I have a task that requires me to delete some data in an array that is in a JSON file, using node/express. I want, when a delete request is made, to delete a specific item that matches a specific id in the array that is in the JSON file. I tried using the filter method, but it doesn't seem to work.
JS file:
var obj = { projects: []};
app.post('/', (req, res, next)=>{
let identifier = req.query.identify; //id of project
fs.readFile('webProjects.json', (err, data)=>{
if(err) throw err;
obj = JSON.parse(data);
obj.projects.push({id:identifier, game: req.query.project});
let json = JSON.stringify(obj);
fs.writeFile('webProjects.json', json, (err)=>{
if(err) throw err
console.log("updatedd")
})
})
})
/*when user sends delete request, delete specific data.*/
app.delete("/", (req, res, next)=>{
fs.readFile('webProjects.json', (err, data)=>{
console.log(data)
obj = JSON.parse(data);
obj.projects.filter((item)=>{
let url = req.query.identify;
return item.id !== url;
})
console.log(obj)
let json = JSON.stringify(obj);
fs.writeFile('webProjects.json', json, (err)=>{
if(err) throw err;
console.log(obj)
})
})
})
/*when user navigates to another page, we display the data of the resource*/
app.get('/:id', (req, res, next)=>{
fs.readFile('webProjects.json', (err, data)=>{
if (err) throw err
res.send(data);
})
})
/*we want to catch all errors, with the requests made to the server.
used the wildcard(*) to make sure that we catch all requests made to the server.
*/
app.get('*', (req, res, next)=>{
let err = new Error('There was an error in accessing the page you wanted');
err.statusCode = 404;
next(err);
})
app.use((err, req, res, next)=>{
console.log(err.message)
if(!err.statusCode) err.statusCode = 500;
res.status(err.statusCode).send(err.message);
})
app.listen(8080, ()=>{
console.log("server has listened")
})
JSON file/data:
{"projects":[{"id":"1","game":"miniGame"},{"id":"2","game":"min"}]}
The filter function does not change the array so you need to assign the filtered items back to the array.
fs.readFile('webProjects.json', (err, data)=>{
console.log(data)
obj = JSON.parse(data);
// assign the filtered array back to the original array
obj.projects = obj.projects.filter((item)=>{
let url = req.query.identify;
return item.id !== url;
})
console.log(obj)
let json = JSON.stringify(obj);
fs.writeFile('webProjects.json', json, (err)=>{
if(err) throw err;
console.log(obj)
})
})