Problem
An HTTPS problem was encountered while studying the hacker News API. Because all the hacker News APIs are accessed through the encrypted HTTPS protocol, unlike the normal HTTP protocol, when using PHP functions file_get_contents()
to get the data provided in the API, there is an error
The code used is this:
<?php
$data = file_get_contents ("/http://blog.it985.com/");
? >
When running the code above, you are encountering the following error message:
PHP warning:file_get_contents (): Unable to find the wrapper "https" –did your forget to enable it when you configured PHP ?
Why is there such a mistake?
After a search on the internet, found that a lot of people have encountered such a mistake, the problem is very direct, because in the PHP configuration file does not open a parameter, in My computer is/apache/bin/php.ini in ;extension=php_openssl.dll
this item, need to remove the semicolon before.
You can use the following script to check the configuration of your PHP environment:
<?php
$w = Stream_get_wrappers ();
Echo ' OpenSSL: ', extension_loaded (' OpenSSL ')? ' Yes ': ' no ', ' \ n ';
Echo ' http wrapper: ', In_array (' http ', $w)? ' Yes ': ' no ', ' \ n ';
Echo ' https wrapper: ', In_array (' https ', $w)? ' Yes ': ' no ', ' \ n ';
Echo ' wrappers: ', Var_dump ($w);
Running the script fragment above, the result on my machine is:
<?php
openssl:no
http wrapper:yes
https wrapper:no
Wrappers:array (a) {
[0]=>
String (3) "PHP"
[1]=>
string (4) "File"
[2]=>
string (4) "Glob"
[3]=>
string (4) "Data"
[4]=>
string (4) "http"
[5]=>
string (3) "FTP"
[6]=>
string (3) " Zip "
[7]=>
string" compress.zlib "
[8]=>
string" Compress.bzip2
[9]=>
string (4) "Phar"
}
Alternative scenarios
Finding errors, correcting errors, is simple and difficult to correct when you find an error. I originally wanted to put this script method on the remote host, but I couldn't modify the remote host's PHP configuration, and as a result, I couldn't use this option, but we couldn't hang in a tree, this road doesn't work, see if there's another way.
Another function that I often use to crawl content in PHP is curl
that it is file_get_contents()
more powerful and provides a lot of optional parameters. For problems accessing HTTPS content, the configuration parameters we need to use CURL
are:
curl_setopt ($ch, Curlopt_ssl_verifypeer, FALSE);
You can see from the semantics that it is ignoring/skipping SSL security validation. Perhaps this is not a good practice, but for the ordinary scene, this is enough.
Here is a function that leverages the Curl
encapsulation to access HTTPS content:
function Gethttps ($url) {
$ch = Curl_init ();
curl_setopt ($ch, Curlopt_ssl_verifypeer, FALSE);
curl_setopt ($ch, Curlopt_header, false);
curl_setopt ($ch, curlopt_followlocation, true);
curl_setopt ($ch, Curlopt_url, $url);
curl_setopt ($ch, Curlopt_referer, $url);
curl_setopt ($ch, Curlopt_returntransfer, TRUE);
$result = curl_exec ($ch);
Curl_close ($ch);
return $result;
}
Summarize
The above is PHP crawl HTTPS content and error handling of all content, I hope the content of this article for everyone to learn or use PHP can help, if there is doubt you can message exchange.