Return 409 conflic if build uuid already exists

lib/builder_web.ml

@@ -156,7 +156,19 @@ let routes t =
       Log.warn (fun m -> m "Received bad builder ASN.1");
       Log.debug (fun m -> m "Parse error: %s" e);
       Lwt.return (Response.of_plain_text "Bad request\n" ~status:`Bad_request)
-    | Ok exec ->
+    | Ok ((_, uuid, _, _, _, _, _) as exec) ->
+      Log.info (fun m -> m "Received build %a" pp_exec exec);
+      let* r = Caqti_lwt.Pool.use (Model.build_exists uuid) t.pool in
+      match r with
+      | Error e ->
+        Log.warn (fun m -> m "Error saving build %a: %a" pp_exec exec pp_error e);
+        Lwt.return (Response.of_plain_text "Internal server error\n" ~status:`Internal_server_error)
+      | Ok true ->
+        Log.warn (fun m -> m "Build with same uuid exists: %a" pp_exec exec);
+        Lwt.return (Response.of_plain_text
+                      (Fmt.strf "Build with same uuid exists: %a\n" Uuidm.pp uuid)
+                      ~status:`Conflict)
+      | Ok false ->
         let* r = Caqti_lwt.Pool.use (Model.add_build t.datadir exec) t.pool in
         match r with
         | Ok () ->

lib/model.ml

@@ -45,6 +45,10 @@ let build uuid (module Db : CONN) =
   Db.find_opt Builder_db.Build.get_by_uuid uuid >>=
   not_found
 
+let build_exists uuid (module Db : CONN) =
+  Db.find_opt Builder_db.Build.get_by_uuid uuid >|=
+  Option.is_some
+
 let job job (module Db : CONN) =
   Db.collect_list Builder_db.Build.get_all_meta_by_name job