How to use -data curl in PHP

Question

With curl from linux bash I can download a webpages passing some variables

curl --data "var1=val1&var2=val2&var3=&var4=val4&btnSubmit=btnName" https://<url> -o "<fileToSave>"

I need to do the same things but to get the full html code of that page into a php variable. I'm trying with this:

<?php $ch = curl_init();


$post_data = array (
    "var1" => "val1",
    "var2" => "val2",
    "var3" => "",
    "var4" => "val4",
    "btnSubmit" => "btnName"
);

curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true); 
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, $post_data);

$response = curl_exec($ch);
?>

The problem is that from bash I can retrieve the html pages and save it with this code my $response value is empty.

What's wrong?

Answer 1

Use http_build_query() over the $post_data , otherwise curl will assume to POST multipart/form-data posting based on the Array Data type(that's why it is not working for you).

curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($post_data));

http_build_query() converts the array into key1=value1&key2=value2 formated string with automatic urlencode() .

Answer 2

Seems like you are connecting to a HTTPs URL. You should enable this cURL parameter.

curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);