This repository contains an implementation of a minimal back-end (database and HTTP server) that aims to partially recreate an existing quiz service.
The project is implemented with Clojure and MySQL.
Please see docs/architecture.md for notes on design and architecture.
Using the service requires installation of docker-compose and leiningen (tool for managing Clojure projects). See the following resources for help:
The service uses a dockerized MySQL database. This service may be initialized with docker-compose.
Assuming docker-compose is properly installed, the database may be started as follows:
export DB_PORT=3306 # assign port associated with db
docker-compose up
Schema migration is managed using a Clojure library called ragtime, which is integrated into the Clojure project definition.
To perform schema migration, run the following command from the root of the project directory:
lein migrate
Such schema migrations can be undone using the complementary command:
lein rollback
Gracefully shut down the service from the db/ subdirectory.
docker-compose down
Assuming leiningen is properly installed, the server may be built as follows:
lein do clean, deps, install
This command clears the existing target directory (if it exists), downloads associated dependencies to the user's m2 cache, and prepares the project to be run locally.
Use of the service requires that the dockerized mysql database is available over the configured URL (see Installation for details).
Run the server on localhost as such:
export API_PORT=3000
lein run
Port 3666 is used by default. However, the API_PORT environment variable may be used to select another port.
In the context above, the server is available at url: http//localhost:3000/.
Please see the api description document included in docs/api.md.
Please note sample json messages are included in the samples/ directory at the root of this repository.
A set of tests packaged in the Clojure projects behaviorally probe the server and associated session-management logic.
These tests may be run using lein:
lein test
Please note that running these commands effectively restarts the state of the database (rollback migration is performed).
The current implementation could be improved upon in several ways:
-
The user should get confirmation that a session as successfully been submitted. The current api gives confirmation of submission when the calling application requests to close the session, but a more robust solution might be beneficial. One such solution is to delegate this responsibility to a separate email/notification service.
-
The current implementation accommodates limited question and answer data. An improved implementation might serve assets (e.g., images) through a dedicated route. Question text could be embedded in a richer medium, like HTML or markdown that supports references to such assets. A preliminary solution for storing such assets might be AWS/S3, but options providing a nice story for versioning might be preferred.