本地环境

系统：windows10

laravel5.8.35

php7.2.0

composer已安装至最新版本1.9.1

扩展名称：laravel-queue-rabbitmq

问题描述

之前也是在社区看到的一个帖子，根据帖子的教程来安装扩展：composer require vladimir-yuldashev/laravel-queue-rabbitmq,然后就出现了问题：

Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - Conclusion: remove laravel/framework v5.8.35
    - Conclusion: don't install laravel/framework v5.8.35
    - vladimir-yuldashev/laravel-queue-rabbitmq v9.1.0 requires illuminate/queue ^6.0 -> satisfiable by illuminate/queue[6.x-dev, v6.0.0, v6.0.1, v6.0.2, v6.0.3, v6.0.4, v6.1.0, v6.2.0, v6.3.0, v6.4.1, v6.5.0, v6.5.1, v6.5.2].
    - vladimir-yuldashev/laravel-queue-rabbitmq v9.1.1 requires illuminate/queue ^6.0 -> satisfiable by illuminate/queue[6.x-dev, v6.0.0, v6.0.1, v6.0.2, v6.0.3, v6.0.4, v6.1.0, v6.2.0, v6.3.0, v6.4.1, v6.5.0, v6.5.1, v6.5.2].
    - vladimir-yuldashev/laravel-queue-rabbitmq v9.1.2 requires illuminate/queue ^6.0 -> satisfiable by illuminate/queue[6.x-dev, v6.0.0, v6.0.1, v6.0.2, v6.0.3, v6.0.4, v6.1.0, v6.2.0, v6.3.0, v6.4.1, v6.5.0, v6.5.1, v6.5.2].
    - don't install illuminate/queue 6.x-dev|don't install laravel/framework v5.8.35
    - don't install illuminate/queue v6.0.0|don't install laravel/framework v5.8.35
    - don't install illuminate/queue v6.0.1|don't install laravel/framework v5.8.35
    - don't install illuminate/queue v6.0.2|don't install laravel/framework v5.8.35
    - don't install illuminate/queue v6.0.3|don't install laravel/framework v5.8.35
    - don't install illuminate/queue v6.0.4|don't install laravel/framework v5.8.35
    - don't install illuminate/queue v6.1.0|don't install laravel/framework v5.8.35
    - don't install illuminate/queue v6.2.0|don't install laravel/framework v5.8.35
    - don't install illuminate/queue v6.3.0|don't install laravel/framework v5.8.35
    - don't install illuminate/queue v6.4.1|don't install laravel/framework v5.8.35
    - don't install illuminate/queue v6.5.0|don't install laravel/framework v5.8.35
    - don't install illuminate/queue v6.5.1|don't install laravel/framework v5.8.35
    - don't install illuminate/queue v6.5.2|don't install laravel/framework v5.8.35
    - Installation request for laravel/framework (locked at v5.8.35, required as 5.8.*) -> satisfiable by laravel/framework[v5.8.35].
    - Installation request for vladimir-yuldashev/laravel-queue-rabbitmq ^9.1 -> satisfiable by vladimir-yuldashev/laravel-queue-rabbitmq[v9.1.0, v9.1.1, v9.1.2].
Installation failed, reverting ./composer.json to its original content.

这段composer报错代码研究了一下安装vladimir-yuldashev/laravel-queue-rabbitmq没有指定版本时默认安装的是9.1版本，但是版本需要依赖illuminate/queue ^6.0这个扩展，之后到这个链接里去看看还真是需要这个扩展
扩展url

根据提示安装了这个扩展又报错了

     don't install illuminate/queue 6.x-dev|don't install laravel/framework v5.8.35

这个提示也是说这个扩展与框架版本不兼容，之后根据报错信息也有查过相关博客，有的提示升级composer,也有提示在输入命令后添加--ignore-platform-reqs，这些我都试过了，还是没有用。

很多博客都是直接composer require vladimir-yuldashev/laravel-queue-rabbitmq就直接成功了，估计那个时候安装的是laravel的最新版本，这个版本不匹配的问题得不到解决，然后我也安装了最新版本的laravel,再次执行这条命令时，毫无疑问，扩展安装成功了。

但是我很想知道，如果安装历史版本的laravel,要在想安装这类扩展时，那该怎么办呢，每个扩展在刚刚给出的链接里会存在依赖，但是laravel 的版本与这些扩展的版本之间的匹配该到哪里去找呢？