所以我正在尝试在实现firebase云功能时在“functions”文件夹中安装firebase-admin模块（npm install firebase-admin --save)，但是这条错误信息会不断中断安装。它有事情要做没有找到“nopt.js”，我不知道如何修复它。是否与node / npm版本有关？有没有人有类似的问题并且能够解决它？
以下是错误消息：
npm ERR! Linux 3.13.0-129-generic
npm ERR! argv "/usr/bin/nodejs" "/usr/bin/npm" "install" "firebase-admin"
npm ERR! node v7.10.1
npm ERR! npm v4.2.0
npm ERR! path /vagrant/functions/node_modules/grpc/node_modules/node-pre-gyp/node_modules/nopt/bin/nopt.js
npm ERR! code ENOENT
npm ERR! errno -2
npm ERR! syscall chmod
npm ERR! enoent ENOENT: no such file or directory, chmod '/vagrant/functions/node_modules/grpc/node_modules/node-pre-gyp/node_modules/nopt/bin/nopt.js'
npm ERR! enoent ENOENT: no such file or directory, chmod '/vagrant/functions/node_modules/grpc/node_modules/node-pre-gyp/node_modules/nopt/bin/nopt.js'
npm ERR! enoent This is most likely not a problem with npm itself
npm ERR! enoent and is related to npm not being able to find a file.
npm ERR! enoent