blobs/get_blob: error on status != OK

Before this change even error codes would be treated as success and the
body would contain the HTML formatted error message passed through to
the caller.

src/v2/blobs.rs

@@ -53,19 +53,22 @@ impl Client {
             .send()
             .inspect(|res| trace!("Blob GET result: {:?}", res.status()))
             .and_then(|mut res| {
-                let body = std::mem::replace(res.body_mut(), reqwest::async::Decoder::empty());
-                body.concat2()
+                let body =
+                    std::mem::replace(res.body_mut(), reqwest::async::Decoder::empty()).concat2();
+                body.join(futures::future::ok(res))
             }).map_err(|e| Error::from(format!("{}", e)))
-            .and_then(|body| {
-                let mut cursor = std::io::Cursor::new(body);
-                let mut buf = Vec::new();
-                use std::io::Read;
-                match cursor.read_to_end(&mut buf) {
-                    Ok(size) => {
-                        trace!("Received {} bytes from blob", size);
-                        Ok(buf)
+            .and_then(|(body, res)| {
+                let body_vec = body.to_vec();
+                let len = body_vec.len();
+                match res.status() {
+                    StatusCode::OK => {
+                        trace!("Received {} bytes from blob", len);
+                        Ok(body_vec)
                     }
-                    Err(e) => Err(Error::from(format!("{}", e))),
+                    status => Err(Error::from(format!(
+                        "GET request failed with status '{}' and body of size {}: {:#?}",
+                        status, len, body_vec
+                    ))),
                 }
             });
         Box::new(fres)