发布请求-以json格式发送数据

Question

I have a study project. Have a simple form with input and button. Need to save an input value into JSON file. HTML

<form action="/" method="post" id="emailForm">
    <input type="email" id="email" name="email" placeholder="Enter email for newsletter">
    <button type="submit" id="subscribe" value=""><i class="fas fa-chevron-right"></i></button>
</form>

JS to convert data into JSON format

$('#subscribe').on('click', function (event) {
        // prevent from reloading the page
        event.preventDefault();
        // checking validity of input
        if (ValidateEmail()) {
            var formData = $("#emailForm").serializeArray();
            $.each(formData, function () {
                if (jsonData[this.name]) {
                    if (!jsonData[this.name].push) {
                        jsonData[this.name] = [jsonData[this.name]];
                    }
                    jsonData[this.name].push(this.value || '');
                } else {
                    jsonData[this.name] = this.value || '';
                }

                jsonData = JSON.stringify(jsonData);

            });

            console.log(jsonData);


            $.ajax({
                url: "app.js",
                type: "POST",
                dataType: 'json',
                data: jsonData

            }); 
            alert('Email saved!');
            return jsonData;

        } else {
            console.log('email not saved');
        }
    });

app.js

const fs = require('fs');

fs.readFile('email.json', (err, data) => {  
    if (err) throw err;
    let email = JSON.parse(data);
    console.log('original' + email);
});
fs.writeFileSync('email.json', jsonData);  
console.log('done');

the problem is with accessing file app.js - first, it's blocked by chrome

Access to XMLHttpRequest at 'file:///D:/HTML/Try%20it/acad/master/app.js' from origin 'null' has been blocked by CORS policy: Cross-origin requests are only supported for protocol schemes: HTTP, data, chrome, chrome-extension, https

Tried to run a local server with node.js and received Error 405 (Method Not Allowed).

Answer 1

Your app.js is just a script, that start to read a file, write one by blocking the thread, print 'done' and shutdown. No HTTP server, no request handling...

What you need first is to set up a HTTP server, this can be done with the native http node.js module, or with other modules (like express ), so that you listen for events, and trigger code when a the server is called.

Also, the http-server is made to quickly render some files, trying to POST to a text file obviously do nothing, and if you were to GET it, you would simply get you text file, which do you no good.

So depending on what are your homework constraint, you need to either check http , or express documentation, set up a valid HTTP server, and on that call, correctly write to your file.

(Tips: Do not use ...Sync function in node.js, unless you really do know what you are doing, and check what "asynchronous" functions are, you will need it)