test(ds): Use streams to fill the storage

This commit is contained in:
ieQu1 2024-05-09 01:20:15 +02:00
parent a0a3977043
commit 63e51fca66
No known key found for this signature in database
GPG Key ID: 488654DF3FED6FDE
2 changed files with 186 additions and 219 deletions

View File

@ -30,7 +30,7 @@
). ).
-define(diff_opts, #{ -define(diff_opts, #{
context => 20, window => 1000, max_failures => 1000, compare_fun => fun message_eq/2 context => 20, window => 1000, compare_fun => fun message_eq/2
}). }).
opts() -> opts() ->
@ -76,64 +76,59 @@ t_replication_transfers_snapshots('end', Config) ->
ok = emqx_cth_cluster:stop(?config(nodes, Config)). ok = emqx_cth_cluster:stop(?config(nodes, Config)).
t_replication_transfers_snapshots(Config) -> t_replication_transfers_snapshots(Config) ->
NMsgs = 4000, NMsgs = 400,
NClients = 5,
{Stream, TopicStreams} = interleaved_topic_messages(?FUNCTION_NAME, NClients, NMsgs),
Nodes = [Node, NodeOffline | _] = ?config(nodes, Config), Nodes = [Node, NodeOffline | _] = ?config(nodes, Config),
_Specs = [_, SpecOffline | _] = ?config(specs, Config), _Specs = [_, SpecOffline | _] = ?config(specs, Config),
?check_trace(
begin
%% Initialize DB on all nodes and wait for it to be online.
Opts = opts(#{n_shards => 1, n_sites => 3}),
?assertEqual(
[{ok, ok} || _ <- Nodes],
erpc:multicall(Nodes, emqx_ds, open_db, [?DB, Opts])
),
?retry(
500,
10,
?assertMatch([[_], [_], [_]], [shards_online(N, ?DB) || N <- Nodes])
),
%% Initialize DB on all nodes and wait for it to be online. %% Stop the DB on the "offline" node.
Opts = opts(#{n_shards => 1, n_sites => 3}), ok = emqx_cth_cluster:stop_node(NodeOffline),
?assertEqual(
[{ok, ok} || _ <- Nodes],
erpc:multicall(Nodes, emqx_ds, open_db, [?DB, Opts])
),
?retry(
500,
10,
?assertMatch([[_], [_], [_]], [shards_online(N, ?DB) || N <- Nodes])
),
%% Stop the DB on the "offline" node. %% Fill the storage with messages and few additional generations.
ok = emqx_cth_cluster:stop_node(NodeOffline), apply_stream(?DB, Nodes -- [NodeOffline], Stream),
%% Fill the storage with messages and few additional generations. %% Restart the node.
Messages = fill_storage(Node, ?DB, NMsgs, #{p_addgen => 0.01}), [NodeOffline] = emqx_cth_cluster:restart(SpecOffline),
{ok, SRef} = snabbkaffe:subscribe(
?match_event(#{
?snk_kind := dsrepl_snapshot_accepted,
?snk_meta := #{node := NodeOffline}
})
),
?assertEqual(
ok,
erpc:call(NodeOffline, emqx_ds, open_db, [?DB, opts()])
),
%% Restart the node. %% Trigger storage operation and wait the replica to be restored.
[NodeOffline] = emqx_cth_cluster:restart(SpecOffline), _ = add_generation(Node, ?DB),
{ok, SRef} = snabbkaffe:subscribe( ?assertMatch(
?match_event(#{ {ok, _},
?snk_kind := dsrepl_snapshot_accepted, snabbkaffe:receive_events(SRef)
?snk_meta := #{node := NodeOffline} ),
})
),
?assertEqual(
ok,
erpc:call(NodeOffline, emqx_ds, open_db, [?DB, opts()])
),
%% Trigger storage operation and wait the replica to be restored. %% Wait until any pending replication activities are finished (e.g. Raft log entries).
