Url Image Count Service

This repo contains working code for a Url Image Count service (SpringBoot with Java8).

There are two different implementations provided in this application.

Implementation I (for Live Urls)

• In this implementation the application provides a REST API (/v1/imagecount) that will accept a list of live URLs as JSON input. This call would return a Job Id immediately after invoked.
• The application’s back-end would then get the html contents for each URL and then count the total number of images found in that content by parsing the <img src="" > tag using regular expression. This would be done asynchronously.
• The application also provides another REST API (v1/imagecount/jobId/{jobId}) with a Job ID as path parameter.
  • This API will return a JSON response with the number of images found in the contents of each URL supplied for that job id.
  • The total image count for each url content will be displayed if that particular url request is completed
  • Otherwise the status 'Pending' will be displayed
• The urls in the request payload could be any live urls.
• This implementation uses Executor interface for multithreading and CompletableFuture for asynchronous programming for processing the urls, parsing and counting the images.

Implementation II (for Demo Urls)

• This implementation provides the REST endpoint (/v1/imagecount/demourl) that will accept a list of demo urls as JSON input. This call would also return a Job Id immediately after invoked.
• For the purpose of demonstration this application also contains REST API for providing the demo Url contents. The contents available thro' the uri's '/v1/url1/image, /v1/url2/image and /v1/url3/image'. The response of these urls are not html contents. They are JSON response with tags.
• The same REST endpoint (v1/imagecount/jobId/{jobId}) with a Job ID as path parameter can be used to retrieve the job details.
  • This will also return a JSON response with the number of images found in the contents of each URL supplied for that job id.
  • The total image count for each url content will be displayed if that particular url request is completed
  • Otherwise the status 'Pending' will be displayed
• The urls in the request payload could be any of the three demo (url1, url2, url3) urls.
• This one uses @Async of Spring for url processing and the image count.

Project Features

• Multithreaded & Asynchronous Spring Boot and Java 8 based REST implementation
• Layered approach
• Dependency Injection using Spring
• Input data and Service validation
• Testing
  • Unit Testing
  • Curl
  • Postman

Technology Stack

Description	Tool/Framework
Java version	JDK 1.8
JAX-RS Implementation	Spring Boot
IDE	IntelliJ IDEA 14
Build tool	Gradle
Platform	iOS

Application Design

UrlImageCount Service Resources

Resource Type	Resource URI	HTTP Method
Create a Job (for Live Urls)	/v1/imagecount	POST
Create a Job (for Demo Urls)	/v1/imagecount/demourl	POST
Get a Job Detail	/v1/imagecount/jobId/{jobId}	GET
Get Url1 content	/v1/url1/image	GET
Get Url2 content	/v1/url2/image	GET
Get Url3 content	/v1/url3/image	GET

Project Setup

Service Setup

• Clone/fork this Repo and open/import this Project into IntelliJ or Eclipse
• Open a Terminal window and go to the project directory, 'url-imagecount-service'
• Build/Package the project using 'gradle build' command (use gradle build -x test to skip the test)
• Start SpringBoot application using 'java -jar build/libs/imagecount-service-0.1.0.jar' command
• Test the server by http://localhost:8080/v1/imagecount/jobId/1. This may display {"errorMessage":"JobId 1 is not found"}, as you have not created any Job already.
• For a quick deployment you can use the shared imagecount-service-0.1.0.jar file, in case you didn't have time or ran into any issues.
  • Simply go to the root folder and run the command 'java -jar build/libs/imagecount-service-0.1.0.jar'

How to Consume/Test the Resources

There are 2 ways you can consume these resources. They are by using Postman, and Curl command.

Using Postman

The resources can be consumed by using below Postman collection

• https://www.getpostman.com/collections/856315de6d32166e268f

For Live Urls

Create A Job for Live Url Image Count processing

Retrive A Job Detail which is Pending for some Live Url

Retrive A Job Detail which is fully completed for Live Url

For Demo Urls

Create A Job for Demo Url Image Count processing

Retrive A Job Detail which is Pending for some Demo Url

Retrive A Job Detail which is fully completed for Demo Url

Demo Service Urls

Retrieve Url1 content

Retrieve Url2 content

Retrieve Url3 content

Validation

Retrieve Job Detail - Invalid Job Id

If the JobId is not available then an error message will be displayed

{
    "errorMessage": "JobId 11 is not found"
}

Using Curl command

We can test the resources using below Curl command. The data files are available in the root folder [liveurl_requestX.json or demourl_requestX.json]

Please make sure that the Application is running before running this command.

Create a Job (HTTP POST call)

• Command: You can try with different data file (demourl_request2.json, demourl_request3.json)

  curl -H "Content-Type:application/json" -X POST -d @demourl_request1.json http://localhost:8080/v1/imagecount/demourl
  

• response

  {
          "jobId":"2",
          "imageCountUrls":[
                {
                  "url":"http://localhost:8080/v1/url1/image",
                  "imageCount":"Pending"
                },
                {
                  "url":"http://localhost:8080/v1/url2/image",
                  "imageCount":"Pending"
                }
            ],
            "_links":{
                "self":{
                    "href":"http://localhost:8080/v1/imagecount"
                 },
                 "get":{
                    "href":"http://localhost:8080/v1/imagecount/jobId/2"
                  },
                 "update":{
                    "href":"http://localhost:8080/v1/imagecount/jobId/2"
                  },
                 "delete":{
                    "href":"http://localhost:8080/v1/imagecount/jobId/2"
                  }
              }
          }
  

Retrieve a Job (HTTP GET call)

• Command: curl -H "Content-Type:application/json" -X GET http://localhost:8080/v1/imagecount/jobId/1
• Response

  {
  "jobId": "1",
  "imageCountUrls": [
    {
      "url": "http://localhost:8080/v1/url1/image",
      "imageCount": "60"
    },
    {
      "url": "http://localhost:8080/v1/url2/image",
      "imageCount": "130"
    }
  ],
  "_links": {
    "self": {
      "href": "http://localhost:8080/v1/imagecount/jobId/1"
    },
    "update": {
      "href": "http://localhost:8080/v1/imagecount/jobId/1"
    },
    "delete": {
      "href": "http://localhost:8080/v1/imagecount/jobId/1"
    }
  }
  

Unit Tests

The unit tests are added mainly for Controller, and Service layers. These tests will be run as part of the 'gradle build' command