Hi I am using CakePHP and there are some Vendor files I need to add to the autoloading. Is this the correct method:
In the bootstrap.php, I have the following code:
function __autoload($className){
$classFile = '../vendors/phprtf/' . str_replace('_', '/', $className) . '.php';
// check if file exists
if(file_exists($classFile)) {
require $classFile;
}
}
The PHPRTFLite has a lot of class files under various sub directories. So listing all of them is not a good option.
It seems to be working for now.
You should use spl_autoload_register() for the flexibility it offers.
If your code has an existing __autoload function then this function
must be explicitly registered on the __autoload stack. This is because
spl_autoload_register() will effectively replace the engine cache for
the __autoload function by either spl_autoload() or
spl_autoload_call().
If there must be multiple autoload functions, spl_autoload_register()
allows for this. It effectively creates a queue of autoload functions,
and runs through each of them in the order they are defined. By
contrast, __autoload() may only be defined once.
Related
I am learning advanced PHP standards and trying to implement new and useful methods. Earlier I was using __autoload just to escape including multiple files on each page, but recently I have seen a tip on __autoload manual
spl_autoload_register() provides a more flexible alternative for
autoloading classes. For this reason, using __autoload() is
discouraged and may be deprecated or removed in the future.
but I really can't figure out how to implement spl_autoload and spl_autoload_register
spl_autoload_register() allows you to register multiple functions (or static methods from your own Autoload class) that PHP will put into a stack/queue and call sequentially when a "new Class" is declared.
So for example:
spl_autoload_register('myAutoloader');
function myAutoloader($className)
{
$path = '/path/to/class/';
include $path.$className.'.php';
}
//-------------------------------------
$myClass = new MyClass();
In the example above, "MyClass" is the name of the class that you are trying to instantiate, PHP passes this name as a string to spl_autoload_register(), which allows you to pick up the variable and use it to "include" the appropriate class/file. As a result you don't specifically need to include that class via an include/require statement...
Just simply call the class you want to instantiate like in the example above, and since you registered a function (via spl_autoload_register()) of your own that will figure out where all your class are located, PHP will use that function.
The benefit of using spl_autoload_register() is that unlike __autoload() you don't need to implement an autoload function in every file that you create. spl_autoload_register() also allows you to register multiple autoload functions to speed up autoloading and make it even easier.
Example:
spl_autoload_register('MyAutoloader::ClassLoader');
spl_autoload_register('MyAutoloader::LibraryLoader');
spl_autoload_register('MyAutoloader::HelperLoader');
spl_autoload_register('MyAutoloader::DatabaseLoader');
class MyAutoloader
{
public static function ClassLoader($className)
{
//your loading logic here
}
public static function LibraryLoader($className)
{
//your loading logic here
}
With regards to spl_autoload, the manual states:
This function is intended to be used as a default implementation for __autoload(). If nothing else is specified and spl_autoload_register() is called without any parameters then this functions will be used for any later call to __autoload().
In more practical terms, if all your files are located in a single directory and your application uses not only .php files, but custom configuration files with .inc extensions for example, then one strategy you could use would be to add your directory containing all files to PHP's include path (via set_include_path()).
And since you require your configuration files as well, you would use spl_autoload_extensions() to list the extensions that you want PHP to look for.
Example:
set_include_path(get_include_path().PATH_SEPARATOR.'path/to/my/directory/');
spl_autoload_extensions('.php, .inc');
spl_autoload_register();
Since spl_autoload is the default implementation of the __autoload() magic method, PHP will call spl_autoload when you try and instantiate a new class.
Since PHP 5.3, you can use spl_autoload_register() with namespaces, which means that you can organize your project and autoload your php classes without any require or include and without redefining an __autoload() function.
To demonstrate this behaviour, just create a file called index.php :
<?php
spl_autoload_register();
var_dump(new Main\Application);
Then create a folder named Main located right next to the index.php file. Finally, creates a file called Application.php located into Main and paste the following code into it :
<?php namespace Main;
class Application{}
Here is the way I do use Autoload.
In the given example I wanto to load classes form 3 diferent directories.
function namespaceAutoload($rawClass){
$class = str_replace('\\', DIRECTORY_SEPARATOR, $rawClass);
$possiblePaths[] = '..\sys\class\file.php';
$possiblePaths[] = '..\sys\class\lib\file.php';
$possiblePaths[] = '..\sys\class\class.file.inc.php';
foreach ($possiblePaths as $templatePath) {
$path = str_replace(["\\", "file"], [DIRECTORY_SEPARATOR, $class], $templatePath);
if (file_exists($path)) {
require_once "$path";
break;
}
} spl_autoload_register("namespaceAutoload");
I the given example, the PHP will look for the namespace\class in these three directories using these three different filename formats.
