Unable to install genie acs on ubantu

i was installing genieacs on using https://github.com/genieacs/genieacs/wiki/Installation-Guide-Ubuntu-16.04 on ubantu 16 but getting error after

sudo npm install libxmljs

npm WARN enoent ENOENT: no such file or directory, open ‘/root/package.json’
npm WARN root No description
npm WARN root No repository field.
npm WARN root No README data
npm WARN root No license field.

then if i ignore this and go to

sudo npm install -g genieacs

npm ERR! Linux 4.4.0-165-generic
npm ERR! argv “/usr/bin/nodejs” “/usr/bin/npm” “install” “-g” “genieacs”
npm ERR! node v7.10.1
npm ERR! npm v4.2.0
npm ERR! errno 1

npm ERR! libxmljs@0.18.8 install: node-pre-gyp install --fallback-to-build --loglevel http
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the libxmljs@0.18.8 install script ‘node-pre-gyp install --fallback-to-build --loglevel http’.
npm ERR! Make sure you have the latest version of node.js and npm installed.
npm ERR! If you do, this is most likely a problem with the libxmljs package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR! node-pre-gyp install --fallback-to-build --loglevel http
npm ERR! You can get information on how to open an issue for this project with:
npm ERR! npm bugs libxmljs
npm ERR! Or if that isn’t available, you can get their info via:
npm ERR! npm owner ls libxmljs
npm ERR! There is likely additional logging output above.

please suggest.

On debian 10, I work around libxmljs issue by using node 8.x. I saw some have work around it by changing the libxmljs version since those in the genieacs npm install point at a version that don’t exist anymore but I don’t know how to proceed to change that behavior.

can you suggest how to do that??
i have tried a lot but unable to do installation

On following link, you have procedure to install several node version for both Debian and Ubuntu

# Using Ubuntu
curl -sL https://deb.nodesource.com/setup_8.x | sudo -E bash -
sudo apt-get install -y nodejs