Develop Reference

unable to parse xml data with AJAX + Wordpress

Ok, I am officially stumped. I have been trying to find why my calls for specific items in a PubMed xml data file are not working... I can execute this one with my current coding:
$test = (string)$id_json->PubmedArticle->MedlineCitation->PMID;
but if I try to get a variable that is in a deeper array, it does not return a value. I have even tested with console.log(data) and I get my PMID returning but not my other, deeper values in the XML file. For example;
$test = (string)$id_json->PubmedArticle->MedlineCitation->Article->Journal->ISSN;
returns nothing for data in console.log(data)
Here is my function in wordpress:
function get_abstract(){
$id = $_POST['abstractid'];
$pubmed_api_call = 'https://eutils.ncbi.nlm.nih.gov/entrez/eutils/efetch.fcgi?db=pubmed&retmode=xml&rettype=abstract&id='.$id;
$id_wpget = wp_remote_get($pubmed_api_call, array('timeout' => 20));
if( is_wp_error( $id_wpget ) ) {
echo "Error Contacting PubMed, please refresh page and try again";
die();
}
$id_xml = wp_remote_retrieve_body($id_wpget);
$id_json = simplexml_load_string($id_xml);
$test = (string)$id_json->PubmedArticle->MedlineCitation->Article->Journal->ISSN;
if($test === ""){
echo "NOTHING";
die();
}
echo $test;
die();
}
and here is my javascript AJAX call:
jQuery(document).ready(function() {
jQuery('.reference_header').click(function(e) {
jQuery(this).find("i").toggleClass("arrow-down arrow-up");
jQuery(this).nextUntil('.reference_header').slideToggle('fast');
var abstractid = jQuery(this).data("id");
e.preventDefault();
jQuery.ajax({
url: get_abstract.ajaxurl,
type: 'POST',
dataType: 'json',
data: {
abstractid: jQuery(this).data("id"),
action: 'get_abstract'
},
success : function(data){
jQuery('.'+abstractid).html("TESTING: "+data);
console.log(data);
}
});
});
});
I cannot find out why it doesnt work... any help is greatly appreciated.

So I figured out the solution to the issue... you need to pass the string text as a json object to AJAX for it to read properly...
working code:
PHP:
echo json_encode(array("result" => "$test"));
die();
AJAX:
success : function(data){
jQuery('.'+abstractid).html("TESTING: "+data.result);
console.log(data.result);
}

Delete post using $.ajax

I am new to $.ajax and don't know so much and i have following button to delete user post by article ID
<button type="button" onclick="submitdata();">Delete</button>
When click this button then following $.ajax process running.
<script>
var post_id="<?php echo $userIdRow['post_id']; ?>";
var datastring='post_id='+post_id;
function submitdata() {
$.ajax({
type:"POST",
url:"delete.php",
data:datastring,
cache:false,
success:function(html) {
alert(html);
}
});
return false;
}
</script>
And delete.php is
<?php
// connect to the database
include 'conn.php';
$dbClass = new Database();
// confirm that the 'post_id' variable has been set
if (isset($_GET['post_id']) && is_numeric($_GET['post_id'])) {
// get the 'post_id' variable from the URL
$post_id = $_GET['post_id'];
// delete record from database
if ($userPostsQuery = $dbClass::Connect()->prepare("DELETE FROM user_posts WHERE post_id = :post_id")) {
$userPostsQuery->bindValue(":post_id", $post_id, PDO::PARAM_INT);
$userPostsQuery->execute();
$userPostsQuery->close();
echo "Deleted success";
} else {
echo "ERROR: could not prepare SQL statement.";
}
}
?>
This code not working post not deleted. Please how do I do?

You likely want to not only match the "GET" you use in your PHP but also add the ID to the button
<button class="del" type="button"
data-id="<?php echo $userIdRow['post_id']; ?>">Delete</button>
using $.get which matches your PHP OR use $.ajax({ "type":"DELETE"
$(function() {
$(".del").on("click", function() {
$.get("delete.php",{"post_id":$(this).data("id")},
function(html) {
alert(html);
}
);
});
});
NOTE: Please clean the var
Do htmlspecialchars and mysql_real_escape_string keep my PHP code safe from injection?
Using ajax DELETE with error handling
$(function() {
$(".del").on("click", function() {
$.ajax({
url: "delete.php",
method: "DELETE", // use "GET" if server does not handle DELETE
data: { "post_id": $(this).data("id") },
dataType: "html"
}).done(function( msg ) {
$( "#log" ).html( msg );
}).fail(function( jqXHR, textStatus ) {
alert( "Request failed: " + textStatus );
});
});
});
In the PHP you can do
if ($_SERVER['REQUEST_METHOD'] === 'DELETE') {
$id = $_REQUEST["post_id"] ....
}

