Exposing prometheus via Ingress documentation is incomplete

[jrstarke]

What happened?

When using the example from the Setting Up Ingress in the Exposing via Ingress document, when running
build.sh example.jsonnet, I get

STATIC ERROR: example.jsonnet:55:1: Unknown variable: k

This seems to make sense, because we haven't defined k anywhere. The comment seems to suggest we should be using k8s-libsonnet, but it doesn't appear we're using that anywhere else in the repo

Did you expect to see some different?

I expected it to build the manifests

How to reproduce it (as minimally and precisely as possible):

local kp =
  (import 'kube-prometheus/main.libsonnet') +
  // Uncomment the following imports to enable its patches
  // (import 'kube-prometheus/addons/anti-affinity.libsonnet') +
  // (import 'kube-prometheus/addons/managed-cluster.libsonnet') +
  // (import 'kube-prometheus/addons/node-ports.libsonnet') +
  // (import 'kube-prometheus/addons/static-etcd.libsonnet') +
  // (import 'kube-prometheus/addons/custom-metrics.libsonnet') +
  // (import 'kube-prometheus/addons/external-metrics.libsonnet') +
  // (import 'kube-prometheus/addons/pyrra.libsonnet') +
  {
    values+:: {
      common+: {
        namespace: 'monitoring',
      },
    },
    prometheus+:: {
      prometheus+: {
        spec+: {
          externalUrl: 'https://prometheus.example.com',
        },
      },
    },
    ingress+:: {
      'basic-auth-middleware': {
        apiVersion: 'traefik.containo.us/v1alpha1',
        kind: 'Middleware',
        metadata: {
          name: 'basic-auth',
          namespace: $.prometheus.prometheus.metadata.namespace,
        },
        spec: {
          basicAuth: {
            removeHeader: 'true',
            secret: 'basic-auth-secret',
          },
        },
      },
      'prometheus-k8s': {
        apiVersion: 'networking.k8s.io/v1',
        kind: 'Ingress',
        metadata: {
          name: $.prometheus.prometheus.metadata.name,
          namespace: $.prometheus.prometheus.metadata.namespace,
          annotations: {
            'traefik.ingress.kubernetes.io/router.entrypoints': 'websecure',
            'traefik.ingress.kubernetes.io/router.middlewares': 'monitoring-basic-auth@kubernetescrd'
          },
        },
        spec: {
          rules: [{
            host: 'prometheus.example.com',
            http: {
              paths: [{
                backend: {
                  service: {
                    name: $.prometheus.service.metadata.name,
                    port: 'web',
                  },
                },
              }],
            },
          }],
        },
      },
    },
  };

k.core.v1.list.new([
  kp.ingress['prometheus-k8s'],
  kp.ingress['basic-auth-secret'],
])

{ 'setup/0namespace-namespace': kp.kubePrometheus.namespace } +
{
  ['setup/prometheus-operator-' + name]: kp.prometheusOperator[name]
  for name in std.filter((function(name) name != 'serviceMonitor' && name != 'prometheusRule'), std.objectFields(kp.prometheusOperator))
} +
// { 'setup/pyrra-slo-CustomResourceDefinition': kp.pyrra.crd } +
// serviceMonitor and prometheusRule are separated so that they can be created after the CRDs are ready
{ 'prometheus-operator-serviceMonitor': kp.prometheusOperator.serviceMonitor } +
{ 'prometheus-operator-prometheusRule': kp.prometheusOperator.prometheusRule } +
{ 'kube-prometheus-prometheusRule': kp.kubePrometheus.prometheusRule } +
{ ['alertmanager-' + name]: kp.alertmanager[name] for name in std.objectFields(kp.alertmanager) } +
{ ['blackbox-exporter-' + name]: kp.blackboxExporter[name] for name in std.objectFields(kp.blackboxExporter) } +
{ ['grafana-' + name]: kp.grafana[name] for name in std.objectFields(kp.grafana) } +
// { ['pyrra-' + name]: kp.pyrra[name] for name in std.objectFields(kp.pyrra) if name != 'crd' } +
{ ['kube-state-metrics-' + name]: kp.kubeStateMetrics[name] for name in std.objectFields(kp.kubeStateMetrics) } +
{ ['kubernetes-' + name]: kp.kubernetesControlPlane[name] for name in std.objectFields(kp.kubernetesControlPlane) }
{ ['node-exporter-' + name]: kp.nodeExporter[name] for name in std.objectFields(kp.nodeExporter) } +
{ ['prometheus-' + name]: kp.prometheus[name] for name in std.objectFields(kp.prometheus) } +
{ ['prometheus-adapter-' + name]: kp.prometheusAdapter[name] for name in std.objectFields(kp.prometheusAdapter) } +
{ ['ingress-' + name]: kp.ingress[name] for name in std.objectFields(kp.ingress) }

Environment

Mac Sonoma 14.2.1

• Prometheus Operator version:

  quay.io/prometheus-operator/prometheus-operator:v0.57.0

• Kubernetes version information:

WARNING: This version information is deprecated and will be replaced with the output from kubectl version --short.  Use --output=yaml|json to get the full version.
Client Version: version.Info{Major:"1", Minor:"27", GitVersion:"v1.27.4", GitCommit:"fa3d7990104d7c1f16943a67f11b154b71f6a132", GitTreeState:"clean", BuildDate:"2023-07-19T12:14:48Z", GoVersion:"go1.20.6", Compiler:"gc", Platform:"darwin/arm64"}
Kustomize Version: v5.0.1
Server Version: version.Info{Major:"1", Minor:"23", GitVersion:"v1.23.3+k3s1", GitCommit:"5fb370e53e0014dc96183b8ecb2c25a61e891e76", GitTreeState:"clean", BuildDate:"2022-01-27T02:14:38Z", GoVersion:"go1.17.5", Compiler:"gc", Platform:"linux/arm64"}
WARNING: version difference between client (1.27) and server (1.23) exceeds the supported minor version skew of +/-1    

<!-- Replace the command with its output above -->

• Kubernetes cluster kind:

k3s-ansible

• Manifests:

insert manifests relevant to the issue

• Prometheus Operator Logs:

Insert Prometheus Operator logs relevant to the issue here

• Prometheus Logs:

Insert Prometheus logs relevant to the issue here

Anything else we need to know?:

[jrstarke]

I'm not sure what the intent of the list was

k.core.v1.list.new([
  kp.ingress['prometheus-k8s'],
  kp.ingress['basic-auth-secret'],
])

But by dropping it, everything worked as expected.