_ = add_generation(Node, ?DB), ok = timer:sleep(3_000),
?assertMatch(
{ok, _},
snabbkaffe:receive_events(SRef)
),
%% Wait until any pending replication activities are finished (e.g. Raft log entries). %% Check that the DB has been restored:
ok = timer:sleep(3_000), verify_stream_effects(?FUNCTION_NAME, Nodes, TopicStreams)
end,
%% Check that the DB has been restored. []
Shard = hd(shards(NodeOffline, ?DB)),
MessagesOffline = lists:keysort(
#message.timestamp,
consume_shard(NodeOffline, ?DB, Shard, ['#'], 0)
),
?assertEqual(
sample(40, Messages),
sample(40, MessagesOffline)
),
?assertEqual(
Messages,
MessagesOffline
). ).
t_rebalance(init, Config) -> t_rebalance(init, Config) ->
@ -159,50 +154,13 @@ t_rebalance('end', Config) ->
t_rebalance(Config) -> t_rebalance(Config) ->
NMsgs = 50, NMsgs = 50,
NClients = 5, NClients = 5,
%% List of fake client IDs: {Stream0, TopicStreams} = interleaved_topic_messages(?FUNCTION_NAME, NClients, NMsgs),
Clients = [integer_to_binary(I) || I <- lists:seq(1, NClients)], Nodes = [N1, N2 | _] = ?config(nodes, Config),
%% List of streams that generate messages for each "client" in its own topic:
TopicStreams = [
{ClientId, emqx_utils_stream:limit_length(NMsgs, topic_messages(?FUNCTION_NAME, ClientId))}
|| ClientId <- Clients
],
%% Interleaved list of events:
Stream0 = emqx_utils_stream:interleave(
[{2, Stream} || {_ClientId, Stream} <- TopicStreams], true
),
Stream = emqx_utils_stream:interleave(
[
{50, Stream0},
emqx_utils_stream:const(add_generation)
],
false
),
Nodes = [N1, N2, N3, N4] = ?config(nodes, Config),
?check_trace( ?check_trace(
#{timetrap => 30_000}, #{timetrap => 30_000},
begin begin
%% 0. Inject schedulings to make sure the messages are
%% written to the storage before, during, and after
%% rebalance:
?force_ordering(
#{?snk_kind := test_push_message, n := 10},
#{?snk_kind := test_start_rebalance}
),
?force_ordering(
#{?snk_kind := test_start_rebalance1},
#{?snk_kind := test_push_message, n := 20}
),
?force_ordering(
#{?snk_kind := test_push_message, n := 30},
#{?snk_kind := test_start_rebalance2}
),
?force_ordering(
#{?snk_kind := test_end_rebalance},
#{?snk_kind := test_push_message, n := 40}
),
%% 1. Initialize DB on the first node. %% 1. Initialize DB on the first node.
Opts = opts(#{n_shards => 16, n_sites => 1, replication_factor => 3}), Opts = opts(#{n_shards => 16, n_sites => 1, replication_factor => 3}),
?assertEqual(ok, ?ON(N1, emqx_ds:open_db(?DB, Opts))), ?assertEqual(ok, ?ON(N1, emqx_ds:open_db(?DB, Opts))),
?assertMatch(Shards when length(Shards) == 16, shards_online(N1, ?DB)), ?assertMatch(Shards when length(Shards) == 16, shards_online(N1, ?DB)),
@ -215,6 +173,22 @@ t_rebalance(Config) ->
Sites = [S1, S2 | _] = [ds_repl_meta(N, this_site) || N <- Nodes], Sites = [S1, S2 | _] = [ds_repl_meta(N, this_site) || N <- Nodes],
ct:pal("Sites: ~p~n", [Sites]), ct:pal("Sites: ~p~n", [Sites]),
Sequence = [
%% Join the second site to the DB replication sites:
{N1, join_db_site, S2},
%% Should be a no-op:
{N2, join_db_site, S2},
%% Now join the rest of the sites:
{N2, assign_db_sites, Sites}
],
Stream = emqx_utils_stream:interleave(
[
{50, Stream0},
emqx_utils_stream:list(Sequence)
],
true
),
%% 1.2 Verify that all nodes have the same view of metadata storage: %% 1.2 Verify that all nodes have the same view of metadata storage:
[ [
?defer_assert( ?defer_assert(
@ -231,31 +205,9 @@ t_rebalance(Config) ->
], ],
%% 2. Start filling the storage: %% 2. Start filling the storage:
spawn_link( apply_stream(?DB, Nodes, Stream),
fun() -> timer:sleep(5000),
NodeStream = emqx_utils_stream:repeat(emqx_utils_stream:list(Nodes)), verify_stream_effects(?FUNCTION_NAME, Nodes, TopicStreams),
apply_stream(?DB, NodeStream, Stream, 0)
end
),
%% 3. Start rebalance in the meanwhile:
?tp(test_start_rebalance1, #{}),
%% 3.1 Join the second site to the DB replication sites.
