⚡ Cache OIDC provider records to skip per-login discovery (#9295)

Co-authored-by: Andrey Antukh <niwi@niwi.nz>

backend/src/app/auth/oidc.clj

@@ -27,6 +27,7 @@
    [app.rpc.commands.profile :as profile]
    [app.setup :as-alias setup]
    [app.tokens :as tokens]
+   [app.util.cache :as cache]
    [app.util.inet :as inet]
    [app.util.json :as json]
    [buddy.sign.jwk :as jwk]
@@ -694,15 +695,24 @@
     (db/pgarray? roles)
     (assoc :roles (db/decode-pgarray roles #{}))))
 
-;; TODO: add cache layer for avoid build an discover each time
+;; A short TTL avoids paying the OIDC discovery + JWKS fetch on every
+;; login; Caffeine will not store the entry when the load fn throws,
+;; so a transient failure at the provider's discovery endpoint does
+;; not poison the cache.
+(defonce ^:private provider-cache
+  (cache/create :expire "10m" :max-size 64))
+
+(defn- load-provider
+  [cfg id]
+  (when-let [params (some->> (db/get* cfg :sso-provider {:id id :is-enabled true})
+                             (decode-row))]
+    (case (:type params)
+      "oidc" (prepare-oidc-provider cfg params))))
 
 (defn get-provider
   [cfg id]
   (try
-    (when-let [params (some->> (db/get* cfg :sso-provider {:id id :is-enabled true})
-                               (decode-row))]
-      (case (:type params)
-        "oidc" (prepare-oidc-provider cfg params)))
+    (cache/get provider-cache id (partial load-provider cfg))
     (catch Throwable cause
       (l/err :hint "unable to configure custom SSO provider"
              :provider (str id)

backend/src/app/util/cache.clj

@@ -12,7 +12,6 @@
    [app.common.time :as ct]
    [promesa.exec :as px])
   (:import
-   com.github.benmanes.caffeine.cache.AsyncCache
    com.github.benmanes.caffeine.cache.Cache
    com.github.benmanes.caffeine.cache.Caffeine
    com.github.benmanes.caffeine.cache.RemovalListener
@@ -47,15 +46,18 @@
      :miss-rate  (.missRate stats)}))
 
 (defn create
-  [& {:keys [executor on-remove max-size keepalive]}]
+  "Build an in-memory cache. Loads run synchronously on the calling
+  thread, so when a load fn throws or returns nil the entry is not
+  stored — concurrent loads for the same key still deduplicate."
+  [& {:keys [executor on-remove max-size keepalive expire]}]
   (let [cache (as-> (Caffeine/newBuilder) builder
                 (if (fn? on-remove) (.removalListener builder (create-listener on-remove)) builder)
                 (if executor  (.executor builder ^Executor (px/resolve-executor executor)) builder)
                 (if keepalive (.expireAfterAccess builder ^Duration (ct/duration keepalive)) builder)
+                (if expire    (.expireAfterWrite  builder ^Duration (ct/duration expire)) builder)
                 (if (int? max-size) (.maximumSize builder (long max-size)) builder)
                 (.recordStats builder)
-                (.buildAsync builder))
-        cache (.synchronous ^AsyncCache cache)]
+                (.build builder))]
     (reify
       ICache
       (get [_ k]
@@ -69,7 +71,7 @@
       (invalidate! [_]
         (.invalidateAll ^Cache cache))
       (invalidate! [_ k]
-        (.invalidateAll ^Cache cache ^Object k))
+        (.invalidate ^Cache cache ^Object k))
 
       ICacheStats
       (stats [_]