* Lookup function installation
Due to reusing a previous database connection without closing it, lookup
function installation process was skipping the first database in the
list, installing twice into postgres db instead. To prevent that, make
internal initDbConnWithName to overwrite a connection object, and return
the same object only from initDbConn, which is sort of public interface.
Another solution for this would be to modify initDbConnWithName to
return a connection object and then generate one temporary connection
for each db. It sound feasible but after one attempt it seems it
requires a bit more changes around (init, close connections) and
doesn't bring anything significantly better on the table. In case if
some future changes will prove this wrong, do not hesitate to refactor.
Change retry strategy to more insistive one, namely:
* retry on the next sync even if we failed to process one database and
install pooler appliance.
* perform the whole installation unconditionally on update, since the
list of target databases could be changed.
And for the sake of making it even more robust, also log the case when
operator decides to skip installation.
Extend connection pooler e2e test with verification that all dbs have
required schema installed.
Right now there are no readiness probes defined for connection pooler,
which means after a pod restart there is a short time window (between a
container start and connection pooler starting listening to a socket)
when a service can send queries to a new pod, but connection will be
refused. The pooler container is rather lightweight and it start to
listen immediately, so the time window is small, but still.
To fix this add a readiness probe for tcp socket opened by connection
pooler.
Extend infrastructure roles handling
Postgres Operator uses infrastructure roles to provide access to a database for
external users e.g. for monitoring purposes. Such infrastructure roles are
expected to be present in the form of k8s secrets with the following content:
inrole1: some_encrypted_role
password1: some_encrypted_password
user1: some_entrypted_name
inrole2: some_encrypted_role
password2: some_encrypted_password
user2: some_entrypted_name
The format of this content is implied implicitly and not flexible enough. In
case if we do not have possibility to change the format of a secret we want to
use in the Operator, we need to recreate it in this format.
To address this lets make the format of secret content explicitly. The idea is
to introduce a new configuration option for the Operator.
infrastructure_roles_secrets:
- secretname: k8s_secret_name
userkey: some_encrypted_name
passwordkey: some_encrypted_password
rolekey: some_encrypted_role
- secretname: k8s_secret_name
userkey: some_encrypted_name
passwordkey: some_encrypted_password
rolekey: some_encrypted_role
This would allow Operator to use any avalable secrets to prepare infrastructure
roles. To make it backward compatible simulate the old behaviour if the new
option is not present.
The new configuration option is intended be used mainly from CRD, but it's also
available via Operator ConfigMap in a limited fashion. For ConfigMap one can
put there only a string with one secret definition in the following format (as
a string):
infrastructure_roles_secrets: |
secretname: k8s_secret_name,
userkey: some_encrypted_name,
passwordkey: some_encrypted_password,
rolekey: some_encrypted_role
Note than only one secret could be specified this way, no multiple secrets are
allowed.
Eventually the resulting list of infrastructure roles would be a total sum of
all supported ways to describe it, namely legacy via
infrastructure_roles_secret_name and infrastructure_roles_secrets from both
ConfigMap and CRD.
There is a possibility to pass nil as one of the specs and an empty spec
into syncConnectionPooler. In this case it will perfom a syncronization
because nil != empty struct. Avoid such cases and make it testable by
returning list of syncronization reasons on top together with the final
error.
* Protected and system users can't be a connection pool user
It's not supported, neither it's a best practice. Also fix potential null
pointer access. For protected users it makes sense by intent of protecting this
users (e.g. from being overriden or used as something else than supposed). For
system users the reason is the same as for superuser, it's about replicastion
user and it's under patroni control.
This is implemented on both levels, operator config and postgresql manifest.
For the latter we just use default name in this case, assuming that operator
config is always correct. For the former, since it's a serious
misconfiguration, operator panics.
Connection pooler support
Add support for a connection pooler. The idea is to make it generic enough to
be able to switch between different implementations (e.g. pgbouncer or
odyssey). Operator needs to create a deployment with pooler and a service for
it to access.
For connection pool to work properly, a database needs to be prepared by
operator, namely a separate user have to be created with an access to an
installed lookup function (to fetch credential for other users).
This setups is supposed to be used only by robot/application users. Usually a
connection pool implementation is more CPU bounded, so it makes sense to create
several pods for connection pool with more emphasize on cpu resources. At the
moment there are no special affinity or tolerations assigned to bring those
pods closer to the database. For availability purposes minimal number of
connection pool pods is 2, ideally they have to be distributed between
different nodes/AZ, but it's not enforced in the operator itself. Available
configuration supposed to be ergonomic and in the normal case require minimum
changes to a manifest to enable connection pool. To have more control over the
configuration and functionality on the pool side one can customize the
corresponding docker image.
Co-authored-by: Felix Kunde <felix-kunde@gmx.de>
* add json:omitempty option to ClusterDomain
* Add default value for ClusterDomain
Unfortunately, omitempty in operator configuration CRD doesn't mean that
defauls from operator config object will be picked up automatically.
Make sure that ClusterDomain default is specified, so that even when
someone will set cluster_domain = "", it will be overwritted with a
default value.
Co-authored-by: mlu42 <mlu42pro@gmail.com>
For optimization purposes operator was creating a cache map to remember
if service accounts and role binding was deployed to a namespace. This
could lead to a problem, when a namespace was deleted, since this
cache was not synchronized. For the sake of correctness remove the
cache, and check every time if required service account and rbac is
present. In the normal case this introduces an overhead of two API calls
per an event (one to get a service accounts, one to get a role binding),
which should not be a problem, unless proven otherwise.
* And attempt to build with modules and remove glide
* new tools.go file to get code-generator dependency + updated codegen + remove Glide files and update docs
Override clone s3 bucket path
Add possibility to use a custom s3 bucket path for cloning a cluster
from an arbitrary bucket (e.g. from another k8s cluster). For that
a new config options is introduced `s3_wal_path`, that should point
to a location that spilo would understand.
Add possibility to mount a tmpfs volume to /dev/shm to avoid issues like
[this](https://github.com/docker-library/postgres/issues/416). To achieve that
two new options were introduced:
* `enableShmVolume` to PostgreSQL manifest, to specify whether or not mount
this volume per database cluster
* `enable_shm_volume` to operator configuration, to specify whether or not mount
per operator.
The first one, `enableShmVolume` takes precedence to allow us to be more flexible.
To improve the documentation we need to split it into smaller parts:
* quickstart (in the readme)
* general concepts
* tutorials
* how to
* references
And then add the missing information. So far I just split the existing
documentation and left references almost empty. I assume that references
may duplicate the rest of the documentation in a way that the doc will
have references to this section, that contains all the formal details.
Dmitry Dolgov