allas is a connection pooler for PostgreSQL which only supports LISTEN / NOTIFY. The idea is to allow the application to use e.g. pgbouncer in transaction pooling mode while only receiving notifications through allas. allas only uses a single PostgreSQL connection and takes care of LISTENing and UNLISTENing appropriately on that connection to make sure all of its clients get the set of notifications they're interested in.

Having installed a reasonably modern version of Go, run: go get github.com/johto/allas. This should produce a binary under $GOPATH/bin.

The configuration file is a simple JSON object. It is not documented in detail here since it will likely be replaced with something better in the near future. Here's an example configuration file:

{
    "listen": {
        "port": 6433,
        "host": "localhost"
    },
    "connect": "host=localhost port=5432 sslmode=disable",
    "startup_parameters": {
        "server_version": "9.1.15"
    },
    "databases": [
        {
            "name": "allas",
            "auth": {
                "method": "md5",
				"user": "allas",
				"password": "s3cret"
            }
        }
    ]
}

"connect" is a pq connection string. It supports many of libpq's options.