Docker: Install node 12 with nvm (Node Version Manager)

Dockerfile.spinnet

# updating NODE
# to install node 12 we need install with nvm because the new 
# installation method (see https://deb.nodesource.com) is only 
# supported from version 18

ENV NVM_VERSION v0.39.6
ENV NVM_DIR /usr/local/nvm
ENV NODE_VERSION v12.22.12

RUN mkdir $NVM_DIR

RUN apt-get install -y curl  \
    && curl -o- https://raw.githubusercontent.com/creationix/nvm/$NVM_VERSION/install.sh | bash

ENV NODE_PATH $NVM_DIR/$NODE_VERSION/lib/node_modules
ENV PATH $NVM_DIR/versions/node/$NODE_VERSION/bin:$PATH

RUN echo "source $NVM_DIR/nvm.sh && \
    nvm install $NODE_VERSION && \
    nvm alias default $NODE_VERSION && \
    nvm use default" | bash