composer update 和 composer install 报错怎么办？

Question

I run composer install I got this error, telling me to use composer update

Loading composer repositories with package information
Installing dependencies (including require-dev) from lock file
Warning: The lock file is not up to date with the latest changes in composer.json. You may be getting outdated dependencies. Run update to update them.
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - Installation request for doctrine/inflector v1.3.0 -> satisfiable by doctrine/inflector[v1.3.0].
    - doctrine/inflector v1.3.0 requires php ^7.1 -> your PHP version (7.0.25) does not satisfy that requirement.
  Problem 2
    - Installation request for symfony/css-selector v4.0.3 -> satisfiable by symfony/css-selector[v4.0.3].
    - symfony/css-selector v4.0.3 requires php ^7.1.3 -> your PHP version (7.0.25) does not satisfy that requirement.
  Problem 3
    - Installation request for symfony/event-dispatcher v4.0.3 -> satisfiable by symfony/event-dispatcher[v4.0.3].
    - symfony/event-dispatcher v4.0.3 requires php ^7.1.3 -> your PHP version (7.0.25) does not satisfy that requirement.
  Problem 4
    - Installation request for doctrine/instantiator 1.1.0 -> satisfiable by doctrine/instantiator[1.1.0].
    - doctrine/instantiator 1.1.0 requires php ^7.1 -> your PHP version (7.0.25) does not satisfy that requirement.
  Problem 5
    - doctrine/inflector v1.3.0 requires php ^7.1 -> your PHP version (7.0.25) does not satisfy that requirement.
    - laravel/framework v5.5.32 requires doctrine/inflector ~1.1 -> satisfiable by doctrine/inflector[v1.3.0].
    - Installation request for laravel/framework v5.5.32 -> satisfiable by laravel/framework[v5.5.32].

I run composer update , I got this

Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - doctrine/dbal v2.6.3 requires php ^7.1 -> your PHP version (7.0.25) does not satisfy that requirement.
    - doctrine/dbal v2.6.2 requires php ^7.1 -> your PHP version (7.0.25) does not satisfy that requirement.
    - doctrine/dbal v2.6.1 requires php ^7.1 -> your PHP version (7.0.25) does not satisfy that requirement.
    - doctrine/dbal v2.6.0 requires php ^7.1 -> your PHP version (7.0.25) does not satisfy that requirement.
    - Installation request for doctrine/dbal ^2.6 -> satisfiable by doctrine/dbal[v2.6.0, v2.6.1, v2.6.2, v2.6.3].

Now what should I do?

This is what I have in composer.json

cat composer.json

{
    "name": "laravel/laravel",
    "description": "The Laravel Framework.",
    "keywords": ["framework", "laravel"],
    "license": "MIT",
    "type": "project",
    "require": {
        "php": ">=7.0.0",
        "anouar/paypalpayment": ">=3.0",
        "doctrine/dbal": "^2.6",
        "fideloper/proxy": "~3.3",
        "guzzlehttp/guzzle": "^6.3",
        "intervention/image": "^2.4",
        "laravel/framework": "5.5.*",
        "laravel/tinker": "~1.0",
        "spatie/laravel-newsletter": "^4.1",
        "srmklive/paypal": "~1.0"
    },
    "require-dev": {
        "filp/whoops": "~2.0",
        "fzaninotto/faker": "~1.4",
        "mockery/mockery": "~1.0",
        "phpunit/phpunit": "~6.0"
    },
    "autoload": {
        "classmap": [
            "database/seeds",
            "database/factories"
        ],
        "psr-4": {
            "App\\": "app/"
        },
        "files": ["app/Http/Helper.php"]
    },
    "autoload-dev": {
        "psr-4": {
            "Tests\\": "tests/"
        }
    },
    "extra": {
        "laravel": {
            "dont-discover": [
            ]
        }
    },
    "scripts": {
        "post-root-package-install": [
            "@php -r \"file_exists('.env') || copy('.env.example', '.env');\""
        ],
        "post-create-project-cmd": [
            "@php artisan key:generate"
        ],
        "post-autoload-dump": [
            "Illuminate\\Foundation\\ComposerScripts::postAutoloadDump",
            "@php artisan package:discover"
        ]
    },
    "config": {
        "preferred-install": "dist",
        "sort-packages": true,
        "optimize-autoloader": true
    }
} 

Answer 1

I faced the same issue few days ago I fixed it by faking the php version in my composer.json file [Not recommended] .

"config": {
        "preferred-install": "dist",
        "sort-packages": true,
        "optimize-autoloader": true,
        "platform" : {
            "php": "7.1"
        }
    }

For more details read this

Or you can execute composer update/install commands with --ignore-platform-reqs flag as shown below

composer update --ignore-platform-reqs

Answer 2

You need to install them one by one. In Ubuntu you can use apt for it.

For example:

sudo apt search inflector

You will see a package related to you version of PHP. Then just do normal installation of it via:

sudo apt install php-symfony-inflector

And so on...

Answer 3

You have a few options to tackle this, but all of them are highly dependant on the environment you are trying to run the command.

Let's assume that the composer file is from a 3rd piece of code, if they set the minimum php version it is ok to assume they did so for a reason. I would not try and circumvent this error by faking the version or changing the requirements.

If you have access, you could:

1. update the php version on your environment
2. run this in an docker container that has the required versions for your project.
3. install a php-fpm version that will match what the requirement is.

With the update option (1) you have to make sure that any other projects that run on the environment don't have compatibility issues with the version you may be updating to. The docker option (2) is in my opinion the safest one, but you'll have to do some reading on how to set it up (assuming your runing on linux: https://docs.docker.com/engine/install/ ). and the last one (3) requires you to setup a php-fpm and then make sure that your virtual host runs with the correct php to make sure you are running on the correct version ( https://www.digitalocean.com/community/tutorials/how-to-run-multiple-php-versions-on-one-server-using-apache-and-php-fpm-on-ubuntu-18-04 )