SupabaseService using Singleton pattern

index.js

import SupabaseService from 'Supabase.service.js'

const supabaseUrl = 'Your app URL here'
const supabaseKey = 'Your app Key here'

// Instantiate
const supabase_instance = new SupabaseService(supabaseUrl, supabaseKey)
console.log('instance: ', supabase_instance) // Return the unique instance for the class


// Reinstantiate attempt
setTimeout(() => {
  
  const supabase_reinstance_attempt = new SupabaseService()
  console.log('reinstance attempt: ', supabase_reinstance_attempt) // Return the same instance (the first one)
  
}, 1000)


// ---- --- ---- //
// --- Usage --- //
// ---- --- ---- //

(async () => {
  const { data, error } = await supabase_instance.supabase
    .from('table')
    .select()
})()

Supabase.service.js

import { createClient } from '@supabase/supabase-js'

let instance = null

export default class SupabaseService {
  constructor(supabaseUrl = process.env.SUPABASE_URL, supabaseKey = process.env.SUPABASE_SECRET_KEY) {

    if (!supabaseUrl) throw new Error(`${SupabaseService.getClassName()} => supabaseUrl is required.`)
    if (!supabaseKey) throw new Error(`${SupabaseService.getClassName()} => supabaseKey is required.`)
    
    if (!instance) {
      instance = this
    }
    
    this.supabase = createClient(supabaseUrl, supabaseKey)

    return instance
  }

  static getClassName() {
    return SupabaseService.name
  }
}