?assertEqual(ok, ?ON(N1, emqx_ds_replication_layer_meta:join_db_site(?DB, S2))),
%% Should be no-op.
?assertEqual(ok, ?ON(N2, emqx_ds_replication_layer_meta:join_db_site(?DB, S2))),
ct:pal("Transitions (~p -> ~p): ~p~n", [[S1], [S1, S2], transitions(N1, ?DB)]),
?retry(1000, 10, ?assertEqual([], transitions(N1, ?DB))),
?tp(test_start_rebalance2, #{}),
%% Now join the rest of the sites.
?assertEqual(ok, ds_repl_meta(N2, assign_db_sites, [?DB, Sites])),
ct:pal("Transitions (~p -> ~p): ~p~n", [[S1, S2], Sites, transitions(N1, ?DB)]),
?retry(1000, 10, ?assertEqual([], transitions(N2, ?DB))),
?tp(test_end_rebalance, #{}),
[ [
?defer_assert( ?defer_assert(
?assertEqual( ?assertEqual(
@ -279,17 +231,12 @@ t_rebalance(Config) ->
ShardServers ShardServers
), ),
%% Verify that the messages are preserved after the rebalance:
?block_until(#{?snk_kind := all_done}),
timer:sleep(5000),
verify_stream_effects(?FUNCTION_NAME, Nodes, TopicStreams),
%% Scale down the cluster by removing the first node. %% Scale down the cluster by removing the first node.
?assertEqual(ok, ds_repl_meta(N1, leave_db_site, [?DB, S1])), ?assertEqual(ok, ds_repl_meta(N1, leave_db_site, [?DB, S1])),
ct:pal("Transitions (~p -> ~p): ~p~n", [Sites, tl(Sites), transitions(N1, ?DB)]), ct:pal("Transitions (~p -> ~p): ~p~n", [Sites, tl(Sites), transitions(N1, ?DB)]),
?retry(1000, 10, ?assertEqual([], transitions(N2, ?DB))), ?retry(1000, 10, ?assertEqual([], transitions(N2, ?DB))),
%% Verify that each node is now responsible for each shard. %% Verify that at the end each node is now responsible for each shard.
?defer_assert( ?defer_assert(
?assertEqual( ?assertEqual(
[0, 16, 16, 16], [0, 16, 16, 16],
@ -387,81 +334,77 @@ t_rebalance_chaotic_converges(Config) ->
NMsgs = 500, NMsgs = 500,
Nodes = [N1, N2, N3] = ?config(nodes, Config), Nodes = [N1, N2, N3] = ?config(nodes, Config),
%% Initialize DB on first two nodes. NClients = 5,
Opts = opts(#{n_shards => 16, n_sites => 2, replication_factor => 3}), {Stream0, TopicStreams} = interleaved_topic_messages(?FUNCTION_NAME, NClients, NMsgs),
?assertEqual(
[{ok, ok}, {ok, ok}],
erpc:multicall([N1, N2], emqx_ds, open_db, [?DB, Opts])
),
%% Open DB on the last node. ?check_trace(
?assertEqual( #{},
ok, begin
erpc:call(N3, emqx_ds, open_db, [?DB, Opts]) %% Initialize DB on first two nodes.
), Opts = opts(#{n_shards => 16, n_sites => 2, replication_factor => 3}),
%% Find out which sites there are. ?assertEqual(
Sites = [S1, S2, S3] = [ds_repl_meta(N, this_site) || N <- Nodes], [{ok, ok}, {ok, ok}],
ct:pal("Sites: ~p~n", [Sites]), erpc:multicall([N1, N2], emqx_ds, open_db, [?DB, Opts])
),
%% Initially, the DB is assigned to [S1, S2]. %% Open DB on the last node.
?retry(500, 10, ?assertEqual([16, 16], [n_shards_online(N, ?DB) || N <- [N1, N2]])), ?assertEqual(
?assertEqual( ok,
lists:sort([S1, S2]), erpc:call(N3, emqx_ds, open_db, [?DB, Opts])
ds_repl_meta(N1, db_sites, [?DB]) ),
),
%% Fill the storage with messages and few additional generations. %% Find out which sites there are.
