feat(mo-ob): support k8s events observability (#21)

## What type of PR is this?

* [x] Feature
* [ ] BUG
* [ ] Alerts
* [ ] Improvement
* [ ] Documentation
* [ ] Test and CI

## Which issue(s) this PR related:

issue # https://github.com/matrixorigin/MO-Cloud/issues/1638

## What this PR does / why we need it:

1. 添加 grafana alloy 作为 mo-ob-opensource 的子chart部署
2. grafana alloy values 默认配置采集全部 namespace 的 event 并发送到 loki

Author: EZ4BRUCE

README.md

@@ -139,6 +139,20 @@ kubectl get secret -n ${OBNS} grafana-admin-secret  -o jsonpath="{.data['admin-p
 # 进阶配置
 
 
+## 需要替换的镜像源
+
+如果部署的时候发现 image pull failed 等错误，需要替换镜像源（如阿里云），这些被替换的镜像都已经显示的写在了 chart 的 values.yaml 下，如 `charts/mo-ob-opensource/values.yaml` 下
+
+```
+alloy:
+  image:
+    registry: "docker.io"
+    repository: grafana/alloy
+    tag: v1.3.1
+```
+将对应的镜像 push 到需要替换的镜像源仓库即可部署
+
+
 ## alertmanger 打开 web 鉴权
 
 1.在 `charts/mo-ruler-stack/values.yaml` 下设置 secretValue.alertmanager，alertmanager_web_auth_password_bcrypted 是 alertmanager_web_auth_password 的 bcrypt 加密

charts/mo-ob-opensource/Chart.yaml

@@ -2,7 +2,7 @@ apiVersion: v2
 name: mo-ob-opensource
 description: mo-ob-opensource's Helm chart for Kubernetes
 type: application
-version: 1.0.4
+version: 1.0.5
 appVersion: 0.9.0
 dependencies:
 - condition: kube-prometheus-stack.enabled
@@ -17,3 +17,7 @@ dependencies:
   name: promtail
   repository: https://grafana.github.io/helm-charts
   version: 6.15.1
+- condition: alloy.enabled
+  name: alloy
+  repository: https://grafana.github.io/helm-charts
+  version: 0.6.1

charts/mo-ob-opensource/values.yaml

@@ -13,6 +13,41 @@ defaultDatasource:
   # cooperate with template templates/loki-datasource.yaml
   loki: true
 
+# alloy for k8s events
+alloy:
+  
+  image:
+    registry: "docker.io"
+    repository: grafana/alloy
+    tag: v1.3.1
+  configReloader:
+    enabled: true
+    image:
+      registry: "ghcr.io"
+      repository: jimmidyson/configmap-reload
+      tag: v0.12.0
+  enabled: true
+  alloy:
+    resources: 
+      limits:
+        cpu: 500m
+        memory: 512Mi
+      requests:
+        cpu: 200m
+        memory: 200Mi
+    configMap:
+      # -- Content to assign to the new ConfigMap.  This is passed into `tpl` allowing for templating from values.
+      content: |
+        loki.source.kubernetes_events "k8s_event" {
+          forward_to = [loki.write.local.receiver]
+        }
+
+        loki.write "local" {
+          endpoint {
+            url = "http://{{ .Release.Name }}-loki-gateway/loki/api/v1/push"
+          }
+        }
+
 promtail:
   enabled: true
   serviceMonitor:
@@ -97,6 +132,15 @@ loki:
     # retention related issue: https://github.com/matrixone-cloud/observability/issues/86
     retention_deletes_enabled: true
     retention_period: 720h
+  lokiCanary:
+    enabled: false
+  
+  chunksCache:
+    enabled: false
+  
+  resultsCache:
+    enabled: false
+  
   loki:
     # -- Defines what kind of object stores the configuration, a ConfigMap or a Secret.
     # In order to move sensitive information (such as credentials) from the ConfigMap/Secret to a more secure location (e.g. vault), it is possible to use [environment variables in the configuration](https://grafana.com/docs/loki/latest/configuration/#use-environment-variables-in-the-configuration).

dev/mo-ob-opensource.dev.yaml

@@ -91,7 +91,7 @@ loki:
         cpu: "2000m"
 
 kube-prometheus-stack:
-  enabled: false
+  enabled: true
   prometheus:
     prometheusSpec:
       resources:

dev/mo-ruler-stack.dev.yaml

@@ -68,7 +68,7 @@ alertmanager:
       - name: "null" 
       - name: 'wecom-group'
         webhook_configs:
-        - url: "http://alertmanager-webhook-adapter/webhook/send?channel_type=weixin&token=ca66171c-cc72-4f88-abd5-c6802df203bd"
+        - url: "http://alertmanager-webhook-adapter/webhook/send?channel_type=weixin&token=<token>"
 
 grafana:
   persistence: