您忘记安装所需的库

composer require league/flysystem-aws-s3-v3

祝你好运

适用于laravel 8

composer require --with-all-dependencies league/flysystem-aws-s3-v3 "^1.0"

我用

composer require guzzlehttp/psr7 "1.8.1"

首先从版本2.0.0降级，因为wassdk软件包还不支持版本2.0.0..然后

composer require league/flysystem-aws-s3-v3 "~1.0" --update-with-all-dependencies

根据Laravel文件：

https://laravel.com/docs/8.x/filesystem

你需要这种依赖

composer require --with-all-dependencies league/flysystem-aws-s3-v3 "^1.0"

@localheinz当我执行部署时，我运行：编写器安装
但在heroku中，软件包从具有heroku Jmeter 板的控制台安装它们。
但当我想添加或删除软件包league/flysystem-aws-s3-v3时，出现以下消息：

未安装列出的更新程序包。忽略。

所以我认为这中间有一个缓存，因为对我来说一切都很好。

{
"name": "laravel/laravel",
"description": "The Laravel Framework.",
"keywords": ["framework", "laravel"],
"license": "MIT",
"type": "project",
"require": {
    "php": ">=5.6.4",
    "barryvdh/laravel-debugbar": "^2.4",
    "fzaninotto/faker": "^1.6",
    "laravel/framework": "5.4.*",
    "laravel/socialite": "^3.0",
    "laravel/tinker": "~1.0",
    "unisharp/laravel-ckeditor": "^4.6",
    "league/flysystem-aws-s3-v3": "~1.0"
},
"require-dev": {
    "mockery/mockery": "0.9.*"
},
"autoload": {
    "classmap": [
        "database"
    ],
    "psr-4": {
        "App\\": "app/"
    }
},
"autoload-dev": {
    "psr-4": {
        "Tests\\": "tests/"
    }
},
"scripts": {
    "post-root-package-install": [
        "php -r \"file_exists('.env') || copy('.env.example', '.env');\""
    ],
    "post-create-project-cmd": [
        "php artisan key:generate"
    ],
    "post-install-cmd": [
        "Illuminate\\Foundation\\ComposerScripts::postInstall",
        "php artisan optimize"
    ],
    "post-update-cmd": [
        "Illuminate\\Foundation\\ComposerScripts::postUpdate",
        "php artisan optimize"
    ]           
},
"config": {
    "preferred-install": "dist",
    "sort-packages": true,
    "optimize-autoloader": true
}
  }

对我来说，我也遇到了同样的问题，尝试了很多解决方案，但都没有效果。最后，我发现flysystem-aws-s3-v2在composer.lock中，尽管我使用的是flysystem-aws-s3-v3命令：composer require league/flysystem-aws-s3-v3，它不会更改composer.lock中的任何内容，因此我所做的是删除vendor文件夹和composer.lock文件，并运行composer install，这为我解决了问题。

我的情况有点困难，我必须升级几个相关的依赖项才能让它启动和运行。主要是我把aws/aws-sdk-php升级到了composer在我运行时提到的版本：composer require --with-all-dependencies league/flysystem-aws-s3-v3 "^1.0" .

Laravel 9溶液

composer require league/flysystem-aws-s3-v3 "^3.0"