hcq/MaxScale
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

MXS-1203: Process multiple results correctly with readwritesplit

Browse Source 
The readwritesplit didn't correctly process the response packets that
contained more than one part of a multi-result response. By processing the
packets in a loop, this problem is avoided.

Removed some of the more "unique" ways of sending error messages in favor
of simply writing the error to the client DCB. This removes the need for
extra logic in the clientReply response handling.
This commit is contained in:
Markus Mäkelä
2017-04-03 14:44:08 +03:00
parent d7258fffd0
commit ea38d511e3
2 changed files with 79 additions and 82 deletions
Download Patch File Download Diff File Expand all files Collapse all files

72
server/modules/routing/readwritesplit/rwsplit_mysql.c
View File

@ -218,80 +218,46 @@ log_transaction_status(ROUTER_CLIENT_SES *rses, GWBUF *querybuf, qc_query_type_t
* @param qtype Query type
* @return bool indicating whether the session can continue
*/
bool
handle_target_is_all(route_target_t route_target,
ROUTER_INSTANCE *inst, ROUTER_CLIENT_SES *rses,
GWBUF *querybuf, int packet_type, qc_query_type_t qtype)
bool handle_target_is_all(route_target_t route_target, ROUTER_INSTANCE *inst,
ROUTER_CLIENT_SES *rses, GWBUF *querybuf,
int packet_type, qc_query_type_t qtype)
{
bool result;
bool result = false;
/** Multiple, conflicting routing target. Return error */
if (TARGET_IS_MASTER(route_target) || TARGET_IS_SLAVE(route_target))
{
backend_ref_t *bref = rses->rses_backend_ref;
/**
* Conflicting routing targets. Return an error to the client.
*/
/* NOTE: modutil_get_query is MySQL specific */
char *query_str = modutil_get_query(querybuf);
char *qtype_str = qc_typemask_to_string(qtype);
/* NOTE: packet_type is MySQL specific */
MXS_ERROR("Can't route %s:%s:\"%s\". SELECT with session data "
"modification is not supported if configuration parameter "
"use_sql_variables_in=all .", STRPACKETTYPE(packet_type),
qtype_str, (query_str == NULL ? "(empty)" : query_str));
MXS_INFO("Unable to route the query without losing session data "
"modification from other servers. <");
GWBUF *errbuf = modutil_create_mysql_err_msg(1, 0, 1064, "42000",
"Routing query to backend failed. "
"See the error log for further details.");
while (bref != NULL && !BREF_IS_IN_USE(bref))
if (errbuf)
{
bref++;
}
if (bref != NULL && BREF_IS_IN_USE(bref))
{
/** Create and add MySQL error to eventqueue */
modutil_reply_parse_error(bref->bref_dcb,
MXS_STRDUP_A("Routing query to backend failed. "
"See the error log for further "
"details."), 0);
rses->client_dcb->func.write(rses->client_dcb, errbuf);
result = true;
}
else
{
/**
* If there were no available backend references
* available return false - session will be closed
*/
MXS_ERROR("Sending error message to client "
"failed. Router doesn't have any "
"available backends. Session will be "
"closed.");
result = false;
}
/* Test shouldn't be needed */
if (query_str)
{
MXS_FREE(query_str);
}
if (qtype_str)
{
MXS_FREE(qtype_str);
}
return result;
}
/**
* It is not sure if the session command in question requires
* response. Statement is examined in route_session_write.
* Router locking is done inside the function.
*/
result = route_session_write(rses, gwbuf_clone(querybuf), inst,
packet_type, qtype);
if (result)
MXS_FREE(query_str);
MXS_FREE(qtype_str);
}
else if (route_session_write(rses, gwbuf_clone(querybuf), inst, packet_type, qtype))
{
result = true;
atomic_add_uint64(&inst->stats.n_all, 1);
}
return result;
}