cnpm安装时的奇怪问题

npm是node.js的包管理器，安装依赖包非常方便，但是因为是国外服务器，国内一般用cnpm，是淘宝维护的服务器，在国内安装包用cnpm比npm更快，最近用cnpm安装一个vue平台，遇到了cnpm安装时的奇怪问题，明明安装上了，结果文件找不到，安装了node.js 10,node.js 14,node.js 16都不行，第二天认真看文档，才发现问题，这问题一般人也不会留意，所以给大家说下。

下面是安装时错误日志：

npm install -g cnpm --registry=https://registry.npm.taobao.org
npm WARN deprecated har-validator@5.1.5: this library is no longer supported
npm WARN deprecated uuid@3.4.0: Please upgrade  to version 7 or higher.  Older versions may use Math.random() in certain circumstances, which is known to be problematic.  See https://v8.dev/blog/math-random for details.
npm WARN deprecated request@2.88.2: request has been deprecated, see https://github.com/request/request/issues/3142

下面是另外一次错误的日志：

.\npm install -g cnpm --registry=https://registry.npm.taobao.org
npm WARN deprecated uuid@3.4.0: Please upgrade  to version 7 or higher.  Older versions may use Math.random() in certain circumstances, which is known to be problematic.  See https://v8.dev/blog/math-random for details.
npm WARN deprecated request@2.88.2: request has been deprecated, see https://github.com/request/request/issues/3142
npm WARN deprecated har-validator@5.1.5: this library is no longer supported
D:\vueProject\nodejs\node_global\cnpm -> D:\vueProject\nodejs\node_global\node_modules\cnpm\bin\cnpm
npm WARN notsup Unsupported engine for open@8.4.0: wanted: {"node":">=12"} (current: {"node":"10.24.1","npm":"6.14.12"})
npm WARN notsup Not compatible with your version of node/npm: open@8.4.0
npm WARN notsup Unsupported engine for pacote@12.0.2: wanted: {"node":"^12.13.0 || ^14.15.0 || >=16"} (current: {"node":"10.24.1","npm":"6.14.12"})
npm WARN notsup Not compatible with your version of node/npm: pacote@12.0.2
npm WARN notsup Unsupported engine for npmlog@6.0.0: wanted: {"node":"^12.13.0 || ^14.15.0 || >=16"} (current: {"node":"10.24.1","npm":"6.14.12"})
npm WARN notsup Not compatible with your version of node/npm: npmlog@6.0.0
npm WARN notsup Unsupported engine for gauge@4.0.0: wanted: {"node":"^12.13.0 || ^14.15.0 || >=16"} (current: {"node":"10.24.1","npm":"6.14.12"})
npm WARN notsup Not compatible with your version of node/npm: gauge@4.0.0

上面应该是版本问题，下面是正确的日志：。

+ cnpm@7.1.0
added 54 packages from 12 contributors, removed 15 packages and updated 365 packages in 63.885s

成功了，但是安装的cnpm文件找不到，所以就奇怪了。表现如下图：

看文档里npm config set cache "D:\vueProject\nodejs\node_cache",这里盘符D和nodejs安装盘符E实际不对应，所以出了安装到不存在D盘目录下了，cache就是缓存的意思，会影响shell环境执行命令的硬盘位置，把set cache目录和实际安装目录一致，问题得到解决。

另外在控制台里，直接执行cnpm -v不行， 但是在ideal的控制台里可以，安装vue平台时，第一次cnpm install还没反应， 说包都有，不用安装，用npm install后，再用cnpm install就安装上依赖包了。

我经常用VS C++ C#开发，换个平台，就是换个思维，思维切换需要时间。很多开源文档都认为开发人员是熟手，比如这里的set cache有什么影响，安装时如何如何，文档没有说，这也是产生问题的一个重要原因。