Working with OOP in php,
spl_autoload_register() lets you register multiple function, classes, trait etc to your php script.
Heres a use case on /test folder structure
/.htaccess
/index.php
/autoload.php
/controller/test.php
Inside autoload.php file:
spl_autoload_register(function ($classname) {
include_once dirname(__FILE__) . "/" . str_replace("\\", "/", $classname) . '.php';
});
Inside .htaccess
DirectoryIndex index.php
# php_value auto_prepend_file
php_value auto_prepend_file "/xampp/htdocs/test/autoload.php"
Inside controller/test.php
namespace controller;
class test {
public static function sayHello () {
echo "hello";
}
}
Inside index.php
use controller/test;
echo test::sayHello();
The autoload.php can be included or like the example above prepend on all script. It loads the class test and lets you use it directly without having to include the test.php script by pathname.
After a little bit of research and have been unable to locate a solution to my problem. I am utilizing an API that is namespaces that I downloaded via composer. The API has it dependences that I allow composer to manage and autoload for me. Separate from this I have about 10 classes that I have autoloaded with utilizing php's spl_autoload_register. Recently, I started mixing the classes to finish up part a project and the whole thing has gone to crap. My custom classes cannot use the composer classes and visa versa. Is there a method I can use to autoload classes that are in two separate folders and that are loaded with two separate outloader.
Here is the code that I currently use. The vender/autoload.php is no different then your typical composer autoloader. Thanks for any assistance.
require 'vendor/autoload.php';
require 'functions/general.php';
require 'include/mailgun.php';
function my_autoloader($class) {
require 'classes/' . $class . '.php';
}
spl_autoload_register('my_autoloader');
Well, actually composer utilizes spl_autoload_register, so answer is 'yes', they can. The autoloading mechanism is supported by autoloader stack - basically, if class didn't appear in runtime after one autoloader has been run, next one is used, until stack runs out of autoloaders and PHP reports an error about a class it can't find. Every spl_autoload_register call basically adds new autoloader, so there may be plenty of autoloaders in memory. The main point of this story is autoloader that can't load class does nothing, the autoloading block of code simply ends with no action taken so next autoloader may take responsibility of class loading. The only thing you need to implement is check in your autoloader that it can handle current class loading (checking that file exists before requiring it is enough, though you should think about possible directory nesting in case of namespaces), and everything should work smooth in future:
function my_autoloader($class) {
$path = sprintf('classes/%s.php', $class);
if (file_exists($path)) {
require 'classes/' . $class . '.php';
}
}
After further research due to ideas that the both #Etki and #Sarah Wilson gave me I came up with the following solution. Thank You both for your input.
require 'vendor/autoload.php';
require 'functions/general.php';
require 'include/mailgun.php';
function autoLoader ($class) {
if (file_exists(__DIR__.'/classes/'.$class.'.php')) {
require __DIR__.'/classes/'.$class.'.php';
}
}
spl_autoload_register('autoLoader');
Hint: I added the __DIR__ to the beginning of the file paths inside the autoLoader function.
If this is for a small project where you are including files from two or three folders you can use a simple if statement.
function my_autoloader($class) {
if(file_exists('functions/'.$class.'.php')){
require 'functions/'$class.'.php';
} else if(file_exists('vendor/'.$class.'.php')){
require 'vendor/'.$class.'.php';
} //add more as needed
}
spl_autoload_register('my_autoloader');
For larger applications, I recommend naming your classes files and your classes for what they are or do, and have them in a specific folder by their names Example: controllers/userController.php for userController class functions/generalFunctions.php generalFunctions class then you can check the names and if it has controller then you include it from the controllers folders. Create an array within the my_autoloader function or in a separate file like.
loadMap.php
return [
'controller' => 'path/to/controllers/',
'function' => 'path/to/functions/',
'helper' => 'path/to/helpers',
'etc' => 'path/to/etc/'
]
filewithautoloadfunction.php
function my_autoloader($class){
$loadMap = require 'path/to/loadMap.php';
foreach($loadMap as $key => $path){
if(stripos($key, $class){
require_once $path.$class.'.php';
}
}
}
spl_autoload_register('my_autoloader');
I'm actually trying to create a MVC framework for my own, however I'm having troubles with the Autoload. It's not a problem actually, but I'd like to ask the gurus, how are they using the spl_autoload_register function when there are different directories.
