The server state information should be persisted even if a controlled
shutdown is done. This will allow the monitor to retain the server state
information across a restart.
The MySQL monitor stores the server states in a backup file which can be
used to restore the state of the servers even if MaxScale is stoppen in an
uncontrolled fashion.
The hintrouter is now in principle capable of routing requests
to the master or to some slave (in a round robin fashion) based
upon hints set by some earlier filter.
Note that as the router is completely oblivious of transaction
boundaries, using it with transactions and autocommit being off
will not make anyone happy.
Recognizing transaction boundaries using regexes and then pinning
the server until transaction commit would be needed.
Move most of the functions under the filter or session-classes.
Class definitions moved to a header file. General cleanup. Some features
are still incoming.
The filter now accepts (in addition to the old "match" and "server")
parameters of the form "matchN" and "serverN", where N is a decimal
number with two digits, i.e 01, 02, 03 .. 20. When routing queries,
the regural expressions will be tested one by one, and the servers
from the first match will be added as hints. Also, a single "server"-
setting may contain multiple servers separated by ','. The server
names are not verified to be actual servers, this is up to the user.
This is a list of servers, separated by commas. When queried as a
config setting, returns a null-terminated array of SERVER*:s. The
commit includes a serverlist parsing function, which should probably
be used anywhere a similarly formed string is parsed.
The core now provides a simple function to close a session. This removes
the need for the modules to directly call the API entry points when the
session should be closed. It is also in line with the style that other
objects, namely the DCBs, use. This makes the new session_close very
similar to dcb_close.
The client protocol module can resolve whether a password was used based
on the information the authenticators gather before authentication is
done. It uses the authentication token length as the basis on which it
makes the decision.
The users were deleted before each individual server was queried. This
caused authentication to fail if the authentication data was loaded from
multiple servers.
The client connection and the server listener sockets used largely similar
code. Combining them allows for simpler protocol code.
Cleaned up parts of the DCB listener creation and moved the parsing of the
network binding configuration to a higher level.
The socket creation code in mysql_backend.c wasn't MySQL specific and it
could be used for all non-blocking network connections. Thus, it makes
sense to move it to a common file where other protocol modules can use
it.
The address resolution code now uses `getaddrinfo` to resolve all
addresses instead of manually handling wildcard hosts. This allows the
same code to be used for all addresses.
Both the listeners and servers now support IPv6 addresses.
The namedserverfilter does not yet use the new structures and needs to be
fixed in a following commit.
Thread-safe version of strerror; thread local buffer used for storing
the message. The performance penalty of a thread local buffer is not
likely to be significant, since this is only called in an error
situation that anyway is likely to interrupt the normal processing.
The SQLite database is now always created on disk. This will remove the
need to dump the database users from the in-memory database to the
persisted on-disk database.
This change will also make the authentication compatible with older SQLite
implementations which lack the URI-based database strings found in newer
versions.
The authenticators should have a similar way to print diagnostic
information as filter and routers do. This allows the authenticators to
print the users in their own format.
In the future, all the diagnostic entry points should be changed so that
they return a structure that contains the information in a standard
form. This information can then be formatted in different ways by other
modules.
MariaDB and others match grants first by exact hostname/IP and then by
wildcard. If there are no exact matches, the wildcard grant should be
picked. This can be tested by having different passwords for localhost and
remote address.
The SQLite based authentication should first check for an exact match and
then only after that should it try to match the hostname to a wildcard
grant.
The get_users function now combines the functionality of the old get_users
and get_all_users. This removes large parts of similar code.
Removed the listener resources as MySQLAuth was the only one that used it.
The user data is now stored inside a SQLite3 database. By storing the data
inside a database, we remove the restriction that the previous hashtable
based implementation had.
Currently the only situation where a user needs to be authenticated after
the initial authentication is when a COM_CHANGE_USER is being
executed. This was previously handled by directly calling a function in
the MySQLAuth authenticator.
The new entry in the API of the authenticators is very specific to MySQL
and should be reviewed once other protocols are added.
When the real root master server went down, it still received the master
status bit due to how the replication tree was built. The bit should only
be set for servers that are running.
Also fixed a false state change event when the master status bit was
manually cleared from the downed root master server.
