MaxScale can now be started with an empty configuration file and services
can be created at runtime. Filters cannot yet be created at runtime so
complete runtime creation of configurations is not yet possible.
The causal read queries were performed also when the target server was the
master. The extra functionality of the causal reads is only needed on
slaves.
Adjusted the test case to require GTID replication.
The configuration used the wrong parameter name. The test also did not
explicitly enable tracking of the last_gtid variable which caused it to
fail if it wasn't already on.
By reading the configuration as late as possible, we allow the objects to
be created in an environment which is nearly identical to the environment
that is present at runtime.
This change makes it possible to execute worker tasks in the instance
creation functions of various modules. The avrorouter in particular
depended on being able to queue worker tasks on startup.
The initialization and starting of the housekeeper is now done
separately. This allows housekeeper tasks to be created when the services
are being created while still preventing the execution of the task before
the startup is complete.
The MariaDB 10.3.8 release fixes the use of last_gtid as a value for
session_track_system_variables. This means that the test can be enabled if
the backends are new enough.
The test failed because router instances are now created when the service
is allocated. In addition to this, a debug assertion was hit when a
service was freed if the router instance creation failed.
Added commands for creating and destroying services. The create command
allows server and filter relationships to be defined but they are not yet
processed by MaxScale. This will be done once the use of filters is made
dynamic.
Services can now be destroyed if they have no active listeners and they
are not linked to servers. When these conditions are met, the service will
be destroyed when the last session for the service is closed.
The closing of a service will close all listeners that were once assigned
to the service. This allows closing of the ports at runtime which
previously was done only on shutdown.
Exposed the command through the REST API but not through MaxAdmin as it is
deprecated.
When a service is freed, it will free all of its listeners causing their
respective DCBs to be closed. This requires that listeners can be removed
from the worker DCB list.
The runtime configuration JSON validation now allows multiple
relationships to be verified at one time. This makes it easier to validate
all objects using the same framework.
When a listener is removed from a service, it should also be removed from
any workers it has been added to. This guarantees that if the opening of
the listener was successful, no requests will be accepted on it after the
removal of the listener.
As all connections should be accepted via dcb_accept, it is the optimal
place to calculate how many open client connections per service there
are. The decrementation should be done when the session is closed instead
of when the call to dcb_close for the client DCB is done. This allows the
client count to be the absolute reference count that sessions have to a
service.
The current client count is a duplicate counter that should match the
n_current value in SERVICE_STATS. The former does differ from the latter
in that it does the incrementation when the client DCB is accepted instead
of when the session is created.
By creating the router instance as a part of the service allocation
process, we are guaranteed that either the creation of the service is
completely successful or it fails. This should make runtime creation of
services easier.
As we know that the test doesn't rely on absolute binlog positions, we can
force synchronization by creating a table on the master and waiting until
that table is replicated to all slaves.
Add support for binary protocol prepared statements for schemarouter.
This implementation doesn't yet attempt to handle all the edge cases.
Prepared statements are routed to the server that contains the affected
tables, the internal id from the server is then mapped to the session
command id that is inceremented for each prepared statement. This unique
session command id is returned to the client because internal id given
by server might be same around different servers and this way it is
possible to keep track of them and route them to the right servers when
executed.
-Wunused-result warning in test_logthrottling.cc was causing error when
trying to build MaxScale from source. This warning can be silenced with by
putting the function triggering the warning in if-clause.
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.
By aborting the process if memory runs out when a buffer needs to be made
contiguous, we rule out other, more subtle, errors. Failing as soon as a
possible when memory allocation fails gives better error messages.
Streamlined the test to perform as much testing as fast as possible. The
gradual ramp up did not provide any concrete benefits compared to testing
everything at once.
Replaced structures with C++11 alternatives where possible and removed
unused, redundant or dead code.