Messages0 = lists:append([ Sites = [S1, S2, S3] = [ds_repl_meta(N, this_site) || N <- Nodes],
fill_storage(N1, ?DB, NMsgs, #{client_id => <<"C1">>}), ct:pal("Sites: ~p~n", [Sites]),
fill_storage(N2, ?DB, NMsgs, #{client_id => <<"C2">>}),
fill_storage(N3, ?DB, NMsgs, #{client_id => <<"C3">>})
]),
%% Construct a chaotic transition sequence that changes assignment to [S2, S3]. Sequence = [
Sequence = [ {N1, join_db_site, S3},
{N1, join_db_site, S3}, {N2, leave_db_site, S2},
{N2, leave_db_site, S2}, {N3, leave_db_site, S1},
{N3, leave_db_site, S1}, {N1, join_db_site, S2},
{N1, join_db_site, S2}, {N2, join_db_site, S1},
{N2, join_db_site, S1}, {N3, leave_db_site, S3},
{N3, leave_db_site, S3}, {N1, leave_db_site, S1},
{N1, leave_db_site, S1}, {N2, join_db_site, S3}
{N2, join_db_site, S3} ],
],
%% Apply the sequence while also filling the storage with messages. %% Interleaved list of events:
TransitionMessages = lists:map( Stream = emqx_utils_stream:interleave(
fun({N, Operation, Site}) -> [
%% Apply the transition. {50, Stream0},
?assertEqual(ok, ds_repl_meta(N, Operation, [?DB, Site])), emqx_utils_stream:list(Sequence)
%% Give some time for at least one transition to complete. ],
Transitions = transitions(N, ?DB), true
ct:pal("Transitions after ~p: ~p", [Operation, Transitions]), ),
?retry(200, 10, ?assertNotEqual(Transitions, transitions(N, ?DB))),
%% Fill the storage with messages. ?retry(500, 10, ?assertEqual([16, 16], [n_shards_online(N, ?DB) || N <- [N1, N2]])),
CID = integer_to_binary(erlang:system_time()), ?assertEqual(
fill_storage(N, ?DB, NMsgs, #{client_id => CID}) lists:sort([S1, S2]),
ds_repl_meta(N1, db_sites, [?DB]),
"Initially, the DB is assigned to [S1, S2]"
),
apply_stream(?DB, Nodes, Stream),
%% Wait for the last transition to complete.
?retry(500, 20, ?assertEqual([], transitions(N1, ?DB))),
?defer_assert(
?assertEqual(
lists:sort([S2, S3]),
ds_repl_meta(N1, db_sites, [?DB])
)
),
%% Wait until the LTS timestamp is updated:
timer:sleep(5000),
%% Check that all messages are still there.
verify_stream_effects(?FUNCTION_NAME, Nodes, TopicStreams)
end, end,
Sequence []
), ).
%% Wait for the last transition to complete.
?retry(500, 20, ?assertEqual([], transitions(N1, ?DB))),
?assertEqual(
lists:sort([S2, S3]),
ds_repl_meta(N1, db_sites, [?DB])
),
%% Wait until the LTS timestamp is updated
timer:sleep(5000),
%% Check that all messages are still there.
Messages = lists:append(TransitionMessages) ++ Messages0,
MessagesDB = lists:sort(fun compare_message/2, consume(N1, ?DB, ['#'], 0)),
?assertEqual(sample(20, Messages), sample(20, MessagesDB)),
?assertEqual(Messages, MessagesDB).
t_rebalance_offline_restarts(init, Config) -> t_rebalance_offline_restarts(init, Config) ->
Apps = [appspec(emqx_durable_storage)], Apps = [appspec(emqx_durable_storage)],
@ -535,7 +478,15 @@ ds_repl_meta(Node, Fun) ->
ds_repl_meta(Node, Fun, []). ds_repl_meta(Node, Fun, []).
ds_repl_meta(Node, Fun, Args) -> ds_repl_meta(Node, Fun, Args) ->
erpc:call(Node, emqx_ds_replication_layer_meta, Fun, Args). try
erpc:call(Node, emqx_ds_replication_layer_meta, Fun, Args)
catch
EC:Err:Stack ->
ct:pal("emqx_ds_replication_layer_meta:~p(~p) @~p failed:~n~p:~p~nStack: ~p", [
Fun, Args, Node, EC, Err, Stack
]),
error(meta_op_failed)
end.
ds_repl_shard(Node, Fun, Args) -> ds_repl_shard(Node, Fun, Args) ->
erpc:call(Node, emqx_ds_replication_layer_shard, Fun, Args). erpc:call(Node, emqx_ds_replication_layer_shard, Fun, Args).
@ -553,27 +504,6 @@ shards_online(Node, DB) ->
n_shards_online(Node, DB) -> n_shards_online(Node, DB) ->
length(shards_online(Node, DB)). length(shards_online(Node, DB)).
fill_storage(Node, DB, NMsgs, Opts) ->
fill_storage(Node, DB, NMsgs, 0, Opts).
fill_storage(Node, DB, NMsgs, I, Opts) when I < NMsgs ->
PAddGen = maps:get(p_addgen, Opts, 0.001),
R1 = push_message(Node, DB, I, Opts),
%probably(PAddGen, fun() -> add_generation(Node, DB) end),
R2 = [],
R1 ++ R2 ++ fill_storage(Node, DB, NMsgs, I + 1, Opts);
fill_storage(_Node, _DB, NMsgs, NMsgs, _Opts) ->
[].
push_message(Node, DB, I, Opts) ->
Topic = emqx_topic:join([<<"topic">>, <<"foo">>, integer_to_binary(I)]),
%% {Bytes, _} = rand:bytes_s(5, rand:seed_s(default, I)),
Bytes = integer_to_binary(I),
ClientId = maps:get(client_id, Opts, <<?MODULE_STRING>>),
Message = message(ClientId, Topic, Bytes, I * 100),
ok = erpc:call(Node, emqx_ds, store_batch, [DB, [Message], #{sync => true}]),
[Message].
add_generation(Node, DB) -> add_generation(Node, DB) ->
ok = erpc:call(Node, emqx_ds, add_generation, [DB]), ok = erpc:call(Node, emqx_ds, add_generation, [DB]),
[]. [].
@ -674,7 +604,7 @@ do_ds_topic_generation_stream(Node, Shard, It0) ->
end end
) )
of of
{ok, It, []} -> {ok, _It, []} ->
[]; [];
{ok, end_of_stream} -> {ok, end_of_stream} ->
[]; [];
@ -685,11 +615,19 @@ do_ds_topic_generation_stream(Node, Shard, It0) ->
%% Payload generation: %% Payload generation:
apply_stream(DB, Nodes, Stream) ->
apply_stream(
DB,
emqx_utils_stream:repeat(emqx_utils_stream:list(Nodes)),
Stream,
0
).
apply_stream(DB, NodeStream0, Stream0, N) -> apply_stream(DB, NodeStream0, Stream0, N) ->
case emqx_utils_stream:next(Stream0) of case emqx_utils_stream:next(Stream0) of
[] -> [] ->
?tp(all_done, #{}); ?tp(all_done, #{});
[Msg = #message{from = From} | Stream] -> [Msg = #message{} | Stream] ->
[Node | NodeStream] = emqx_utils_stream:next(NodeStream0), [Node | NodeStream] = emqx_utils_stream:next(NodeStream0),
?tp( ?tp(
test_push_message, test_push_message,
@ -701,12 +639,40 @@ apply_stream(DB, NodeStream0, Stream0, N) ->
?ON(Node, emqx_ds:store_batch(DB, [Msg], #{sync => true})), ?ON(Node, emqx_ds:store_batch(DB, [Msg], #{sync => true})),
apply_stream(DB, NodeStream, Stream, N + 1); apply_stream(DB, NodeStream, Stream, N + 1);
[add_generation | Stream] -> [add_generation | Stream] ->
[Node | NodeStream] = emqx_utils_stream:next(NodeStream0), %% FIXME:
[_Node | NodeStream] = emqx_utils_stream:next(NodeStream0),
%% add_generation(Node, DB), %% add_generation(Node, DB),
apply_stream(DB, NodeStream, Stream, N) apply_stream(DB, NodeStream, Stream, N);
[{Node, Operation, Arg} | Stream] when
Operation =:= join_db_site; Operation =:= leave_db_site; Operation =:= assign_db_sites
->
?tp(notice, test_apply_operation, #{node => Node, operation => Operation, arg => Arg}),
%% Apply the transition.
?assertEqual(ok, ds_repl_meta(Node, Operation, [DB, Arg])),
%% Give some time for at least one transition to complete.
