Quickstart

Prerequisites

First, install and start a Postgres database:

git clone https://github.com/rocicorp/hello-zero.git
cd hello-zero
npm install

npm run dev:db-up

In a separate terminal, start zero-cache:

cd hello-zero
npm run dev:zero-cache

In a final terminal, start the application:

cd hello-zero
npm run dev:ui

hello-zero is a demo app that allows querying over a small dataset of fake messages between early Zero users.

Here are some things to try:

Press the Add Messages button to add messages to the UI. Any logged-in or anonymous users are allowed to add messages.
Press the Remove Messages button to remove messages. Only logged-in users are allowed to remove messages. You can hold shift to bypass the UI warning and see that write access control is being enforced server-side – the UI flickers as the optimistic write happens instantly and is then reverted by the server. Press login to login as a random user, then the remove button will work.
Open two different browsers and see how fast sync propagates changes.
Add a filter using the From and Contains controls. Notice that filters are fully dynamic and synced.
Edit a message by pressing the pencil icon. You can only edit messages from the user you’re logged in as. Similar to the remove button, you can attempt to bypass by holding shift.
Check out the SQL schema for this database in seed.sql.
Login to the database with psql postgresql://user:password@127.0.0.1:5430/postgres (or any other pg viewer) and delete or alter a row. Observe that it deletes from UI automatically.