Hub Dependencies

Docker is not a required dependency, but we highly recommend it. Docker is a great way to bundle services in simple and composable packages. For the examples below, we will assume that you have Docker installed. You can find installation instructions for Docker here.

The Cardstack Hub uses a PostgreSQL database to persist the content index. Additionally, the PostgreSQL DB is used to orchestrate job queues used for indexing.

A PostgreSQL DB can also serve as a data source for content. But for this example, we’ll just be using Ethereum as our data source.

The Cardstack Hub will automatically try to attach to the default PostgreSQL DB, postgres://postgres@localhost:5432/postgres; however, you can specify a PostgreSQL DB using the standard PostgreSQL environment variables (PGHOST, PGPORT, PGUSER, etc), or you can specify a PostgreSQL URL to your database using the environment variable DB_URL.

For our example, let’s just use the default PostgreSQL DB. We have provided a handy Docker container that you can use to easily spin up a PostgreSQL database:

docker run -d -p 5432:5432 --rm cardstack/pg-test

This will start a PostgreSQL database on port 5432 on your local system.

The Cardstack Hub server is written in Node.js.