I'm developing a certain PHP framework for WordPress, and I want to give my users the option to use composer to install it as a package, or to install it manually. If composer is used, then a psr-4 class autoloader handles everything. If not, then all files must be loaded manually during the framework's bootstrapping process.
Is there a safe way to check whether composer's autoloader is being used in a given WordPress environment?
Currently i'm using:
if( !class_exists('Composer\\Autoload\\ClassLoader') )
{
// Manually include files if composer is not used.
require_once 'some/files.php';
}
However, if in a given WordPress environment there is a plugin that uses composer internally, then the above if statement will return true even though other plugins have no access to it.
The solution, as it turns out, is quite simple. You need to create 2 different bootstrapping files, say manual-bootstrap.php and composer-bootstrap.php. Then add the following lines to composer.json:
"autoload": {
"files": ["composer-bootstrap.php"]
}
composer-bootstrap.php will only be called if composer is used to load the framework as a dependency. Users that want to load the framework manually will use manual-bootstrap.php instead.
if(class_exists("\Composer\Autoload\ClassLoader"))
{
// a composer autoload.php has already been included/required
}
Related
I want to install html-to-markdown without composer but I can't figure it out, with other libraries like Parsedown it worked just by using file location, but with html-to-markdown I don't know what I should use
This is the link for html-to-markdown
In your link there is a chapter How to use it with step by step instructions for installation.
Make sure to add require 'vendor/autoload.php'; to the top of your script, where you want to use the package.
First, use GitHub's "Code/ Download ZIP" option to get the code:
To figure out the requirements of an application meant to be installed with Composer, you need to inspect the composer.json file in the root directory:
The require key tells us the PHP extensions and third-party libraries needed:
"require": {
"php": "^7.2.5 || ^8.0",
"ext-dom": "*",
"ext-xml": "*"
},
In this case, the library is standalone, so you just need to verify your PHP installation meets the requirements. If it happened to need other packages, you'd have to repeat this for every package involved.
The autoload key tells us how the library locates and opens the files with class definitions:
"autoload": {
"psr-4": {
"League\\HTMLToMarkdown\\": "src/"
}
},
This library depends on Composer's PSR-4 autoloader implementation. We'll get back to this.
There may be other important information in the file, but in this particular case this is pretty much everything.
Regarding the autoloader... If your codebase already implements PSR-4, you just need to configure a new League\HTMLToMarkdown namespace and download the source code in the location expected by your autoloader, keeping the folder structure intact. Otherwise, I can think of a number of options, none of them particularly attractive:
Write your own autoloader.
Find a third-party PSR-4 autoloader.
Get a list of all relevant source PHP files and load them all manually:
$ find . -name '*.php'
./src/Environment.php
./src/Configuration.php
./src/Element.php
./src/ElementInterface.php
./src/PreConverterInterface.php
./src/HtmlConverterInterface.php
./src/ConfigurationAwareInterface.php
./src/Converter/TextConverter.php
./src/Converter/TableConverter.php
./src/Converter/ListItemConverter.php
./src/Converter/ListBlockConverter.php
./src/Converter/PreformattedConverter.php
./src/Converter/ConverterInterface.php
./src/Converter/DivConverter.php
./src/Converter/BlockquoteConverter.php
./src/Converter/HorizontalRuleConverter.php
./src/Converter/DefaultConverter.php
./src/Converter/CodeConverter.php
./src/Converter/ImageConverter.php
./src/Converter/HardBreakConverter.php
./src/Converter/ParagraphConverter.php
./src/Converter/EmphasisConverter.php
./src/Converter/CommentConverter.php
./src/Converter/HeaderConverter.php
./src/Converter/LinkConverter.php
./src/HtmlConverter.php
Make this into a list of require '...'; commands and play around with file order until you don't get errors.
I have module created in the basic project of yii2 and now i want to access or use that module another project/application of mine....
How can I achieve this.
please help me out here.
To use module in different apps there are 3 things you need.
The module must not be dependent on classes from core project. For any class that needs to be implemented by core project the module should define interface and depend on that interface instead of class itself.
The module should use different namespace than app and autoloader must know how to load classes from that namespace. (more about that later)
You have to add module in your config in same way you've added it in first project.
The points 1 and 3 are pretty much self-explaining. If are not sure how to add module in config see the yii2 guide.
Now back to the second point. While naive way of copying module over to second project would work it will turn maintaining the module into nightmare because each change would have to be done in each copy of module. So it's better to keep the code of module in one place and make it available for each project. There are multiple ways of doing that.
If you want to, you can turn your module into extension and make it publicly available through packagist as it was suggested by M. Eriksson in comments. After that you would simply add your extension through composer as any other dependency.
Composer also allows you to define and use private repositories if you don't want to publish your module at packagist. See composer documentation for more details.
The most trivial way is to simply put the code into separate folder outside of project. If you do that, you have to make sure that autoloaders in your projects are capable of finding the files locations to load classes. There are two options how to do that. In any case you will want to avoid conflicts with namespaces used by your project, that's why you need to use different namespace.
Let's assume that you've put your module files into folder /path/to/modules/myModule and all classes in your module belongs to namespace modules\myModule. You have to make sure that your webserver can access that folder and that it can run php scripts there.
