dCoders

Description

Our idea is about an online coding competition website based on blockchain. Where anonymously, users can participate in an event that is organized based on a threshold count of registrations. If enough members do not participate in the event that is scheduled, then it won't be organized. In our idea, a participant has to pay a nominal fee in the form of ether, bitcoin, other crypto-currency. The pooled crypto-currency will be distributed among the winning participants. Our portal will allow events to be held frequently and that too when people actually are ready to participate. This concept provides anonymous participation in coding competitions held regularly where winners get their prizes very qickly with the security features of blockchain. We have developed this 'Coders Unknown Battle Portal'.

Contributors:

• Hrishabh Sharma
• Aman Pandey
• Ujjwal Kumar
• Jay Rathod

Model design

• User-end

  1. Browser
  2. Metamask Extension
  3. web3js

• Server

  1. conventional database (storing code submissions and people pool)
  2. judge0 api (users' source code evaluation)
  3. web3js (interaction with blockchain for registration and winning transaction)

• Blockchain

  Already available on the ethereum platform

• API (judge0 api)

  Already available

Pooling System

In the pooling system users are kind of listed for the event. At this stage no transaction is performed (transfer of crypto-currency). The time of event is already fixed and participants will be allowed make the payment before the event start time. Once enough number of people are listed, they have to do the transaction (transfer ether) of a significant amount in a 30 minute span for participating in the event.

At the event start time a check is performed if enough people have transacted to take part. If not, then the transaction will be reverted back to the already registered participants.

The Event

Once enough people have transacted for the participation, the event will start. Questions for the event are displayed once the event start timme hits. The participants will submit their solution in an online ide and their submissions will be stored in our servers' database. On completion of the event, a winner will be decided based on the submissions made and the pooled ether (crypto-currency) will be distributed among the top performers.

The Submission and Online Judge

The submissions to the event will be performed through our online ide. Our system will make use of an api of an online judge (namely, Judge0) to compile, run and check the submissions. On submission, the source code and other required details are captured from client side and sent to our servers. Our servers make use of judge0 api to judge the submission. Each submission and its judgement result is stored in a conventional database.

The Winners

On the completition of event, the top performers are decide based on the submissions

Troubleshooting

• mysql root password reset

  sudo mysqld_safe --skip-grant-tables& sudo mysql --user=root mysql

  Do this only if the following error appears on using above command:- mysqld_safe Directory '/var/run/mysqld' for UNIX socket file don't exists

  mkdir -p /var/run/mysqld chown mysql:mysql /var/run/mysqld

  mysql> update user set authentication_string=PASSWORD('new-password') where user='root'; flush privileges; quit

  sudo service mysql restart sudo mysql -u root -p

References

• Creating Node.js Application
• Render file
• Serve static file
• Add user and grant permissions to mysql
• Connect mysql to nodejs express server
• Create SQL tables
• Sleep in javascript
• Get access to accounts in privacy-mode
• Autoreload node server
• MYSQL in node-express
• Parse POST request in nodejs-express server | Video | Doc | Article
• MYSQL error str_to_date
• Export/Import mysql database
• Date in sql to javascript format
• Create and export/import objects from js file
• Promises in javascript