index.js

const Joi = require('joi');
const express = require('express');
const app = express();
app.use(express.json());

courses=[
    { id: 1, name: 'course1'},
    { id: 2, name: 'course2'},
    { id: 3, name: 'course3'}

  
];
app.get('/',(req,res) => {
    res.send('hellooo theree !!!');

});
app.get('/api/courses',(req,res) => {
    res.send(courses);
});
app.post('/api/courses',(req,res) => {
    const {error} = validatecourse(req.body);
    if(error) return res.status(400).send(result.error.details[0].message);
    const course = {
        id: courses.length + 1,
        name: req.body.name
    };
    courses.push(course);
    res.send(course);
});

app.put('/api/courses/:id',(req,res) => {
    const course = courses.find(c => c.id === parseInt(req.params.id));
    if(!course) return res.status(404).send('course now found');

    const {error} = validatecourse(req.body);
    if(error) return res.status(400).send(result.error.details[0].message);

    course.name = req.body.name ;
    res.send(course);
});
function validatecourse(course)
{
    const schema = {
        name: Joi.string().min(3).required()
    };
    return Joi.validate(course, schema);

}
app.delete('/api/courses/:id',(req,res) => {
    const course = courses.find(c => c.id === parseInt(req.params.id));
    if(!course) return res.status(404).send('course now found');

    const index = courses.indexOf(course);
    courses.splice(index,1);
    res.send(course);

});

app.get('/api/courses/:id',(req,res) => {
    const course = courses.find(c => c.id === parseInt(req.params.id));
    if(!course) return res.status(404).send('course now found');
    res.send(course);
});
const port = process.env.PORT || 3000 ;
app.listen(port, () => console.log(`app is listinig on ${port}`));