fix(ds): use integer for tag values

Follow up to https://github.com/emqx/emqx/pull/11906#discussion_r1389115973

apps/emqx_durable_storage/src/emqx_ds_replication_layer.erl

@@ -50,8 +50,8 @@
 %% records over the wire.
 
 %% tags:
--define(stream, stream).
--define(it, it).
+-define(STREAM, 1).
+-define(IT, 2).
 
 %% keys:
 -define(tag, 1).
@@ -68,14 +68,14 @@
 %% account.
 -opaque stream() ::
     #{
-        ?tag := ?stream,
+        ?tag := ?STREAM,
         ?shard := emqx_ds_replication_layer:shard_id(),
         ?enc := emqx_ds_storage_layer:stream()
     }.
 
 -opaque iterator() ::
     #{
-        ?tag := ?it,
+        ?tag := ?IT,
         ?shard := emqx_ds_replication_layer:shard_id(),
         ?enc := emqx_ds_storage_layer:iterator()
     }.
@@ -133,7 +133,7 @@ get_streams(DB, TopicFilter, StartTime) ->
                     RankX = Shard,
                     Rank = {RankX, RankY},
                     {Rank, #{
-                        ?tag => ?stream,
+                        ?tag => ?STREAM,
                         ?shard => Shard,
                         ?enc => Stream
                     }}
@@ -147,18 +147,18 @@ get_streams(DB, TopicFilter, StartTime) ->
 -spec make_iterator(emqx_ds:db(), stream(), emqx_ds:topic_filter(), emqx_ds:time()) ->
     emqx_ds:make_iterator_result(iterator()).
 make_iterator(DB, Stream, TopicFilter, StartTime) ->
-    #{?tag := ?stream, ?shard := Shard, ?enc := StorageStream} = Stream,
+    #{?tag := ?STREAM, ?shard := Shard, ?enc := StorageStream} = Stream,
     Node = node_of_shard(DB, Shard),
     case emqx_ds_proto_v1:make_iterator(Node, DB, Shard, StorageStream, TopicFilter, StartTime) of
         {ok, Iter} ->
-            {ok, #{?tag => ?it, ?shard => Shard, ?enc => Iter}};
+            {ok, #{?tag => ?IT, ?shard => Shard, ?enc => Iter}};
         Err = {error, _} ->
             Err
     end.
 
 -spec next(emqx_ds:db(), iterator(), pos_integer()) -> emqx_ds:next_result(iterator()).
 next(DB, Iter0, BatchSize) ->
-    #{?tag := ?it, ?shard := Shard, ?enc := StorageIter0} = Iter0,
+    #{?tag := ?IT, ?shard := Shard, ?enc := StorageIter0} = Iter0,
     Node = node_of_shard(DB, Shard),
     %% TODO: iterator can contain information that is useful for
     %% reconstructing messages sent over the network. For example,

apps/emqx_durable_storage/src/emqx_ds_storage_bitfield_lts.erl

@@ -42,8 +42,8 @@
 %% records over the wire.
 
 %% tags:
--define(stream, stream).
--define(it, it).
+-define(STREAM, 1).
+-define(IT, 2).
 
 %% keys:
 -define(tag, 1).
@@ -81,13 +81,13 @@
 
 -type stream() ::
     #{
-        ?tag := ?stream,
+        ?tag := ?STREAM,
         ?storage_key := emqx_ds_lts:msg_storage_key()
     }.
 
 -type iterator() ::
     #{
-        ?tag := ?it,
+        ?tag := ?IT,
         ?topic_filter := emqx_ds:topic_filter(),
         ?start_time := emqx_ds:time(),
         ?storage_key := emqx_ds_lts:msg_storage_key(),
@@ -194,7 +194,7 @@ store_batch(_ShardId, S = #s{db = DB, data = Data}, Messages, _Options) ->
 ) -> [stream()].
 get_streams(_Shard, #s{trie = Trie}, TopicFilter, _StartTime) ->
     Indexes = emqx_ds_lts:match_topics(Trie, TopicFilter),
-    [#{?tag => ?stream, ?storage_key => I} || I <- Indexes].
+    [#{?tag => ?STREAM, ?storage_key => I} || I <- Indexes].
 
 -spec make_iterator(
     emqx_ds_storage_layer:shard_id(),
@@ -204,13 +204,13 @@ get_streams(_Shard, #s{trie = Trie}, TopicFilter, _StartTime) ->
     emqx_ds:time()
 ) -> {ok, iterator()}.
 make_iterator(
-    _Shard, _Data, #{?tag := ?stream, ?storage_key := StorageKey}, TopicFilter, StartTime
+    _Shard, _Data, #{?tag := ?STREAM, ?storage_key := StorageKey}, TopicFilter, StartTime
 ) ->
     %% Note: it's a good idea to keep the iterator structure lean,
     %% since it can be stored on a remote node that could update its
     %% code independently from us.
     {ok, #{
-        ?tag => ?it,
+        ?tag => ?IT,
         ?topic_filter => TopicFilter,
         ?start_time => StartTime,
         ?storage_key => StorageKey,
@@ -225,7 +225,7 @@ next(_Shard, Schema = #s{ts_offset = TSOffset}, It, BatchSize) ->
     SafeCutoffTime = (Now bsr TSOffset) bsl TSOffset,
     next_until(Schema, It, SafeCutoffTime, BatchSize).
 
