Logo Questions Linux Laravel Mysql Ubuntu Git Menu
 

Fetch API cannot load file:///C:/Users/Jack/Desktop/Books_H/book-site/public/api/books. URL scheme must be "http" or "https" for CORS request

Just started learning node js in my school. They gave us this half-finished task and i need to make the next and prev buttons work. However i get some errors in the console the moment i run the index.html. The errors are:

"Fetch API cannot load file:///C:/Users/Jack/Desktop/Books_H/book-site/public/api/books. URL scheme must be "http" or "https" for CORS request."

and the other one is :

"Uncaught (in promise) TypeError: Failed to fetch at HTMLDocument.document.addEventListener".

I dont even know how to start to solve this problem. Any help?

    <!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=1000, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Hello</title>
</head>
<body>
    Hello from the other side! <b>Total: <span id="total"></span></b><br/>
    <button id="author">Sort by author</button>
    <button id="title">Sort by title</button>
    <table id="books" border="1">
        <tr>
            <th>
                Author
            </th>
            <th>
                Book Title
            </th>
        </tr>

    </table>
    <script src="index.js"></script>
</body>
</html>

The java script file

    document.addEventListener("DOMContentLoaded", () => {
    processResponse(fetch("api/books"));

    document.getElementById("author").addEventListener("click", () =>{
        processResponse(fetch("api/books?sortby=author"))
    });

    document.getElementById("title").addEventListener("click", () =>{
        processResponse(fetch("api/books?sortby=title"))
    });

});

function processResponse(response) {
    let table = document.getElementById("books");
    let total = document.getElementById("total");

    response.then(data => data.json())
        .then(value => {
            table.innerHTML = "";
            const tr = document.createElement("tr");
            let th = document.createElement("th");
            th.innerHTML = "Author";
            tr.appendChild(th);
            th = document.createElement("th");
            th.innerHTML = "Book Title";
            tr.appendChild(th);
            table.appendChild(tr);
            for (let index = 0; index < value.books.length; index++) {
                const book = value.books[index];
                const tr = document.createElement("tr");
                let td = document.createElement("td");
                td.innerHTML = book.author;
                tr.appendChild(td);
                td = document.createElement("td");
                td.innerHTML = book.title;
                tr.appendChild(td);
                table.appendChild(tr);
            }
            total.innerHTML = value.total;
        });
}

server.js file

    const fs = require('fs');
const express = require('express');
const app = express();

app.use(express.static("public"));

app.get("/", (req, res) => {
    res.sendFile("index.html", { root: __dirname + "/public" });
});

const apiRouter = express.Router();

apiRouter.get("/books", (req, res) => {

    let sortOrder = req.query["sortby"];

    fs.readFile("data/books.json", { encoding: 'utf8' }, (err, data) => {
        if (err) {
            console.error("ERROR is: ", err);
            return;
        }

        let books = JSON.parse(data);
        if (sortOrder === "author") {
            books.sort((a, b)=> a.author.localeCompare(b.author));
        } else if (sortOrder === "title") {
            books.sort((a, b)=> a.title.localeCompare(b.title));
        }

        res.send(JSON.stringify({
            books: books.slice(0, 50),
            total: books.length
        }));
    });
})

apiRouter.get("/books/title", (req, res) => {
    fs.readFile("data/books.json", { encoding: 'utf8' }, (err, data) => {
        if (err) {
            console.error("ERROR is: ", err);
            return;
        }

        let books = JSON.parse(data);
        let titles = books.map(book => book.title);
        res.send(JSON.stringify(titles));
    });
})

apiRouter.get("/books/author", (req, res) => {
    fs.readFile("data/books.json", { encoding: 'utf8' }, (err, data) => {
        if (err) {
            console.error("ERROR is: ", err);
            return;
        }

        let books = JSON.parse(data);
        let authors = books.map(book => book.author);
        res.send(JSON.stringify(authors));
    });
})


app.use("/api", apiRouter);


app.listen(8080, () => console.log('Example app listening on port 8080!'));

/*
And the books.json file that i guess you dont need so i wont post it.
My folder structure is:

Books > data Folder > books.json. 
Books > public Folder > index.html. 
Books > public Folder > index.js.
Books > server.js.
*/
like image 704
Happy Coconut Avatar asked Feb 11 '18 04:02

Happy Coconut


People also ask

How do I respond to a fetch API in HTML?

You can use the text() method to get the response as an HTML string. The text() method returns the response body as a string. Read this article to learn more about Fetch API response formats.

How do I get fetch from API response?

Approach: First make the necessary JavaScript file, HTML file and CSS file. Then store the API URL in a variable (here api_url). Define a async function (here getapi()) and pass api_url in that function. Define a constant response and store the fetched data by await fetch() method.

How can I fetch data from API?

The Fetch API allows you to asynchronously request for a resource. Use the fetch() method to return a promise that resolves into a Response object. To get the actual data, you call one of the methods of the Response object e.g., text() or json() . These methods resolve into the actual data.

What does it mean to fetch an API?

The Fetch API provides a JavaScript interface for accessing and manipulating parts of the protocol, such as requests and responses. It also provides a global fetch() method that provides an easy, logical way to fetch resources asynchronously across the network.


1 Answers

Well this is what i had to do if it helps anyone in the future at all. This is all basic stuff but i am beginner so here we go. Open command prompt. Go to the destination of your project( where the index.js file is ) and write:

$ npm init -y
$ npm install -g express-generator
$ npm install express -S
$ npm install connect -S
$ npm install serve-static -S

then go to the destination of your server.js file and write

$ node server.js

After this i could run my page in browser typing http://localhost:8080/ in the URL.

like image 122
Happy Coconut Avatar answered Oct 14 '22 14:10

Happy Coconut