send content-range on invalid range error

src/api/api_server.rs

@@ -65,10 +65,15 @@ async fn handler(
 		}
 		Err(e) => {
 			let body: Body = Body::from(e.aws_xml(&garage.config.s3_api.s3_region, uri.path()));
-			let http_error = Response::builder()
+			let mut http_error_builder = Response::builder()
 				.status(e.http_status_code())
-				.header("Content-Type", "application/xml")
-				.body(body)?;
+				.header("Content-Type", "application/xml");
+
+			if let Some(header_map) = http_error_builder.headers_mut() {
+				e.add_headers(header_map)
+			}
+
+			let http_error = http_error_builder.body(body)?;
 
 			if e.http_status_code().is_server_error() {
 				warn!("Response: error {}, {}", e.http_status_code(), e);

src/api/error.rs

@@ -1,5 +1,8 @@
+use std::convert::TryInto;
+
 use err_derive::Error;
-use hyper::StatusCode;
+use hyper::header::HeaderValue;
+use hyper::{HeaderMap, StatusCode};
 
 use garage_util::error::Error as GarageError;
 
@@ -57,7 +60,7 @@ pub enum Error {
 
 	/// The client sent a range header with invalid value
 	#[error(display = "Invalid HTTP range: {:?}", _0)]
-	InvalidRange(#[error(from)] http_range::HttpRangeParseError),
+	InvalidRange(#[error(from)] (http_range::HttpRangeParseError, u64)),
 
 	/// The client sent an invalid request
 	#[error(display = "Bad request: {}", _0)]
@@ -128,6 +131,21 @@ impl Error {
 			.into()
 		})
 	}
+
+	pub fn add_headers(&self, header_map: &mut HeaderMap<HeaderValue>) {
+		use hyper::header;
+		match self {
+			Error::InvalidRange((_, len)) => {
+				header_map.append(
+					header::CONTENT_RANGE,
+					format!("bytes */{}", len)
+						.try_into()
+						.expect("header value only contain ascii"),
+				);
+			}
+			_ => (),
+		}
+	}
 }
 
 /// Trait to map error to the Bad Request error code

src/api/s3_get.rs

@@ -156,7 +156,8 @@ pub async fn handle_get(
 	let range = match req.headers().get("range") {
 		Some(range) => {
 			let range_str = range.to_str()?;
-			let mut ranges = http_range::HttpRange::parse(range_str, last_v_meta.size)?;
+			let mut ranges = http_range::HttpRange::parse(range_str, last_v_meta.size)
+				.map_err(|e| (e, last_v_meta.size))?;
 			if ranges.len() > 1 {
 				// garage does not support multi-range requests yet, so we respond with the entire
 				// object when multiple ranges are requested