Competitive Coding using Travis-CI

We all have used Continuous Integration with our Version Control System but ever wondered we can also host a Competetive Coding Competition on Travis-CI and use it like Hackerearth or Hackerrank!

So How Does it work?

So the Above Flow Gives you a Basic Info of the whole Workflow. But wait this ain’t any informant Blog Post, consider this a step by step guide to deploy your Own Custom Competetive Coding Event on Travis and GitHub!

Step- 1

For Reference, I have already Created a GitHub repository with all the necessary codes and Travis-Config File. Don’t worry at the end of the Blog Post you will be able to Deploy Your own.

• Git Clone this Repository

Club-DevBytes/Clash-of-Coders-in-C-Lang

• You will see .travis.yml file.
• You will see a scripts folder
• These 2 Things are the Heart Here ❤

Prerequisites:

• Create a DropBox App from the Following

https://www.dropbox.com/developers/apps_tk=pilot_lp&_ad=topbar4&_camp=myapps

After you Create your Dropbox App click on Generate Access token and Copy it.

Open The Scripts Folder and open dropbox_uploader.sh file and move to the line number- 1548 and add your access token there.

Add your access token here.

Open DropBox and Create a Cases folder and upload 6 files

• input.txt, input1.txt, input2.txt
• output.txt, output1.txt, output2.txt

These will be the Test case that you upload on Hackerearth or any other coding platforms (Here I considered 3 test cases you can change that if you want)

I recommend you look at this repository where I got the dropbox_uploader.sh code for reference and Usage.

andreafabrizi/Dropbox-Uploader

Once all these setups are done we can write our program of Competetive Coding Coding. Here I have taken a Sample mid-level question — Question can be found in the repository README.md and the solution is in main.c.

Step-2

Lets Head in understanding the Code!!

This is our Travis build file and is quite simple and self-explanatory.

• First I am making our dropbox_uploader.sh file executable using
  chmod +x command.
• Then I am downloading my Input files with our dropbox uploader
• And compiling our main.c with clang
• And then I am doing this :
  ./sample_program < input.txt > stored_output.txt
• What it does is it takes input from input.txt and stores output in output.txt It’s that simple 😉
• After that, I am uploading the stored_output.txt to Dropbox
• In the Python section basically, I am downloading output.txt and stored_output.txt files.
• Now before we move forward let’s open our scripts folder and inside it open test_cases_checker.py
• So if you are familiar with python than you will find this quite easy to understand that what I am doing is opening output.txt files and adding it to python list and also adding stored_ouput.txt and adding it to a python list
• Then I am basically checking if each element of both these lists are same or not
• If they are same then I will print
• Test case 0: Passed
  Test case 1: Passed
  Test case 2: Passed
• If any of the Test Cases fail then I will raise an error and hence build will fail on Travis
• And After that in our travis.yml file, I am Basically deleting our stored_output.txt files from Dropbox for non-test case duplicity reasons for future assessments.
• That’s all this is all that is required for our building a Competetive Code Checker System for using it with Travis and GitHub.

Step 3:

• So let’s start using this Project you can either Fork my repository or you can create your own and push all the code to GitHub.
• After that Open Travis CI Website: https://travis-ci.org and sign in with GitHub.
• After that hover on profile Icon and click on settings.

• After that, you will see your GitHub Repository list and find the one you pushed all your code and turn on the switch beside the repository name.

• Click in more option- trigger build and trigger custom build and this is what you will see.

• Now speedily click on cancel job of python because we need to run python file after we compile our main.c program.

• Once The C job of Travis is compiled perfectly then restart the python job and see that if all the test cases are compiled or not?

You can see that all test cases were passed by the code!

And done 😎😊that's how you just made your own competitive coding platform and isn't it awesome 🤷‍♂️ ?

If you loved or liked my small experiment make sure you hit that
👏 Clap Button and also don't forget to follow me on twitter.

Jainal Gosaliya (@jainal_gosaliya) | Twitter