file_get_contents() returning empty string - php

Question

I am having the weirdest, head splitting issue ever. The real issue is I'm getting a SOAP error SOAP-ERROR: Parsing WSDL: Couldn't load from 'some website' : failed to load external entity
In the past it was caused by the host not responding, bad URL, etc. But today I have no problem connecting to the host.
I'm using Symfony to run the API. I stripped ALL of the soap code from the API, created a simple test.php file and ran it from the command line on the exact server the API is running on, and it worked perfectly!
So I went back to the Symfony, flushed the cache. Still not working.
Next I decided to test the simplest methods I could and slapped 'file_get_contents('the url to the WSDL')` at the very top of the service that's making this SOAP call. It returns an empty string. No errors in the error log.
Next I tried moving that to the Controller. Still an empty string.
I tried file_get_contents('https://google.com'). Still, empty string no matter where in the Controller or Service I stick it. But, if on that same server I run a PHP script from the command line, it works no problem.
I don't even know where to begin showing you my code. Because it doesn't matter if file_get_contents() is in the controller, an entity, or the services it's using. Every time it returns an empty string.
As a side note, this is a development server. Which is an exact mirror of production (they just made an image of the production server). The whole API works fine in production and also on my local dev environment and in other environments it's been deployed to. So I'm entirely lost on why it's just this server, and just this particular application.
Any help is appreciated.
==
Update 1
As suggested by a friend I checked allow_url_fopen in both the cli php -i and apache phpinfo() and in both cases it's set to On
==
Update 2
As Pedro suggested I ran a cURL test in the controller of the API. And that worked, it retrieved the contents of the WDSL, and of course Google.
However, it doesn't solve my root problem with SOAP not retrieving the contents of a URL. Nor the obvious file_get_contents() not working. Does the PHP SOAP client use file_get_contents() to retrieve WSDLs?
==
Update 3
For those curious this is where the code is failing. I have to omit a lot of the class because it contains information specific to my company.
<?php
class Carrier implements CarrierInterface
{
//...omitted code
private function getSoapClient($wsdl)
{
// This line is what fails.
return new \SoapClient( $wsdl , array('trace' => true));
}
//...omitted code
public function quote(QuoteInterface $quote)
{
//Get the Soap Client
$client = $this->getSoapClient($this->quoteWSDL);
// The rest of the SOAP CALL
return $quote;
}
}
But in short, $this->quoteWSDL is just a URL, and yes it has a the correct value I've checked. But it fails when trying to construct the SOAP client stating SOAP-ERROR: Parsing WSDL: Couldn't load from '<url>' : failed to load external entity
==
Update 4 (with Kinda Solution)
Restarting apache fixed everything. I'm not sure why I didn't just ask the SysAdmin to do that sooner. That's like IT 101 right there. Thanks for your help. But now I'm curious why this was an issue to begin with. Weird.

Answer 1

My guess is that allow_url_fopen is disabled.
To enable it, you'll have to set allow_url_fopen=1 on php.ini.
Restart the Apache server to reload the configuration.
Have you considered using curl? Here's an example:
$url = "http://google.com";
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);
$contents = curl_exec($ch);
curl_close($ch);
PS: For future users: Make sure you read the comments below.