fix: properly handle 416 in initial tail request

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "async_http_range_reader"
 authors = ["Bas Zalmstra <zalmstra.bas@gmail.com>"]
-version = "0.9.1"
+version = "0.9.2"
 edition = "2021"
 description = "A library for streaming reading of files over HTTP using range requests"
 license = "MIT"
@@ -15,7 +15,9 @@ http-content-range = "0.2.0"
 itertools = "0.13.0"
 bisection = "0.1.0"
 memmap2 = "0.9.0"
-reqwest = { version = "0.12.3", default-features = false, features = ["stream"] }
+reqwest = { version = "0.12.3", default-features = false, features = [
+  "stream",
+] }
 reqwest-middleware = "0.4.0"
 tokio = { version = "1.33.0", default-features = false }
 tokio-stream = { version = "0.1.14", features = ["sync"] }
@@ -24,10 +26,18 @@ thiserror = "1.0.50"
 tracing = "0.1.40"
 
 [dev-dependencies]
-axum = { version = "0.7.5", default-features = false, features = ["tokio", "http1"] }
-tokio = { version = "1.33.0", default-features = false, features = ["macros", "test-util"] }
+axum = { version = "0.7.5", default-features = false, features = [
+  "tokio",
+  "http1",
+] }
+tokio = { version = "1.33.0", default-features = false, features = [
+  "macros",
+  "test-util",
+] }
 tower-http = { version = "0.6.1", default-features = false, features = ["fs"] }
-async_zip = { version = "0.0.17", default-features = false, features = ["tokio"] }
+async_zip = { version = "0.0.17", default-features = false, features = [
+  "tokio",
+] }
 assert_matches = "1.5.0"
 rstest = { version = "0.23.0" }
 url = { version = "2.4.1" }

src/lib.rs

@@ -189,7 +189,14 @@ impl AsyncHttpRangeReader {
             .headers(extra_headers)
             .send()
             .await
-            .and_then(error_for_status)
+            .map_err(Arc::new)
+            .map_err(AsyncHttpRangeReaderError::HttpError)?;
+
+        if tail_response.status() == reqwest::StatusCode::RANGE_NOT_SATISFIABLE {
+            return Err(AsyncHttpRangeReaderError::HttpRangeRequestUnsupported);
+        }
+
+        let tail_response = error_for_status(tail_response)
             .map_err(Arc::new)
             .map_err(AsyncHttpRangeReaderError::HttpError)?;
         Ok(tail_response)
@@ -655,6 +662,11 @@ mod static_directory_server;
 #[cfg(test)]
 mod test {
     use super::*;
+    use axum::{
+        http::{HeaderMap as AxumHeaderMap, StatusCode as AxumStatusCode},
+        routing::get,
+        Router,
+    };
     use crate::static_directory_server::StaticDirectoryServer;
     use assert_matches::assert_matches;
     use async_zip::tokio::read::seek::ZipFileReader;
@@ -854,4 +866,33 @@ mod test {
             err, AsyncHttpRangeReaderError::HttpError(err) if err.status() == Some(StatusCode::NOT_FOUND)
         );
     }
+
+    #[tokio::test]
+    async fn test_negative_range_416_is_unsupported() {
+        async fn handler(headers: AxumHeaderMap) -> AxumStatusCode {
+            if headers.contains_key(reqwest::header::RANGE) {
+                AxumStatusCode::RANGE_NOT_SATISFIABLE
+            } else {
+                AxumStatusCode::OK
+            }
+        }
+
+        let app = Router::new().route("/", get(handler));
+        let listener = tokio::net::TcpListener::bind(("127.0.0.1", 0)).await.unwrap();
+        let addr = listener.local_addr().unwrap();
+        tokio::spawn(async move {
+            let _ = axum::serve(listener, app).await;
+        });
+
+        let err = AsyncHttpRangeReader::new(
+            Client::new(),
+            Url::parse(&format!("http://127.0.0.1:{}/", addr.port())).unwrap(),
+            CheckSupportMethod::NegativeRangeRequest(8192),
+            HeaderMap::default(),
+        )
+        .await
+        .expect_err("expected an unsupported range request error");
+
+        assert_matches!(err, AsyncHttpRangeReaderError::HttpRangeRequestUnsupported);
+    }
 }