Integade alertManager for Monitoring

 - Added kubenetes manisfest for alert manger
 - config file from config/prmetheus

cluster/terraform_kubernetes/alertmanager.tf

@@ -0,0 +1,165 @@
+data "azurerm_key_vault" "key_vault_slack" {
+  name                = var.cluster_kv
+  resource_group_name = var.resource_group_name
+}
+data "azurerm_key_vault_secret" "slack_secret" {
+  key_vault_id = data.azurerm_key_vault.key_vault_slack.id
+  name         = "SLACK-SECRET"
+}
+
+locals {
+  alertmanager_config_path = "${path.module}/config/prometheus/alertmanager-config.yaml"
+  alertmanager_config_content = templatefile(local.alertmanager_config_path, {
+    slack_secret  = data.azurerm_key_vault_secret.slack_secret.value,
+    slack_channel = var.slack_channel
+  })
+
+  template_files = {
+    "default.tmpl" = "${path.module}/config/prometheus/alertmanager-default.yaml",
+    "slack.tmpl"   = "${path.module}/config/prometheus/alertmanager-slack.yaml"
+  }
+
+  alertmanager_templates = { for k, v in local.template_files : k => file(v) }
+}
+
+resource "kubernetes_manifest" "configmap_monitoring_alertmanager_config" {
+  manifest = {
+    apiVersion = "v1"
+    kind       = "ConfigMap"
+    metadata = {
+      name      = "alertmanager-config"
+      namespace = var.namespace
+    }
+    data = {
+      "config.yml" = local.alertmanager_config_content
+    }
+  }
+}
+
+resource "kubernetes_manifest" "configmap_monitoring_alertmanager_templates" {
+  manifest = {
+    apiVersion = "v1"
+    kind       = "ConfigMap"
+    metadata = {
+      name      = "alertmanager-templates"
+      namespace = var.namespace
+    }
+    data = local.alertmanager_templates
+  }
+}
+
+# Deployment for AlertManager
+resource "kubernetes_manifest" "deployment_monitoring_alertmanager" {
+  manifest = {
+    "apiVersion" = "apps/v1"
+    "kind"       = "Deployment"
+    "metadata" = {
+      "name"      = "alertmanager"
+      "namespace" = var.namespace
+    }
+    "spec" = {
+      "replicas" = 1
+      "selector" = {
+        "matchLabels" = {
+          "app" = "alertmanager"
+        }
+      }
+      "template" = {
+        "metadata" = {
+          "labels" = {
+            "app" = "alertmanager"
+          }
+        }
+        "spec" = {
+          "containers" = [
+            {
+              "args" = [
+                "--config.file=/etc/alertmanager/config.yml",
+                "--storage.path=/alertmanager",
+              ]
+              "image" = "prom/alertmanager:${var.alertmanager_image_version}"
+              "name"  = "alertmanager"
+              "ports" = [
+                {
+                  "containerPort" = 9093
+                  "name"          = "alertmanager"
+                },
+              ]
+              "resources" = {
+                "limits" = {
+                  "cpu"    = var.alertmanager_cpu_limit
+                  "memory" = var.alertmanager_memory_limit
+                }
+                "requests" = {
+                  "cpu"    = var.alertmanager_cpu_request
+                  "memory" = var.alertmanager_memory_request
+                }
+              }
+              "volumeMounts" = [
+                {
+                  "mountPath" = "/etc/alertmanager"
+                  "name"      = "config-volume"
+                },
+                {
+                  "mountPath" = "/etc/alertmanager-templates"
+                  "name"      = "templates-volume"
+                },
+                {
+                  "mountPath" = "/alertmanager"
+                  "name"      = "alertmanager"
+                },
+              ]
+            },
+          ]
+          "volumes" = [
+            {
+              "configMap" = {
+                "name" = "alertmanager-config"
+              }
+              "name" = "config-volume"
+            },
+            {
+              "configMap" = {
+                "name" = "alertmanager-templates"
+              }
+              "name" = "templates-volume"
+            },
+            {
+              "emptyDir" = {}
+              "name"     = "alertmanager"
+            },
+          ]
+        }
+      }
+    }
+  }
+}
+
+# Service for AlertManager
+resource "kubernetes_manifest" "service_monitoring_alertmanager" {
+  manifest = {
+    "apiVersion" = "v1"
+    "kind"       = "Service"
+    "metadata" = {
+      "annotations" = {
+        "prometheus.io/port"   = "9093"
+        "prometheus.io/scrape" = "true"
+      }
+      "name"      = "alertmanager"
+      "namespace" = var.namespace
+    }
+    "spec" = {
+      "ports" = [
+        {
+          "nodePort"   = 31000
+          "port"       = 9093
+          "targetPort" = 9093
+        },
+      ]
+      "selector" = {
+        "app" = "alertmanager"
+      }
+      "type" = "NodePort"
+    }
+  }
+}

cluster/terraform_kubernetes/config/prometheus/alertmanager-config.yaml

@@ -0,0 +1,21 @@
+global:
+templates:
+  - '/etc/alertmanager/*.tmpl'
+route:
+  receiver: alert-default
+  group_by: ['alertname', 'priority']
+  group_wait: 10s
+  repeat_interval: 30m
+  routes:
+    - receiver: slack_demo
+      match:
+        severity: slack
+      group_wait: 10s
+      repeat_interval: 1m
+receivers:
+- name: alert-default
+- name: slack_demo
+  slack_configs:
+  - api_url: '${slack_secret}'
+    channel: '${slack_channel}'
+    send_resolved: true