The following packages have unmet dependencies: nodejs : Conflicts: nodejs-legacy

while setting up an iquidus explorer i just hacked my way to nodejs-legacy installing freedom through sheer elan ... maybe


after being given access to someone elses pre-loved server,
was getting error whilst trying to install nodejs-legacy

The following packages have unmet dependencies:

 nodejs : Conflicts: nodejs-legacy

not entirely which bit was the real magic but after an extended duration of getting constant rejections this is hopefully the bare basics,
possibly it's more than everything necessary.
remove nodejs, install nodejs from nodesource, change package manager priority to ubuntu servers, upgrade nodejs, install nodejs-legacy


remove current nodejs

# apt-get remove nodejs

update etc

# apt install -f

# apt update

# apt dist-upgrade

install nodejs v10 from the horses mouth (ie nodesource itself)

# curl -sL https://deb.nodesource.com/setup_10.x | sudo -E bash -

# apt-get install nodejs -y

..

etc

..

# nodejs -v

v10.0.0

adjust priority to ubuntu servers and upgrade to v10.25

# apt-cache policy nodejs

nodejs:

  Installed: 10.0.0-1nodesource1

  Candidate: 10.0.0-1nodesource1

  Version table:

 *** 10.0.0-1nodesource1 0

        500 https://deb.nodesource.com/node_10.x/ trusty/main amd64 Packages

        100 /var/lib/dpkg/status

     0.10.25~dfsg2-2ubuntu1 0

        500 http://archive.ubuntu.com/ubuntu/ trusty/universe amd64 Packages

# nano /etc/apt/preferences.d/nodejs

.. in my case i gave archive.ubuntu.com a higher value by adding the following

Package: *

Pin: origin archive.ubuntu.com

Pin-Priority: 1002

..

# apt-cache policy nodejs

nodejs:

  Installed: 10.0.0-1nodesource1

  Candidate: 0.10.25~dfsg2-2ubuntu1

  Version table:

 *** 10.0.0-1nodesource1 0

        500 https://deb.nodesource.com/node_10.x/ trusty/main amd64 Packages

        100 /var/lib/dpkg/status

     0.10.25~dfsg2-2ubuntu1 0

       1002 http://archive.ubuntu.com/ubuntu/ trusty/universe amd64 Packages

re-install and success !!

# apt-get install --reinstall nodejs 

.. updates nodejs ..

# apt-get install nodejs-legacy

discussion on raising the package priority
https://github.com/nodejs/help/issues/1040#issuecomment-362970187