damonparker.org

MySQL Error Function Wrapper for PHP

damonp — Tue, 08 Feb 2011 00:01:32 +0000

I was recently asked to supply some development and debugging functionality to a web application built for a client. The following function can be configured to popup for only your IP, and gives an error message containing the SQL, line number and file for easy debugging of the error.

I like this function over my current hobbled together debug kit because the display is positioned top center of the page via CSS no matter where the error occurs. Plus it includes a hide button to hide the majority of the error output and remove button to remove the error display altogether.

function mysql_error_wrapper($q, $sql='', $line='', $file='') {
if($_SERVER['REMOTE_ADDR'] != 'YOUR LOCAL IP') return false;
?>

echo '

';
echo '\'sqlerror\')">hide - remove';
echo '

MySQL error: '.mysql_errno().' Line: #'.$line.' '.basename($file).'

';

echo '

';

        

        echo wordwrap(mysql_error());

        

        if($sql != '')  {

            echo 'SQL
'.wordwrap($sql);

        }



        if($line != '') {

            echo 'Line
'.$line;

        }

        

        if($file != '') {

            echo 'File
'.$file;

        }

                    

        echo '

';
echo '

';

}
?>

Usage example:

$sql = "YOUR SQL STATEMENT";
$q = mysql_query($sql, $db);
if(!$q) mysql_error_wrapper($q, $sql, __LINE__, __FILE__);
?>

Download a Remote File Using PHP and cURL

damonp — Thu, 03 Feb 2011 17:02:51 +0000

Some years back, I posted a function to download a remote file with PHP. The function was useful when cURL and other URL/remote file functions had been disabled for security reasons. At the time, cURL on PHP was relatively new and many hosting setups didn’t include the cURL PHP module.

Support for PHP-cURL is pretty standard now, so I thought I’d update the the function to use cURL now. In addition, the function no longer returns a buffer containing the file data which can cause memory issues in PHP when dealing with large files. Pass this updated function a remote URL and local file path and it will download the file and save it to the local path.

This function is useful to retrieve remote images, download HTML pages and download any remote files.

function http_get_file($remote_url, $local_file) {

$fp = fopen($local_file, 'w');

$cp = curl_init($remote_url);
curl_setopt($cp, CURLOPT_FILE, $fp);

$buffer = curl_exec($cp);

curl_close($cp);
fclose($fp);

return true;
}
?>

Hardcode WordPress Site URL

damonp — Tue, 11 Jan 2011 20:13:16 +0000

I’m working on a project for mobile devices and need to be able to setup the same WordPress install on both the .mobi and the .com domain. This snippet lets you hardcode the URL and home configurables in wp_config.php. We use one setup of configurables for the .mobi side and another set for the .com.

define('WP_HOME','http://example.com');
define('WP_SITEURL','http://example.com');

Thanks to the WordPress Codex.

Linux Grep Tips

damonp — Wed, 17 Nov 2010 21:04:33 +0000

Search for red OR green:

grep 'red\|green' files

Search for searchtext at the beginning of a line in files:

grep '^searchtext' files

Search for searchtext at the end of a line in files:

grep 'searchtext$' files

Search files for blank lines:

grep '^$' files

Search files for US formatted phone numbers (###-###-####):

grep '[0-9][0-9][0-9]-[0-9][0-9][0-9]-[0-9][0-9][0-9][0-9]' files

or:

grep '[0-9]\{3\}-[0-9]\{3\}-[0-9]\{4\}' files

Search for e-commerce or ecommerce in files:

grep e-*commerce files

Search for searchtext case-insenstively in files:

grep -i searchtext files

Search for searchtext at the beginning of a line in files:

grep '^searchtext' files

Chain two grep commands together for more advanced searches. Search for lines in files that contain both partial_name and function:

grep partial_name files | grep function

That one is great for searching source directories for a function definition when you can’t remember the completely function name.

HTML Image Caption

damonp — Thu, 11 Nov 2010 04:53:09 +0000

id="image-caption"> style="border: 1px solid black; float: right; margin: 0 0 10px 10px;" src="/images/imagename.jpg" border="0" alt="" width="175" height="132" />
class="caption">HTML Image Caption

Cannot find terminfo entry for ‘xterm-256color’

damonp — Wed, 10 Nov 2010 14:16:14 +0000

Check if you have the terminfo file installed.

find /lib/terminfo /usr/share/terminfo -name "*256*"

No results? Install ncurses-term.

sudo apt-get install ncurses-term

Debugging Wifi Connectivity and Routing

damonp — Fri, 11 Jun 2010 21:33:32 +0000

Sometimes wifi connectivity issues can be massaged a little by getting a little pushy with it… turn your internal airport card off. Leave it off for a minute then turn it back on and see if by forcing it to attempt to re-connect to your local network. Oftentimes this will clear up minor issues.

Check your routing tables:

netstat -nr

Get just the default route:

netstat -nr | grep default

In action:

[root@howie ~]$ netstat -nr | grep default
5:default 192.168.1.1 UGSc 11 5 en1

Cloudy Costa Rican Sunset

damonp — Tue, 01 Jun 2010 23:21:02 +0000

Looks like it’s going to rain tonight.

iPhone Goodreader and Email

damonp — Tue, 27 Apr 2010 23:19:30 +0000

Goodreader is simply the best PDF / document reader around for the iPad. It allows you to download documents in a dozen different ways and store them locally on your device. Another great feature is the ability to directly email these as attachments from inside Goodreader.

Unfortunately, said feature is limited somewhat by the limitations of the device. Trying to compose a message in the tiny popup box is a pain… especially when the box starts jumping around on every keypress as the tiny window tries to alternately flow the text and show the attachment.

Good thing there is a fix for any app using the iPhone/iPad built-in mail functionality. Simply type something in the text field to put something in the message body. I use a couple of returns or set the To: address. Then close the message. When the app asks if you would like to save the draft, hit Yes and the message along with attachment will be saved in your Mail Drafts folder. You can retrieve it there any time to finish writing your message and send the attachment.

If you fail to type something in the new message pop up, the mail app wont ask you if you want to save the draft. It will exit and trash your message.

Enable Sendmail for PHP mail() in OSX

damonp — Thu, 25 Feb 2010 22:05:41 +0000

Since this didn’t dawn on me for thirty minutes while I pursued other avenues…

In /etc/hostconfig add/edit a line like:

MAILSERVER=-YES-

Note to self: Look for more OSX server administration clients.