Jenkins slave with nodejs to run npm publish - node.js

Question

I have a dockerfile where I install nodejs. I create a container from that dockerfile to use as a slave in jenkins. The problem is that when I try to publish (npm publish --registry ...) it says that I need to login first. But I cannot use npm adduser in a jenkins file cause you have to enter user and password manually when it is required. I have tried to add the file .nmrw with a valid token, but it haven't worked. Any idea?
Best regards.
FROM jenkins/ssh-slave
# Install selected extensions and other stuff
RUN apt-get update && apt-get -y --no-install-recommends install && apt-get clean
RUN apt-get install -y curl
# Install nodejs
RUN curl -sL https://deb.nodesource.com/setup_8.x | bash -
RUN apt-get install -y nodejs && apt-get install -y nginx

Answer 1

The key is in the file .npmrc. You have to have the same server you publish to.
FROM jenkins/ssh-slave
# Install selected extensions and other stuff
RUN apt-get update && apt-get -y --no-install-recommends install && apt-get clean
RUN apt-get install -y curl
ARG NODEJS_VERSION=setup_11.x
# Install nodejs
RUN curl -sL https://deb.nodesource.com/${NODEJS_VERSION} | bash - && apt-get install -y nodejs && apt-get install -y nginx
RUN chown -R jenkins:jenkins /home/jenkins && chmod -R 777 /home/jenkins
COPY .npmrc /home/jenkins/.npmrc
RUN npm -v