Error while retrieving content from external website

Question

I have a code that searches a content inside an external site in the G1 case, it works perfectly but brings me with the page CSS so I can not customize to leave in the pattern of my site, searching found another that shows me the data without formatting giving me freedom to manipulated in the best possible way, but when I request an extensive content it does not open me giving me the following error.

Notice: Undefined offset: 2 in C:\xampp\htdocs\ruralrio\blog\2.php on line 15

my code and this

<?php

$url_base = "http://g1.globo.com/economia/noticia/2015/07/justica-paulista-suspende-multa-de-r-3-milhoes-ao-mcdonalds.html";
$texto = preg_replace("/((\r\n|\t)+|\s{2,})/", "",
file_get_contents($url_base));

preg_match('/<title>(.*)<\/title>/i', stripslashes($texto), $titulo);
preg_match('/<h1 class="entry-title">(.*)<\/h1>/i', stripslashes($texto), $titulomateria);
preg_match('/<h2>(.*)<\/h2>/i', stripslashes($texto), $titulomateria2);
preg_match('/<div class="materia-conteudo entry-content" id="materia-letra">(.*)<\/div>/i', stripslashes($texto), $titulomateria3);

echo strip_tags($titulo[1]) . "<br /><br />";
echo strip_tags($titulomateria[1]) . "<br /><br />";
echo strip_tags($titulomateria2[1]) . "<br /><br />";
echo strip_tags($titulomateria3[2]) . "<br /><br />";

?>

Answer 1

Possible problems:

1. file_get_contents is not enabled to access external urls, to fix use:

   Edit php.ini and change it allow_url_fopen=0 for allow_url_fopen=1 (http://php.net/manual/en/filesystem.configuration.php)

2. file_get_contents requires context with user-agent, so it is necessary to do something like:

   $headers = array(
       'Accept-language: pt-br',
       'User-Agent: ' . $_SERVER['HTTP_USER_AGENT']
   );
   
   $opts = array(
       'http'=>array(
           'method' => 'GET',
           'header' => implode(PHP_EOL, $headers)
       )
   );
   
   $context = stream_context_create($opts);
   
   $texto = file_get_contents('http://g1.globo.com/economia/noticia/2015/07/justica-paulista-suspende-multa-de-r-3-milhoes-ao-mcdonalds.html', false, $context);
   

3. Instead of using preg_match try using DOM, for example:

   $doc = new DOMDocument();
   
   //Modifica o estado
   $libxml_previous_state = libxml_use_internal_errors(true);
   
   //Faz um parse na string
   $doc->loadHTML($texto);
   
   //Limpa os erros
   libxml_clear_errors();
   
   //Restaura ao normal
   libxml_use_internal_errors($libxml_previous_state);
   

   _{Source: https://stackoverflow.com/a/17559716/1518921}

   And then use methods like getelementsbytagname, getelementbyid and Domxpath (to facilitate)

The final code should look something like:

<?php
$headers = array(
    'Accept-language: pt-br',
    'User-Agent: ' . $_SERVER['HTTP_USER_AGENT']
);

$opts = array(
    'http'=>array(
        'method' => 'GET',
        'header' => implode(PHP_EOL, $headers)
    )
);

$context = stream_context_create($opts);

$texto = file_get_contents('http://g1.globo.com/economia/noticia/2015/07/justica-paulista-suspende-multa-de-r-3-milhoes-ao-mcdonalds.html', false, $context);

$doc = new DOMDocument();

// modify state
$libxml_previous_state = libxml_use_internal_errors(true);

// parse
$doc->loadHTML($texto);

// handle errors
libxml_clear_errors();

// restore
libxml_use_internal_errors($libxml_previous_state);

$tmp = $doc->getElementsByTagName('title');

foreach ($tmp as $value) {
    echo 'Titulo:', $value->nodeValue, '<br>';
}

$xpath = new DOMXPath($doc);

$tmp = $xpath->query('//h1[contains(@class,"entry")]');

foreach ($tmp as $value) {
    echo 'h1.entry:', $value->nodeValue, '<br>';
}

$tmp = $doc->getElementsByTagName('h2');

foreach ($tmp as $value) {
    echo 'h2:', $value->nodeValue, '<br>';
}

$tmp = $doc->getElementById('materia-letra')->getElementsByTagName('div');

foreach ($tmp as $value) {
    echo '#materia-letra:', $value->nodeValue, '<br>';
}