since you're sending a post request with ajax so you should use a $_POST iin your script and not a $_GET
here is how it sould be
<?php
// connect to the database
include 'conn.php';
$dbClass = new Database();
// confirm that the 'post_id' variable has been set
if (isset($_POST['post_id']) && is_numeric($_POST['post_id'])) {
// get the 'post_id' variable from the URL
$post_id = $_POST['post_id'];
// delete record from database
if ($userPostsQuery = $dbClass::Connect()->prepare("DELETE FROM user_posts WHERE post_id = :post_id")) {
$userPostsQuery->bindValue(":post_id", $post_id, PDO::PARAM_INT);
$userPostsQuery->execute();
$userPostsQuery->close();
echo "Deleted success";
} else {
echo "ERROR: could not prepare SQL statement.";
}
}
?>
for the JS code
<script>
var post_id="<?php echo $userIdRow['post_id']; ?>";
function submitdata() {
$.ajax({
type:"POST",
url:"delete.php",
data:{"post_id":post_id},
cache:false,
success:function(html) {
alert(html);
}
});
return false;
}
</script>
here i've supposed thqt the give you the real id post you're looking for !!

The reason is pretty simple. You should change your request type to GET/DELETE instead of POST. In PHP you expect GET request but in AJAX you send POST request
Change:
type:"POST",
url:"delete.php",
data:datastring,
to
type:"DELETE",
url:"delete.php?" + datastring,
in PHP
if ($_SERVER['REQUEST_METHOD'] === 'DELETE' && !empty($_REQUEST["post_id") {
$id = $_REQUEST["post_id"];
// perform delete
}
DELETE is actually the only valid method to delete objects. POST should create an object and GET should retrieve it. It may be confusing at first time but it's good practicet specially used in REST APIs. The other one would be UNLINK if you wanted to remove relationship between objects.

Follow #roberts advise and also:
You should have a way to handle errors eg.
to your ajax code add this:
error:function(e){
alert(e.statusText)// if you like alerts
console.log(e.statusText)// If you like console
}
You should also check your error logs. Assuming you use apache2 and linux
execute this in terminal:
tail -f /var/log/apache2/error.log
This gives you a very elaborate way to code. You also eliminate the problem of trial and error.

Script return blank just in jQuery AJAX

I've got very frustrating problem. I send AJAX request to PHP file and when I see Chrome Network Tools, it donť return any JSON. But when I try post the same data via POSTMAN tool in Chrome, it return right. When I open script normally, it return right. Just when I sen request via AJAXm it return nothing.
This is my PHP file: (I know it's functionally useless at this time, i need fix this error before it can do what I need)
$stav = 2;
$ret = array();
$name = query_r("select * from users where username = 'admin'");
$ret['stav']=$stav;
$json = json_encode($ret);
echo $json;
At line 3 must be problem, because when I put it out, it works. But function is 100% exist, 'cause when i put nonsense name of function, it write an error. DB query is also right, i tried it in phpMyAdmin console.
This is my AJAX request:
$("#loginForm").submit(function(e){
e.preventDefault();
$.ajax({
type: "POST",
url: "../admin/scripts/login.php",
data: $("#loginForm").serialize(),
dataType: "JSON",
success: function (vysledek){
if(vysledek.stav===1){
window.location.href("../index.php")
}
else if(vysledek.stav===2){
alertify.error('Špatné uživatelské jméno');
}
else if(vysledek.stav===3){
alertify.error('Špatné heslo');
}
},
error: function(vysledek){
alertify.error('Vyskytla se nějaká chyba');
}
});
});
How I wrote, if I open PHP file in browser, it echo {"stav":2}, when I try POSTman, it echo {"stav":2}. But when I run AJAX request, it makes nothing. I really don't know what is wrong.
EDIT
Firebug:
Here

can you please try with the following code
$("#loginForm").submit(function(e){
e.preventDefault();
$.ajax({
type: "POST",
url: "../admin/scripts/login.php",
data: $("#loginForm").serialize(),
dataType: "JSON",
success: function (vysledek){
if( parseInt(vysledek.stav) == 1 ){
window.location.href("../index.php")
}
else if( parseInt(vysledek.stav) == 2 ){
alertify.error('Špatné uživatelské jméno');
}
else if( parseInt(vysledek.stav) == 3 ){
alertify.error('Špatné heslo');
}
},
error: function(vysledek){
alertify.error('Vyskytla se nějaká chyba');
}
});
});

<?php
$stav = 2;
$ret = array();
$name = query_r("select * from users where username = 'admin'");
$ret['stav']=$stav;
$json = json_encode($ret);
print_r($json);
?>
Remember to parse JSON to the response
...
success: function (vysledek){
var vysledek = (vysledek);
if(vysledek.stav === 1){
window.location.href("../index.php")
}
...

