Loki ERROR log告警

实现loki 采集error日志，出现error 日志，告警。

1.修改Loki配置文件
在loki-local-config.yml中添加Alertmanager的配置，包括告警规则存储路径、Alertmanager的URL等。例如：
ruler:
enable_api: true
enable_alertmanager_v2: true
alertmanager_refresh_interval: 3m0s
alertmanager_url: http://xxxx:8893
storage:
type: local
local:
directory: /usr/local/monitlog/loki-rules

2.新建规则文件夹
/usr/local/monitlog/loki-rules/fake/loki_first_rules.yml

mkdir /usr/local/monitlog/loki-rules && mkdir /usr/local/monitlog/loki-rules/fake && cd /usr/local/monitlog/loki-rules/fake

vim loki_ck_rules.yml

groups:
- name: error-logs-group
  rules:
  - alert: error-logs-alert
    expr: count_over_time({filename="/tmp/app_log/my/bbc-gateway_error.log" } |="app_invoke_url_error" !=":255" [3m])  > 1
    for: 3m
    labels:
      severity: error
      env: prod
      countryCode: my
    annotations:
      summary: "my最近3分钟logError异常{{ $labels }}"
      description: "数量：{{ $value }}"