Transitions = transitions(Node, ?DB),
ct:pal("Transitions after ~p: ~p", [Operation, Transitions]),
?retry(200, 10, ?assertNotEqual(Transitions, transitions(Node, DB))),
apply_stream(DB, NodeStream0, Stream, N);
[Fun | Stream] when is_function(Fun) ->
Fun(),
apply_stream(DB, NodeStream0, Stream, N)
end. end.
%% @doc Create an infinite list of messages from a given client: %% @doc Create an infinite list of messages from a given client:
interleaved_topic_messages(TestCase, NClients, NMsgs) ->
%% List of fake client IDs:
Clients = [integer_to_binary(I) || I <- lists:seq(1, NClients)],
TopicStreams = [
{ClientId, emqx_utils_stream:limit_length(NMsgs, topic_messages(TestCase, ClientId))}
|| ClientId <- Clients
],
%% Interleaved stream of messages:
Stream = emqx_utils_stream:interleave(
[{2, Stream} || {_ClientId, Stream} <- TopicStreams], true
),
{Stream, TopicStreams}.
topic_messages(TestCase, ClientId) -> topic_messages(TestCase, ClientId) ->
topic_messages(TestCase, ClientId, 0). topic_messages(TestCase, ClientId, 0).
@ -726,7 +692,7 @@ client_topic(TestCase, ClientId) when is_atom(TestCase) ->
client_topic(TestCase, ClientId) when is_binary(TestCase) -> client_topic(TestCase, ClientId) when is_binary(TestCase) ->
<<TestCase/binary, "/", ClientId/binary>>. <<TestCase/binary, "/", ClientId/binary>>.
message_eq(Msg1, {Key, Msg2}) -> message_eq(Msg1, {_Key, Msg2}) ->
%% Timestamps can be modified by the replication layer, ignore them: %% Timestamps can be modified by the replication layer, ignore them:
Msg1#message{timestamp = 0} =:= Msg2#message{timestamp = 0}. Msg1#message{timestamp = 0} =:= Msg2#message{timestamp = 0}.
@ -734,7 +700,7 @@ message_eq(Msg1, {Key, Msg2}) ->
-spec verify_stream_effects(binary(), [node()], [{emqx_types:clientid(), ds_stream()}]) -> ok. -spec verify_stream_effects(binary(), [node()], [{emqx_types:clientid(), ds_stream()}]) -> ok.
verify_stream_effects(TestCase, Nodes0, L) -> verify_stream_effects(TestCase, Nodes0, L) ->
lists:foreach( Checked = lists:flatmap(
fun({ClientId, Stream}) -> fun({ClientId, Stream}) ->
Nodes = nodes_of_clientid(ClientId, Nodes0), Nodes = nodes_of_clientid(ClientId, Nodes0),
ct:pal("Nodes allocated for client ~p: ~p", [ClientId, Nodes]), ct:pal("Nodes allocated for client ~p: ~p", [ClientId, Nodes]),
@ -744,7 +710,8 @@ verify_stream_effects(TestCase, Nodes0, L) ->
[verify_stream_effects(TestCase, Node, ClientId, Stream) || Node <- Nodes] [verify_stream_effects(TestCase, Node, ClientId, Stream) || Node <- Nodes]
end, end,
L L
). ),
?defer_assert(?assertMatch([_ | _], Checked, "Some messages have been verified")).
-spec verify_stream_effects(binary(), node(), emqx_types:clientid(), ds_stream()) -> ok. -spec verify_stream_effects(binary(), node(), emqx_types:clientid(), ds_stream()) -> ok.
verify_stream_effects(TestCase, Node, ClientId, ExpectedStream) -> verify_stream_effects(TestCase, Node, ClientId, ExpectedStream) ->

View File

@ -162,7 +162,7 @@ interleave_test() ->
S2 = emqx_utils_stream:list([a, b, c, d]), S2 = emqx_utils_stream:list([a, b, c, d]),
?assertEqual( ?assertEqual(
[1, 2, a, b, 3, c, d], [1, 2, a, b, 3, c, d],
emqx_utils_stream:consume(emqx_utils_stream:interleave([{2, S1}, {2, S2}])) emqx_utils_stream:consume(emqx_utils_stream:interleave([{2, S1}, {2, S2}], true))
). ).
csv_test() -> csv_test() ->