Various changes

server-rs/src/og_middleware.rs

@@ -0,0 +1,65 @@
+use std::sync::Arc;
+
+use axum::body::Body;
+use axum::extract::Request;
+use axum::http::header;
+use axum::middleware::Next;
+use axum::response::Response;
+use regex::Regex;
+
+use crate::state::AppState;
+
+pub async fn og_middleware(request: Request, next: Next) -> Response {
+    // Capture the query string before passing the request through
+    let query_string = request.uri().query().unwrap_or("").to_string();
+
+    // Get state from extensions
+    let state = request.extensions().get::<Arc<AppState>>().cloned();
+
+    let response = next.run(request).await;
+
+    let content_type = response
+        .headers()
+        .get(header::CONTENT_TYPE)
+        .and_then(|val| val.to_str().ok())
+        .unwrap_or("");
+
+    if !content_type.contains("text/html") {
+        return response;
+    }
+
+    let state = match state {
+        Some(st) => st,
+        None => return response,
+    };
+
+    let index_html = match &state.index_html {
+        Some(html) => html,
+        None => return response,
+    };
+
+    // Build OG-injected HTML
+    let og_image_url = if query_string.is_empty() {
+        format!("{}/api/og-image", state.public_url)
+    } else {
+        format!("{}/api/og-image?{}", state.public_url, query_string)
+    };
+
+    let og_tags = format!(
+        r#"<title>Narrowit</title>
+<meta property="og:title" content="Narrowit — UK Property Map" />
+<meta property="og:description" content="Interactive property data visualization for England &amp; Wales" />
+<meta property="og:image" content="{og_image_url}" />
+<meta property="og:image:width" content="1200" />
+<meta property="og:image:height" content="630" />
+<meta name="twitter:card" content="summary_large_image" />
+<meta name="twitter:image" content="{og_image_url}" />"#
+    );
+
+    // Replace the <title> tag with title + OG meta tags
+    let re = Regex::new(r"<title>Narrowit</title>").unwrap();
+    let html = re.replace(index_html, og_tags.as_str()).to_string();
+
+    let (parts, _body) = response.into_parts();
+    Response::from_parts(parts, Body::from(html))
+}