vmalert: support configuration file for notifiers
* vmalert notifiers now can be configured via file
see https://docs.victoriametrics.com/vmalert.html#notifier-configuration-file
* add support of Consul service discovery for notifiers config
see https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1947
* add UI section for currently loaded/discovered notifiers
* deprecate `-rule.configCheckInterval` in favour of `-configCheckInterval`
* add ability to suppress logs for duplicated targets for notifiers discovery
* change behaviour of `vmalert_alerts_send_errors_total` - it now accounts
for failed alerts, not HTTP calls.
For a long time notifier.Addr flag was required. The assumption was that vmalert will
be always used for alerting. However, practice shows that some users need only
recording rules. In this case, requirement of notifier.Addr is ambigious.
The change verifies if loaded config contains recording or alerting rules and
if there are corresponding flags set. This is true for initial config load
and hot reload.
Signed-off-by: hagen1778 <roman@victoriametrics.com>
Regression was introduced during code refactoring. It potentially
could lead to situation when SIGHUP signals were ignored while
vmalert was still busy with initing group manager.
Signed-off-by: hagen1778 <roman@victoriametrics.com>
* vmalert: add flag to limit the max value for auto-resovle duration for alerts
The new flag `rule.maxResolveDuration` suppose to limit max value for
alert.End param, which is used by notifiers like Alertmanager for alerts auto resolve.
https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1586
New flag `-rule.configCheckInterval` defines how often `vmalert` will re-read
config file. If it detects any changes, the config will be reloaded.
This behaviour is turned off by default.
https://github.com/VictoriaMetrics/VictoriaMetrics/issues/512
The change adds no new functionality and aims to move flags definitions
to subpackages that are using them. This should improve readability
of the main function.
app/vmalert: add support for TLS configuration
Add support for TLS optional configuration in a similar fashion to what
is currently supported in other vmutils such as vmagent. TLS
configuration options are distinct for datasource, remoteRead,
remoteWrite as well as notifier.
app/vmalert: Support custom URL for alerts source
Add flag `external.alert.source` for configuring custom URL
for alert's source. This may be handy to re-point default source
URL to other systems like Grafana.
Updates #517
