The readqueue should never be explicitly assigned and should only ever be
appended to. This guarantees that the packets are read and processed in
the correct order.
Also removed an unused function that deals with the readqueue
manipulation.
When packets were routed individually, the qualification for the
persistent pool was done before the current command was updated. In
addition to this, the previous commit doesn't seem like it can even build.
The statement tracking was given the same buffer multiple times when a
large packet was spread across multiple buffers when a router with
RCAP_TYPE_STMT_INPUT was present.
The command tracking packet processing is redundant for routers that
require RCAP_TYPE_STMT as the same processing is done later when the
buffer is split into packets and routed. By using the split packets, the
protocol module can simplify the command tracking by a great deal for most
routers.
Sending an error to the client allows the connector to show more
information to the user when the DCB is closed due to a reason internal to
MaxScale.
The error message states that the connection was killed by MaxScale to
distinct it from the error sent by the server. The error number and SQL
state are still the same as both errors should be treated the same way.
This builds on commit 1287b0e595a5f99026f66df7eeaef091b8ffc774 and cleans
up the original code. This fixes a bug introduced in the aforementioned
commit and cleans up the code.
The authentication code assumed that the initial request only had
authentication related data. This is not true if the client library
predicts that the authentication will succeed and it sends a query right
after it sends the authentication data.
The authentication phase expects full packets. If the packets aren't
complete a debug assertion would get hit. To detect this, the result of
the extracted buffer needs to be checked.
KILL commands are now sent to the backends in an asynchronous manner. As
the LocalClient class is used to connect to the servers, this will cause
an extra connection to be created on top of the original connections
created by the session.
If the user does not have the permissions to execute the KILL, the error
message is currently lost. This could be solved by adding a "result
handler" into the LocalClient class which is called with the result.
If the client sends data before authentication is complete, it must not be
discarded and it needs to be processed like as if it was sent in a
separate network packet.
The enums exposed by the connector are not intended to be used by the
users of the library. The fact that the protocol, and other, modules used
it was in violation of how the library is intended to be used.
Adding an internal mapping into MaxScale also removes some of the
dependencies that the core has on the connector.
Cleaned up the MaxScale version of the mysql.h header by removing all
unused includes. This revealed a large amount of dependencies on these
removed includes in other files which needed to be fixed.
Also sorted all includes in changed files by type and alphabetical
order. Removed explicit revision history from modified files.
When a session is being closed in a controlled manner, i.e. a COM_QUIT is
received from the client, it is possible to deduce from this fact that the
backend connections are very likely to be idle. This can be used as an
additional qualification that must be met by all connections before they
can be candidates for connection pooling.
This assumption will not hold with batched and asynchronous queries. In
this case it is possible that the COM_QUIT is received from the client
before even the first result from the backend is read. For this to work,
the protocol module would need to track the number and state of expected
responses.
When a LOAD DATA LOCAL INFILE is done, the last packet is an empty packet
which does not contain the command byte. Some parts of the MySQL protocol
modules expected that a command is always present. The proper way to
handle this is to use the mxs_mysql_get_command function which does bounds
checking.
If a connection has not been fully established (i.e. authentication has
been completed) then it should not be considered as a connection pool
candidate.
The initial setting of sql_mode affects how MaxScale initially
behaves with respect to autocommit.
When 'set sql_mode=[default|oracle];" is encountered, the query
classifier and autocommit modes are adjusted accordingly.
That's where it belongs as it is only the mysql client protocol that
will use it. It's a bit unfortunate that the qc test program compare
now needs to include a file from a protocol module directory, but
the fact is that the query classifier implementation and the test
programs should actually be *under* the mysql client protocol module.
The parser is needed not only by mysql_client but also by the test
program of the qc-plugins, so it need to be available someplace
common.
Not that nice that both a qc-component and mysql_client will include
stuff from server/core/maxscale, but at least temporarily ok.
SetSqlModeParser is a custom parser for detecting "SET SQL_MODE=..."
statements. It will be used in mysql_client and the result will be
used for updating the sql_mode of a session (that is to be added).
Thereafter, whenever a statement arrives, the value of that sql_mode
will be used for setting the mode of the query_classifier.
A custom parser for detecting "set sql_mode=ORACLE" is needed
and writing that is C++ is more convenient than writing it in
C. Consequently, so as to be able to use that parser, mysql_client
must be compiled as C++.
With this change, it is no longer possible that the server version
is deallocated at the very moment it is read. There is still a race,
but it's mostly harmless.
The template class wraps a HashMap such that only a few operations
are allowed. Usage requires specializing a RegistryTraits class
template for each entry type.
If a connection has not been fully established (i.e. authentication has
been completed) then it should not be considered as a connection pool
candidate.
This was originally removed, since it was checking the same word
twice. However, the parsing is clearer with it and the cost is only
paid when the KILL is detected, which is very rare.
Also, fix some incorrect parsing.
The text-version of "KILL CONNECTION" command is now supported. To keep the
overhead low, only minimal parsing is done on the query. The query
needs to start in the beginning of the mysql-packet, have no comments
and have limited whitespace as the total length of the query is limited.
Both "KILL 123" and "KILL CONNECTION 123" are accepted.
"KILL QUERY 123" is also accepted but not acted on, as it requires larger
changes.
