Steps to install Composer ubuntu 20.4

 

sudo apt-get remove composer

• Download the installer to the current directory

• php -r "copy('https://getcomposer.org/installer', 'composer-setup.php');"

  
   
• Verify the installer SHA-384, which you can also https://getcomposer.org/download/
  

  php -r "if (hash_file('sha384', 'composer-setup.php') === '55ce33d7678c5a611085589f1f3ddf8b3c52d662cd01d4ba75c0ee0459970c2200a51f492d557530c71c15d8dba01eae') { echo 'Installer verified'; } else { echo 'Installer corrupt'; unlink('composer-setup.php'); } echo PHP_EOL;"

• Run the installer

• php composer-setup.php 

  Remove the installer

  
  

php -r "unlink('composer-setup.php');"

 sudo apt install composer

Refderences:

https://getcomposer.org/download/ 

sudo composer self-update 

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composer install error

1. sudo apt install wget php-cli php-zip unzip
2. php -r "copy('https://getcomposer.org/installer', 'composer-setup.php');"
3. HASH="$(wget -q -O - https://composer.github.io/installer.sig)"
4. php -r "if (hash_file('SHA384', 'composer-setup.php') === '$HASH') { echo 'Installer verified'; } else { echo 'Installer corrupt'; unlink('composer-setup.php'); } echo PHP_EOL;"

Installer verified

5. sudo php composer-setup.php --install-dir=/usr/local/bin --filename=composer

All settings correct for using Composer
Downloading...
Composer (version 2.0.14) successfully installed to: 
/usr/local/bin/composer
Use it: php /usr/local/bin/composer