FIX: Avoid stack overflow triggered by addition of new Actor::auth_error field by flattening out chained async API handler invocation. This avoids deep recursive .or_else() macro expansion of calls that pass the large Request value (of which Actor is part) resulting in stack overflow. This fix also removes the need for the boosted recursion_limit compiler setting.

src/bin/krill.rs

@@ -1,11 +1,3 @@
-// Added so that the call chain from http/auth.rs through to Authorizer doesn't
-// exceed the recursion limit within future macro expansion. Possibly related to
-// this:
-//   "Note that select! relies on proc-macro-hack, and may require to set the
-//    compiler's recursion limit very high, e.g. #![recursion_limit="1024"]."
-// From: https://docs.rs/futures/0.3.6/futures/macro.select.html
-#![recursion_limit = "155"]
-
 extern crate krill;
 
 use std::env;

src/bin/krillc.rs

@@ -1,5 +1,3 @@
-#![recursion_limit = "155"]
-
 extern crate krill;
 
 use krill::cli::options::Options;

src/bin/krillpubc.rs

@@ -1,5 +1,3 @@
-#![recursion_limit = "155"]
-
 extern crate krill;
 
 use krill::cli::options::KrillPubcOptions;

src/bin/krillpubd.rs

@@ -1,5 +1,3 @@
-#![recursion_limit = "155"]
-
 extern crate krill;
 
 use std::sync::Arc;

src/daemon/http/server.rs

@@ -201,20 +201,29 @@ async fn map_requests(req: hyper::Request<hyper::Body>, state: State) -> Result<
     // just make the trace log unusable.
     let logger = ApiCallLogger::new(&req);
 
-    let res = api(req)
-        .or_else(auth)
-        .or_else(health)
-        .or_else(metrics)
-        .or_else(stats)
-        .or_else(rfc8181)
-        .or_else(rfc6492)
-        .or_else(statics)
-        .or_else(ta)
-        .or_else(rrdp)
-        .or_else(testbed)
-        .or_else(render_not_found)
-        .map_err(|_| Error::custom("should have received not found response"))
-        .await;
+    // We used to use .or_else() here but that causes a large recursive call
+    // tree due to these calls being to async functions, large enough with the
+    // given Request object passed each time that it eventually resulted in
+    // stack overflow. By doing it by hand like this we avoid the use of the
+    // macros that cause the recursion. We could also look at putting less data
+    // on the stack.
+    let mut res = api(req).await;
+    if let Err(req) = res { res = auth(req).await; }
+    if let Err(req) = res { res = health(req).await; }
+    if let Err(req) = res { res = metrics(req).await; }
+    if let Err(req) = res { res = stats(req).await; }
+    if let Err(req) = res { res = rfc8181(req).await; }
+    if let Err(req) = res { res = rfc6492(req).await; }
+    if let Err(req) = res { res = statics(req).await; }
+    if let Err(req) = res { res = ta(req).await; }
+    if let Err(req) = res { res = rrdp(req).await; }
+    if let Err(req) = res { res = testbed(req).await; }
+    if let Err(req) = res { res = render_not_found(req).await; }
+
+    let res = match res {
+        Ok(res) => Ok(res),
+        Err(_) => Err(Error::custom("should have received not found response")),
+    };
 
     // Augment the response with any updated auth details that were determined
     // above.

src/lib.rs

@@ -1,5 +1,3 @@
-#![recursion_limit = "155"]
-
 extern crate base64;
 #[macro_use]
 extern crate bcder;

tests/functional.rs

@@ -1,7 +1,5 @@
 //! Perform functional tests on a Krill instance, using the API
 //!
-#![recursion_limit = "155"]
-
 use std::fs;
 use std::str::FromStr;
 use std::time::Duration;

tests/history.rs

@@ -1,6 +1,3 @@
-#![type_length_limit = "5000000"]
-#![recursion_limit = "155"]
-
 extern crate krill;
 
 /// This tests regressions for the Command history and details as exposed through the

tests/multi_user_config_file.rs

@@ -1,5 +1,3 @@
-#![recursion_limit = "155"]
-
 #[cfg(feature = "ui-tests")]
 mod ui;
 

tests/multi_user_config_file_with_ta.rs

@@ -1,5 +1,3 @@
-#![recursion_limit = "155"]
-
 #[cfg(feature = "ui-tests")]
 mod ui;
 

tests/multi_user_master_token.rs

@@ -1,5 +1,3 @@
-#![recursion_limit = "155"]
-
 #[cfg(feature = "ui-tests")]
 mod ui;
 

tests/multi_user_openid_connect.rs

@@ -1,5 +1,3 @@
-#![recursion_limit = "155"]
-
 #[cfg(feature = "ui-tests")]
 mod ui;
 

tests/multi_user_team_policy.rs

@@ -1,5 +1,3 @@
-#![recursion_limit = "155"]
-
 #[cfg(feature = "ui-tests")]
 mod ui;
 

tests/testbed.rs

@@ -1,5 +1,4 @@
 #![type_length_limit = "5000000"]
-#![recursion_limit = "155"]
 
 extern crate krill;