Lets say we have the following directories:
Controllers
Libs
Models
Each folder contains different classes, like:
Controllers:
Main.php
File.php
About.php
Libs:
Main.php
Front_controller.php
Models:
Index.php
File.php
Login.php
You can notice that some file names might be found with the same name in different directories. Okay, so this is what I've tried so far:
spl_autoload_register(function ($class) {
$pathContorllers = 'Controllers/' . $class . '.php';
$pathLibs = 'Libs/' . $class . '.php';
$pathModels = 'Models/' . $class . '.php';
if (file_exists($pathContorllers)) {
require_once $pathContorllers;
} elseif (file_exists($pathLibs)) {
require_once $pathLibs;
} elseif (file_exists($pathModels )) {
require_once $pathModels ;
}
});
It is working well, however I'm sure that there is another way to make everything simpler. Can anyone suggest me how can I make this code better or simpler / what are gurus using in this situation?
For the purpose of keeping individuals who may come across this answer from obtaining out-of-date information I have updated it in regards to the latest PSR autoloading standards. The original answer has been maintained for historical purposes and for those who are only interested in the PSR-0 autoloader.
Updated Answer
The PHP-FIG has officially deprecated the PSR-0 standard in favor of the alternative autoloader, PSR-4. Although the two are similar in some aspects they are also very different in others. (E.g.: the handling of underscores in class names.)
You may be thinking to yourself -- "I use PSR-0 now and it works fine." The truth of the matter is that PSR-0 will still work fine for certain projects. This is especially true when backwards compatibility with a package that doesn't use namespaces is concerned. PSR-0 is still a decent autoloading principle, but it has its own shortcomings.
Of course, if there is one thing that is a constant with programming, it is that code eventually changes and programming techniques continue to evolve. You can do yourself a favor today by preparing yourself for tomorrow. Therefore, if you are just starting a project or are trying to port a project to a newer version of PHP that can use namespaces, you should seriously consider using the PSR-4 autoloader.
It is also worth noting that if you are developing a project that does not use namespaces then PSR-4 does not apply to you. In this case PSR-0 or your own custom autoloader applies.
Original Answer
If you want to go with namespaces in your classes, then the PSR-0 route is a pretty good way to autoload. Basically your namespace represents you directory structure and classes can be loaded based on a convention.
If the PSR-0 method doesn't meet all your needs (or doesn't play nice with existing code) you can still add more functions with spl_autoload_register and PHP will go through them one by one in an attempt to load classes.
Example usage:
First thing is first, if you aren't familiar with namespaces in PHP then you will benefit from checking out the PHP manual on the subject. They can be a bit confusing at first, but their benefits are worth the initial confusion.
So I said that PSR-0 works by associating your namespaces with your directory structure. Let's use your directories for an example. You have in your root folder (wherever it may be) the following:
Project directory: <- Let's call this directory "MyProject"
Controllers:
Main.php
File.php
About.php
Libs:
Main.php
Front_controller.php
Models:
Index.php
File.php
Login.php
index.php <- Let's say this is your entry point file, this is where you will be autoloading stuff from.
Now let's take a look at your controller Main.php. Two things to keep in mind is that the class name needs to be the name of the file and the namespace for that class is the directory path to that file. So Main.php should look something like this:
<?php
namespace MyProject\Controllers;
class Main {
//Field vars, contructor, methods, etc. all go here.
}
?>
You would do the same thing for your your Login model
<?php
namespace MyProject\Models;
class Login {
//Field vars, contructor, methods, etc. all go here.
}
?>
Now in your index.php file (out in the root directory - MyProject) you would make your call to the spl_autoload_register and give it the PSR-0 autoloader.
spl_autoload_register( function ($className) {
$className = ltrim($className, '\\');
$fileName = '';
$namespace = '';
if ($lastNsPos = strrpos($className, '\\')) {
$namespace = substr($className, 0, $lastNsPos);
$className = substr($className, $lastNsPos + 1);
$fileName = str_replace('\\', DIRECTORY_SEPARATOR, $namespace) . DIRECTORY_SEPARATOR;
}
$fileName .= str_replace('_', DIRECTORY_SEPARATOR, $className) . '.php';
require $fileName;
});
//Now you can make your call to your objects without a bunch of include/require statements
$main = new \MyProject\Controllers\Main(); //Instantiates your 'Main' controller
$login = new \MyProject\Models\Login(); //Instantiates your 'Login' model
Hopefully that helps make better sense of it, and again, if you don't want to use namespaces you can always just keep adding closures into the SPL autoload stack. You can have 10 different autoloaders in there if you want and PHP will go through them one by one (in the order you defined them) using each function to try and load a class. However, a couple convention based autoloaders is a bit cleaner and more of a preferred method. Also keep in mind that the autoloader translates both namespace separators \ and underscores _ as a directory separator. So your Front_controller.php would not autoload as you would expect.
