docs: add docs for `taoskeeper with prometheus` (#21052)

docs/en/14-reference/14-taosKeeper.md

@@ -223,3 +223,29 @@ Content-Length: 19
 
 {"version":"1.0.0"}
 ```
+
+### taoskeeper with Prometheus
+
+There is `/metrics` api in taoskeeper provide TDengine metric data for Prometheus. 
+
+#### scrape config
+
+Scrape config in Prometheus specifies a set of targets and parameters describing how to scrape metric data from endpoint. For more information, please reference to [Prometheus documents](https://prometheus.io/docs/prometheus/latest/configuration/configuration/#scrape_config).
+
+```
+# A scrape configuration containing exactly one endpoint to scrape:
+# Here it's Prometheus itself.
+scrape_configs:
+  - job_name: "taoskeeper"
+    # metrics_path defaults to '/metrics'
+    # scheme defaults to 'http'.
+    static_configs:
+      - targets: ["localhost:6043"]
+```
+
+#### Dashboard
+
+There is a dashboard named `TaosKeeper Prometheus Dashboard for 3.x`, which provides a monitoring dashboard similar to TInsight.
+
+In Grafana, click the Dashboard menu and click `import`, enter the dashboard ID `18587` and click the `Load` button. Then finished importing `TaosKeeper Prometheus Dashboard for 3.x` dashboard.
+

docs/zh/14-reference/14-taosKeeper.md

@@ -226,3 +226,29 @@ Content-Length: 19
 
 {"version":"1.0.0"}
 ```
+
+### 集成 Prometheus
+
+taoskeeper 提供了 `/metrics` 接口，返回了 Prometheus 格式的监控数据，Prometheus 可以从 taoskeeper 抽取监控数据，实现通过 Prometheus 监控 TDengine 的目的。
+
+#### 抽取配置
+
+Prometheus 提供了 `scrape_configs` 配置如何从 endpoint 抽取监控数据，通常只需要修改 `static_configs` 中的 targets 配置为 taoskeeper 的 endpoint 地址，更多配置信息请参考 [Prometheus 配置文档](https://prometheus.io/docs/prometheus/latest/configuration/configuration/#scrape_config)。
+
+```
+# A scrape configuration containing exactly one endpoint to scrape:
+# Here it's Prometheus itself.
+scrape_configs:
+  - job_name: "taoskeeper"
+    # metrics_path defaults to '/metrics'
+    # scheme defaults to 'http'.
+    static_configs:
+      - targets: ["localhost:6043"]
+```
+
+#### Dashboard
+
+我们提供了 `TaosKeeper Prometheus Dashboard for 3.x` dashboard，提供了和 TDinsight 类似的监控 dashboard。
+
+在 Grafana Dashboard 菜单点击 `import`，dashboard ID 填写 `18587`，点击 `Load` 按钮即可导入 `TaosKeeper Prometheus Dashboard for 3.x` dashboard。
+