无法关注其他用户

Question

So I have a following system that allows you to follow users. So here's the code of follow.php

<?php
error_reporting(0);

session_start();

include_once 'db.php';

$username =  htmlspecialchars($_GET['fuser'], ENT_QUOTES, 'UTF-8');
$follower = $_SESSION['user'];
$type = 'Following';


if($username == $follower){
    header('Location: index.php');
}


if($_SESSION['loggedIn'] == true && $follower != $username){
    $result = $con->prepare("SELECT * FROM followers WHERE follow_to = :post_id");
    $result->bindParam(':post_id', $username);
    $result->execute();
    $reprint = $result->rowCount();
}

if($result->rowCount() < 1){
    //Notifcation handler 
    $notf = $con->prepare("INSERT INTO notifications (from_user, to_user, type) VALUES (:cuser, :tuser, :type)");
    $notf->bindValue(':cuser', $_SESSION['user'], PDO::PARAM_STR);
    $notf->bindValue(':tuser', $username, PDO::PARAM_STR);
    $notf->bindValue(':type', $type, PDO::PARAM_STR);
    $notf->execute();

    //Insert into followers
    $stmt = $con->prepare("INSERT INTO followers (follow_from, follow_to) VALUES (:ff, :ft)");
    $stmt->bindValue(':ff', $follower, PDO::PARAM_STR);
    $stmt->bindValue(':ft', $username, PDO::PARAM_STR);
    $stmt->execute();

}
//Display follower
$stmt1 = $con->prepare("SELECT COUNT(*) AS count FROM followers WHERE follow_to = :username");
$stmt1->bindValue(':username', $username, PDO::PARAM_STR);
$stmt1->execute();
$likes = $stmt1->fetchAll(PDO::FETCH_ASSOC);

$qry = $con->prepare("SELECT follow_from, follow_to FROM followers");
$qry->execute();
$followers = $qry->fetchAll(PDO::FETCH_ASSOC);
header('Location: ' . $_SERVER['HTTP_REFERER']);
exit();

?>

And what happens is when I try following a user all that happens is I get redirect to $_SERVER['HTTP_REFERER']. This makes me think that the last if statement isn't being processed. So here's the table layout

+-------------+------------------+------+-----+---------+----------------+
| Field       | Type             | Null | Key | Default | Extra          |
+-------------+------------------+------+-----+---------+----------------+
| id          | int(11) unsigned | NO   | PRI | NULL    | auto_increment |
| follow_from | varchar(255)     | YES  |     | NULL    |                |
| follow_to   | varchar(255)     | YES  |     | NULL    |                |
+-------------+------------------+------+-----+---------+----------------+

I think that this might be an issue with my query. Any ideas?

Answer 1

I suggest making the following changes. In your original post, you are looking in the follower tables for ANY record where the follow_to is the person that you wish to follow. Meaning that if someone else is following this user, based on your logic the new following action will not occur.

I modified your initial sql to check for a record where the logged in user is already matched up as following the requested user.

I'm adding a $reprint variable initialized to 0. If no user is logged in, nothing will happen. If the user is logged in, but no record exists in the followers table, it inserts the new entries into both followers and notification.

Otherwise, it doesn't insert and does the remaining parts of your script.

<?php
error_reporting(0);

session_start();

include_once 'db.php';

$username =  htmlspecialchars($_GET['fuser'], ENT_QUOTES, 'UTF-8');
$follower = $_SESSION['user'];
$type = 'Following';


if($username == $follower){
    header('Location: index.php');
}

$reprint = 0;

if($_SESSION['loggedIn'] == true && $follower != $username){
    $result = $con->prepare("SELECT * FROM followers WHERE follow_to = :post_id and follow_from = :from");
    $result->bindParam(':post_id', $username);
    $result->bindParam(':from', $follower);
    $result->execute();
    $reprint = $result->rowCount();
}

if($reprint < 1){
    //Notifcation handler 
    $notf = $con->prepare("INSERT INTO notifications (from_user, to_user, type) VALUES (:cuser, :tuser, :type)");
    $notf->bindValue(':cuser', $_SESSION['user'], PDO::PARAM_STR);
    $notf->bindValue(':tuser', $username, PDO::PARAM_STR);
    $notf->bindValue(':type', $type, PDO::PARAM_STR);
    $notf->execute();

    //Insert into followers
    $stmt = $con->prepare("INSERT INTO followers (follow_from, follow_to) VALUES (:ff, :ft)");
    $stmt->bindValue(':ff', $follower, PDO::PARAM_STR);
    $stmt->bindValue(':ft', $username, PDO::PARAM_STR);
    $stmt->execute();

}
//Display follower
$stmt1 = $con->prepare("SELECT COUNT(*) AS count FROM followers WHERE follow_to = :username");
$stmt1->bindValue(':username', $username, PDO::PARAM_STR);
$stmt1->execute();
$likes = $stmt1->fetchAll(PDO::FETCH_ASSOC);

$qry = $con->prepare("SELECT follow_from, follow_to FROM followers");
$qry->execute();
$followers = $qry->fetchAll(PDO::FETCH_ASSOC);
header('Location: ' . $_SERVER['HTTP_REFERER']);
exit();

?>