From c36b6edbfb2fdbdddf5b9602c6c791e68d3128bb Mon Sep 17 00:00:00 2001
From: Stefano Pigozzi <me@steffo.eu>
Date: Fri, 15 Nov 2024 18:12:13 +0100
Subject: [PATCH] `webfinger`: Serve XRD and JRD responses

---
 acrate-webfinger/Cargo.toml   |  2 ++
 acrate-webfinger/src/route.rs | 47 ++++++++++++++++++++++++++---------
 2 files changed, 37 insertions(+), 12 deletions(-)

diff --git a/acrate-webfinger/Cargo.toml b/acrate-webfinger/Cargo.toml
index f74ff6b..5bb8042 100644
--- a/acrate-webfinger/Cargo.toml
+++ b/acrate-webfinger/Cargo.toml
@@ -12,5 +12,7 @@ axum-extra = { version = "0.9.4", features = ["query"] }
 log = "0.4.22"
 micronfig = "0.3.0"
 pretty_env_logger = "0.5.0"
+quick-xml = { version = "0.37.0", features = ["serialize"] }
 serde = { version = "1.0.215", features = ["derive"] }
+serde_json = "1.0.132"
 tokio = { version = "1.41.1", features = ["macros", "net", "rt-multi-thread"] }
diff --git a/acrate-webfinger/src/route.rs b/acrate-webfinger/src/route.rs
index dc98106..a94ec6e 100644
--- a/acrate-webfinger/src/route.rs
+++ b/acrate-webfinger/src/route.rs
@@ -1,5 +1,4 @@
-use axum::body::Body;
-use axum::http::{HeaderMap, HeaderValue, StatusCode};
+use axum::http::{HeaderMap, Response, StatusCode};
 use axum_extra::extract::Query;
 use serde::Deserialize;
 use acrate_core::diesel_async::{AsyncConnection, AsyncPgConnection};
@@ -9,7 +8,7 @@ use crate::config;
 
 #[derive(Debug, Clone, Deserialize)]
 pub struct WebfingerQuery {
-	pub resource: String,
+	pub resource: Option<String>,
 	
 	#[serde(default)]
 	pub rel: Vec<String>,
@@ -21,9 +20,10 @@ const WEBFINGER_DOC: &str = "/.well-known/webfinger";
 pub async fn webfinger_handler(
 	Query(WebfingerQuery {resource, rel}): Query<WebfingerQuery>,
 	headers: HeaderMap,
-) -> Result<(Body, HeaderMap), StatusCode> {
+) -> Result<Response<String>, StatusCode> {
 	log::info!("Handling a WebFinger request!");
 	
+	let resource = resource.unwrap_or_else(|| "".to_string());
 	log::debug!("Resource is: {resource:#?}");
 	
 	log::debug!("Rel is: {rel:#?}");
@@ -36,7 +36,7 @@ pub async fn webfinger_handler(
 		.to_string();
 	log::debug!("Accept is: {accept:#?}");
 	
-	let mut response_headers = HeaderMap::new();
+	let mut response = Response::new("".to_string());
 	
 	let mut conn = AsyncPgConnection::establish(config::ACRATE_WEBFINGER_DATABASE_URL())
 		.await
@@ -54,11 +54,19 @@ pub async fn webfinger_handler(
 		.await
 		.map_err(|_| StatusCode::INTERNAL_SERVER_ERROR)?;
 	
-	for mime in accept.split(", ") {
-		response_headers.insert("Content-Type", mime.parse().unwrap());
-		
+	for mime in accept.split(",") {
+		{
+			let headers = response.headers_mut();
+			headers.insert("Content-Type", mime.parse().unwrap());
+		}
+
+		let (mime, _params) = match mime.trim().split_once(";") {
+			Some((mime, params)) => (mime, Some(params)),
+			None => (mime, None),
+		};
+
 		match mime {
-			"application/json" | "application/jrd+json" => {
+			"*/*" | "application/json" | "application/jrd+json" => {
 				let subject = Some(resource);
 				
 				let aliases = aliases
@@ -90,9 +98,15 @@ pub async fn webfinger_handler(
 					links,
 				};
 				
-				let body = rd.
+				let json = serde_json::to_string_pretty(&rd)
+					.map_err(|_| StatusCode::INTERNAL_SERVER_ERROR)?;
 				
-				return Ok(rd, response_headers)
+				{
+					let body = response.body_mut();
+					body.push_str(&json);
+				}
+				
+				return Ok(response)
 			},
 			"application/xml" | "application/xrd+xml" => {
 				let subject = Some(resource);
@@ -129,7 +143,16 @@ pub async fn webfinger_handler(
 					links,
 				};
 				
-				return Ok(StatusCode::OK)
+				let xml = quick_xml::se::to_string(&rd)
+					.map_err(|_| StatusCode::INTERNAL_SERVER_ERROR)?;
+				
+				{
+					let body = response.body_mut();
+					body.push_str("<?xml version='1.0' encoding='UTF-8'?>");
+					body.push_str(&xml);
+				}
+				
+				return Ok(response)
 			},
 			_ => {
 				continue;