Download data from Cloud Firestore and store locally to be used for Nuxt Content

migrate-firestore-nuxt-content.js

const fs = require('fs')
const admin = require('firebase-admin')
const TurndownService = require('turndown')
const turndownService = new TurndownService({
  codeBlockStyle: 'fenced'
})

const serviceAccount = require('./path/to/serviceAccountKey.json')

admin.initializeApp({
  credential: admin.credential.cert(serviceAccount)
})

const db = admin.firestore()

function convertToMarkdown(value) {
  return turndownService.turndown(value)
}

function escapeQuotes(value) {
  return value.replace(/"/gi, '\\"')
}

function buildFrontMatter(data) {
  const createdAt = data.created.toDate().toISOString()
  const updatedAt = data.changed.toDate().toISOString()

  let tags = '';
  if (data.tags.length === 0) {
    tags = '[]'
  } else {
    for (const tag of data.tags) {
      tags += `\n  - ${tag}`
    }
  }

return `title: "${escapeQuotes(data.title)}"
subtitle: "${escapeQuotes(data.teaser)}"
lead: "${escapeQuotes(data.lead)}"
description: "${escapeQuotes(data.description)}"
createdAt: ${createdAt}
updatedAt: ${updatedAt}
cover: 
  image: "${data.imageUrl}"
  alt: "${escapeQuotes(data.title)} cover image"
  caption: "${escapeQuotes(data.imageCaption)}"
  thumb: "${data.teaserImageUrl}"
tags: ${tags}`
}

async function main() {
  const blogsRef = db.collection('blogs')
  const snapshot = await blogsRef
    .where('published', '==', true)
    .orderBy('created')
    .get()

  for (const doc of snapshot.docs) {
    console.log(`Exporting ${doc.id}`)

    const data = {
      ... {
        lead: '',
        imageCaption: '',
        description: ''
      },
      ...doc.data()
    }

    console.log(doc.data())

    let markdown = `---
${buildFrontMatter(data)}
---
${convertToMarkdown(data.body)}`

    try {
      fs.writeFileSync(`/path/to/app/content/blog/${doc.id}.md`, markdown)
    } catch (err) {
      console.error(err)
    }
  }
}

main()