feat: deploy lightweight observability stack via Ansible

ansible/roles/observability/defaults/main.yml

@@ -0,0 +1,16 @@
+---
+observability_namespace: "observability"
+
+prometheus_chart_version: "68.4.4"
+loki_chart_version: "6.24.0"
+promtail_chart_version: "6.16.6"
+
+grafana_admin_password: ""
+
+prometheus_storage_size: "10Gi"
+grafana_storage_size: "5Gi"
+loki_storage_size: "10Gi"
+
+prometheus_storage_class: "local-path"
+grafana_storage_class: "local-path"
+loki_storage_class: "local-path"

ansible/roles/observability/tasks/main.yml

@@ -0,0 +1,166 @@
+---
+- name: Check if Helm is installed
+  command: helm version --short
+  register: helm_check
+  changed_when: false
+  failed_when: false
+
+- name: Install Helm
+  shell: curl -fsSL https://raw.githubusercontent.com/helm/helm/main/scripts/get-helm-3 | bash
+  when: helm_check.rc != 0
+  changed_when: true
+
+- name: Ensure observability namespace exists
+  command: kubectl create namespace {{ observability_namespace }}
+  register: create_observability_ns
+  failed_when: create_observability_ns.rc != 0 and "AlreadyExists" not in create_observability_ns.stderr
+  changed_when: create_observability_ns.rc == 0
+
+- name: Set Grafana admin password
+  set_fact:
+    grafana_password_effective: "{{ grafana_admin_password if grafana_admin_password | length > 0 else lookup('password', '/dev/null length=32 chars=ascii_letters,digits') }}"
+
+- name: Write kube-prometheus-stack values
+  copy:
+    dest: /tmp/kube-prometheus-stack-values.yaml
+    mode: "0644"
+    content: |
+      grafana:
+        enabled: true
+        adminPassword: {{ grafana_password_effective }}
+        persistence:
+          enabled: true
+          storageClassName: {{ grafana_storage_class }}
+          size: {{ grafana_storage_size }}
+        service:
+          type: ClusterIP
+      prometheus:
+        prometheusSpec:
+          retention: 7d
+          storageSpec:
+            volumeClaimTemplate:
+              spec:
+                storageClassName: {{ prometheus_storage_class }}
+                accessModes: ["ReadWriteOnce"]
+                resources:
+                  requests:
+                    storage: {{ prometheus_storage_size }}
+      alertmanager:
+        enabled: false
+      kubeEtcd:
+        enabled: false
+      kubeControllerManager:
+        enabled: false
+      kubeScheduler:
+        enabled: false
+
+- name: Add Prometheus Helm repo
+  command: helm repo add prometheus-community https://prometheus-community.github.io/helm-charts
+  register: add_prom_repo
+  failed_when: add_prom_repo.rc != 0 and "already exists" not in add_prom_repo.stderr
+  changed_when: add_prom_repo.rc == 0
+
+- name: Add Grafana Helm repo
+  command: helm repo add grafana https://grafana.github.io/helm-charts
+  register: add_grafana_repo
+  failed_when: add_grafana_repo.rc != 0 and "already exists" not in add_grafana_repo.stderr
+  changed_when: add_grafana_repo.rc == 0
+
+- name: Update Helm repos
+  command: helm repo update
+  changed_when: false
+
+- name: Install kube-prometheus-stack
+  command: >-
+    helm upgrade --install kube-prometheus-stack prometheus-community/kube-prometheus-stack
+    --namespace {{ observability_namespace }}
+    --version {{ prometheus_chart_version }}
+    --values /tmp/kube-prometheus-stack-values.yaml
+    --wait
+    --timeout 10m
+  changed_when: true
+
+- name: Write Loki values
+  copy:
+    dest: /tmp/loki-values.yaml
+    mode: "0644"
+    content: |
+      loki:
+        auth_enabled: false
+        commonConfig:
+          replication_factor: 1
+        storage:
+          type: filesystem
+      singleBinary:
+        replicas: 1
+        persistence:
+          enabled: true
+          storageClass: {{ loki_storage_class }}
+          size: {{ loki_storage_size }}
+      test:
+        enabled: false
+      monitoring:
+        selfMonitoring:
+          enabled: false
+        lokiCanary:
+          enabled: false
+
+- name: Install Loki
+  command: >-
+    helm upgrade --install loki grafana/loki
+    --namespace {{ observability_namespace }}
+    --version {{ loki_chart_version }}
+    --values /tmp/loki-values.yaml
+    --wait
+    --timeout 10m
+  changed_when: true
+
+- name: Write Promtail values
+  copy:
+    dest: /tmp/promtail-values.yaml
+    mode: "0644"
+    content: |
+      config:
+        clients:
+          - url: http://loki-gateway.{{ observability_namespace }}.svc.cluster.local/loki/api/v1/push
+
+- name: Install Promtail
+  command: >-
+    helm upgrade --install promtail grafana/promtail
+    --namespace {{ observability_namespace }}
+    --version {{ promtail_chart_version }}
+    --values /tmp/promtail-values.yaml
+    --wait
+    --timeout 10m
+  changed_when: true
+
+- name: Create Grafana Loki datasource
+  command: kubectl apply -f -
+  args:
+    stdin: |
+      apiVersion: v1
+      kind: ConfigMap
+      metadata:
+        name: grafana-datasource-loki
+        namespace: {{ observability_namespace }}
+        labels:
+          grafana_datasource: "1"
+      data:
+        loki-datasource.yaml: |
+          apiVersion: 1
+          datasources:
+            - name: Loki
+              type: loki
+              access: proxy
+              url: http://loki-gateway.{{ observability_namespace }}.svc.cluster.local
+              isDefault: false
+  changed_when: true
+
+- name: Show observability access details
+  debug:
+    msg: |
+      Observability stack deployed.
+      Namespace: {{ observability_namespace }}
+      Grafana (tailnet): kubectl -n {{ observability_namespace }} port-forward svc/kube-prometheus-stack-grafana 3000:80
+      Prometheus (tailnet): kubectl -n {{ observability_namespace }} port-forward svc/kube-prometheus-stack-prometheus 9090:9090
+      Grafana admin password: {{ grafana_password_effective }}