The code below will help. But I'll advice you check on Namespaces.
spl_autoload_register ( function ($class) {
$sources = array("Controllers/$class.php", "Lib/$class.php ", "Models/$class.php " );
foreach ($sources as $source) {
if (file_exists($source)) {
require_once $source;
}
}
});
I use this simple autoloader code:
function __autoload( $class_name ) { include 'class.' . $class_name . '.php'; }
and I make this call new SDB();
SDB actually inherits from SDBOne which I never include...yet the auto-loader loads it.
This means it knows to load modules nested / included in other modules.
So from the looks of it I never need to require or include anything if I use the auto-loader.
However, if I use a stand alone module where there is no auto-loader, I then need to include the class it inherits from.
Should I use
require,
require_once,
include,
include_once.
I would guess to go with require_once because I want an error not a warning...plus when I use the code with the autoloader I don't want it loaded twice.
Basically I have 2 types of use for SDB : one with the autoloader present and one with out.
Reference
http://php.net/manual/en/language.oop5.autoload.php
You are correct, require_once would be the correct way to include a parent class or dependent class in one file. That way if its included multiple times, the require_once prevents errors that would arise from redeclaring a class.
The autoloader is autoloading SDBOne automatically because it needs that class defined before it can extend SDB from it. The same thing is happening to autoload the parent class on demand as happens when you try to load the inherited class.
Also, you should consider switching to spl_autoload_register so that your code will work well with other code that may use an autoloader. The SPL autoloader supports multiple autoloaders and creates a stack in the order they are registered. This way if the first autoloader doesn't satisfy the requirement, it keeps trying subsequently registered autoloaders until the class is loaded or cannot be found.
Another note on preventing errors, you may want to change your autoload function as follows:
function __autoload( $class_name ) {
$file = 'class.' . $class_name . '.php';
if (file_exists($file)) {
include $file;
}
}
Because if the class being autoloaded doesn't exist, you will get errors about including a non-existent file. This is especially important when using spl_autoload_register; you don't want your autoloader to emit unnecessary warnings about missing files if another autoloader will be ultimately responsible for loading the class in question.
Hope that helps.
According to the PCR-0 proposal, all the autoloader needs is autoload() function. Zend has a few autoloading classes
Zend_Loader()
Zend_Loader_Autoloader()
Zend_Loader_Autoloader_Resource()
Zend_Loader_Autoloader_Interface()
I'm guessing it has all these classes because it's a framework, so it needs to load its own classes, as well as library classes for any libraries that the developer may add and which don't have their own autoloader.
I have a library (normal library, not a framework). Right now it doesn't have an autoloader so I use Zend's Zend_Loader_Autoloader_Resource ->addResourceType(). If I write an autoloader for it, which autoloader will be used: Zend's or the library? and do I have to implement an autoloader as complex as Zend's or a simple one like the PCR-0 example.
What happens in these cases
both framework and library have their own autoloader
framework has autoloader, but the library doesn't
framework has NO autoloader, and library has
I'd suggest sticking to direct path->class mapping and implementing your own autoloader like this:
class MyLib_Autoloader
{
public function __construct() {
spl_autoload_register(array($this, 'autoload'));
}
public function autoload($className)
{
if (substr($className, 0, 6) == 'MyLib_') {
include dirname(__FILE__) . DIRECTORY_SEPARATOR . '..' . DIRECTORY_SEPARATOR strtr($className, '_', DIRECTORY_SEPARATOR) . '.php';
return true;
}
return false;
}
}
This will check if the class is from your namespace and load the file. Assumes your autoloader is in /some/path/MyLib/ -> the include path will be /some/path/MyLib/../MyLib/ClassName.php. You can also add more logic to strip the initial MyLib from the class name and get rid of that '..'.
Make sure to use only require. It's faster and the autoload function is not called more than once for each classname! :) No need to include_once/require_once/etc. Go with the fastest.
Usage is as simple as:
include '/some/path/MyLib/Autploader.php';
$loader = new MyLib_Autoloader();
The main question is : who/how will your library be used ?
If that is by you only, then use Zend's autoloader, this will save you time. You don't need to reinvent the wheel.
If you have to make you library public and used on different projects, then that may be a problem because it will force the users of your library to have Zend Framework too. So in that case, either you make your own autoloader, either you pick one of a framework/library but include it in your library (watch out for the licenses).
Now regarding the utilisation of the autoloaders : only the autoloaders that are registered will be called. If you have your own autoloader, but you didn't mention how to setup it in your documentation, the users of your code will never think of set it up, and then it won't be used.
So the basic answer is to say : use many autoloaders, register them all, and they will be all called and everything will work fine. But that may lead to conflicts, because one autoloader will try to load something that is supposed to be handled by another autoloader, so you have to be careful with that, and not abuse of them.