a.  安装docker  Prometheus  Grafana Jaeger Elastic Stack

b.  创建简单ballerian 服务

c.  监控ballerina 服务（--observe 选项，启动之后，默认会使用使用http endpoint 发送监控指标，同时也可以使用配置文件 ballerian.conf 配置

      ballerina run --config <path-to-conf>/ballerina.conf ballerinaservice

d.  发送一些请求  http://localhost:9090/hello/sayHello

e.  通过dashboard 查看指标信息

Jaeger via http://localhost:16686/

Grafana dashboard on http://localhost:3000/

Kibana via http://localhost:5601

import ballerina/http;

import ballerina/log;

service<http:Service> hello bind { port:9090 } {

    sayHello (endpoint caller, http:Request req) {

        log:printInfo("This is a test Info log");

        log:printError("This is a test Error log");

        log:printWarn("This is a test Warn log");

        http:Response res = new;

        res.setPayload("Hello, World!");

        _ = caller -> respond(res);

    }

}