PHP cURL with SS validation - php

Question

I have some working cURL scripts but have been relying on the remote server for SS validation. I want to add some validation to our cURL scripts so that if they aren't filled out correctly the request won't get sent. I have client side JS validation, but want to duplicate with SS validation.
Here is an example of my cURL script:
<?php
$url = 'https://remoteserver.com/POST.svc/Foo';
$Field1 = $_POST["Field1"];
//other input data
$fields = array(
'Field1'=>urlencode($Field1),
//other input data
);
foreach($fields as $key=>$value) { $fields_string .= $key.'='.$value.'&'; }
$fields_string = rtrim($fields_string,'& ');
$ch = curl_init($url);
curl_setopt($ch, CURLOPT_HEADER, 0);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, $fields_string);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
$output = curl_exec($ch);
echo $output;
curl_close($ch);
?>
Can I just create an if/else statement like:
<?php
if(empty($_POST['Field1']))) {
echo "Error";
die();
} else {
$url = 'https://remoteserver.com/POST.svc/Foo';
$Field1 = $_POST["Field1"];
//other input data
$fields = array(
'Field1'=>urlencode($Field1),
//other input data
);
foreach($fields as $key=>$value) { $fields_string .= $key.'='.$value.'&'; }
$fields_string = rtrim($fields_string,'& ');
$ch = curl_init($url);
curl_setopt($ch, CURLOPT_HEADER, 0);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, $fields_string);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
$output = curl_exec($ch);
echo $output;
curl_close($ch);
}
I have ajax stuff that is displayed if the return is "Error". This can't be that easy, is it?
thx

Answer 1

Instead of just returning 'Error', why not return some useful stuff? A PHP structure such as
$request_status = array(
'error' => 1,
'error_msg' => 'Form was not completed properly'
'error_details' => array(
0 => 'Name field not completed',
1 => 'Invalid state specified',
2 => 'Password1 and Password 2 do not match'
)
)
echo json_encode($request_status);
would be of far more use. Your client-side ajax code can simply look for the 'error' parameter in there and either go "Hey, it worked!" or do further based on the error_details you supplied, such as highlighting the form fields that weren't completed correctly.
This also allows you to send back other types of error messages as well, such as saying "hey, the place we're CURLing your form to isn't responding" and the like.