Anyone used Phoenix + Supabase?

I think it’s targeted at frontend devs as a replacement for some of backend functionality, hence the firebase mention.

You can utilise the same tech-stack in your phoenix app as the supabase server, I think there were some recent commits that make it possible to subscribe for logical replication using postgrex.

• Add Postgrex.Replication by josevalim · Pull Request #575 · elixir-ecto/postgrex · GitHub
• before the PR above, GitHub - cainophile/cainophile · GitHub was used by some people, including supabase/realtime, while googling for it I even found a tutorial: https://www.stackbuilders.com/tutorials/elixir/todo-with-postgresql-cdc-phoenix/

What i’d like to do is use supabase as my database.

It seems a bit roundabout to use supabase from an Elixir application, but you can issue requests to postgrest with http and listen to supabase realtime notifications with a phx channel client.

Basically you’d do

elixir -http-> postgrest -sql-> postgres -wal-> supabase/realtime -phx-> elixir

instead of

elixir -sql-> postgres -wal-> elixir

They actually discussed in this podcast the other day (https://thinkingelixir.com/podcast-episodes/073-elixir-at-supabase-with-paul-copplestone/) about not having example for elixir. But as mentioned here, since you already use elixir/phoenix you get a similar offering, where as, their main market is frontend (ie. react) so competing against Firebase.

Also, thinking elixir does some great podcasts: Thinking Elixir Podcast

They could have digged a little deeper there in the podcast.
As I understand it, it may still be valuable to use supabase from Elixir because you get easy and robust multi tenancy. On the other hand it may not be be worth it because supabase has to charge you for all the great features that are only interesting for Jamstackers. Supabase is (obviously) more expensive than a postgres instance on AWS for example.

It seems to me like Supabase might be worth using from Phoenix just because it provides an authentication system Auth | Supabase Docs

So, pg replication can be used like notify/listen?

It’s better because LISTEN/NOTIFY messages have a size limit. Of course, you can chunk messages, attach an identifier to each chunk, buffer and reassemble them in your application.

What @ruslandoga said is the answer.

I’m using Cainophile to listen to the Postgres wal and bust caches, as an example. It’s awesome. Today you’d probably want to use Postgrex.Replication and then decode the messages with Cainophile.

Almost everything that Supabase is doing you can do with just Postgres. Although, as of last week realtime supports row level security. walrus is what does that. But yeah even though realtime is powered by Elixir and Phoenix the dev story for Elixir folks is not there.

They are definitely targeting front-end devs who typically don’t have the ability to easily connect directly to the database. So instead of writing your API in Node you just spin up a Supabase instance and automatically have an API generated for you based on your Postgres schema. Auth is another difficult thing for most people so providing an easy solution for people is important for adoption (it’s one of the reasons Firebase became so popular).

Yeah you wouldn’t want to use the HTTP interface they expose to access Postgres when we have direct connections.

There is I think a max of 10 replication slots for Postgres so if you have a larger cluster it might make sense to use Supabase to listen to the wal over Pubsub.

It’s fully open source too so if you do want to play with it you can spin it up yourself.

Yep!!

@chasers, it looks like logflare.app is joining forces with Supabase (according to their blog)?

I’ve actually extracted out the WAL listening stuff from Supabase Realtime (which is based on Cainophile) into a package: GitHub - agoodway/walex: Postgres change events (CDC) in Elixir [WAL] · GitHub

I’ve been using this along with Hasura (Supabase wasn’t around when I started) so that I can handle business logic right in Elixir. The main differences are that I’ve added a supervisor to process Events and I’m casting to Elixir types instead of Json.