I'm beginner and trying to make a function findByID with NodeJS and JSON file as a database without frameworks, code:
const http = require("http");
const url = require("url");
const fs = require("fs");
const querystring = require("querystring");
const data = fs.readFileSync("./data/data.json");
let todos = JSON.parse(data);
const server = http.createServer((req, res) => {
const urlparse = url.parse(req.url, true);
if (urlparse.pathname == "/todos" && req.method == "GET") {
const search = urlparse.search;
if (search) {
const [, query] = urlparse.search.split("?");
const data = querystring.parse(query);
todos = todos.filter((todo) => todo.id === data.id);
res.end(JSON.stringify(todos, null, 2));
}
}})
When I check with postman for the first time everything is fine. 1st request
When I check the second time in the response window there is an empty array.2nd request
Each request used a different id.
I dont see todos defined so I assume it’s global, this line is then mutating it every request:
todos = todos.filter((todo) => todo.id === data.id);
Another thing is if id is unique you could use todos.find to just get the first match.
So instead use a new variable and find:
const todoMatch = todos.find((todo) => todo.id === data.id);