Using ajax to send a JS variable, but how can I use PHP variables afterwards to my main file?

How can I use some PHP variables from the ajax-send.php to the index.php file? I use AJAX as shown below. Do I have to replace AJAX with something else?
index.php
$.ajax({
type: 'POST',
url: 'ajax-send.php',
data: { one: hash },
success: function(data) {
}
});
ajax-send.php
$token = $_POST['one'];
echo "ok"
$toINDEX = "use this in index.php"

Try this
Ajax
$.ajax({
type: 'POST',
url: 'ajax-send.php',
data: { one: hash },
success: function(data) {
var response = data;
//alert(data);To see what you have received from the server
}
});
PHP
if(isset($_POST['one'])){
$token = $_POST['one'];
echo "ok";
$toINDEX = "use this in index.php";
die();
}

In PHP just echo variable or json_encode array. In JS do the following:
var result = $.ajax({
url: this.fileUrl,
type: "POST",
data: data,
async: false,
dataType: 'json'
}).responseText;
Your vaiable is fully accessable.

take the variables in php sessions
//On page 1(ajax-send.php)
session_start();
$_SESSION['token'] = $_POST['one'];
//On page 2(index.php)
session_start();
$var_value = $_SESSION['token'];

You can simply echo the variable and then access it via javascript inside the success function.
But a better approach would be to json_encode the data. The beauty of this is that it will help you to pass multiple values/variables in a single echo. So
PHP
.
..
if(<all is okay>)
{
$toINDEX = "use this in index.php"
$data['result'] = 'ok';
$data['msg'] = $toINDEX;
$data['some_other_value'] = 'blah blah';
// notice how I'm able to pass three values using this approach
}
else
{
$data['result'] = 'notok';
}
echo json_encode($data);
Javascript
$.ajax({
type: 'POST',
url: 'ajax-send.php',
data: { one: hash },
dataType:'json',
success: function(data) {
if(data.result == 'ok')
{
console.log(data.msg);
console.log(data.some_other_value);
}
else
{
// something went wrong
}
}
});
The important thing to note here is dataType:'json' which tells the function to expect the returned data in json format.
EDIT:
As per you comment, you could do this
$toINDEX = "use this in index.php";
// now use the variable here itself
mysql_query("SELECT * FROM table WHERE column = '$toINDEX'");
.
.
if(<all is okay>)
{
$data['result'] = 'ok';
$data['msg'] = 'anything you would like to show the user';
$data['some_other_value'] = 'blah blah';
// notice how I'm able to pass three values using this approach
}
else
{
$data['result'] = 'notok';
}
echo json_encode($data);

Check all possible AJAX responses

I have an AJAX function which POST data to a PHP handler. I echo back either "success" or "failure" from PHP to determine if it was completed as intended. Unfortunately I am not used to JS/AJAX and have trouble finding documentation that answers my questions.
Do I need to JSON encode the response? I only check for .done() in my AJAX function, should I also check success and failed? My code inside of .done() which is just an alert box isn't working, despite the functionality in the PHP handler running without issue.
JS/AJAX:
<script type="text/javascript">
function powerSignal(device, signal)
{
var cfm = confirm("Do you wish to ___ the server?");
if (cfm==true)
{
$.ajax({ type: "POST", url: "https://domain.net/modules/power_functions.php", data: { device: device, 'power_signal': signal }}).done(function(result)
{
alert("success!");
});
}
}
</script>
PHP:
if ( isset($_POST["device"]) && isset($_POST["power_signal"]) )
{
$deviceid = $_POST["device"];
$signal = $_POST["power_signal"];
//API: Get Device Inventory
$url = 'http://domain.net/dp/api/set_device_power_status';
$fields = array('deviceid' => urlencode($deviceid), 'power_signal' => urlencode($signal));
$result = curl_get($url, $fields);
$json = json_decode($result);
$status = $json->{'status'};
if ($status == "success")
{
echo "success";
}
echo "failed";
}

the content of the result variable will be what the server sends back, you'll have to test it :
$.ajax({ type: "POST", url: "https://domain.net/modules/power_functions.php", data: { device: device, 'power_signal': signal }}).done(function(result)
{
if(result=='success'){
alert("success!");
}else{
alert("failure!");
});
To answer the comment below, here is how I do in my current project with a simple get request :
$.get( "/getResult/"+data, function( results ) {
$('.popin_content').html('<p>Vos documents ont bien été créés :</p><br/><ul><li>Plan PDF</li><li>Devis PDF</li></ul>');
});