Migrate Google Cloud Storage (GCS) to Supabase Storage

migrate-gcs-supabase.js

/**
 * 1.) Make sure you have the `GOOGLE_APPLICATION_CREDENTIALS` environment variable
 *     set to the path of your local service account credentials.
 *     @see https://cloud.google.com/storage/docs/reference/libraries#setting_up_authentication
 *
 * 2.) Make sure you have the `SUPABASE_URL` and `SUPABASE_KEY` environment variables set
 *     with the proper values from your Supabase Project API page.
 *
 * Install dependancies: `npm install --save node-fetch form-data @google-cloud/storage`
 */

const fetch = require("node-fetch");
const FormData = require("form-data");
const { Storage } = require("@google-cloud/storage");

const SUPABASE_API_URL = process.env.SUPABASE_URL;
const SUPABASE_AUTH_TOKEN = process.env.SUPABASE_KEY;
const SUPABASE_BUCKET_ID = "YOUR_SUPABASE_BUCKET_ID";

const GCS_BUCKET_ID = "YOUR_GCS_BUCKET_ID";
const GCS_BUCKET_PREFIX = "SUB_FOLDER_TO_MIGRATE/";

const gcs = new Storage();
const gcsBucket = gcs.bucket(GCS_BUCKET_ID);

console.debug("Starting...");

gcsBucket.getFiles({ prefix: GCS_BUCKET_PREFIX }).then(async (data) => {
  const files = data[0];

  for (const file of files) {
    try {
      await upload(file);
    } catch (err) {
      console.error(err);
    }
  }

  console.debug("Done!");
});

/**
 * Stream an upload to Supabase.
 *
 * @returns {Promise}
 */
function upload(file) {
  const path = file.name;
  const { contentType, size } = file.metadata;

  const form = new FormData();
  form.append("file", file.createReadStream(), {
    contentType,
    filepath: path,
    knownLength: size,
  });

  return fetch(
    `${SUPABASE_API_URL}/storage/v1/object/${SUPABASE_BUCKET_ID}/${path}`,
    {
      method: "POST",
      body: form,
      headers: {
        Authorization: `Bearer ${SUPABASE_AUTH_TOKEN}`
      },
    }
  ).then(() => {
    console.debug(`Processed file: ${path}`);
  });
}

This is awesome @danalloway!
One feedback - you actually don't need the apiKey here. Just the Authorization header is enough.

updated

Nice! We need to support this natively within supabase-js. Been thinking of how to support it without bloating the library too much. As in this example, form-data is required in Node.js but not required if you are using supabase-js purely on the client side.

Nice! We need to support this natively within supabase-js. Been thinking of how to support it without bloating the library too much. As in this example, form-data is required in Node.js but not required if you are using supabase-js purely on the client side.

What if the Supabase Storage API supported accepting a file stream as the POST body?

https://github.com/node-fetch/node-fetch#post-data-using-a-file-stream

this would remove the need for form-data and you could just rely on node-fetch which is already present because I think I saw you were using cross-fetch

Great!... Is it possible to move everything from GCS bucket to Supabase bucket(with extact subfolder path) without mentioning GCS_BUCKET_PREFIX