Supabase Realtime Chat

Your name
Messages are stored in Supabase table public.messages and synced in realtime.
Run this SQL in Supabase (create or upgrade)
create table if not exists public.messages (
  id bigint generated by default as identity primary key,
  room_id text not null default 'general' check (char_length(room_id) between 1 and 32),
  username text not null check (char_length(username) between 1 and 24),
  content text not null check (char_length(content) between 1 and 500),
  created_at timestamptz not null default now()
);

alter table public.messages add column if not exists room_id text;
alter table public.messages add column if not exists username text;
alter table public.messages add column if not exists content text;
alter table public.messages add column if not exists created_at timestamptz;

update public.messages set room_id = 'general' where room_id is null;
update public.messages set username = 'guest' where username is null or username = '';
update public.messages set content = '[legacy message]' where content is null or content = '';
update public.messages set created_at = now() where created_at is null;

alter table public.messages alter column room_id set default 'general';
alter table public.messages alter column room_id set not null;
alter table public.messages alter column username set default 'guest';
alter table public.messages alter column username set not null;
alter table public.messages alter column content set default '[empty]';
alter table public.messages alter column content set not null;
alter table public.messages alter column created_at set default now();
alter table public.messages alter column created_at set not null;

do $$
begin
  if exists (
    select 1
    from information_schema.columns
    where table_schema = 'public'
      and table_name = 'messages'
      and column_name = 'user_id'
  ) then
    alter table public.messages alter column user_id drop not null;
  end if;
end $$;

do $$
begin
  if not exists (
    select 1
    from pg_constraint
    where conname = 'messages_username_length'
  ) then
    alter table public.messages
    add constraint messages_username_length
    check (char_length(username) between 1 and 24);
  end if;

  if not exists (
    select 1
    from pg_constraint
    where conname = 'messages_content_length'
  ) then
    alter table public.messages
    add constraint messages_content_length
    check (char_length(content) between 1 and 500);
  end if;

  if not exists (
    select 1
    from pg_constraint
    where conname = 'messages_room_id_length'
  ) then
    alter table public.messages
    add constraint messages_room_id_length
    check (char_length(room_id) between 1 and 32);
  end if;
end $$;

create index if not exists messages_room_id_created_at_idx
on public.messages (room_id, created_at);

alter table public.messages enable row level security;

drop policy if exists "public read messages" on public.messages;
create policy "public read messages"
on public.messages
for select
using (true);

drop policy if exists "public insert messages" on public.messages;
create policy "public insert messages"
on public.messages
for insert
to anon
with check (true);

insert into storage.buckets (id, name, public)
values ('chat-images', 'chat-images', true)
on conflict (id)
do update set
  name = excluded.name,
  public = true;

drop policy if exists "public read chat-images" on storage.objects;
create policy "public read chat-images"
on storage.objects
for select
to public
using (bucket_id = 'chat-images');

drop policy if exists "public upload chat-images" on storage.objects;
create policy "public upload chat-images"
on storage.objects
for insert
to public
with check (bucket_id = 'chat-images');

create table if not exists public.message_reactions (
  id bigint generated by default as identity primary key,
  message_id bigint not null,
  username text not null check (char_length(username) between 1 and 24),
  emoji text not null check (char_length(emoji) = 1),
  created_at timestamptz not null default now(),
  unique(message_id, username, emoji)
);

alter table public.message_reactions enable row level security;

drop policy if exists "public read reactions" on public.message_reactions;
create policy "public read reactions"
on public.message_reactions
for select
using (true);

drop policy if exists "public insert reactions" on public.message_reactions;
create policy "public insert reactions"
on public.message_reactions
for insert
to anon
with check (true);

drop policy if exists "public delete reactions" on public.message_reactions;
create policy "public delete reactions"
on public.message_reactions
for delete
to anon
using (true);
No messages in this room yet. Send the first one.