These parameters usually must be the same across all cluster nodes and
therefore must be set only via global configuration and always passed as
a list of postgres arguments (via pg_ctl) to make it not possible
accidentally change them by 'ALTER SYSTEM'
Originally Exhibitor was supported in the ZooKeeper class and
configuration for Exhibitor was taken also from `zookeeper` section in
the yaml config file. In fact, Exhibitor just extends ZooKeeper and now
it is reflected in the code and also Exhibitor got it's own section in
the config.yaml file. It will make it easier to configure Exhibitor
hosts and port via environment variables when PR#211 will be merged.
And some other tricks with overriding handle_one_request and finish
methods from the parent class which were necessary only to make OPTIONS
request from haproxy work with python2, but in fact it was still not
working with python3. Instead of doing all the magic we should simply
give to haproxy what it wants to get: HTTP response code and nothing
more.
where it is not necessary (test_ha, test_ctl, etc...)
It will simplyfy further refactoring and make it possible to install
implementations of AbstractDCS independant of each other.
Originally we were passing postgresql options as an argument of `pg_ctl
start`. It was nice and convenient because doesn't require to touch
configuration files but this method has one significant drawback: it
wasn't possible to change values of options which were passed as an
arguments without restart (event for the case when option reqires only
reload). Instead of doing that (passing options as arguments) we will:
1) rename original postgresql.conf to postgresql-base.conf
2) write options into postgresql.conf which has `include
'postgresql-base.conf'` on the the third line after comment that this
file is generated by Patroni and you should not change it manually
3) listen_addresses and port are still passed as an arguments to the
pg_ctl (just to be foolproof against ALTER SYSTEM set port to 'random')
In addition to that this commit makes some attributes of `Postgresql`
class private (prefixes them with _)
Somehow when you import only urllib3 it's not possible work with
urllib3.exceptions.HTTPError exception (it looks like it is imported
from some other place. from urllib3.exceptions import HTTPError solves
the problem.
A Patroni configuration should be enough for Patronictl
The previous dcs_api url style is still supported.
To remove duplicate magic variables a DCS_DEFAULTS was introduced.
Some behaviour has changed: If you do not specify a DCS at all
(not in configuration, not on commandline, not in environment), it will
not default to etcd://localhost:4001
More test coverage for patronictl
Previously we explicitly injected a replication record into pg_hba.conf.
This doesn't allow users to explicitly write their configurations.
This change will just write the lines specified by the user.
Mostly this tag is necessary to give a hint to load balancer
auto-configuration tool that node should not be included into
LB configuration.
In addition to that Patroni also should not return status_code=200
for a health check if the tag is present and value is not `False`.
Previously we explicitly injected a replication record into pg_hba.conf.
This doesn't allow users to explicitly write their configurations.
This change will just write the lines specified by the user.
