From 40d7bb04b470ef036429e3592407bfa14130fd1f Mon Sep 17 00:00:00 2001
From: Andrey Antukh <niwi@niwi.nz>
Date: Wed, 16 Oct 2024 17:35:47 +0200
Subject: [PATCH] :sparkles: Reuse permission from rpc/cond middleware for
 get-file rpc method

---
 backend/src/app/rpc/commands/files.clj                | 10 +++++++++-
 backend/src/app/rpc/cond.clj                          | 11 ++++++++---
 .../test/backend_tests/rpc_cond_middleware_test.clj   |  1 -
 3 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/backend/src/app/rpc/commands/files.clj b/backend/src/app/rpc/commands/files.clj
index c8aa562045..1ca28fd64d 100644
--- a/backend/src/app/rpc/commands/files.clj
+++ b/backend/src/app/rpc/commands/files.clj
@@ -295,8 +295,16 @@
    ::sm/result schema:file-with-permissions}
   [cfg {:keys [::rpc/profile-id id project-id] :as params}]
   (db/tx-run! cfg (fn [{:keys [::db/conn] :as cfg}]
-                    (let [perms (get-permissions conn profile-id id)]
+                    ;; The COND middleware makes initial request for a file and
+                    ;; permissions when the incoming request comes with an
+                    ;; ETAG. When ETAG does not matches, the request is resolved
+                    ;; and this code is executed, in this case the permissions
+                    ;; will be already prefetched and we just reuse them instead
+                    ;; of making an additional database queries.
+                    (let [perms (or (:permissions (::cond/object params))
+                                    (get-permissions conn profile-id id))]
                       (check-read-permissions! perms)
+
                       (let [team (teams/get-team conn
                                                  :profile-id profile-id
                                                  :project-id project-id
diff --git a/backend/src/app/rpc/cond.clj b/backend/src/app/rpc/cond.clj
index bf724d13f5..2c79d8f664 100644
--- a/backend/src/app/rpc/cond.clj
+++ b/backend/src/app/rpc/cond.clj
@@ -54,11 +54,16 @@
       (l/trc :hint "instrumenting method" :service (::sv/name mdata))
       (fn [cfg {:keys [::key] :as params}]
         (if *enabled*
-          (let [key' (when (or reuse-key? key)
-                       (some->> (get-object cfg params) (key-fn params) (fmt-key)))]
+          (let [object (when (some? key)
+                         (get-object cfg params))
+                key'   (when (some? object)
+                         (->> object (key-fn params) (fmt-key)))]
             (if (and (some? key) (= key key'))
               (fn [_] {::rres/status 304})
-              (let [result (f cfg params)
+              (let [params (if (some? object)
+                             (assoc params ::object object)
+                             params)
+                    result (f cfg params)
                     etag   (or (and reuse-key? key')
                                (some->> result meta ::key fmt-key)
                                (some->> result (key-fn params) fmt-key))]
diff --git a/backend/test/backend_tests/rpc_cond_middleware_test.clj b/backend/test/backend_tests/rpc_cond_middleware_test.clj
index e74a9c5497..e737fc5f5e 100644
--- a/backend/test/backend_tests/rpc_cond_middleware_test.clj
+++ b/backend/test/backend_tests/rpc_cond_middleware_test.clj
@@ -39,7 +39,6 @@
         (t/is (nil? error))
         (t/is (map? result))
         (t/is (contains? (meta result) :app.http/headers))
-        (t/is (contains? (meta result) :app.rpc.cond/key))
 
         (let [etag (-> result meta :app.http/headers (get "etag"))
               {:keys [error result]} (th/command! (assoc params ::cond/key etag))]