composer

TLDR

Interactively create a composer.json file

$ composer init

Add a package as a dependency for this project, adding an entry to composer.json

$ composer require [user/package]

Install all the dependencies in this project's composer.json and create composer.lock

$ composer install

Uninstall a package from this project, removing it as a dependency from composer.json and composer.lock

$ composer remove [user/package]

Update all the dependencies in this project's composer.json and note new versions in composer.lock file

$ composer update

Update only composer.lock after updating composer.json manually

$ composer update --lock

Learn more about why a dependency can't be installed

$ composer why-not [user/package]

Update composer to its latest version

$ composer self-update

SYNOPSIS

composer command [options] [arguments]

OPTIONS

-h, --help: Display this help message
-q, --quiet: Do not output any message
-V, --version: Display this application version
--ansi: Force ANSI output
--no-ansi: Disable ANSI output
-n, --no-interaction: Do not ask any interactive question
--profile: Display timing and memory usage information
--no-plugins: Whether to disable plugins.
-d, --working-dir=WORKING-DIR: If specified, use the given directory as working directory.
--no-cache: Prevent use of the cache
-v|vv|vvv, --verbose: Increase the verbosity of messages: 1 for normal output, 2 for more verbose output and 3 for debug

Available commands:

about: Shows the short information about Composer.
archive: Creates an archive of this composer package.
browse: [home] Opens the package's repository URL or homepage in your browser.
check-platform-reqs: Check that platform requirements are satisfied.
clear-cache: [clearcache|cc] Clears composer's internal package cache.
config: Sets config options.
create-project: Creates new project from a package into given directory.
depends: [why] Shows which packages cause the given package to be installed.
diagnose: Diagnoses the system to identify common errors.
dump-autoload: [dumpautoload] Dumps the autoloader.
exec: Executes a vendored binary/script.
fund: Discover how to help fund the maintenance of your dependencies.
global: Allows running commands in the global composer dir ($COMPOSER_HOME).
help: Displays help for a command
init: Creates a basic composer.json file in current directory.
install: [i] Installs the project dependencies from the composer.lock file if present, or falls back on the composer.json.
licenses: Shows information about licenses of dependencies.
list: Lists commands
outdated: Shows a list of installed packages that have updates available, including their latest version.
prohibits: [why-not] Shows which packages prevent the given package from being installed.
remove: Removes a package from the require or require-dev.
require: Adds required packages to your composer.json and installs them.
run-script: [run] Runs the scripts defined in composer.json.
search: Searches for packages.
show: [info] Shows information about packages.
status: Shows a list of locally modified packages.
suggests: Shows package suggestions.
update: [u|upgrade] Upgrades your dependencies to the latest version according to composer.json, and updates the composer.lock file.
validate: Validates a composer.json and composer.lock.