This commit follows up the work in Kolla to provide deploy and configure the
Prometheus blackbox exporter.

An example blackbox-exporter module has been added (disabled by default)
called os_endpoint. This allows for the probing of endpoints over HTTP
and HTTPS. This can be used to monitor that OpenStack endpoints return a status
code of either 200 or 300, and the word 'versions' in the payload.

This change introduces a new variable `prometheus_blackbox_exporter_endpoints`.
Currently no defaults are specified because the configuration is heavily
dependent on the deployment.

Co-authored-by: Jack Heskett <Jack.Heskett@gresearch.co.uk>
Change-Id: I36ad4961078d90e2fd70c9a3368f5157d6fd89cd

Currently, we have a lot of logic for checking if a handler should run,
depending on whether config files have changed and whether the
container configuration has changed. As rm_work pointed out during
the recent haproxy refactor, these conditionals are typically
unnecessary - we can rely on Ansible's handler notification system
to only trigger handlers when they need to run. This removes a lot
of error prone code.

This patch removes conditional handler logic for all services. It is
important to ensure that we no longer trigger handlers when unnecessary,
because without these checks in place it will trigger a restart of the
containers.

Implements: blueprint simplify-handlers

Change-Id: I4f1aa03e9a9faaf8aecd556dfeafdb834042e4cd

Add become to copy cloud config file for openstack exporter.

Change-Id: I4c0c325e9dd1f41ca2c4667178a4fa674fa23ec5
Closes-Bug: #1824098

Several config file permissions are incorrect on the host. In general,
files should be 0660, and directories and executables 0770.

Change-Id: Id276ac1864f280554e98b937f2845bb424d521de
Closes-Bug: #1821579

This patch implements the initial support for the
openstack-exporter[0] in the kolla-ansible
prometheus monitoring system.

The configuration and prechecks are reused from the other
exporters and a new template is provided for generating
a os-client-config file required by the exporter.

The default scrape interval is 60 seconds, but it can
be extended via a configuration option.

[0] https://github.com/Linaro/openstack-exporter

Change-Id: I4a34c4bb56e74b5cd544972cbd6540d9acb6e4a1

This is required to support execution as a non-root user.

Change-Id: I60d224407c2828d6b9f1701f7637385a25fbcced
Closes-Bug: #1809233

Trivial-Fix
Change-Id: Iea123c32981309698bd644229dc1525fa671a487

This patch extends the configuration task for prometheus
to allow the operator to pass a(set) of prometheus alert
rules files, that will be used by alertmanager to produce
alerts.

This functionality is only enabled when the prometheus-alertmanager
service is enabled.

Change-Id: I882759c3774f43640631c1058f8a9cb24e7a60d2
Closes-Bug: #1776529
Signed-off-by: Jorge Niedbalski <jorge.niedbalski@linaro.org>

Change https://review.openstack.org/#/c/571826/4/


introduced the usage of merge_yaml for rendering the
prometheus-alertmanager.yml configuration.

However the merge_yaml module doesn't do a deep copy of >=
second level properties, so it doesn't works for
most configurations.

Bug: #1786077
Change-Id: I35297c6e2a3800582fb1fd3782a5d93558562b1d
Signed-off-by: Jorge Niedbalski <jorge.niedbalski@linaro.org>

This commit is the final commit to apply resource-constraints
to all OpenStack services.

Depends-on: I39004f54281f97d53dfa4b1dbcf248650ad6f186
Change-Id: I072d69be9698be54775cb0ae286ea2b6ed78776c
Implements: blueprint resource-constraints

This patch extends the prometheus role for being able
to deploy the prometheus-alertmanager[0] container.

The variable enable_prometheus_alertmanager
decides if the container should be deployed and enabled.

If enabled, the following configuration and actions are performed:

- The alerting section on the prometheus-server configuration
is added pointing the prometheus-alertmanager host group as targets.

- HAProxy is configured to load-balance over the prometheus-alertmanager
host group. (external/internal).

Please note that a default (dummy) configuration is provided, that
allows the service to start, the operator should extend it via a node custom config

[0] https://github.com/openstack/kolla/tree/master/docker/prometheus/prometheus-alertmanager



Change-Id: I3a13342c67744a278cc8d52900a913c3ccc452ae
Closes-Bug: 1774725
Signed-off-by: Jorge Niedbalski <jorge.niedbalski@linaro.org>

Add become to all tasks that use the module "kolla_docker"

Change-Id: I4309c4011687b88ec31d739fd8f834fe2326ff10
Partial-Implements: blueprint ansible-specific-task-become

In change I78cb60168aaa40bb6439198283546b7faf33917c, action was changed
to kolla_action, and serial to kolla_serial, to avoid Ansible warnings
due to use of reserved keywords. In that change, some keywords were
missed, and some changes that were merged since then have not switched
to the new variables. This change fixes all current instances of those
issues.

Change-Id: I357dffdfcb2b405e280a962d366ee65eebf0a8d1
Implements: blueprint migrate-to-ansible-2-2-0

This patch adds the ansible role to deploy the prometheus service which
can be used to collect performance metrics accross the environment

Partially-Implements: blueprint prometheus
Change-Id: I908b9c9dad63ab5c9b80be1e3a80a4fc8191cb9e