Install the latest versions of Node.js and npm into a Docker Ubuntu container, with or without need for root access. Easily update both applications to the latest versions. Creates a new user account ('testuser') and installs common npm packages.

v1-ubuntu-docker-node-apt-get.sh

###############################################################################
# Version 1: using ‘apt-get install’
# Installs using apt-get
# Requires update to npm afterwards
# Harder to get latest copy of node
# Requires sudo to use npm
###############################################################################

# create new docker ubuntu container
sudo docker run -i -t ubuntu /bin/bash # drops you into container as root

# update and install all required packages (no sudo required as root)
# https://gist.github.com/isaacs/579814#file-only-git-all-the-way-sh
apt-get update -yq && apt-get upgrade -yq && \
apt-get install -yq curl git nano

# install from nodesource using apt-get
# https://www.digitalocean.com/community/tutorials/how-to-install-node-js-on-an-ubuntu-14-04-server
curl -sL https://deb.nodesource.com/setup | sudo bash - && \
apt-get install -yq nodejs build-essential

# fix npm - not the latest version installed by apt-get
npm install -g npm

# add user with sudo privileges within Docker container 
# without adduser input questions
# http://askubuntu.com/questions/94060/run-adduser-non-interactively/94067#94067
USER="testuser" && \
adduser --disabled-password --gecos "" $USER && \
sudo usermod -a -G sudo $USER && \
echo "$USER:abc123" | chpasswd && \
su - $USER # switch to testuser

# install common full-stack JavaScript packages globally
# http://blog.nodejs.org/2011/03/23/npm-1-0-global-vs-local-installation
sudo npm install -g yo grunt-cli bower express

# optional, check locations and packages are correct
which node; node -v; which npm; npm -v; \
npm ls -g --depth=0

v2-ubuntu-docker-node-make-sh.sh

###############################################################################
# Version 2: using curl, make, and npmjs.org’s install script
# Installs using make and shell script
# Easier to update node and npm versions in future
# Requires sudo to use npm
###############################################################################

# create new docker ubuntu container
sudo docker run -i -t ubuntu /bin/bash # drops you into container as root

# update and install all required packages (no sudo required as root)
# https://gist.github.com/isaacs/579814#file-only-git-all-the-way-sh
apt-get update -yq && apt-get upgrade -yq && \
apt-get install -yq g++ libssl-dev apache2-utils curl git python make nano

# install latest Node.js and npm
# https://gist.github.com/isaacs/579814#file-node-and-npm-in-30-seconds-sh
mkdir ~/node-latest-install && cd $_ && \
curl http://nodejs.org/dist/node-latest.tar.gz | tar xz --strip-components=1 && \
make install && \ # takes a few minutes to build...
curl https://www.npmjs.org/install.sh | sh

# add user with sudo privileges within Docker container 
# without adduser input questions
# http://askubuntu.com/questions/94060/run-adduser-non-interactively/94067#94067
USER="testuser" && \
adduser --disabled-password --gecos "" $USER && \
sudo usermod -a -G sudo $USER && \
echo "$USER:abc123" | chpasswd && \
su - $USER # switch to testuser

# install common full-stack JavaScript packages globally
# http://blog.nodejs.org/2011/03/23/npm-1-0-global-vs-local-installation
sudo npm install -g yo grunt-cli bower express

# optional, check locations and packages are correct
which node; node -v; which npm; npm -v; \
npm ls -g --depth=0

v3-ubuntu-docker-node-sudoer.sh

###############################################################################
# Version 3: version 2 without requiring ‘sudo’ to use npm
# Does NOT require sudo to use npm
###############################################################################

# create new docker ubuntu container
sudo docker run -i -t ubuntu /bin/bash # drops you into container as root

# update and install all required packages (no sudo required as root)
# https://gist.github.com/isaacs/579814#file-only-git-all-the-way-sh
apt-get update -yq && apt-get upgrade -yq && \
apt-get install -yq g++ libssl-dev apache2-utils curl git python make nano

# add user with sudo privileges within Docker container 
# without adduser input questions
# http://askubuntu.com/questions/94060/run-adduser-non-interactively/94067#94067
USER="testuser" && \
adduser --disabled-password --gecos "" $USER && \
sudo usermod -a -G sudo $USER && \
echo "$USER:abc123" | chpasswd && \
su - $USER # switch to testuser

# setting up npm for global installation without sudo
# http://stackoverflow.com/a/19379795/580268
MODULES="local" && \
echo prefix = ~/$MODULES >> ~/.npmrc && \
echo "export PATH=\$HOME/$MODULES/bin:\$PATH" >> ~/.bashrc && \
. ~/.bashrc && \
mkdir ~/$MODULES

# install Node.js and npm
# https://gist.github.com/isaacs/579814#file-node-and-npm-in-30-seconds-sh
mkdir ~/node-latest-install && cd $_ && \
curl http://nodejs.org/dist/node-latest.tar.gz | tar xz --strip-components=1 && \
./configure --prefix=~/$MODULES && \
make install && \ # takes a few minutes to build...
curl https://www.npmjs.org/install.sh | sh

# install common fullstack JavaScript packages globally
npm install -g yo grunt-cli bower express

# optional, check locations and packages are correct
which node; node -v; which npm; npm -v; \
npm ls -g --depth=0

In the first example it is the
apt-get install npm is missing after apt-get install -yq curl git nano
or simply replace it with:
apt-get install -yq curl git nano npm