From 7aa5a6738cebd450bb6909bd2d8a392eb0443206 Mon Sep 17 00:00:00 2001
From: Till Wegmueller <toasterson@gmail.com>
Date: Fri, 3 Apr 2026 19:30:26 +0200
Subject: [PATCH] feat: add host-meta endpoint with domain-aware XRD response

---
 src/handler/host_meta.rs | 45 +++++++++++++++++++++++++++++++++
 src/handler/mod.rs       |  2 ++
 tests/test_host_meta.rs  | 54 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 101 insertions(+)
 create mode 100644 src/handler/host_meta.rs
 create mode 100644 tests/test_host_meta.rs

diff --git a/src/handler/host_meta.rs b/src/handler/host_meta.rs
new file mode 100644
index 0000000..07f4b9f
--- /dev/null
+++ b/src/handler/host_meta.rs
@@ -0,0 +1,45 @@
+use axum::extract::State;
+use axum_extra::extract::Host;
+use axum::http::header;
+use axum::response::{IntoResponse, Response};
+use axum::routing::get;
+use axum::Router;
+use sea_orm::*;
+
+use crate::entity::domains;
+use crate::error::{AppError, AppResult};
+use crate::state::AppState;
+
+async fn host_meta(
+    State(state): State<AppState>,
+    Host(hostname): Host,
+) -> AppResult<Response> {
+    // Strip port if present
+    let domain = hostname.split(':').next().unwrap_or(&hostname);
+
+    // Check this domain is registered and verified
+    let _domain = domains::Entity::find()
+        .filter(domains::Column::Domain.eq(domain))
+        .filter(domains::Column::Verified.eq(true))
+        .one(&state.db)
+        .await?
+        .ok_or(AppError::NotFound)?;
+
+    let base_url = &state.settings.server.base_url;
+    let xrd = format!(
+        r#"<?xml version="1.0" encoding="UTF-8"?>
+<XRD xmlns="http://docs.oasis-open.org/ns/xri/xrd-1.0">
+  <Link rel="lrdd" type="application/jrd+json" template="{base_url}/.well-known/webfinger?resource={{uri}}" />
+</XRD>"#
+    );
+
+    Ok((
+        [(header::CONTENT_TYPE, "application/xrd+xml; charset=utf-8")],
+        xrd,
+    )
+        .into_response())
+}
+
+pub fn router() -> Router<AppState> {
+    Router::new().route("/.well-known/host-meta", get(host_meta))
+}
diff --git a/src/handler/mod.rs b/src/handler/mod.rs
index 1c09ae5..cf46fd5 100644
--- a/src/handler/mod.rs
+++ b/src/handler/mod.rs
@@ -1,4 +1,5 @@
 mod health;
+mod host_meta;
 mod webfinger;
 
 use axum::Router;
@@ -7,6 +8,7 @@ use crate::state::AppState;
 pub fn router(state: AppState) -> Router {
     Router::new()
         .merge(webfinger::router())
+        .merge(host_meta::router())
         .merge(health::router())
         .with_state(state)
 }
diff --git a/tests/test_host_meta.rs b/tests/test_host_meta.rs
new file mode 100644
index 0000000..15831e7
--- /dev/null
+++ b/tests/test_host_meta.rs
@@ -0,0 +1,54 @@
+mod common;
+
+use axum_test::TestServer;
+use webfingerd::handler;
+
+#[tokio::test]
+async fn test_host_meta_returns_xrd_for_known_domain() {
+    let state = common::test_state().await;
+
+    // Seed a verified domain in DB
+    use sea_orm::ActiveModelTrait;
+    use sea_orm::Set;
+    use webfingerd::entity::domains;
+
+    let domain = domains::ActiveModel {
+        id: Set(uuid::Uuid::new_v4().to_string()),
+        domain: Set("example.com".into()),
+        owner_token_hash: Set("hash".into()),
+        registration_secret: Set("secret".into()),
+        challenge_type: Set("dns-01".into()),
+        challenge_token: Set(None),
+        verified: Set(true),
+        created_at: Set(chrono::Utc::now().naive_utc()),
+        verified_at: Set(Some(chrono::Utc::now().naive_utc())),
+    };
+    domain.insert(&state.db).await.unwrap();
+
+    let app = handler::router(state);
+    let server = TestServer::new(app);
+
+    let response = server
+        .get("/.well-known/host-meta")
+        .add_header("Host", "example.com")
+        .await;
+
+    response.assert_status_ok();
+    let body = response.text();
+    assert!(body.contains("application/jrd+json") || body.contains("XRD"));
+    assert!(body.contains("/.well-known/webfinger"));
+}
+
+#[tokio::test]
+async fn test_host_meta_returns_404_for_unknown_domain() {
+    let state = common::test_state().await;
+    let app = handler::router(state);
+    let server = TestServer::new(app);
+
+    let response = server
+        .get("/.well-known/host-meta")
+        .add_header("Host", "unknown.example.com")
+        .await;
+
+    response.assert_status_not_found();
+}