Redirects need to be cached separately

[lukaslihotzki-f]

http-cache-reqwest does not cache redirects correctly. Redirects are followed by reqwest invisible to the http-cache, and then the final response of the redirect chain is cached for the original request. The following patch demonstrates this issue. The redirect from / to /final is uncachable, but the cache stores the cachable response for /final as /.

diff --git a/http-cache-reqwest/examples/reqwest_basic.rs b/http-cache-reqwest/examples/reqwest_basic.rs
index 1bc25d3..427ed44 100644
--- a/http-cache-reqwest/examples/reqwest_basic.rs
+++ b/http-cache-reqwest/examples/reqwest_basic.rs
@@ -7,13 +7,24 @@ use http_cache_reqwest::{CACacheManager, Cache};
 use reqwest::Client;
 use reqwest_middleware::ClientBuilder;
 use std::time::Instant;
-use wiremock::{matchers::method, Mock, MockServer, ResponseTemplate};
+use wiremock::{matchers::path, Mock, MockServer, ResponseTemplate};

 #[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
     // Setup mock server with cacheable response
     let mock_server = MockServer::start().await;
-    Mock::given(method("GET"))
+    Mock::given(path("/"))
+        .respond_with(
+            ResponseTemplate::new(307)
+                .set_body_string("Hello from cached response!")
+                .append_header("cache-control", "no-cache, no-store")
+                .append_header("location", "/final")
+                .append_header("content-type", "text/plain"),
+        )
+        .mount(&mock_server)
+        .await;
+
+    Mock::given(path("/final"))
         .respond_with(
             ResponseTemplate::new(200)
                 .set_body_string("Hello from cached response!")

[06chaynes]

Good find. I don't think there is a workaround for this on my end, for now the best I have for users is to:

1. Disable automatic redirects
2. Manually handle redirects in their application code
3. Make separate requests for each hop in the redirect chain

I will keep an eye on this, hopefully your issue is addressed on the middleware end.

[06chaynes]

http-cache-reqwest v1.0.0-alpha.8 includes an optional integration with middlewest, which is a fork of reqwest-middleware I recently published. I added optional redirect handling logic that fixes things on the caching end and addressed a few more outstanding items. Not the ideal solution but its an option until such changes make it back upstream (if any do).