Create new Open ID client if old client is older than 60s (#1226)

This PR adds an explicit lifetime to the Open ID connection, and if the
connection has existed for more than 60 seconds, it will initialise a new
connection in order to pick up possible configuration changes at the provider.

src/daemon/auth/providers/openid_connect/provider.rs

@@ -33,7 +33,8 @@ use std::{
         HashMap,
     },
     ops::Deref,
-    sync::Arc,
+    sync::Arc, 
+    time::Instant,
 };
 
 use tokio::sync::{RwLock, RwLockReadGuard};
@@ -151,6 +152,7 @@ pub struct ProviderConnectionProperties {
     client: FlexibleClient,
     email_scope_supported: bool,
     userinfo_endpoint_supported: bool,
+    time_established: Instant,
     logout_mode: LogoutMode,
 }
 
@@ -179,7 +181,11 @@ impl OpenIDConnectAuthProvider {
     async fn initialize_connection_if_needed(&self) -> KrillResult<()> {
         let mut conn_guard = self.conn.write().await;
 
-        if conn_guard.is_none() {
+        // If we don’t have a connection or it is older than 60 seconds,
+        // get a new one.
+        if conn_guard.as_ref().map(|c| {
+            c.time_established.elapsed().as_secs()
+        }).unwrap_or(60) >= 60 {
             *conn_guard = Some(self.initialize_connection().await?);
         }
 
@@ -194,10 +200,12 @@ impl OpenIDConnectAuthProvider {
         let (email_scope_supported, userinfo_endpoint_supported, logout_mode) =
             self.check_provider_capabilities(&meta)?;
         let client = self.build_client(meta, &logout_mode)?;
+        let time_established = Instant::now();
         let conn = ProviderConnectionProperties {
             client,
             email_scope_supported,
             userinfo_endpoint_supported,
+            time_established,
             logout_mode,
         };
         trace!("OpenID Connect: Provider connection initialized");