Merge pull request #13173 from kjellwinblad/kjell/pgsql_timestamp_encode_etc/EEC-1036

fix(pgsql connector): handle prepared statement already exists
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Kjell Winblad 2024-06-11 10:53:30 +02:00 committed by GitHub
commit 9d22089104
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2 changed files with 125 additions and 6 deletions

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@ -135,6 +135,7 @@ end_per_testcase(_Testcase, Config) ->
connect_and_clear_table(Config),
ok = snabbkaffe:stop(),
delete_bridge(Config),
emqx_common_test_helpers:call_janitor(),
ok.
%%------------------------------------------------------------------------------
@ -715,6 +716,87 @@ t_missing_table(Config) ->
connect_and_create_table(Config),
ok.
%% We test that we can handle when the prepared statement with the channel
%% name already exists in the connection instance when we try to make a new
%% prepared statement. It is unknown in which scenario this can happen but it
%% has been observed in a production log file.
%% See:
%% https://emqx.atlassian.net/browse/EEC-1036
t_prepared_statement_exists(Config) ->
Name = ?config(pgsql_name, Config),
BridgeType = ?config(pgsql_bridge_type, Config),
emqx_common_test_helpers:on_exit(fun() ->
meck:unload()
end),
MeckOpts = [passthrough, no_link, no_history, non_strict],
meck:new(emqx_postgresql, MeckOpts),
InsertPrepStatementDupAndThenRemoveMeck =
fun(Conn, Key, SQL, List) ->
meck:passthrough([Conn, Key, SQL, List]),
meck:delete(
epgsql,
parse2,
4
),
meck:passthrough([Conn, Key, SQL, List])
end,
meck:expect(
epgsql,
parse2,
InsertPrepStatementDupAndThenRemoveMeck
),
%% We should recover if the prepared statement name already exists in the
%% driver
?check_trace(
begin
?assertMatch({ok, _}, create_bridge(Config)),
?retry(
_Sleep = 1_000,
_Attempts = 20,
?assertMatch(
#{status := Status} when Status == connected,
emqx_bridge_v2:health_check(BridgeType, Name)
)
),
ok
end,
fun(Trace) ->
?assertMatch([_ | _], ?of_kind(pgsql_prepared_statement_exists, Trace)),
ok
end
),
InsertPrepStatementDup =
fun(Conn, Key, SQL, List) ->
meck:passthrough([Conn, Key, SQL, List]),
meck:passthrough([Conn, Key, SQL, List])
end,
meck:expect(
epgsql,
parse2,
InsertPrepStatementDup
),
%% We should get status disconnected if removing already existing statment don't help
?check_trace(
begin
?assertMatch({ok, _}, create_bridge(Config)),
?retry(
_Sleep = 1_000,
_Attempts = 20,
?assertMatch(
#{status := Status} when Status == disconnected,
emqx_bridge_v2:health_check(BridgeType, Name)
)
),
snabbkaffe_nemesis:cleanup(),
ok
end,
fun(Trace) ->
?assertMatch([_ | _], ?of_kind(pgsql_prepared_statement_exists, Trace)),
ok
end
),
ok.
t_table_removed(Config) ->
Name = ?config(pgsql_name, Config),
BridgeType = ?config(pgsql_bridge_type, Config),

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@ -268,7 +268,9 @@ close_prepared_statement(ChannelId, #{pool_name := PoolName} = State) ->
close_prepared_statement([WorkerPid | Rest], ChannelId, State) ->
%% We ignore errors since any error probably means that the
%% prepared statement doesn't exist.
%% prepared statement doesn't exist. If it exists when we try
%% to insert one with the same name, we will try to remove it
%% again anyway.
try ecpool_worker:client(WorkerPid) of
{ok, Conn} ->
Statement = get_templated_statement(ChannelId, State),
@ -689,17 +691,21 @@ do_prepare_sql([], _Prepares, LastSts) ->
{ok, LastSts}.
prepare_sql_to_conn(Conn, Prepares) ->
prepare_sql_to_conn(Conn, Prepares, #{}).
prepare_sql_to_conn(Conn, Prepares, #{}, 0).
prepare_sql_to_conn(Conn, [], Statements) when is_pid(Conn) ->
prepare_sql_to_conn(Conn, [], Statements, _Attempts) when is_pid(Conn) ->
{ok, Statements};
prepare_sql_to_conn(Conn, [{Key, {SQL, _RowTemplate}} | Rest], Statements) when is_pid(Conn) ->
prepare_sql_to_conn(Conn, [{_Key, _} | _Rest], _Statements, _MaxAttempts = 2) when is_pid(Conn) ->
failed_to_remove_prev_prepared_statement_error();
prepare_sql_to_conn(
Conn, [{Key, {SQL, _RowTemplate}} | Rest] = ToPrepare, Statements, Attempts
) when is_pid(Conn) ->
LogMeta = #{msg => "postgresql_prepare_statement", name => Key, sql => SQL},
?SLOG(info, LogMeta),
case epgsql:parse2(Conn, Key, SQL, []) of
{ok, Statement} ->
prepare_sql_to_conn(Conn, Rest, Statements#{Key => Statement});
{error, {error, error, _, undefined_table, _, _} = Error} ->
prepare_sql_to_conn(Conn, Rest, Statements#{Key => Statement}, 0);
{error, #error{severity = error, codename = undefined_table} = Error} ->
%% Target table is not created
?tp(pgsql_undefined_table, #{}),
LogMsg =
@ -709,6 +715,30 @@ prepare_sql_to_conn(Conn, [{Key, {SQL, _RowTemplate}} | Rest], Statements) when
),
?SLOG(error, LogMsg),
{error, undefined_table};
{error, #error{severity = error, codename = duplicate_prepared_statement}} = Error ->
?tp(pgsql_prepared_statement_exists, #{}),
LogMsg =
maps:merge(
LogMeta#{
msg => "postgresql_prepared_statment_with_same_name_already_exists",
explain => <<
"A prepared statement with the same name already "
"exists in the driver. Will attempt to remove the "
"previous prepared statement with the name and then "
"try again."
>>
},
translate_to_log_context(Error)
),
?SLOG(warning, LogMsg),
case epgsql:close(Conn, statement, Key) of
ok ->
?SLOG(info, #{msg => "pqsql_closed_statement_successfully"}),
prepare_sql_to_conn(Conn, ToPrepare, Statements, Attempts + 1);
{error, CloseError} ->
?SLOG(error, #{msg => "pqsql_close_statement_failed", cause => CloseError}),
failed_to_remove_prev_prepared_statement_error()
end;
{error, Error} ->
TranslatedError = translate_to_log_context(Error),
LogMsg =
@ -720,6 +750,13 @@ prepare_sql_to_conn(Conn, [{Key, {SQL, _RowTemplate}} | Rest], Statements) when
{error, export_error(TranslatedError)}
end.
failed_to_remove_prev_prepared_statement_error() ->
Msg =
("A previous prepared statement for the action already exists "
"but cannot be closed. Please, try to disable and then enable "
"the connector to resolve this issue."),
{error, unicode:characters_to_binary(Msg)}.
to_bin(Bin) when is_binary(Bin) ->
Bin;
to_bin(Atom) when is_atom(Atom) ->