I have developed a Node.JS library that implements many of the USPS Publication 28 guidelines in the form of an address building class. It accepts multiple fields of address inputs, and then builds a USPS compatible address.

I plan to add many more features, including a parsing function to decompose address strings back into their components.

Let me know what you think!

NPM page: npmjs.org/package/node-usps

GitHub source: github.com/daball/node-usps