polardbxengine/mysql-test/include/gr_find_a_primary.inc

79 lines
2.1 KiB
PHP

# ==== Purpose ====
#
# Finds a server with role PRIMARY.
#
# Result is placed on var:
# - $group_replication_primary_connection_out_var
# - $group_replication_found_primary_out_var
#
# It relies on $rpl_server_count to iterate through
# the group by connecting to the different servers
# and counting them.
#
# This iterates over all servers in the group every
# second until a timeout ocurrs or a primary is found.
#
# The current connection is preserved.
#
# ==== Usage ====
#
# --source include/gr_find_a_primary.inc
# if ($group_replication_found_primary_out_var)
# {
# --let $rpl_connection_name= $group_replication_primary_connection_out_var
# --source include/rpl_connection.inc
# # now on primary
# }
--let $include_filename= gr_find_a_primary.inc
--source include/begin_include_file.inc
# save the connection to reinstate it later
--let $_saved_current_connection= $CURRENT_CONNECTION
--let $group_replication_found_primary_out_var= 0
--let $group_replication_primary_connection_out_var=
# Let's wait 1 second between each try
--let $_retry_find_primary= $wait_timeout
while ($_retry_find_primary)
{
--let $_i_find_primary= $rpl_server_count
while ($_i_find_primary>0)
{
# connect to the server
--let $rpl_connection_name=server$_i_find_primary
--source include/rpl_connection.inc
let $_is_primary= `SELECT COUNT(*)=1 FROM performance_schema.global_status
WHERE VARIABLE_NAME = "group_replication_primary_member" AND
VARIABLE_VALUE = @@server_uuid`;
if ($_is_primary)
{
--let $group_replication_found_primary_out_var= 1
--let $group_replication_primary_connection_out_var= server$_i_find_primary
--let $_i_find_primary= 0
}
--dec $_i_find_primary
}
if (!$group_replication_found_primary_out_var)
{
--dec $_retry_find_primary
--sleep 1
}
if ($group_replication_found_primary_out_var)
{
--let $_retry_find_primary= 0
}
}
--let $rpl_connection_name=$_saved_current_connection
--source include/rpl_connection.inc
--let $include_filename= group_replication_wait_until_role.inc
--source include/end_include_file.inc