Composer:
https://getcomposer.org/download/
linux服务器上执行下操作即可
sun@karat:~$ php -r "copy('https://getcomposer.org/installer', 'composer-setup.p hp');"
sun@karat:~$ php -r "if (hash_file('sha384', 'composer-setup.php') === '48e3236262b34d30969dca3c37281b3b4bbe3221bda826ac6 a9a62d6444cdb0dcd0615698a5cbe587c3f0fe57a54d8f5') { echo 'Installer verified'; } else { echo 'Installer corrupt'; unlink( 'composer-setup.php'); } echo PHP_EOL;"
Installer verified
sun@karat:~$ php composer-setup.php
All settings correct for using Composer
Downloading...
Composer (version 1.8.6) successfully installed to: /home/sun/composer.phar
Use it: php composer.phar
sun@karat:~$ php -r "unlink('composer-setup.php');"
sun@karat:~$ composer
Command 'composer' not found, but can be installed with:
sudo apt install composer
sun@karat:~$ php composer.phar
______
/ ____/___ ____ ___ ____ ____ ________ _____
/ / / __ \/ __ `__ \/ __ \/ __ \/ ___/ _ \/ ___/
/ /___/ /_/ / / / / / / /_/ / /_/ (__ ) __/ /
\____/\____/_/ /_/ /_/ .___/\____/____/\___/_/
/_/
Composer version 1.8.6 2019-06-11 15:03:05
Usage:
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.
-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 Opens the package's repository URL or homepage in your browser.
check-platform-reqs Check that platform requirements are satisfied.
clear-cache Clears composer's internal package cache.
clearcache Clears composer's internal package cache.
config Sets config options.
create-project Creates new project from a package into given directory.
depends Shows which packages cause the given package to be installed.
diagnose Diagnoses the system to identify common errors.
dump-autoload Dumps the autoloader.
dumpautoload Dumps the autoloader.
exec Executes a vendored binary/script.
global Allows running commands in the global composer dir ($COMPOSER_HOME).
help Displays help for a command
home Opens the package's repository URL or homepage in your browser.
i Installs the project dependencies from the composer.lock file if present, or falls back on the com poser.json.
info Shows information about packages.
init Creates a basic composer.json file in current directory.
install Installs the project dependencies from the composer.lock file if present, or falls back on the com poser.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 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 Runs the scripts defined in composer.json.
search Searches for packages.
self-update Updates composer.phar to the latest version.
selfupdate Updates composer.phar to the latest version.
show Shows information about packages.
status Shows a list of locally modified packages, for packages installed from source.
suggests Shows package suggestions.
u Upgrades your dependencies to the latest version according to composer.json, and updates the compo ser.lock file.
update Upgrades your dependencies to the latest version according to composer.json, and updates the compo ser.lock file.
upgrade Upgrades your dependencies to the latest version according to composer.json, and updates the compo ser.lock file.
validate Validates a composer.json and composer.lock.
why Shows which packages cause the given package to be installed.
why-not Shows which packages prevent the given package from being installed.
使用的时候,只是针对某个用户的。哪个用户安装的只能哪个用户使用,其它用户会出现:

为了解决多个用户(全局使用)。我们需要卸载了,重新安装,或者执行下面的命令:
cp composer.phar /usr/local/bin/composer
参考文档:
https://segmentfault.com/a/1190000006835510