Upload Base64/Blob files to Google Cloud Storage

storage.ts

import { join } from 'path'
import { get } from 'lodash'
import { Storage } from '@google-cloud/storage'
import { BUCKET_NAME } from '../constants'
import { base64MimeType } from '../utils'

const gcloudPathKey = join(__dirname, '../gcloud-key.json')

const storage = new Storage({
  projectId: 'my-project-id',
  keyFilename: gcloudPathKey
})

export const uploadAndGetPublicFile = async (
  fileName: string,
  data: Blob | string,
  defaultMimeType?: string
) => {

  const [bucketExist] = await storage
  .bucket(BUCKET_NAME)
  .exists();
  if (!bucketExist) {
    await storage.createBucket(BUCKET_NAME);
  }

  const file = storage
  .bucket(BUCKET_NAME)
  .file(fileName);

  const fileOptions = {
    public: true,
    resumable: false,
    metadata: { contentType: base64MimeType(data) || defaultMimeType },
    validation: false
  }
  if (typeof data === 'string') {
    const base64EncodedString = data.replace(/^data:\w+\/\w+;base64,/, '')
    const fileBuffer = Buffer.from(base64EncodedString, 'base64')
    await file.save(fileBuffer, fileOptions);
  } else {
    await file.save(get(data, 'buffer', data), fileOptions);
  }
  const publicUrl = `https://storage.googleapis.com/${BUCKET_NAME}/${fileName}`

  const [metadata] = await file.getMetadata()
  return {
    ...metadata,
    publicUrl
  }
}

export default storage

utils.ts

export function base64MimeType(encoded: any): string {
  var result = null;

  if (typeof encoded !== 'string') {
    return result;
  }

  var mime = encoded.match(/data:([a-zA-Z0-9]+\/[a-zA-Z0-9-.+]+).*,.*/);

  if (mime && mime.length) {
    result = mime[1];
  }

  return result;
}