issue with fetch while using adapter-cloudflare-workers

Describe the bug I am using supabase-js with sveltekit and cloudflare-workers. While using adapter-cloudflare-workers, I get hit with following issue when I do wrangler dev.

Uncaught
ReferenceError: require is not defined
    at node_modules/node-fetch/lib/index.js (worker.js:59:18)
    at __require (worker.js:9:44)
    at node_modules/cross-fetch/dist/node-ponyfill.js (worker.js:1099:21)
    at __require (worker.js:9:44)
    at node_modules/@supabase/gotrue-js/dist/main/lib/fetch.js (worker.js:1152:41)
    at __require (worker.js:9:44)
    at node_modules/@supabase/gotrue-js/dist/main/GoTrueApi.js (worker.js:1442:19)
    at __require (worker.js:9:44)
    at node_modules/@supabase/gotrue-js/dist/main/index.js (worker.js:2149:39)
    at __require (worker.js:9:44)

This issue happens because supabase-js is using cross-fetch as its fetch-polyfill. I found a workaround by applying following patches

• changing platform from node to browser in the esbuild options inside adapter-cloudflare-worker.
• patching cross-fetch to export native fetch for browser polyfill.

node may have been chosen as a platform of choice for esbuild, since cloudflare has started supporting node libraries for its workers platform.

However, cloudflare provides a hybrid of browser(service-worker) and node environment with native fetch support. Hence, if I keep node as a platform, then I face issues with browser’s native object such as fetch, websocket that are also available under cloudflare’s service-worker environment.

I have couple of questions here

• Would it make sense to change the platform from node to browser. This will essentially conform to intrinsic nature of service-worker environment supporting many of the browser’s native objects.
• Is there a way to customise esbuild options used for a given adapter?
• As per esbuild team, to override any external dependency, one way is to write a custom plugin such as esbuild-plugin-external-global. Is there a way to pass custom plugin or 3rd party plugin to esbuild config used during adapter build?

Logs

I have provided the error logs in my issue above

To Reproduce Here’s a sample repo.

supabase url + apikey and cloudflare account_id + zone_id will be required to reproduce issue

Expected behavior

cloudflare-worker adapter should allow options to customise esbuild so that third party libraries using cross-fetch can be integrated to cloudflare environment.

Stacktraces If you have a stack trace to include, we recommend putting inside a <details> block for the sake of the thread’s readability:

Stack trace

Uncaught
ReferenceError: require is not defined
    at node_modules/node-fetch/lib/index.js (worker.js:59:18)
    at __require (worker.js:9:44)
    at node_modules/cross-fetch/dist/node-ponyfill.js (worker.js:1099:21)
    at __require (worker.js:9:44)
    at node_modules/@supabase/gotrue-js/dist/main/lib/fetch.js (worker.js:1152:41)
    at __require (worker.js:9:44)
    at node_modules/@supabase/gotrue-js/dist/main/GoTrueApi.js (worker.js:1442:19)
    at __require (worker.js:9:44)
    at node_modules/@supabase/gotrue-js/dist/main/index.js (worker.js:2149:39)
    at __require (worker.js:9:44)

Information about your SvelteKit Installation:

Diagnostics

System:
    OS: macOS 11.4
    CPU: (4) x64 Intel(R) Core(TM) i5-6267U CPU @ 2.90GHz
    Memory: 21.73 MB / 16.00 GB
    Shell: 3.2.1 - /usr/local/bin/fish
  Binaries:
    Node: 16.3.0 - ~/.local/share/nvm/v16.3.0/bin/node
    npm: 7.15.1 - ~/.local/share/nvm/v16.3.0/bin/npm
  Browsers:
    Chrome: 91.0.4472.101
    Chrome Canary: 93.0.4539.0
    Edge: 91.0.864.41
    Firefox: 86.0.1
    Safari: 14.1.1
  npmPackages:
    @sveltejs/kit: next => 1.0.0-next.114
    svelte: ^3.34.0 => 3.38.2

Severity This is hampering me from running supabase together with sveltekit on cloudflare. I believe that this issues goes beyond supabase. If not supabase, many other libraries use cross-fetch to access their apis. Hence, they may potentially face this issue.

Additional context

[Rich-Harris]

Closing since there’s a viable workaround. Hopefully libraries will stop bundling things like cross-fetch, now that more and more runtimes expose it natively

[The-Noah]

This fixed it for me:

{
  fetch: (...args) => fetch(...args),
}

Source: https://github.com/supabase/postgrest-js/pull/235