使用composer安装库而不更新composer.json上当前库的版本

Question

So today I tried to install bootstrap with the composer via composer.json. I added twbs/bootstrap in my require list at the composer.json file in my project map and runned the command

$ composer update

It was succesfully downloaded and with a few adjustments to my code and command line I can use it now in my base:html.twig file.

Unfortunately, the composer updated also my version of symfony from 2.7 to 2.8. Is there any option that I update/download bootstrap without updating my version number of Symfony, doctrine etc with the composer? My code of composer.json:

{
"name": "symfony/framework-standard-edition",
"license": "MIT",
"type": "project",
"description": "The \"Symfony Standard Edition\" distribution",
"autoload": {
    "psr-4": { "": "src/", "SymfonyStandard\\": "app/" }
},
"require": {
    "php": ">=5.3.3",
    "symfony/symfony": "~2.7@beta",
    "doctrine/orm": "~2.2,>=2.2.3,<2.5",
    "doctrine/dbal": "<2.5",
    "doctrine/doctrine-bundle": "~1.4",
    "symfony/assetic-bundle": "~2.3",
    "symfony/swiftmailer-bundle": "~2.3",
    "symfony/monolog-bundle": "~2.4",
    "sensio/distribution-bundle": "~3.0,>=3.0.12",
    "sensio/framework-extra-bundle": "~3.0,>=3.0.2",
    "incenteev/composer-parameter-handler": "~2.0",
    "friendsofsymfony/user-bundle": "~1.3",
    "twbs/bootstrap": "3.2.*",
    "components/jquery": "1.9.*" 
},
"require-dev": {
    "sensio/generator-bundle": "~2.3"
},
"scripts": {
    "post-root-package-install": [
        "SymfonyStandard\\Composer::hookRootPackageInstall"
    ],
    "post-install-cmd": [
        "Incenteev\\ParameterHandler\\ScriptHandler::buildParameters",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::buildBootstrap",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::clearCache",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installAssets",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installRequirementsFile",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::removeSymfonyStandardFiles",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::prepareDeploymentTarget"
    ],
    "post-update-cmd": [
        "Incenteev\\ParameterHandler\\ScriptHandler::buildParameters",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::buildBootstrap",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::clearCache",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installAssets",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installRequirementsFile",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::removeSymfonyStandardFiles",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::prepareDeploymentTarget"
    ]
},
"config": {
    "bin-dir": "bin"
},
"extra": {
    "symfony-app-dir": "app",
    "symfony-web-dir": "web",
    "symfony-assets-install": "relative",
    "incenteev-parameters": {
        "file": "app/config/parameters.yml"
    },
    "branch-alias": {
        "dev-master": "2.7-dev"
    }
}
}

Answer 1

You can require the library:

$composer require twbs/bootstrap

This will put the library in a compatible version with the libraries you have.

If you also don't want to update Symfony in the future, you can add an extra version to the string:

"require": {
  "symfony/symfony": "~2.7.0@beta",
},

This will make composer understand you don't want to upgrade to 2.8 or highter versions.

Source: https://getcomposer.org/doc/articles/versions.md#next-significant-release-operators