Dodona is an online exercise platform for learning to code. It wants to teach students how to program in the most meaningful and effective way possible. Dodona acts as an online co-teacher, designed to give every student access to high quality education. The focus is on automatic corrections and giving meaningful feedback on the submitted solutions from students.
This repository contains the source code of the web application. If you simply want to use Dodona, please go to https://dodona.ugent.be.
The documentation for end users can be found at https://docs.dodona.be.
Dodona is free to use for schools and we would like to keep it that way! Keeping this platform up and running takes a lot of time, just as supporting hundreds of schools and thousands of students. If you would like to fund Dodona, you can find more information on https://dodona.ugent.be/en/support-us/ or get in touch by emailing us at dodona@ugent.be.
There are several ways to contact us:
- To report a bug, please use GitHub Issues.
- If you have a question to which the answer might be of use to others, please use GitHub Discussions.
- For more specific questions, use our contact form, send an email to dodona@ugent.be or come chat with us in our general chat or our support chat.
If you want to help with development, issues tagged with the student label are a good starting point.
- Install and start
mysql
ormariadb
. - If using
mysql
, change thesql-mode
in themysqld
configuration block:sql-mode='STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION'
- Create a
dodona
user with access to thedodona
anddodona_test-N
databases. You will need as much test databases as hou have CPU threads.CREATE USER 'dodona'@'localhost' IDENTIFIED BY 'dodona'; GRANT ALL ON dodona.* TO 'dodona'; GRANT ALL ON dodona_test.* TO 'dodona'; GRANT ALL ON dodona_test-0.* TO 'dodona'; ... GRANT ALL ON dodona_test-3.* TO 'dodona';
- Create and seed the database with
rails db:setup
. (If something goes wrong with the database, you can userails db:reset
to drop, rebuild and reseed the database.) If the error "Could not initialize python judge" arises, useSKIP_PYTHON_JUDGE=true rails db:setup
- Start the server. The simplest way is with
rails s
. Dodona will be available on a subdomain of localhost: http://dodona.localhost:3000. - Because CAS authentication does not work in development, you can log in by going to these pages (only works with the seed database from step 4)
http://dodona.localhost:3000/nl/users/1/token/zeus
http://dodona.localhost:3000/nl/users/2/token/staff
http://dodona.localhost:3000/nl/users/3/token/student
These steps are not required to run the server, but you need docker to actually evaluate exercises.
- Install and start
docker
. - Clone the docker-images repository.
- Build a docker image. The
build.sh
scripts builds all images. But with the initial data, onlydodona-python
is needed. You can build this image withdocker build --pull --force-rm -t "dodona-python" -f "dodona-python.dockerfile" .
.
These steps are not required to run the server, but are needed to let the visualisations load.
- Install and start
memcached
. - Create the following file
tmp/caching-dev.txt
.
Some gems and dependencies (such as memcached) do not work on Windows. You should use WSL 2 instead, and run everything inside WSL. This means you use WSL for the database, memcached, git, Docker, etc.
The simplest way to start the server is with the rails s
command. But this will not process the submission queue, and javascript will be compiled by webpack in the background (without output when something goes wrong).
- To process the submission queue, delayed job needs to be started with the
bin/delayed_job start
command. - With
bin/webpack-dev-server
your javascript is reloaded live and you can see development output.
To start the rails server, delayed job and the webpack dev server at the same time, simply run bin/server
.
This has one letdown: debugging with byebug
is broken.
Dodona uses subdomains in order to sandbox exercise descriptions (which are arbitrary HTML pages and could be used for malicious purposes if not properly sandboxed). We serve the main application in development from http://dodona.localhost:3000 and exercise descriptions from http://sandbox.localhost:3000.
If this does not work out of the box you can add the following lines to your /etc/hosts
file:
127.0.0.1 dodona.localhost
127.0.0.1 sandbox.localhost
To lint the code, run rubocop
for Ruby and yarn lint
for JavaScript.
We have tests in JavaScript, Ruby, and system tests:
- For JavaScript, run
yarn test
- For the system tests, run
bundle exec rails test:system
- For the ruby tests, run
bundle exec rails test
Tips
- Use the
PARALLEL_WORKERS
ENV var to specify the number of threads to use. - Use
TestProf
to profile the ruby tests - Use
bundle exec rails test filename
to run a single test file, usebundle exec rails test filename:linenumber
to run a specific test