TravisCI: Use custom Node.js version within container based builds

Sometime you may need a special version of Node.js or a recent version within a foreign build environment. But in the modern container-based infrastructure it is not possible to use apt to install custom packets which are not whitelisted. As an workaround, you can download pre-build binaries via wget into your build directory and add the bin/ dir to your PATH. This allows you to use any pre-build third party software without installation.

Example: PERL with javascript testcases#

os: linux

language: perl

perl:
  - "5.24"
  - "5.14"

# skip perl (cpanm) dependency management
# install nodejs into home folder
install: 
  # fetch latest nodejs archive
  - wget https://nodejs.org/dist/v8.8.1/node-v8.8.1-linux-x64.tar.gz -O /tmp/nodejs.tgz
  # unzip
  - tar -xzf /tmp/nodejs.tgz
  # add nodejs binaries to path - this has to be done here!
  - export PATH=$PWD/node-v8.8.1-linux-x64/bin:$PATH
  # show node version
  - node -v
  - npm -v
  # install node dependencies
  - npm install

script:
  # syntax check
  - perl -Mstrict -Mdiagnostics -cw rsnapshot
  # run javascript based tests
  - npm test