The what, why, and how:
Final portfolio project for ALX back-end track graduation Every year, Ethiopian high school seniors seat for their national university entrance exam. They are given above 80 multiple choice questions for about 7 subjects. This project is a contains a REST API for developers to fetch national exam questions from the year 2005-2010(Ethiopian calendar) with an API key. It also let's them check the answers returned by the user.
Steps required to install project and how to get the development environment running:
- clone this github repo(https://github.com/Heyeman/alx-backend_project)
- change your directory to alx-backend_project with
cd alx-backend_project - install the required dependency list with
npm install - execute the project with
node index
- if the server starts with no error, the following is printed to the console
Server listening to port 5000
MySQL with Prisma connected
Database connected successfully
- Node.js
- express.js and express async handler
- mongoose
- prisma & prisma client
- bcrypt
- jsonwebtoken
- colors
create an .env file with the following content:
MONGO_DB_URI - mongo database uri
JWT_SECRET - jwt secret
DATABASE_URL - MySQL questions database url
|—— .env
|—— .gitignore
|—— backend
| |—— app.js
| |—— config
| |—— dbConn.js
| |—— controllers
| |—— authControllers.js
| |—— examControllers.js
| |—— keyControllers.js
| |—— helpers
| |—— 404handler.js
| |—— eventListener.js
| |—— tokenGen.js
| |—— middlewares
| |—— errorHandler.js
| |—— keyChecker.js
| |—— routeProtector.js
| |—— models
| |—— apiKeyModel.js
| |—— questionModel.js
| |—— resStatusModel.js
| |—— userModel.js
| |—— routes
| |—— authRoutes.js
| |—— examRoutes.js
| |—— keyRoutes.js
| |—— subjectRoutes.js
|—— index.js
|—— prisma
| |—— schema.prisma
Instructions and examples for use:
- use
/authfor authentication
- POST - /auth/login - requires email and password to authenticate a user.
- POST - /auth/register - registers a user with username, password and username. This automatically creates an API key for the user and returns that.
- login/register endpoints in this route return the user's id, email, access token, api key(when registering)
- GET /me - returns the user's info(id, email and name)
- use
/examto get exams and exam checking service
Whenever an api request is done to this path, the middleware keyChecker is invoked first to check if the user has a valid API request key.
The API key should be put in the 'request-key' header when trying to make a request.
- If there's no API key, the system responds with 'No API key provided' with a status code of 400.
- If there's an API key provided and is not found/valid, the system responds with 'API request key not found'
- If the API key provided is found in the database, the request is passed onto 'examRoutes' router.
- Get - / returns a json list of all subjects.
- If the request is done with a subject parameter like '/:subject' the request is passed unto the 'subjectRoutes' router.
- use
/exam/:subject/
- GET /:year - if the year is between 2005-2010 - it fetches questions of that subject from the year specified from the database.
- POST /:year - checks the answers given by the user
Assuming grade is either 11 or 12,
- GET /:year/:grade - fetches questions of that subject from the year and grade specified from the database.
- POST /:year/:grade - checks the answers given by the user from the questions of that subject, year and grade.
- GET /:year/:grade/:chapter - fetches questions of that subject from the year and grade specified from the database. This selects questions from a single chapter only.
- POST /:year/:grade/:chapter - checks the answers given by the user from the questions of that subject, year and grade.
signup/registration
- The user is required to input email, name and password. If any of these is absent, an error is returned.
- The email is checked if it exists in the database, if it does, an error will be returned.
- If the above two are alright, a password encrypted hash is generated with `bcrypt` and then the API key is generated with the `genKey` helper function. At last, the helper function `genToken` generates an access token and these are returned to the user.
- Assigning parameters
- When the route begins with the `subject` path, the system assigns the subject the the req object with `subject` key.
- The year param is also assigned to the year key of the req object.
- If chapter and grade are also present in the request path, they are assigned to chapter and grade keys of the req object respectively.
- Fetching of questions
A database query object is prepared by using the parameters subject, year, chapter and grade(if present) and then a database call will be executed by the prepared query object.
- getQuestions controller handles this
- Checking the answers
A similar procedure of fetching the questions based on the path parameter occurs here to filter the questions and answers. But the API key should have a pro plan to proceed.
- After the questions are filtered, a hashmap consisting of question ID as a key and question answer as a value is prepared from the entered request parameters.
- After that, by going through every question answer provided by the user, the user's answer is checked against the hashmap and the ID is deleted from the hashmap.
- If the ID is found in the hashmap and the answer is correct, correctAnswers increases by 1, else, incorrectAnswers increases by 1 then the ID is deleted from the hashmap.
- If the ID is not found in the hashmap, the question is invalid, so invalidQuestions increases by 1.
- If the hashmap is not empty, the number of elements in the hashmap is returned as the number of questions the user did not answer.
- Returning the results
- 200 - request is successful
- 400 - request is not successful(the user's fault)
- 401 - request is not successful(the user did not provide necessary auth credentials)
- 403 - request is not successful(the user is not authorized to perform the request)
- 404 - request is not successful(the user did not provide a valid path)
MIT License
For any questions, please contact me with the information below:
- Email: [email protected]
Heyeman Urgessa - Github
