Spring Boot : Count Page Views - Actuators

Question

I have a requirement to count the views on each endpoint. The idea is to create one common Request Count Mapping for all endpoints which should return the view count based on a dynamically entred endpoint.

Let's say someone wants to check the view counts on http://localhost:8080/user/101 .

1. RequestMappping path = /admin/count & RequestParam = url (Here /user/101)
2. Then create the dynamic Request based on RequestParam http://localhost:8080/actuator/metrics/http.server.requests?tag=uri:/user/101
3. Get and Return the Response of dynamic Request (JSON Object) and get the value of COUNT

I stuck on how to send a dynamic request to http://localhost:8080/actuator/metrics/http.server.requests?tag=uri:/user/101 and return the response of it and get the count value

---

@RequestMapping(path="/admin/count",method=RequestMethod.POST)
public JSONObject count(@RequestParam(name="url") final String url)//@PathVariable(name="url") final String url
{   
    String finalURL = "http://localhost:8080/actuator/metrics/http.server.requests?tag=uri:" + url + "";
    return sendRequestToURL(finalURL);  
}

---

@RequestMapping(path="/{finalURL}",method=RequestMethod.GET)
public JSONObject sendRequestToURL(@PathVariable("finalURL") String url)
{
    //How to return the response Here
}

---

This is what I get when Directly fire the URL

GET: http://localhost:8080/actuator/metrics/http.server.requests?tag=uri:/user/101

  {
    "name": "http.server.requests",
    "description": null,
    "baseUnit": "seconds",
    "measurements": [
        {
            "statistic": "COUNT",
            "value": 1
        },
        {
            "statistic": "TOTAL_TIME",
            "value": 0.3229436
        },
        {
            "statistic": "MAX",
            "value": 0.3229436
        }
    ],
    "availableTags": [
        {
            "tag": "exception",
            "values": [
                "None"
            ]
        },
        {
            "tag": "method",
            "values": [
                "GET"
            ]
        },
        {
            "tag": "outcome",
            "values": [
                "SUCCESS"
            ]
        },
        {
            "tag": "status",
            "values": [
                "200"
            ]
        }
    ]
}

---

Environment:

    `spring boot 2.1.2.RELEASE`
    <java.version>1.8</java.version>

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>

Answer 1

So you want to encapsulate actuator/metrics with /admin/count

There are many ways and library for calling Rest API in Java

I will add the simplest one

Something like this

public JSONObject sendRequestToURL(@PathVariable("finalURL") String urlToRead)
{
      StringBuilder result = new StringBuilder();
      URL url = new URL(urlToRead);
      HttpURLConnection conn = (HttpURLConnection) url.openConnection();
      conn.setRequestMethod("GET");
      BufferedReader rd = new BufferedReader(new InputStreamReader(conn.getInputStream()));
      String line;
      while ((line = rd.readLine()) != null) {
         result.append(line);
      }
      rd.close();
      return new JSONObject(result.toString());  // org.json
}

Edit 1:

You are almost there. Just need to parse String to JSONObject. Try this maybe

String strJson = result.toString().replace("\\\"","'");
JSONObject jo = new JSONObject(strJson.substring(1,json.length()-1));
return jo;

Edit 2:

I guess you have Spring Security in place.

And when you are calling an API internally, Spring is treating as an external call which requires Authentication.

As a workaround, you can exclude /actuator API from security context.

@Override
protected void configure(HttpSecurity http) throws Exception {
    http.csrf().disable().authorizeRequests()
     .antMatchers("/actuator*").permitAll()

     ...
}

or in XML

<security:http  auto-config="true"  use-expressions="true"   >
    <security:intercept-url pattern="/actuator*" access="permitAll"/>

    ...
</security:http>

And hopefully Spring security will ignore this URL and you will not get Login Form.

Answer 2

The idea is you will get the endPoint from user to display to show the view counts which will be done using @RequestParam. Based on the request endPoint create the URLtoMap according to your requirements

(ie methods, status, outcome, exception etc, eg http://localhost:8080/actuator/metrics/http.server.requests?tag=uri:/user/101&tag=method:GET).

---

@RequestMapping(path="/admin/count",method=RequestMethod.POST)
    public int count(@RequestParam(name="endPoint") final String endPoint) throws IOException, JSONException
    {
        final String URLtoMap = "http://localhost:8080/actuator/metrics/http.server.requests?tag=uri:" + endPoint + "";
        return sendRequestToURL(URLtoMap);
    }

---

Now Based on the URLtoMap send Request using HttpURLConnection and get the output using BufferedReader . As I am using Spring Security I was redirected to Login Page. To solve the problem I have added antMatchers in SecurityConfig file as below. If you facing JSONException: Value of type java.lang.String cannot be converted to JSONObject then refer this

public int sendRequestToURL(@PathVariable("URLtoMap") String URLtoMap) throws IOException, JSONException
{
      int count = 0;
      StringBuilder result = new StringBuilder();
      URL url = new URL(URLtoMap);
      HttpURLConnection conn = (HttpURLConnection) url.openConnection();
      conn.setRequestMethod("GET");
      BufferedReader rd = new BufferedReader(new InputStreamReader(conn.getInputStream()));
      String line;
      while ((line = rd.readLine()) != null) {
         result.append(line);
      }
      rd.close();

      try {
            JSONObject jsonObject =new JSONObject(result.toString().replace("\"", "")); 
            JSONObject jsonCountObject = new JSONObject(jsonObject.getJSONArray("measurements").get(0).toString());
            count =(int) jsonCountObject.get("value");
        }
        catch (JSONException e) {
            e.printStackTrace();
        }

      return count;
}

---

SecurityConfig

@Override
        protected void configure(HttpSecurity http) throws Exception{

             http
             .csrf().disable()
             .authorizeRequests().antMatchers("/login").permitAll()
             .antMatchers(HttpMethod.GET,"/actuator/**").permitAll() 
             .antMatchers(HttpMethod.POST,"/actuator/**").permitAll() 
}

pom.xml

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-core</artifactId>
</dependency>

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
</dependency>

<dependency>
  <groupId>org.json</groupId>
  <artifactId>json</artifactId>
  <version>20090211</version>
</dependency>

Import the Correct Packages

import org.json.JSONException;
import org.json.JSONObject;
import java.net.URL;
import java.net.HttpURLConnection;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;