# Use MomentJS with VuePress

# Author: Brian King | Date: Monday 11th May 2020, 2 years ago.

A static site is made up of HTML files, CSS files, and JavaScript (JS) files. A static site generator uses raw data (like markdown files) and templates to generate HTML, CSS, and JS files.

# What is VuePress?

VuePress is a static site generator that is optimized for creating technical documents using markdown files. It renders a single page app that is powered by Vue, Vue Router, and Webpack. You can even use Vue within your markdown files!

# What is MomentJS?

The MomentJS library is a free ($0), and free (open source), JavaScript wrapper for the Date object (similar in concept to jQuery being a wrapper for the JavaScript language). This library is used to validate, parse, and manipulate dates on the client-side.

# Why this post exists

I am new to VuePress. My previous static site generator was Jekyll (as a result of pushing technical documents to GitHub Pages). I switched to VuePress as a direct result of using Vue in my current projects. It's natural to document my Vue adventures with VuePress, yes?

Now I'm thinking: "Gee, that date format looks like crap!! How do I fix it?" My favourite search engine let me down completely ("No shortcuts today, you'll have to figure it out. Beep.") Oh well, here I go...

# Format VuePress dates with MomentJS

The first step is to add the MomentJS package to my current VuePress installation.

From a terminal, run the following command in the root directory of the VuePress project to download and install the MomentJS component:

$ npm install moment --save

NOTE: The --save flag adds an entry to the package.json file.

MomentJS is now ready to use in a VuePress component.

Create a component called /docs/.vuepress/components/Date.vue and add the following:

<template>
  <span>{{ formatDate($frontmatter.date) }}</span>
</template>

<script>
import moment from 'moment'

export default {
  methods: {
    formatDate(date, format = 'dddd Do MMMM YYYY') {
      moment.locale('en-NZ')
      return (
        moment(date).format(format) +
        ', ' +
        moment(date)
          .startOf()
          .fromNow() +
        '.'
      )
    }
  }
}
</script>

Create a /docs/test.md markdown file to test the component:

---
date: 2020-01-15
---

Date: <Date />

NOTE: I set the locale to 'en-NZ' in Date.vue, so the date element in the front matter above follows the YYYY-MM-DD convention.

From a terminal, run the following command to start the server:

$ vuepress dev docs

Finally, open a browser and visit http://localhost:8080/test.html🡕.

I can now drop a <Date /> component on any page that uses a date element in it's front matter.

NOTE: The BlogIndex.vue component uses a slightly modified version of the Date.vue code listed above.

# Summary

VuePress (specifically) and Vue (generally) are flexible, adaptable, and performant. It's characteristics like these that make using Vue-based technologies such a joy.