_width(BADGE_LABEL);
+    let message_width = badge_text_width(message);
+    let total_width = label_width + message_width;
+    let label_center = label_width / 2;
+    let message_center = label_width + (message_width / 2);
+    let escaped_summary = escape_xml(summary);
+
+    format!(
+        concat!(
+            "<svg xmlns=\"http://www.w3.org/2000/svg\" width=\"{total_width}\" height=\"20\" role=\"img\" aria-label=\"{label}: {message}\">",
+            "<title>{summary}</title>",
+            "<linearGradient id=\"b\" x2=\"0\" y2=\"100%\">",
+            "<stop offset=\"0\" stop-color=\"#fff\" stop-opacity=\".7\"/>",
+            "<stop offset=\".1\" stop-opacity=\".1\"/>",
+            "<stop offset=\".9\" stop-opacity=\".3\"/>",
+            "<stop offset=\"1\" stop-opacity=\".5\"/>",
+            "</linearGradient>",
+            "<mask id=\"a\"><rect width=\"{total_width}\" height=\"20\" rx=\"3\" fill=\"#fff\"/></mask>",
+            "<g mask=\"url(#a)\">",
+            "<rect width=\"{label_width}\" height=\"20\" fill=\"#555\"/>",
+            "<rect x=\"{label_width}\" width=\"{message_width}\" height=\"20\" fill=\"{color}\"/>",
+            "<rect width=\"{total_width}\" height=\"20\" fill=\"url(#b)\"/>",
+            "</g>",
+            "<g fill=\"#fff\" text-anchor=\"middle\" font-family=\"Verdana,Geneva,DejaVu Sans,sans-serif\" font-size=\"11\">",
+            "<text x=\"{label_center}\" y=\"15\" fill=\"#010101\" fill-opacity=\".3\">{label}</text>",
+            "<text x=\"{label_center}\" y=\"14\">{label}</text>",
+            "<text x=\"{message_center}\" y=\"15\" fill=\"#010101\" fill-opacity=\".3\">{message}</text>",
+            "<text x=\"{message_center}\" y=\"14\">{message}</text>",
+            "</g></svg>",
+        ),
+        total_width = total_width,
+        label = BADGE_LABEL,
+        message = message,
+        summary = escaped_summary,
+        label_width = label_width,
+        message_width = message_width,
+        color = badge_color(status),
+        label_center = label_center,
+        message_center = message_center,
+    )
+}
+
 pub struct AppState {
     pub db: Arc<Mutex<rusqlite::Connection>>,
     pub client: reqwest::Client,
@@ -244,6 +310,35 @@ pub async fn get_image(State(state): State<Arc<AppState>>) -> Response {
         .into_response()
 }
 
+pub async fn get_badge(State(state): State<Arc<AppState>>) -> Response {
+    let db = state.db.clone();
+    let status = match tokio::task::spawn_blocking(move || {
+        let conn = db.blocking_lock();
+        db::get_status(&conn)
+    })
+    .await
+    .expect("db task panicked")
+    {
+        Ok(status) => status,
+        Err(e) => {
+            error!(error = %e, "failed to get status for badge");
+            return StatusCode::INTERNAL_SERVER_ERROR.into_response();
+        }
+    };
+
+    let summary = status_summary(status.status, status.since, status.last_checked, unix_now());
+    let badge = render_badge_svg(status.status, &summary);
+
+    (
+        [
+            (header::CONTENT_TYPE, "image/svg+xml; charset=utf-8"),
+            (header::CACHE_CONTROL, "public, max-age=5"),
+        ],
+        badge,
+    )
+        .into_response()
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -264,4 +359,15 @@ mod tests {
         assert!(summary.contains("Last checked"));
         assert!(summary.contains("55 seconds ago"));
     }
+
+    #[test]
+    fn render_badge_svg_includes_status_and_summary() {
+        let svg = render_badge_svg(DoorStatus::Offline, "Cache can't reach the space right now.");
+
+        assert!(svg.contains("aria-label=\"space: offline\""));
+        assert!(svg.contains(">space<"));
+        assert!(svg.contains(">offline<"));
+        assert!(svg.contains("Cache can&apos;t reach the space right now."));
+        assert!(svg.contains("#9f9f9f"));
+    }
 }

remote/cache-service/src/main.rs

@@ -127,6 +127,7 @@ async fn main() -> Result<()> {
         .route("/health", get(api::health))
         .route("/webhook", post(api::post_webhook))
         .route("/status", get(api::get_status))
+        .route("/badge.svg", get(api::get_badge))
         .route("/image", get(api::get_image))
         .route("/image/open.png", get(api::get_image_open))
         .route("/image/closed.png", get(api::get_image_closed))