PHP Error: Permission denied in Unknown at line 0 [FIX]

I was setting up a quick PHP test in my home directory today, but when I tried to load my file (http://localhost/~david/test.php) I encountered a strange error:

Warning: Unknown: failed to open stream: Permission denied in Unknown on line 0 Fatal error: Unknown: Failed opening required '/home/david/public_html/test.php' (include_path='.:/usr/share/php5/PEAR:/usr/share/php5') in Unknown on line 0

My code was pretty simple - no "include" or "require" statements anywhere, and perfectly valid syntax. This puzzled me for some time - it appeared as if PHP was trying to "require" my test file in itself. As it turns out, that wasn't too far from the truth.

This error was simply caused by Apache (and therefore PHP) not having read permissions to my PHP file. So it could tell that the file was there (otherwise I would get a 404 error), but when PHP tried to open the file for reading it failed, due to my file permissions (in this case, 007). To fix the problem, I simply had to run:

chmod 777 /home/david/test.php

After this my PHP code ran perfectly. It's worth knowing that this kind of error can occur - it might save a lot of Googling like I had to do!

Note: Normally I wouldn't change the permissions on a PHP file to 777 (everyone has full access, including write). However, in this case it was just a simple test page running on localhost, so I wasn't too worried about security.

Symfony 'String could not be parsed as XML'

I was receiving this error on my symfony project (using the sfWhoIsOnline plugin):

[28-Aug-2010 21:50:54] PHP Fatal error:  Uncaught exception 'Exception' with message 'String could not be parsed as XML' in /home/xxxxxxx/plugins/sfWhoIsOnlinePlugin/lib/sfWhoIsOnlineUserFacade.class.php:38
Stack trace:
#0 /home/xxxxxxx/plugins/sfWhoIsOnlinePlugin/lib/sfWhoIsOnlineUserFacade.class.php(38): SimpleXMLElement->__construct('')
#1 /home/xxxxxxx/plugins/sfWhoIsOnlinePlugin/lib/filter/sfWhoIsOnlineFilter.class.php(14): sfWhoIsOnlineUserFacade::registerUser(Object(myUser))
#2 /home/xxxxxxx/cache/frontend/prod/config/config_core_compile.yml.php(1026): sfWhoIsOnlineFilter->execute(Object(sfFilterChain))
#3 /home/xxxxxxx/plugins/sfDoctrineGuardPlugin/lib/sfGuardRememberMeFilter.class.php(56): sfFilterChain->execute()
#4 /home/xxxxxxx/cache/frontend/prod/config/config_core_compile.yml.php(1026): sfGuardRememberMeFilter->execute(Object(sfFilterChain))
#5 /home/xxxxxxx/cache/frontend/prod/config/config_core_compile.yml.php(990): sfFilterChain->execute()
#6 /home/xxxxxxx/cache/frontend/prod/config/config_core_compile.yml.php(1026): sfRenderingFilt in /home/xxxxxxx/plugins/sfWhoIsOnlinePlugin/lib/sfWhoIsOnlineUserFacade.class.php on line 38
[29-Aug-2010 00:06:48] String could not be parsed as XML
[29-Aug-2010 02:14:47] String could not be parsed as XML

Turns out, SimpleXMLElement can't handle empty strings or badly encoded documents well. As a patch of sorts, I replaced the code at line 38 in the sfWhoIsOnlineUserFacade class with the following lines (original lines in bold):

/* Begin Hack to fix error 'String could not be parsed as XML' */
try {
  $xml = new SimpleXMLElement($xmlString);    // <-- Original line 38   

$instance->fromXml($xml);                // <-- Original line 39
} catch (Exception $e) {
  sfContext::getInstance()->getLogger()->crit('sfWhoIsOnline failed to create SimpleXMLElement');
  sfContext::getInstance()->getLogger()->crit('xmlString: '.$xmlString);
}
/* End Hack */

References:
http://drupal.org/node/541892
http://weierophinney.net/matthew/archives/111-mbstring-comes-to-the-rescue.html
http://www.google.com/search?hl=en&q=String+could+not+be+parsed+as+XML&aq=f&aqi=&aql=&oq=&gs_rfai=
http://ketarin.canneverbe.com/forum/viewtopic.php?id=384

Install phploc on openSuSE 11.3 [HOWTO]

Once you've got PEAR installed, run these commands (as root):

pear channel-discover pear.phpunit.de
pear channel-discover components.ez.no
pear install phpunit/phploc


At first I was getting errors:

phpunit/File_Iterator requires PEAR Installer (version >= 1.9.1), installed version is 1.9.0
phpunit/phploc requires package "phpunit/File_Iterator" (version >= 1.2.0)
No valid packages found
install failed


But running:

pear upgrade-all


fixed all the errors.

