If a server is removed from a service, readconnroute will not verify that
the server it is connected to is still the same root master. This fixes
the regression of MXS-1418.
A subset of the checks done at connection creation time need to be done at
query routing time. This guarantees that the connection is closed if the
server no longer qualifies as a valid candidate.
Added teset case that checks that a change in the replication topology
correctly breaks the connection.
The removal of a server from a service is intended to affect only new
sessions.
Added a test that checks that the connections are kept open even if the
server is removed from the service.
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.
The `user`, `password`, `version_string` and `weightby` values should be
allocated as a part of the service structure. This allows them to be
modified at runtime without having to worry about memory allocation
problems.
Although this removes the problem of reallocation, it still does not make
the updating of the strings thread-safe. This can cause invalid values to
be read from the service strings.
All routers except the binlogrouter now fully implement the JSON
diagnostic entry point. The binlogrouter needs to be handled in a separate
commit as it produces a large amount of diagnostic output.
The static capabilities declared in getCapabilities allows certain
capabilities to be queried before instances are created. The intended use
of this capability is to remove the need for the `is_internal_service`
function.
The routers no longer need to track the number of errors each DCB
receives. This is now done by the protocol modules.
The type of the DCB no longer needs to be checked in the handleError
implementation as the function is only called when a backend DCB fails.
The highwater and lowwater callbacks were never registered for the client
DCBs in the binlogrouter.
The DCB hangup callbacks were never called by the core and were replaced
with fake hangup events in an earlier version.
Removed unused spinlocks from DCBs, sessions and the MySQL protocol
structs. They were used in a context where only one thread has access to
the structure.
Removed unused member variables from DCBs.
All modules now declare a name for the module. This is name is added as a
prefix to all messages logged by a module. The prefix should help
determine which part of the system logs a message.
The MXS_MODULDE object now contains optinal pointers for functions
to be called att process and thread startup and shutdown. Since the
functions were added to the end, strictly speaking, all structures
would not have needed to have been modified, but better to be
explicit. In a subsequent change, these will be called.
C++ does not support flexible arrays, so for the time being C++
modules are restricted to 10 parameters. Better approach is to
factor out the parameters to a separate array and then just store
a pointer to that array in MXS_MODULE.
The MODULE_INFO is now the main object which is used by modules to convey
information to the MaxScale core. The MXS_MODULE name is more apt as it
now contains the actual module definition.
The old MODULES structure was moved into load_utils.c as an internal
implementation and was renamed so that it is not confused with the new
MODULE structure.
The modules are now declared with a common macro. This allows future
additions to the module loading process while also making the loaded
symbol name a constant.
This allows modules to only expose one entry point with a consistent
signature. In the future, this could be used to implement declarations of
module parameters.
The routeQuery() in readconnroute now checks for maintenance mode. If
the server is in maintenance, the session is closed, since this router
has no backend swapping capability.
The BACKEND structure in readconnroute is now replaced with the use of the
SERVER_REF structure of the service. This allows dynamic changes to the
list of servers to be made.
Common capabilities are now defined in routing.h. The common
capabilities can be defined using bits 0 - 15.
Router capabilities are defined using bits 16-31 and filter
capabilities (should there ever be such) using bits 32-47.
So, to find out the capabilities of a service you only need to
OR the capabilities of the router and all filters together.
For instance, if a single filter needs statement based routing,
then that is what is done.
- Since the capabilities are a bitmask, it is better if an unsigned
integral type is used.
- Since the function is part of an ABI, it is better if an explicit
size is used.
- 64-bits so that there also is room for independent filter
capabilities.
The general purpose stuff in skygw_utils.h was moved to utils.h
and the corresponding implementation from skygw_utils.cc to utils.c.
Includes updated accordingly.
Skygw_utils.h is now only used by log_manager and by mlist, which
is only used by log_manager. Consequently, skygw_utils.h was moved
to server/maxscale.
Utils.h needs a separate overhaul.
- All now include maxscale/cdefs.h as the very first file.
- MXS_[BEGIN|END]_DECLS added to all C-headers.
Strictly speaking not necessary for private headers, but
does not hurt either.
- Include guards moved to the very top of the file.
- #pragma once added.