First option is to use Yii's autoloader. That autoloader uses aliases to look for classes. If you add #modules alias and point it to /path/to/modules folder, the Yii autoloader will try to look for any class from modules\* namespace in /path/to/modules folder. You can add the alias in your config file (web.php, console.php or any other config file you use):
return [
// ...
'aliases' => [
'#modules' => '/path/to/modules',
// ... other aliases ...
],
];
The second option is to use project's composer.json file to set autoloader generated by composer to load your classes.
{
"autoload": {
"psr-4": {
"modules\\": "/path/to/modules"
}
}
}
You can find more info about this in composer's documentation.
Don't forget to run composer dump-autoload after you change autoload settings in your composer.json file to update the generated autoloader.
I've created a small command line tool in PHP and I've also packed that as a PHAR archive.
Next thing I did was publish my archive to packagist.org aka composer.
I can now install my PHAR package through composer like so:
composer global require acme/mypackage
This installs my package fine. And I'm able to run it through command as well.
So far so good, but here comes the problem I´m currently facing.
I have another project should use acme/mypackage. I want that project to reference a class that is packed into that PHAR. Something like this:
<?php
class SomeClass extends AcmeClass {
}
The problem is that the PHP code doesn't recognize the AcmeClass class. Makes sense, because it´s obviously "globally" installed somewhere on the system.
How do other libraries solve this issue? If I'm not mistaken then PHPUnit does something similar right?
How can I solve this issue?
You'll need to add a composer.json file to the root of your project:
The first (and often only) thing you specify in composer.json is the require key. You're simply telling Composer which packages your project depends on.
{
"require": {
"monolog/monolog": "1.0.*"
}
}
Next, you'll need to autoload your dependencies.
For libraries that specify autoload information, Composer generates a vendor/autoload.php file. You can simply include this file and you will get autoloading for free.
require 'vendor/autoload.php';
https://getcomposer.org/doc/01-basic-usage.md
How do I autoload a set of library API functions with a composer installed library?
I have a library with a function API used to interface the libraries internal objects and want composer to automatically load the API and make it available after install without requiring the end-developer to include a file.
Currently the library is loaded by just including the __init__.php and it includes the API functions and an autoloader if required.
Thanks!
Composer always will require the end-developer to include one file, which is vendor/autoload.php. You cannot make it easier that that.
But what you can do is make including __init__.php optional because the integration of Composer allows you to use that autoloader instead. This will also work for functions, which could not really be autoloaded - Composer offers to always include a file if being told so.
So in the end your Composer configuration of that API library would look like this:
{
"name": "yourvendorname/yourfancylibraryname",
"license": "any open source identifier",
"autoload": {
"psr-0": {
"Foo_Api": "src/files"
},
"classmap": [
"extra/folders_with_any_other_class_not_conforming_to_psr0_or_psr4"
],
"files": [
"functions/file_with_your_function_definitions.php"
]
}
}
I don't know about whether your classes conform to PSR-0 or even PSR-4, but if they do, you and everyone would benefit if you can declare the autoloader with these standards. If not: Classmap will help you.
Your function definition will be loaded by the file or files mentioned in "files".
You don't need your own autoloader anymore for Composer.
Of course you could also simply mention the old __init__.php as the file to be included in "files", but this would separate your library from all the other classes, would probably be less performant (Composer already has a very good autoloader - there is no need to have two of them) and would definitely exclude all your classes from being dumped into an even faster Composer classmap autoloader.
I've got some libraries loaded through composer, and I'm wondering if it's possible to add my own library in the /vendor map, and then to have the composer autoloader load it? The structure would be something like /vendor/mylibrary/ and then a namespace mylibrary.
Would this be possible? Also would it be possible to add a different map to the composer autoloader? Like for example /app/src/ and then to have it load all the classes in that folder? Or do I have to make my own loader for that?
Thanks
Reading the composer documentation:
You can even add your own code to the autoloader by adding an autoload field to composer.json.
{
"autoload": {
"psr-0": {"Acme": "src/"}
}
}
Composer will register a PSR-0 autoloader for the Acme namespace.
You define a mapping from namespaces to directories. The src directory would be in your project root, on the same level as vendor directory is. An example filename would be src/Acme/Foo.php containing an Acme\Foo class.
After adding the autoload field, you have to re-run install to
re-generate the vendor/autoload.php file.
So basically, you just need to follow PSR-0, and tell composer where to find your library, by adding that line to your composer.json
Yes.You can achieve it. Configure your composer.json file as following:
{
"autoload": {
"classmap": [ "classes" ]
}
Here classes is the name of the directory where you have all your application related classes.Vendor related class should be auto detected as well. Just add the following line to achieve both at the same time:
require 'vendor/autoload.php';
And you can use the namesapce to reference your class like the following:
use classes\Model\Article;
Yes, of course it is possible to add own libraries and you should feel highly encouraged to do so. If your library is available publicly, you can simply register it at packagist.org. If not, it's a bit more complicated, but not impossible.
If your project does not follow the PSR-0 standard, composer will create a classmap for you. A custom autoloader is not supported.
I'd recommend you to read the (really excellent) documentation about all this and come back, if you're running into problems.
http://getcomposer.org/doc/