无法将 composer 降级到版本 1，也无法在 Magento 2.4.0 上安装 elasticsuite

Question

I'm trying to install elasticsuite 2.10.1 on Magento 2.4 but I need to downgrade my composer to version 1 but I keep getting stuck.

When I try to downgrade to composer to version 1 with composer self-update --1

[Composer\Downloader\FilesystemException]
  Filesystem exception:
  Composer update failed: "/usr/local/bin/composer" could not be written.
  rename(/home/usr/.cache/composer/composer-temp7912166.phar,/usr/local/bin/composer): Permission denied

Adding sudo results in sudo: composer: command not found I've also installed composer globally and moved the .phar file to /usr/local/bin/composer

I've also ran composer update --no-plugins and it returns with the following:

  Problem 1
    - Root composer.json requires dealerdirect/phpcodesniffer-composer-installer ^0.5.0 -> satisfiable by dealerdirect/phpcodesniffer-composer-installer[v0.5.0].
    - dealerdirect/phpcodesniffer-composer-installer v0.5.0 requires composer-plugin-api ^1.0 -> found composer-plugin-api[2.1.0] but it does not match the constraint.
  Problem 2
    - laminas/laminas-dependency-plugin[1.0.0, ..., 1.0.4] require composer-plugin-api ^1.1 -> found composer-plugin-api[2.1.0] but it does not match the constraint.
    - magento/product-community-edition 2.4.0 requires laminas/laminas-dependency-plugin ^1.0 -> satisfiable by laminas/laminas-dependency-plugin[1.0.0, ..., 1.0.4].
    - Root composer.json requires magento/product-community-edition 2.4.0 -> satisfiable by magento/product-community-edition[2.4.0].

I've tried googling for answers and no luck for the last 2 hours, I'm out of ideas on how to resolve the problem

Answer 1

If you really want to use Composer v1 (which is deprecated and won't be around forever,), you need to run the downgrade with sudo in front to avoid permission problems.

Answer 2

The following works for me:

First, check the requirement for composer and php version here: https://devdocs.magento.com/guides/v2.4/install-gde/system-requirements.html

Remove the vendor folder

Assume you are using composer 2, for Magento 2.4.0 - 2.4.3-P2, run:

sudo composer self-update --1

Run the followings:

sudo yum install php php-{pear,cgi,common,ctype,curl,fileinfo,mbstring,gd,hash,iconv,sockets,sodium,tokenizer,xmlwriter,xsl,mysqlnd,gettext,bcmath,json,xml,fpm,intl,zip,imap,dom,simplexml,soap,libxml,openssl}

sudo composer install