https://emqx.atlassian.net/browse/EMQX-8445
Currently the bridge client’s client ID is prefixed with the resource
ID.
Sometimes it’s useful for users to have control of this prefix,
e.g. prefix based ACL rules in the target broker.
An infinite loop was triggered in the mysql connector when a query
used a prepared statement key that was not among the defined prepared
statements on start. We now check that the key is defined among the
prepared statements before recursing. It seems that this bug was never
triggered in any production code flow and simply found while writing
tests.
An error return spell fix is also included as well as a FIXME comment
regarding running mysql:prepare and not distinguishing between
transient failures and syntax errors. Syntax errors should not be
retried.
Testcase `t_log_file` was flapping when run happened to pass through
boundary of a second. Archive files' `ctime`s could differ between
consecutive archive downloads.
reason: 'ce' (Community Edition) is only for internal use,
when it comes to user/customer facing descriptions,
we should use Opensource edition and Enterprise edition.
Similary, for user/customer facing shell prompt,
use `v` for Opensource edition and `e` for Enterprise
Given the implicit convention that an egress bridge containing the
`local_topic` config will forward messages without the need for a rule
action, this was added to avoid needing a rule action.
When `system_monitor`'s application is loaded, it sets a default
hostname:
```erlang
1> application:get_env(system_monitor, db_hostname).
undefined
2> application:load(system_monitor).
ok
3> application:get_env(system_monitor, db_hostname).
{ok,"localhost"}
```
And that makes tests crash when somehow it gets loaded.
By having a semantic `enable` field, we could avoid starting this
application by checking if the hostname is filled or not.
```
=ERROR REPORT==== 1-Dec-2022::13:57:20.855070 ===
** Generic server <0.7646.3> terminating
** Last message in was {command,epgsql_cmd_connect,
#{codecs => [],database => "postgres",
host => [],
password =>
#Fun<epgsql_cmd_connect.0.29916615>,
port => 5432,timeout => 5000,
username => "system_monitor"}}
** When Server state == {state,undefined,undefined,<<>>,undefined,on_message,
undefined,
{[],[]},
undefined,undefined,undefined,undefined,[],
information_redacted,[],undefined,undefined,
undefined,undefined,undefined,#{}}
** Reason for termination ==
** {badarg,
[{gen_tcp,connect_0,4,[{file,"gen_tcp.erl"},{line,207}]},
{epgsql_cmd_connect,open_socket,2,
[{file,
"/emqx/_build/default/lib/epgsql/src/commands/epgsql_cmd_connect.erl"},
{line,94}]},
{epgsql_cmd_connect,execute,2,
[{file,
"/emqx/_build/default/lib/epgsql/src/commands/epgsql_cmd_connect.erl"},
{line,54}]},
{epgsql_sock,command_exec,4,
[{file,"/emqx/_build/default/lib/epgsql/src/epgsql_sock.erl"},
{line,338}]},
{gen_server,try_handle_call,4,[{file,"gen_server.erl"},{line,721}]},
{gen_server,handle_msg,6,[{file,"gen_server.erl"},{line,750}]},
{proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,226}]}]}
** Client system_monitor_pg stacktrace
** [{gen,do_call,4,[{file,"gen.erl"},{line,214}]},
{gen_server,call,3,[{file,"gen_server.erl"},{line,243}]},
{epgsql,call_connect,2,
[{file,"/emqx/_build/default/lib/epgsql/src/epgsql.erl"},
{line,203}]},
{system_monitor_pg,connect,0,
[{file,"/emqx/_build/default/lib/system_monitor/src/system_monitor_pg.erl"},
{line,151}]},
{system_monitor_pg,initialize,0,
[{file,"/emqx/_build/default/lib/system_monitor/src/system_monitor_pg.erl"},
{line,142}]},
{system_monitor_pg,handle_info,2,
[{file,"/emqx/_build/default/lib/system_monitor/src/system_monitor_pg.erl"},
{line,92}]},
{gen_server,try_dispatch,4,[{file,"gen_server.erl"},{line,695}]},
{gen_server,handle_msg,6,[{file,"gen_server.erl"},{line,771}]},
{proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,226}]}]
=CRASH REPORT==== 1-Dec-2022::13:57:20.855697 ===
crasher:
initial call: epgsql_sock:init/1
pid: <0.7646.3>
registered_name: []
exception exit: badarg
in function gen_tcp:connect_0/4 (gen_tcp.erl, line 207)
in call from epgsql_cmd_connect:open_socket/2 (/emqx/_build/default/lib/epgsql/src/commands/epgsql_cmd_connect.erl, line 94)
in call from epgsql_cmd_connect:execute/2 (/emqx/_build/default/lib/epgsql/src/commands/epgsql_cmd_connect.erl, line 54)
in call from epgsql_sock:command_exec/4 (/emqx/_build/default/lib/epgsql/src/epgsql_sock.erl, line 338)
in call from gen_server:try_handle_call/4 (gen_server.erl, line 721)
in call from gen_server:handle_msg/6 (gen_server.erl, line 750)
ancestors: [system_monitor_pg,system_monitor2_sup,system_monitor_sup,
<0.4297.3>]
message_queue_len: 0
messages: []
links: [<0.4303.3>]
dictionary: []
trap_exit: false
status: running
heap_size: 1598
stack_size: 29
reductions: 734
neighbours:
```
