This patch forces Helm to abort if kubernetes.clusterName is not set
when *.fluentbit.enabled = true.

Moreover, if Prometheus remote write is enabled and
`metrics.prometheus.server.remoteWrite.username` and
`metrics.prometheus.server.remoteWrite.password` are not set the chart
will fail to install now.

With this patch the chart will fail to install if either tenant.name
or tenant.password are not set if they're necessary, example:

```
λ helm -n monitoring diff upgrade kubernetes-monitoring . -f values.yaml -f ibarrien.yaml
Error: Failed to render chart: exit status 1: Error: execution error at (cern-it-monitoring-kubernetes/templates/fluentbit-metrics/configmap.yaml:22:13): Tenand password is required
```

If no fluentbit forwarding is configured, i.e.:

```yaml
metrics:
  fluentbit:
    enabled: false

logs:
  fluentbit:
    enabled: false
```

then the chart installs fine as they're note required in that case.

This should prevent the following from happening in the MONIT clusters
that push metrics directly from Prometheus to MoM without any
Fluentbit in between:

ts=2025-02-14T11:37:32.111Z caller=dedupe.go:112 component=remote
level=warn remote_name=6c01d0
url=http://it-monit-metrics-fluentbit:8080/api/prom/push msg="Failed
to send batch, retrying" err="Post
\"http://it-monit-metrics-fluentbit:8080/api/prom/push\": dial tcp:
lookup it-monit-metrics-fluentbit on 10.254.0.10:53: no such host"

In commit c6c3db28 we added support for lua scripts provided via user
values.

This commit adds a default value and documents this in the values file.

Reported-at: https://its.cern.ch/jira/browse/MONIT-4106


Signed-off-by: Guillermo Facundo Colunga <guillermo.facundo.colunga@gmail.com>
Signed-off-by: Guillermo Facundo Colunga <guillermo.facundo.colunga@cern.ch>

While doing trying to mimic the OpenShift logging setup with the current
Helm chart we noticed that they were using the lua scripts input from
the fluent bit official Helm chart. In our case this was not possible
and had to be done by adding secrets one by one.

We agreed to mimic this behaviour and had our own helm chart have the
option to add lua scripts to the fluent bit via helm chart values.

This commit modifies the configmap used to create the lua script that
we required for the timestampt in such a way that now it creates this
first lua script but also creates any other provided by the users via
the values of the helm chart.

Reported-at: https://its.cern.ch/jira/browse/MONIT-4106


Signed-off-by: Guillermo Facundo Colunga <guillermo.facundo.colunga@gmail.com>
Signed-off-by: Guillermo Facundo Colunga <guillermo.facundo.colunga@cern.ch>

In commit 8c054c8 we added support for lua scripts provided via user
values.

This commit adds a default value and documents this in the values file.

Reported-at: https://its.cern.ch/jira/browse/MONIT-4106


Signed-off-by: Guillermo Facundo Colunga <guillermo.facundo.colunga@gmail.com>
Signed-off-by: Guillermo Facundo Colunga <guillermo.facundo.colunga@cern.ch>

While doing trying to mimic the OpenShift logging setup with the current
Helm chart we noticed that they were using the lua scripts input from
the fluent bit official Helm chart. In our case this was not possible
and had to be done by adding secrets one by one.

We agreed to mimic this behaviour and had our own helm chart have the
option to add lua scripts to the fluent bit via helm chart values.

This commit modifies the configmap used to create the lua script that
we required for the timestampt in such a way that now it creates this
first lua script but also creates any other provided by the users via
the values of the helm chart.

Reported-at: https://its.cern.ch/jira/browse/MONIT-4106


Signed-off-by: Guillermo Facundo Colunga <guillermo.facundo.colunga@gmail.com>
Signed-off-by: Guillermo Facundo Colunga <guillermo.facundo.colunga@cern.ch>

In commit 2d80829 we added the support for custom prometheus server
relabelings.

This commit adds the default value for this option into the values.yaml
file.

Reported-at: https://its.cern.ch/jira/browse/MONIT-4105


Signed-off-by: Guillermo Facundo Colunga <guillermo.facundo.colunga@gmail.com>
Signed-off-by: Guillermo Facundo Colunga <guillermo.facundo.colunga@cern.ch>

As reported by some users it would be very interesting for them to be
able to filter out metrics or transform them. Not all of them are
interested in keeping all the metrics that come by default with the
chart. Also they would like sometimes to rename some of the metrics or
labels that came out of the box.

Given prometheus architecture this should have been done on each target
scrape policy. Instead, given our current set up this can be centralised
in the remote write to the local fluent bit, applying the transformation
just before we push the metrics to the fluentbit and this fluentbit to
the monitoring infrastructure.

This commit modifies the prometheus server template in such a way that
if the user adds some custom relablings in the values they are appended
under the normal relabelings that are applied to every installation.
If no config is provided then nothing is modified.

Reported-at: https://its.cern.ch/jira/browse/MONIT-4105


Signed-off-by: Guillermo Facundo Colunga <guillermo.facundo.colunga@gmail.com>
Signed-off-by: Guillermo Facundo Colunga <guillermo.facundo.colunga@cern.ch>