gatsby-config.js

require("dotenv").config({
  path: `.env.${process.env.NODE_ENV}`,
})
module.exports = {
  siteMetadata: {
    title: `Gatsby Firebase Authentication`,
  },
  plugins: [
    `gatsby-plugin-react-helmet`,
    `gatsby-plugin-postcss`,
    {
      resolve: `gatsby-plugin-create-client-paths`,
      options: { prefixes: [`/app/*`] }
    },
    {
      resolve: "gatsby-plugin-firebase",
      options: {
        credentials: {
          apiKey: process.env.GATSBY_FIREBASE_API_KEY,
          authDomain: process.env.GATSBY_FIREBASE_AUTH_DOMAIN,
          databaseURL: process.env.GATSBY_FIREBASE_DATABASE_URL,
          projectId: process.env.GATSBY_FIREBASE_PROJECT_ID,
          storageBucket: process.env.GATSBY_FIREBASE_STORAGE_BUCKET,
          messagingSenderId: process.env.GATSBY_FIREBASE_MESSAGING_SENDER_ID,
          appId: process.env.GATSBY_FIREBASE_APP_ID,
        }
      }
    }
  ]
}