Symfony / sfGuardUser: MySQL errno: 150 Failing Query "ALTER TABLE sf_guard_user......."

I've been trying to link up my symfony project (using Doctrine) to sfGuardPlugin with profiles. However, when trying to rebuild the schema and insert sql, I encountered the following error:

SQLSTATE[HY000]: General error: 1005 Can't create table 'phoenix.#sql-740_d7' (errno: 150). Failing Query: "ALTER TABLE sf_guard_user_profile ADD CONSTRAINT sf_guard_user_profile_user_id_sf_guard_user_id FOREIGN KEY (user_id) REFERENCES sf_guard_user(id)". Failing Query: ALTER TABLE sf_guard_user_profile ADD CONSTRAINT sf_guard_user_profile_user_id_sf_guard_user_id FOREIGN KEY (user_id) REFERENCES sf_guard_user(id)


This isn't an incredibly useful error message. Turns out that it's to do with the way MySQL handles cascading constraints. To cut a long story short, there's more info in the links posted below, but basically you need to remember that "type: integer" does not mean it will be stored as INTEGER in MySQL. As a matter of fact, "type: integer" in a schema.yml file translates into a "BIGINT(20)" in MySQL - which means when you add a constraint to a normal INTEGER field, it fails.

To store an integer value in schema.yml, use "type: integer(4)". This will translate into a type of INTEGER in MySQL.

Explained in a comment I found:

Something you might be interested in, that took me quarter an hour. integer(11) in schema.yml does not result in int(11) in MySQL, but instead you have to write integer(4) in your schema.yml. integer integer int/serial integer(1) tinyint smallint/serial integer(2) smallint smallint/serial integer(3) mediumint int/serial integer(4) int int/serial integer(5) bigint bigint/bigserial However, in my case integer without a number resulted in BIGINT.

More info:
http://trac.symfony-project.org/wiki/sfGuardPluginExtraDocumentation
http://mirmodynamics.com/post/2009/04/02/SQLSTATE%5BHY000%5D%3A-General-error%3A-1005-Can-t-create-table-*-%28errno%3A-150%29 (especially see the last comment)
http://bytes.com/topic/mysql/answers/865699-cant-create-table-errno-150-foreign-key-constraints

PHP: How to (Code) to check if a Windows file / folder name is valid.

Two PHP functions to check a string to see if it is a valid windows filename. The first simply checks the string, the second function will replace all occurrences of the invalid characters with a blank.


/**
* Checks to see if a filename is valid for Windows
* Invalid characters are: < > : " / \ | ? *
* Returns false if invalid characters found, else true
*/
function isValidFilename($filename)
{
if(preg_match('/[<>:"\/\\\|?*]/i', $filename))
{
//Invalid characters found
setDebug("Filename '$filename' contained invalid characters.");
return false;
} else {
//No invalid characters, must be valid filename
setDebug("Filename '$filename' contained no invalid characters.");
return true;
}
}

/**
* Removes all invalid characters from a Windows filename.
* Invalid characters are: < > : " / \ | ? *
* Returns the (possibly) modified string
*/
function fixFilename($filename)
{
setDebug("Filename to fix: {$filename}");
$newFilename = preg_replace('/[<>:"\/\\\|?*]/i', "", $filename);
setDebug("Fixed filename: {$newFilename}");
return $newFilename;
}


FIX: PHP MSSQL odbc_num_rows() returns -1

Running MSSQL with PHP  on Windows sometimes returns -1 for the function odbc_num_rows() even when there are rows in the result. This function fixes the problem:

 function best_odbc_num_rows($result,$currentRow=0)  {
   $numRecords = 0;
  odbc_fetch_row($result, 0);
  while (odbc_fetch_row($result))
  {
    $numRecords++;
  }
  odbc_fetch_row($result, $currentRow);
  return $numRecords;
}

How To Enable Curl in PHP on Linux

 To enable PHP Curl support on Linux with apache 2:

$ sudo apt-get install php5-curl

Or do it manually (compiling sources):
http://au2.php.net/manual/en/curl.installation.php
http://curl.haxx.se/libcurl/php/install.html
http://www.wallpaperama.com/forums/how-to-find-out-if-php-is-compiled-with-curl-extension-installed-enabled-t1576.html