John Aaron Nelson

Configure package.json variables with npmrc

March 11, 2016

With NPM and package.json we can unify our script (task) running, which works great for building and deploying code. But we can’t stick our username and password in the package.json if we want to keep our password private. So how do we include a deploy script with package.json, keep our information private, but still check in changes to Git? We use npm config variables…

One of the most overlooked yet important aspects of npm is the config file. Using npm config to set our npm username and password is required to deploy any packages to npm. But we don’t want to include all of our project specific credentials in one global config file. It would quickly pollute the global config file. Coming to the rescue are package-specific .npmrc files.

Create a .npmrc file that resides next to the package.json file. Inside package.json use $npm_package_config_<variable> to refer to the config:{varible: ''} section of package.json. But sticking our credentials in there kind of defeats the purpose of using variables, since they’re declared in the same file!

We can override the local config with a project config in the .npmrc file. Create variables with the syntax <package>:<variable>=<value> with the package matching the name in your package.json

If we wanted to skip the local and project config files, we can go straight to the global config with $npm_config_<variable>.

Further reading… The Ultimate Guide to Configuring NPM
npm config

John Nelson

Written by John Nelson, who lives and works in Chattanooga, building things for Clearbit.