Composer usage clarifications

In this repository I will use and explain composer main autoloadings: PSR-0, PSR-4, Classmap...

To see the modifications

composer status -v

Read composer.json install/update packages and its dependencies and update/create composer.lock

composer update

Read composer.json install/update only PHPUnit package and its dependencies and update/create composer.lock

composer update "phpunit/phpunit"

Will install the packages specified in composer.lock if not exists reads composer.json, install and write composer.lock

composer install

Instruction to remove a package

composer remove

Remove PHPUnit package and its dependencies

composer remove "phpunit/phpunit" --update-with-dependencies

Will add PHPUnit package into composer.json and install/update the package and its dependencies

composer require "phpunit/phpunit"

Creates a "classmap" mapping having each class to its file in a big array (vendor/composer/autoload_classmap.php)

composer dump-autoload --optimize

The instructions below defines to use stable versions following this order stable, dev or alpha packages searching to use the more stable (dev, stable, beta..)

"minimum-stability": "dev",
"prefer-stable" : true

Autoload of functions or classes by specifying file path (array is mandatory)

it includes in memory the code within the file (usually functions) so can be very nasty

"autoload": {
    "files": ["src/functions/list.php"]
}

Autoload of classes by specifying the classmap (composer dump-autoload is necessary everytime you had a new class). Array is mandatory

vendor/composer/autoload_classmap.php will content an array with Namespace\Package\Class => FILE_PATH_OF_CLASS

when invoking new Class() php will search within the classmap register

"autoload": {
    "classmap": ["lib/"],
}

Autoload by using PSR-0 standard.

WordWrapper is the Namespace from which will be performed the autoload eg. new \WordWrap/Class()

src is the parent directory of the location of the classes under namepace WordWrapper

Everytime a new Instance of WordWrap will be invoked, class file will be search within src/*

`composer install` will refresh vendor/composer/autoload_namespaces.php file which is read by vendor/composer/autoload_real.php

"autoload": {
    "psr-0": {
        "WordWrapper": ["src/"],
    }
}

Same thing but for a specific package of the namespace (classes of package Counter within the namespace Utils will be searched and loaded from src

When specifying a Namespace vendor/composer/autoload_namespaces.php will be update container Namespace\Package => DIRECTORY

"autoload": {
    "psr-0": {
        "Utils\\Counter": ["src/"]
    }
}

Autoload by using PSR-4 standard.

When requiring Class from namespace `Utils\Log' composer will search under src/Class.php

It is compatible with PSR-0 but doesn't oblige to have under src/ a tree src/Utils/Log like in PSR-0

"psr-4": {
    "Utils\\Log\\": ["src/"]
}

aurelienlair/composer