-next_until(_Schema, It = #{?tag := ?it, ?start_time := StartTime}, SafeCutoffTime, _BatchSize) when
+next_until(_Schema, It = #{?tag := ?IT, ?start_time := StartTime}, SafeCutoffTime, _BatchSize) when
     StartTime >= SafeCutoffTime
 ->
     %% We're in the middle of the current epoch, so we can't yet iterate over it.
@@ -235,7 +235,7 @@ next_until(_Schema, It = #{?tag := ?it, ?start_time := StartTime}, SafeCutoffTim
     {ok, It, []};
 next_until(#s{db = DB, data = CF, keymappers = Keymappers}, It, SafeCutoffTime, BatchSize) ->
     #{
-        ?tag := ?it,
+        ?tag := ?IT,
         ?start_time := StartTime,
         ?storage_key := {TopicIndex, Varying}
     } = It,
@@ -286,7 +286,7 @@ next_loop(_ITHandle, _KeyMapper, _Filter, _Cutoff, It, Acc, 0) ->
     {ok, It, lists:reverse(Acc)};
 next_loop(ITHandle, KeyMapper, Filter, Cutoff, It0, Acc0, N0) ->
     inc_counter(),
-    #{?tag := ?it, ?last_seen_key := Key0} = It0,
+    #{?tag := ?IT, ?last_seen_key := Key0} = It0,
     case emqx_ds_bitmask_keymapper:bin_increment(Filter, Key0) of
         overflow ->
             {ok, It0, lists:reverse(Acc0)};
@@ -346,7 +346,7 @@ check_message(
     overflow;
 check_message(
     _Cutoff,
-    #{?tag := ?it, ?start_time := StartTime, ?topic_filter := TopicFilter},
+    #{?tag := ?IT, ?start_time := StartTime, ?topic_filter := TopicFilter},
     #message{timestamp = Timestamp, topic = Topic}
 ) when Timestamp >= StartTime ->
     emqx_topic:match(emqx_topic:words(Topic), TopicFilter);

apps/emqx_durable_storage/src/emqx_ds_storage_layer.erl

@@ -38,8 +38,8 @@
 %% records over the wire.
 
 %% tags:
--define(stream, stream).
--define(it, it).
+-define(STREAM, 1).
+-define(IT, 2).
 
 %% keys:
 -define(tag, 1).
@@ -59,7 +59,7 @@
 %% Note: this might be stored permanently on a remote node.
 -opaque stream() ::
     #{
-        ?tag := ?stream,
+        ?tag := ?STREAM,
         ?generation := gen_id(),
         ?enc := term()
     }.
@@ -67,7 +67,7 @@
 %% Note: this might be stored permanently on a remote node.
 -opaque iterator() ::
     #{
-        ?tag := ?it,
+        ?tag := ?IT,
         ?generation := gen_id(),
         ?enc := term()
     }.
@@ -165,7 +165,7 @@ get_streams(Shard, TopicFilter, StartTime) ->
             Streams = Mod:get_streams(Shard, GenData, TopicFilter, StartTime),
             [
                 {GenId, #{
-                    ?tag => ?stream,
+                    ?tag => ?STREAM,
                     ?generation => GenId,
                     ?enc => Stream
                 }}
@@ -178,13 +178,13 @@ get_streams(Shard, TopicFilter, StartTime) ->
 -spec make_iterator(shard_id(), stream(), emqx_ds:topic_filter(), emqx_ds:time()) ->
     emqx_ds:make_iterator_result(iterator()).
 make_iterator(
-    Shard, #{?tag := ?stream, ?generation := GenId, ?enc := Stream}, TopicFilter, StartTime
+    Shard, #{?tag := ?STREAM, ?generation := GenId, ?enc := Stream}, TopicFilter, StartTime
 ) ->
     #{module := Mod, data := GenData} = generation_get(Shard, GenId),
     case Mod:make_iterator(Shard, GenData, Stream, TopicFilter, StartTime) of
         {ok, Iter} ->
             {ok, #{
-                ?tag => ?it,
+                ?tag => ?IT,
                 ?generation => GenId,
                 ?enc => Iter
             }};
@@ -194,7 +194,7 @@ make_iterator(
 
 -spec next(shard_id(), iterator(), pos_integer()) ->
     emqx_ds:next_result(iterator()).
-next(Shard, Iter = #{?tag := ?it, ?generation := GenId, ?enc := GenIter0}, BatchSize) ->
+next(Shard, Iter = #{?tag := ?IT, ?generation := GenId, ?enc := GenIter0}, BatchSize) ->
     #{module := Mod, data := GenData} = generation_get(Shard, GenId),
     Current = generation_current(Shard),
     case Mod:next(Shard, GenData, GenIter0, BatchSize) of