Remove mutation from default_config and set default log_level to off

Cargo.lock

@@ -317,6 +317,7 @@ dependencies = [
  "image",
  "jsonwebtoken",
  "lru-cache",
+ "maplit",
  "num_cpus",
  "opentelemetry",
  "opentelemetry-jaeger",

Cargo.toml

@@ -84,6 +84,7 @@ hmac = "0.11.0"
 sha-1 = "0.9.8"
 # used for conduit's CLI and admin room command parsing
 clap = { version = "3.0.10", default-features = false, features = ["std", "derive"] }
+maplit = "1.0.2"
 
 [target.'cfg(not(target_env = "msvc"))'.dependencies]
 tikv-jemalloc-ctl = { version = "0.4.2", features = ['use_std'] }

src/main.rs

@@ -9,6 +9,7 @@
 
 use std::sync::Arc;
 
+use maplit::hashset;
 use opentelemetry::trace::{FutureExt, Tracer};
 use rocket::{
     catch, catchers,
@@ -292,28 +293,26 @@ fn bad_json_catcher() -> Result<()> {
 }
 
 fn default_config() -> rocket::Config {
-    let mut config = rocket::Config::release_default();
-
-    {
-        let mut shutdown = &mut config.shutdown;
-
-        #[cfg(unix)]
-        {
-            use rocket::config::Sig;
-
-            shutdown.signals.insert(Sig::Term);
-            shutdown.signals.insert(Sig::Int);
-        }
+    use rocket::config::{LogLevel, Shutdown, Sig};
 
+    rocket::Config {
+        // Disable rocket's logging to get only tracing-subscriber's log output
+        log_level: LogLevel::Off,
+        shutdown: Shutdown {
             // Once shutdown is triggered, this is the amount of seconds before rocket
             // will forcefully start shutting down connections, this gives enough time to /sync
             // requests and the like (which havent gotten the memo, somehow) to still complete gracefully.
-        shutdown.grace = 35;
+            grace: 35,
 
             // After the grace period, rocket starts shutting down connections, and waits at least this
             // many seconds before forcefully shutting all of them down.
-        shutdown.mercy = 10;
-    }
+            mercy: 10,
 
-    config
+            #[cfg(unix)]
+            signals: hashset![Sig::Term, Sig::Int],
+
+            ..Shutdown::default()
+        },
+        ..rocket::Config::release_default()
+    }
 }