I need some help getting parameters to go through with my AJAX call-CodePudding

I'm making a call with ajax to my db to get some data. And I try to limit it to a specific Id. And I got the backend working. it works when I visit the specific localhost url or when I call it from Postman. I then get the expected value. However when I try to make a call from my client with AJAX I just don't get anything at all. I got into a thing where sometimes it would work and sometimes it didn't.

const GetUserById = (id) => {
    let url = "/Users/1";
    $.get(url, (gotUser) => {
        alert(gotUser.id);
    })
}

I have this method that I just hardcoded to go to /Users/1 for testing purposes. And when I call this in postman or go to localhost:8080/Users/1 I get the thing I expect. However here It just doesn't go anywhere at all.

app.get("/Users/:id", (request, response) => {
    let sqlCode = "select Id, Username, [Password], Credits from Users Where Id = "   request.params.id;

    sql.query(connString, sqlCode, (error, result) => {

        if (error) {
            console.log(error);
        }
        else {
            response.json(result);
        }
    });
});

The server side if that's interesting.

EDIT: added a try catch like this. it doesn't even get to the catch. It get's to the line that's $.get(url, (gotUser) => { then it goes to the end of the function and doesn't get anything.

 try {
        $.get(url, (gotUser) => {
            alert(gotUser.id);
        })
    } catch (error) {
        console.log(error);
    }

CodePudding user response：

A typical issue with processing the ajax requests are the CORS. In your case a quick fix to that would be to specify at the response headers to allow the origins, like that:

response.header("Access-Control-Allow-Origin", "*");
response.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");

In a more general way you might need to specify that in application level, or use any package to deal with that.
EDIT ---

app.get("/Users/:id", (request, response) => {
response.header("Access-Control-Allow-Origin", "*");
response.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");

    let sqlCode = "select Id, Username, [Password], Credits from Users Where Id = "   request.params.id;

    sql.query(connString, sqlCode, (error, result) => {

        if (error) {
            console.log(error);
        }
        else {
            response.json(result);
        }
    });
});

CodePudding user response：

If it is a cors issue try something along these lines

var cors = require('cors');
    
app.get("/Users/:id",cors(), (request, response) => {
            let sqlCode = "select Id, Username, [Password], Credits from Users Where Id = "   request.params.id;
        
sql.query(connString, sqlCode, (error, result) => {
        
     if (error) {
                    console.log(error);
                }
                else {
                    response.json(result);
                }
            });
        });