From 2504b8126b5cb551173bdb722e017f9bbff03db0 Mon Sep 17 00:00:00 2001
From: ieQu1 <99872536+ieQu1@users.noreply.github.com>
Date: Fri, 5 Apr 2024 13:34:32 +0200
Subject: [PATCH] feat(ds): Pass mgmt_ds REST API calls to the application

---
 apps/emqx_management/src/emqx_mgmt_api_ds.erl | 57 ++++++++-----------
 .../test/emqx_mgmt_api_ds_SUITE.erl           |  4 +-
 2 files changed, 26 insertions(+), 35 deletions(-)

diff --git a/apps/emqx_management/src/emqx_mgmt_api_ds.erl b/apps/emqx_management/src/emqx_mgmt_api_ds.erl
index 8e64a7de5..c1a03feb4 100644
--- a/apps/emqx_management/src/emqx_mgmt_api_ds.erl
+++ b/apps/emqx_management/src/emqx_mgmt_api_ds.erl
@@ -349,55 +349,34 @@ db_replica(put, #{bindings := #{ds := DB, site := Site}}) ->
 db_replica(delete, #{bindings := #{ds := DB, site := Site}}) ->
     case leave(DB, Site, rest) of
         ok ->
-            {202, <<"OK">>}
-        %% {error, Description} ->
-        %%     ?BAD_REQUEST(400, Description)
+            {202, <<"OK">>};
+        {error, Description} ->
+            ?BAD_REQUEST(400, Description)
     end.
 
 -spec update_db_sites(emqx_ds:db(), [emqx_ds_replication_layer_meta:site()], rest | cli) ->
     ok | {error, binary()}.
 update_db_sites(DB, Sites, Via) when is_list(Sites) ->
-    UnknownSites = lists:usort(Sites) -- emqx_ds_replication_layer_meta:sites(),
-    case {UnknownSites, Sites} of
-        {[], [_ | _]} ->
-            ?SLOG(warning, #{
-                msg => "durable_storage_rebalance_request", ds => DB, sites => Sites, via => Via
-            }),
-            %% TODO: Do stuff
-            ok;
-        {_, []} ->
-            {error, <<"Empty replica list">>};
-        {UnknownSites, _} ->
-            Message = io_lib:format(
-                "Unknown sites: ~p",
-                [lists:map(fun binary_to_list/1, UnknownSites)]
-            ),
-            {error, iolist_to_binary(Message)}
-    end;
+    ?SLOG(warning, #{
+        msg => "durable_storage_rebalance_request", ds => DB, sites => Sites, via => Via
+    }),
+    meta_result_to_binary(emqx_ds_replication_layer_meta:assign_db_sites(DB, Sites));
 update_db_sites(_, _, _) ->
     {error, <<"Bad type">>}.
 
 -spec join(emqx_ds:db(), emqx_ds_replication_layer_meta:site(), rest | cli) -> ok | {error, _}.
 join(DB, Site, Via) ->
-    case lists:member(Site, emqx_ds_replication_layer_meta:sites()) of
-        true ->
-            ?SLOG(warning, #{
-                msg => "durable_storage_join_request", ds => DB, site => Site, via => Via
-            }),
-            %% TODO: Do stuff
-            ok;
-        false ->
-            Message = io_lib:format("Unknown site: ~s", [Site]),
-            {error, iolist_to_binary(Message)}
-    end.
+    ?SLOG(warning, #{
+        msg => "durable_storage_join_request", ds => DB, site => Site, via => Via
+    }),
+    meta_result_to_binary(emqx_ds_replication_layer_meta:join_db_site(DB, Site)).
 
 -spec leave(emqx_ds:db(), emqx_ds_replication_layer_meta:site(), rest | cli) -> ok | {error, _}.
 leave(DB, Site, Via) ->
-    %% TODO: Do stuff
     ?SLOG(warning, #{
         msg => "durable_storage_leave_request", ds => DB, site => Site, via => Via
     }),
-    ok.
+    meta_result_to_binary(emqx_ds_replication_layer_meta:leave_db_site(DB, Site)).
 
 %%================================================================================
 %% Internal functions
@@ -488,3 +467,15 @@ list_shards(DB) ->
         end
      || Shard <- emqx_ds_replication_layer_meta:shards(DB)
     ].
+
+meta_result_to_binary(ok) ->
+    ok;
+meta_result_to_binary({error, {nonexistent_sites, UnknownSites}}) ->
+    Msg = ["Unknown sites: " | lists:join(", ", UnknownSites)],
+    {error, iolist_to_binary(Msg)};
+meta_result_to_binary({error, {nonexistent_db, DB}}) ->
+    IOList = io_lib:format("Unknown storage: ~p", [DB]),
+    {error, iolist_to_binary(IOList)};
+meta_result_to_binary({error, Err}) ->
+    IOList = io_lib:format("Error: ~p", [Err]),
+    {error, iolist_to_binary(IOList)}.
diff --git a/apps/emqx_management/test/emqx_mgmt_api_ds_SUITE.erl b/apps/emqx_management/test/emqx_mgmt_api_ds_SUITE.erl
index ee0544730..fef9276ca 100644
--- a/apps/emqx_management/test/emqx_mgmt_api_ds_SUITE.erl
+++ b/apps/emqx_management/test/emqx_mgmt_api_ds_SUITE.erl
@@ -144,7 +144,7 @@ t_put_replicas(_) ->
     Path = api_path(["ds", "storages", "emqx_persistent_message", "replicas"]),
     %% Error cases:
     ?assertMatch(
-        {ok, 400, #{<<"message">> := <<"Unknown sites: [\"invalid_site\"]">>}},
+        {ok, 400, #{<<"message">> := <<"Unknown sites: invalid_site">>}},
         parse_error(request_api_with_body(put, Path, [<<"invalid_site">>]))
     ),
     %% Success case:
@@ -170,7 +170,7 @@ t_leave(_) ->
     ThisSite = emqx_ds_replication_layer_meta:this_site(),
     Path = api_path(["ds", "storages", "emqx_persistent_message", "replicas", ThisSite]),
     ?assertMatch(
-        {ok, "OK"},
+        {error, {_, 400, _}},
         request_api(delete, Path)
     ).