The information stored for each prepared statement would not be cleared
until the end of the session. This is a problem if the sessions last for a
very long time as the stored information is unused once a COM_STMT_CLOSE
has been received.
In addition to this, the session command response maps were not cleared
correctly if all backends had processed all session commands.
When the connection to the master is broken, the session is not configured
to use the read-only modes and the monitor can still connect to the
server, the connection will be closed and and error is sent to the
client. To leave some trace of this problem in the MaxScale logs, a
message should always be logged when a network error occurs.
The NULL values were not stored as NULL Avro values due to the fact that
the file format has no native NULL-ness for the basic types. To solve
this, all values must be stored as a union that contains the actual type
as well as the null type.
Unions were not implemented in the maxavro library but implementing means
simply recursing one level down.
If the query statement is wrongly treated as a table creation statement it
could cause a crash. To handle this, unknown SQL is now reported and the
processing is stopped early. This does not solve the root cause of the
problem but makes it possible to detect it in the future.
The admin files are now created with 640 permissions and automatically
created directories now properly set the permissions for the group as
well. All files and directories created by avrorouter and binlogrouter
also now correctly limit the read and write permissions only to the owner
and the group.
When a connection to a server is lost and the session command history is
disabled, the session will continue as long as at least one connection is
open. Previously the open connection calculation used the same code that
was used when a new session was created which only inspected the
configured server count instead of the actual open connection count.
The table creation was not detected as the function used to extract the
table name did not return the fully qualified names. Even if it did return
a fully qualified name, it wouldn't have been correctly processed.
When a read-only transaction fails due to a connection error, no message
would be logged. Also added an info level message for the case when a
backend connection would get closed before the session is in the correct
state and a debug assertion that the router session should never be closed
when the handleError method is called.
The debug assertion is wrong as the code was changed to prioritize hints
over the router target selection. Also removed the superficial check for
master, slave and relay master states as they are implied by the fact that
the connection is in use.
The collection of resultsets needs to be disabled by default when a
response is received to cover the cases where an error is returned.
The collection of results should also not be set for queries that do not
generate any responses.
When the setting up of filters for a session fails, the DCB is closed and
the client DCB's session pointer is set to NULL. This needs to be checked
in the schemarouter before the `m_client->session` pointer is used.
The act of setting the session pointer to NULL should not be necessary as
the session is freed once the reference count drops down to zero. Due to
the fact that changing this would require moderate changes in session code
means that it should not be done in a patch release as the risks are too
high.
By storing the data gathere by readwritesplit inside the session, the
protocol will be aware of the state of the LOAD DATA LOCAL INFILE
execution. This prevents misinterpretation of the data which previously
led to closed connections, effectively rendering LOAD DATA LOCAL INFILE
unusable.
This change is a temporary solution to a problem that needs to be solved
at the protocol level. The changes required to implement this are too big
to add into a bug fix release.
The offsets in the events were wrong if MaxScale was restarted in the
middle of a binlog. This was caused by the fact that the FDE event
contains information on binlog checksums which is required for a correct
interpretation of the binlog. The FDE event was only read when the binlog
was first opened when it needs to be read every time the binlog is opened.
As a JSON object can never start with the ERR prefix, it is safe to check
it for all requests. Also fixed the missing newline in the avrorouter
error message.
When the query queue does not contain a complete packet
(i.e. modutil_get_next_MySQL_packet return NULL), an informative dump of
how many bytes and what is stored is logged.
The protocol could leak memory in rare cases where several commands were
queued at the same time. Readwritesplit also didn't free the memory it
acquired via qc_get_table_names.
When a valid target was not found, no error message was logged by the
router. This would cause the "Routing the query failed. Session will be
closed." message to be logged with no explanation as to why the routing
failed.
In addition to the above-mentioned case, no message would be logged if the
target for a COM_STMT_FETCH was not in use.
If a session command produces a different result on the slave than it did
on the master, a warning is logged. This warning now also logs the query
that was being executed to make investigation of the problem easier.
Backend::execute_session_command would use the overridden write method
instead of the Backend::write method that it intended to use. This caused
session commands that did not expect a response to be in a state that
expected a result.
Also fixed RWBackend::write pass the response_type value to
Backend::write.
If the server sends a server shutdown error, it is safe for readwritesplit
to ignore it. When the TCP connection is closed, the router error handling
will discard the connection, optionally replacing it.
The number of arguments to createListener was incremented but the maximum
count was not. Also fixed the parameter types for createListener and
alterServer.
The server runtime alteration was broken by commit
c850336199c3c19508a3d280fb7000291d66b80c when it increased the maximum
argument count of the `alter server` command to 14.
Servers in MaxScale can encrypt the connections without client keys and
certificates. As keys and certificates are no longer required, the CA
certificate must always be initialized.
When a listener is created at runtime or SSL is being enabled for an
already created listener, the ssl_verify_peer_certificate parameter can
now be defined.
If a server responds when no response was expected, dump stored
statements. This should help deduce root causes of problems relating to
unexpected responses.
The code that selects the candidate backend always returned the root
master if the server bitmask contained the master bit. This should only be
done if the master bit is the only bit in the bitmask and when there are
other bits, the normal candidate selection code should be used.
Also added a query to the expanded test case to make sure the connection
actually works.
The two operations return different types of results and need to be
treated differently in order for them to be handled correctly in 2.2.
This fixes the unexpected internal state errors that happened in all 2.2
versions due to a wrong assumption made by readwritesplit. This fix is not
necessary for newer versions as the LOAD DATA LOCAL INFILE processing is
done with a simpler, and more robust, method.
