Use prepared queries for mod_last

esl · Feb 5, 2021 · abc5a1a · abc5a1a
1 parent 7fd536c
commit abc5a1a
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Showing 2 changed files with 48 additions and 62 deletions.
diff --git a/src/mod_last_rdbms.erl b/src/mod_last_rdbms.erl
@@ -25,52 +25,66 @@
          remove_user/2]).
 
 -spec init(jid:server(), list()) -> ok.
-init(_Host, _Opts) ->
+init(Host, _Opts) ->
+    prepare_queries(Host),
     ok.
 
+%% Prepared query functions
+prepare_queries(Host) ->
+    mongoose_rdbms:prepare(last_select, last, [username],
+                           <<"SELECT seconds, state FROM last WHERE username=?">>),
+    mongoose_rdbms:prepare(last_count_active, last, [seconds],
+                           <<"SELECT COUNT(*) FROM last WHERE seconds > ?">>),
+    mongoose_rdbms:prepare(last_delete, last, [username],
+                           <<"delete from last where username=?">>),
+    rdbms_queries:prepare_upsert(Host, last_upsert, last,
+                                 [<<"username">>, <<"seconds">>, <<"state">>],
+                                 [<<"seconds">>, <<"state">>],
+                                 [<<"username">>]).
+
+execute_get_last(LServer, LUser) ->
+    mongoose_rdbms:execute_successfully(LServer, last_select, [LUser]).
+
+execute_count_active_users(LServer, Seconds) ->
+    mongoose_rdbms:execute_successfully(LServer, last_count_active, [Seconds]).
+
+execute_remove_user(LServer, LUser) ->
+    mongoose_rdbms:execute_successfully(LServer, last_delete, [LUser]).
+
+execute_upsert_last(Host, LUser, Seconds, State) ->
+    InsertParams = [LUser, Seconds, State],
+    UpdateParams = [Seconds, State],
+    UniqueKeyValues = [LUser],
+    rdbms_queries:execute_upsert(Host, last_upsert, InsertParams, UpdateParams, UniqueKeyValues).
+
+%% API functions
 -spec get_last(jid:luser(), jid:lserver()) ->
-    {ok, non_neg_integer(), binary()} | {error, term()} | not_found.
+    {ok, non_neg_integer(), binary()} | not_found.
 get_last(LUser, LServer) ->
-    Username = mongoose_rdbms:escape_string(LUser),
-    case catch rdbms_queries:get_last(LServer, Username) of
-        {selected, []} ->
-            not_found;
-        {selected, [{STimeStamp, Status}]} ->
-            case catch mongoose_rdbms:result_to_integer(STimeStamp) of
-                TimeStamp when is_integer(TimeStamp) ->
-                    {ok, TimeStamp, Status};
-                Reason ->
-                    {error, {invalid_timestamp, Reason}}
-            end;
-        Reason -> {error, {invalid_result, Reason}}
-    end.
+    Result = execute_get_last(LServer, LUser),
+    decode_last_result(Result).
 
 -spec count_active_users(jid:lserver(), non_neg_integer()) -> non_neg_integer().
-count_active_users(LServer, TimeStamp) ->
-    TimeStampBin = integer_to_binary(TimeStamp),
-    WhereClause = <<"where seconds > ", TimeStampBin/binary >>,
-    case rdbms_queries:count_records_where(LServer, <<"last">>, WhereClause) of
-        {selected, [{Count}]} ->
-            mongoose_rdbms:result_to_integer(Count);
-        _ ->
-            0
-    end.
+count_active_users(LServer, Seconds) ->
+    Result = execute_count_active_users(LServer, Seconds),
+    mongoose_rdbms:selected_to_integer(Result).
 
 -spec set_last_info(jid:luser(), jid:lserver(),
-                    non_neg_integer(), binary()) ->
-    ok | {error, term()}.
-set_last_info(LUser, LServer, TimeStamp, Status) ->
-    Username = mongoose_rdbms:escape_string(LUser),
-    Seconds = mongoose_rdbms:escape_integer(TimeStamp),
-    State = mongoose_rdbms:escape_string(Status),
-    wrap_rdbms_result(rdbms_queries:set_last_t(LServer, Username, Seconds, State)).
+                    non_neg_integer(), binary()) -> ok | {error, term()}.
+set_last_info(LUser, LServer, Seconds, State) ->
+    wrap_rdbms_result(execute_upsert_last(LServer, LUser, Seconds, State)).
 
 -spec remove_user(jid:luser(), jid:lserver()) -> ok | {error, term()}.
 remove_user(LUser, LServer) ->
-    Username = mongoose_rdbms:escape_string(LUser),
-    wrap_rdbms_result(rdbms_queries:del_last(LServer, Username)).
+    wrap_rdbms_result(execute_remove_user(LServer, LUser)).
+
+%% Helper functions
+decode_last_result({selected, []}) ->
+    not_found;
+decode_last_result({selected, [{DbSeconds, State}]}) ->
+    Seconds = mongoose_rdbms:result_to_integer(DbSeconds),
+    {ok, Seconds, State}.
 
 -spec wrap_rdbms_result({error, term()} | any()) -> ok | {error, term()}.
 wrap_rdbms_result({error, _} = Error) -> Error;
 wrap_rdbms_result(_) -> ok.
-
diff --git a/src/rdbms/rdbms_queries.erl b/src/rdbms/rdbms_queries.erl
@@ -35,10 +35,6 @@
          limit_offset_sql/0,
          limit_offset_args/2,
          sql_transaction/2,
-         get_last/2,
-         select_last/3,
-         set_last_t/4,
-         del_last/2,
          get_password/2,
          set_password_t/3,
          add_user/3,
@@ -247,30 +243,6 @@ begin_trans(mssql) ->
 begin_trans(_) ->
     [<<"BEGIN;">>].
 
-
-get_last(LServer, Username) ->
-    mongoose_rdbms:sql_query(
-      LServer,
-      [<<"select seconds, state from last "
-         "where username=">>, mongoose_rdbms:use_escaped_string(Username)]).
-
-select_last(LServer, TStamp, Comparator) ->
-    mongoose_rdbms:sql_query(
-        LServer,
-        [<<"select username, seconds, state from last "
-           "where seconds ">>, Comparator, " ",
-         mongoose_rdbms:use_escaped_integer(mongoose_rdbms:escape_integer(TStamp)), ";"]).
-
-set_last_t(LServer, Username, Seconds, State) ->
-    update(LServer, "last", ["username", "seconds", "state"],
-           [Username, Seconds, State],
-           [<<"username=">>, mongoose_rdbms:use_escaped_string(Username)]).
-
-del_last(LServer, Username) ->
-    mongoose_rdbms:sql_query(
-      LServer,
-      [<<"delete from last where username=">>, mongoose_rdbms:use_escaped_string(Username)]).
-
 get_password(LServer, Username) ->
     mongoose_rdbms:sql_query(
       LServer,