groks URLs

cURL is very important tool for PHP programmers, we tends to do so many thing with using this tool. Posting data, imitating a form post and lot more, it's usage is countless. Some time back I came across situation where we have to post files to a 3rd party faxing service. I knew there are many possibilities but I didn't wanted to get into sockets and file stream to get this done, just wanted to post FILE in addition to rest of the post data.

// URL on which we have to post data
$url = "http://localhost/tutorials/post_action.php";
// Any other field you might want to catch
$post_data['name'] = "khan";
// File you want to upload/post
$post_data['file'] = "@c:/logs.log";
 
// Initialize cURL
$ch = curl_init();
// Set URL on which you want to post the Form and/or data
curl_setopt($ch, CURLOPT_URL, $url);
// Data+Files to be posted
curl_setopt($ch, CURLOPT_POSTFIELDS, $post_data);
// Pass TRUE or 1 if you want to wait for and catch the response against the request made
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
// For Debug mode; shows up any error encountered during the operation
curl_setopt($ch, CURLOPT_VERBOSE, 1);
// Execute the request
$response = curl_exec($ch);
 
// Just for debug: to see response
echo $response;

Above Code is the bare minimum required to post/upload file using CURL. As used in above example, it's not mandatory to use array index as "file". You can use anything required depending upon the requirement.

Posting multiple files is also easy, with the same code you can add multiple file upload using following lines:

$post_data['alian_error_log'] = "@c:/alian_app_error.log";
$post_data['myapp_error_log'] = "@c:/myapp_error.log";

Here @ is the key character, prefixing local file path with @ does all the trick.



cURL Post - as being received on posted URL

With PHP we can use cURL using libcurl extension for PHP. It comes bundled with most of the WAMP packages and available on almost all managed/web hosting environments.Similar Posts:

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Initially I tried that with file_get_contents function but it was just downloading 0KB file. Then it strike me that oh..! I can't use file_get_contents as it can't understand the HTTPS protocol here. So what could help me nothing else then our best friend CURL. file_get_contents and fopen kind of other functions works fine with any http web locations.

Here is the simple CURL file transfer function snippet which will copy file from any secure http location.

	/**
	 * Copy File from HTTPS/SSL location
	 *
	 * @param string $FromLocation
	 * @param string $ToLocation
	 * @return boolean
	 */
	function copySecureFile($FromLocation,$ToLocation,$VerifyPeer=false,$VerifyHost=true)
	{
		// Initialize CURL with providing full https URL of the file location
		$Channel = curl_init($FromLocation);
 
		// Open file handle at the location you want to copy the file: destination path at local drive
		$File = fopen ($ToLocation, "w");
 
		// Set CURL options
		curl_setopt($Channel, CURLOPT_FILE, $File);
 
		// We are not sending any headers
		curl_setopt($Channel, CURLOPT_HEADER, 0);
 
		// Disable PEER SSL Verification: If you are not running with SSL or if you don't have valid SSL
		curl_setopt($Channel, CURLOPT_SSL_VERIFYPEER, $VerifyPeer);
 
		// Disable HOST (the site you are sending request to) SSL Verification,
		// if Host can have certificate which is nvalid / expired / not signed by authorized CA.
		curl_setopt($Channel, CURLOPT_SSL_VERIFYHOST, $VerifyHost);
 
		// Execute CURL command
		curl_exec($Channel);
 
		// Close the CURL channel
		curl_close($Channel);
 
		// Close file handle
		fclose($File);
 
		// return true if file download is successfull
		return file_exists($ToLocation);
	}
	/**
	 *	This code don't work
	 *	echo file_get_contents("https://www.verisign.com/hp07/i/vlogo.gif");
	**/
	// Function Usage
	if(copySecureFile("https://www.verisign.com/hp07/i/vlogo.gif","c:/verisign_logo.gif"))
	{
		echo 'File transferred successfully.';
	}
	else
	{
		echo 'File transfer failed.';
	}

Please let me know if there are any other ways of doing that; other than this work around.Similar Posts:

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