S7ack Application

Stack is a question and answer site for all, based on the famous programming Q&A website Stack Overflow. It's built using the MVC pattern on the server side, using Java EE APIs (Servlets, JSPs, JSTL, JDBC), runs on Open Liberty Application server and runs in a Dockerised environment.

Students

Student	GitHub username
Ludovic Bonzon	bonzonlu
Claire Delhomme	Kleeer
Pablo Mercado	pabloheigvd
Vitor Vaz Afonso	vitorva

Prerequisites

Open your installation folder and clone this repository.

Do not forget to edit your /etc/hosts file to add:

127.0.0.1   stack.ch

Pull image and run

You can cd into /scripts folder and run:

./pullAndRun.sh

Open: stack.ch:9080/stack/

Dev

Package and deploy website

Use application authentification key

...such that the application interacts with the gamification engine. Modify in src/main/liberty/config/server.env:

APP_KEY=<your gamification application authentification key>

in the same file, write down the url of the gamification engine at:

BACKEND_URL=<your gamification engine URL>

You can cd into /scripts folder and run:

  ./startDocker.sh

Open: stack.ch:9080/stack/

Testing

End-to-end tests

Using CodeceptJS and Puppeteer.

Prerequisites :

• The application must be running. See run instructions.
• You must have installed the required dependencies by running from project base folder :

  cd codecept
  npm install
  node node_modules/puppeteer/install.js

• For test #12 gamification to succeed, the gamification project must be running as well.

From project base folder, run

  cd codecept
  npx codeceptjs run --steps

All tests can be succesfully run on their own with npx codeceptjs run --steps e2e/<TEST_NAME>.

After testing, you can still consult it at: stack.ch:9080/stack/

The following features have been tested :

• Registration
• Login
• Filter (on pages reserved to logged users)
• Logout
• Question submission
• User profile
• Answer submission
• Comment submission
• Vote submission
• Statistics
• Pagination
• Gamification

Note: You may want to rerun the script since the script assumes you already have downloaded openliberty/open-liberty:kernel-java11-openj9-ubi image. The script waits 30s for the image to be built and launches the server.

JMeter

We have a load test plan you can open at jmeter/stack_test_plan.jmx with JMeter.

Before starting the test, deploy a website by cd'ing into /scripts folder and run:

./pullAndRun.sh

And checkout out the votes at stack.ch:9080/stack/

Application

Pages list

• Homepage and questions' list (/questions)
• User authentication
  • Use login page (/login)
  • User registration page (/register)
  • Profile page (/profile)
• Question details page with answers and comments (/question?uuid=)
• Question submission page (/submitQuestion)
• Statistics page (/Statistics)

User behaviours

Anonymous

An anonymous user can access the homepage ans see the list of questions, with reduced question content, he can click on a question to see its details (full question content, answers to the question and comments to both questions and answers). He can see the global statistics page and obviously can register as a new user to enjoy all the apps' functionalities.

Registered user

Once an anonymous user is registered, he can log in. He has then access to the same elements as an anonymous user and can see a profile page of his user infos, with statistics on how many questions and answers he has given. He can also ask new questions and the most interesting part, he can now reply to existing questions, comment on questions and answers and also vote for questions and answers.

Votes policy

A user must be logged-in to be able to vote. Only supported entities are questions and answers, a user can't vote on a comment.

A user can only vote once on an entity, once he has made a vote, he can cancel it by re-clicking the vote button or can switch to the opposite vote by clicking the opposite vote button. Vote count can be negative.

Similarly as on YouTube where Youtubers can upvote their own videos, users can vote for their own questions and answers. Unlike the real StackOverflow, votes do not currently change how questions or answers are ordered in the list, we sort them by date.

We have a load test plan with JMeter for votes, ensuring that there's no issue with concurrency while multiple users vote on an entity.

Navigation of large amount of data

We choose not to implement a tagging mechanism, or a searching bar, the only navigation mechanism that we implemented is the pagination on questions' list and question details for answers. We set the pagination to 3 elements per page (as we have very few records in the DB for now).

Password policy

Passwords are hashed when stored in the DB, and must be at least 8 characters long, include an uppercase, a lowercase letter and a number.

Possible improvements

To run integration tests, you need an instance of the website before running IT tests inside intelliJ. You can deploy this website by cd'ing in /scripts and run:

  ./startDocker.sh

then run the tests.

Through our various test plans, we didn't find any major issues or problems, but there is always things to tweak and improve, other than the bugs that might have made their way through, we can think of the following improvements :

• Adding more tests (especially JMeter load tests, but all kinds of tests are always welcome, and also tests using Arquillian are not yet implemented) and thus improving coverage.
• Factoring JSP components into fragments (we didn't have the time to do that before the project_1 deadline).
• Implementing a tagging mechanism nor a search bar for easier navigation through large amount of data.
• Improving the CSS.

What has been added since the 22.01.2020 presentation

• CSS was fixed.
• Password and email format verification have been re-enabled.