YugabyteDB

YugabyteDB is a PostgreSQL-compatible Open-Source Distributed SQL database. It adds horizontal scalability to applications built for PostgreSQL. We can use pREST works by connecting to any YugabyteDB node.

Start a YugabyteDB cluster with one of the Quick Start methods: YugabyteDB Documentation / Quick Start

Start prestd with the PostgreSQL connection string to one YugabyteDB node ( default port is 5433 )

Node locality

In a public or private cloud, there are multiple ways to scale out the pREST servers with YugabyteDB nodes:

• Start prestd with PREST_PG_URL set to a cluster service (HA proxy, Kubernetes ClusterIP...) over the YugabyteDB nodes

• Start one prestd for each YugabyteDB node, with its local IP

• change the github.com/jackc/pgx driver to the cluster-aware one github.com/yugabyte/pgx/v4, as in https://docs.yugabyte.com/preview/drivers-orms/go/yb-pgx/, so that it discovers all nodes of the cluster from any node.

With geo-distribution, it is recommended to co-locate the prestd server in the same zone as the database node(s) it connects to. This will lower the latency and increase availability.

Testing

Start a YugabyteDB cluster with one of the Quick Start methods: YugabyteDB Documentation / Quick Start

Start prestd with the PostgreSQL connection string to one YugabyteDB node ( default port is 5433 )

Example

Starting a single-node YugabyteDB cluster on Docker:

docker network create yb-net

docker run -d --hostname yb-tserver-n1 -p 7000:7000 \
  --network yb-net yugabytedb/yugabyte:2.14.6.0-b30 \
  yugabyted start --daemon false --listen yb-tserver-n1

Starting prestd connecting to this node:

docker run -d -p 3001:3000 --network yb-net \
  -e PREST_PG_URL=postgres://yugabyte:yugabyte@yb-tserver-n1:5433/yugabyte \
  -e PREST_DEBUG=true \
  prest/prest:v1

Creating a view (yb_servers() is a table function showing all YugabyteDB nodes in the cluster)

docker run --rm --network yb-net yugabytedb/yugabyte \
  ysqlsh -h yb-tserver-n1 -c "
   create view yb_servers as select host,zone,region,cloud from yb_servers()
"

Querying this view through the REST API:

curl -i -X GET "http://127.0.0.1:3001/yugabyte/public/yb_servers" -H "Content-Type: application/json"

[{"host": "yb-tserver-n1", "zone": "rack1", "cloud": "cloud1", "region": "datacenter1"}]

Starting two more YugabyteDB nodes (yb-tserver-n2 and yb-tserver-n3) to join the previous one (yb-tserver-n1):

docker run -d --hostname yb-tserver-n2 \
  --network yb-net yugabytedb/yugabyte:2.14.6.0-b30 \
  yugabyted start --join yb-tserver-n1 --daemon false --listen yb-tserver-n2
  
docker run -d --hostname yb-tserver-n3 \
  --network yb-net yugabytedb/yugabyte:2.14.6.0-b30 \
  yugabyted start --join yb-tserver-n1 --daemon false --listen yb-tserver-n3

Starting one prestd for each YugabyteDB node:

docker run -d -p 3002:3000 --network yb-net \
  -e PREST_PG_URL=postgres://yugabyte:yugabyte@yb-tserver-n2:5433/yugabyte \
  -e PREST_DEBUG=true \
  prest/prest:v1
  
docker run -d -p 3003:3000 --network yb-net \
  -e PREST_PG_URL=postgres://yugabyte:yugabyte@yb-tserver-n3:5433/yugabyte \
  -e PREST_DEBUG=true \
  prest/prest:v1

Querying any endpoint to read from the view

curl -i -X GET "http://127.0.0.1:3001/yugabyte/public/yb_servers" -H "Content-Type: application/json"

[{"host": "yb-tserver-n3", "zone": "rack1", "cloud": "cloud1", "region": "datacenter1"}, {"host": "yb-tserver-n2", "zone": "rack1", "cloud": "cloud1", "region": "datacenter1"}, {"host": "yb-tserver-n1", "zone": "rack1", "cloud": "cloud1", "region": "datacenter1"}]

curl -i -X GET "http://127.0.0.1:3003/yugabyte/public/yb_servers" -H "Content-Type: application/json"

[{"host": "yb-tserver-n3", "zone": "rack1", "cloud": "cloud1", "region": "datacenter1"}, {"host": "yb-tserver-n2", "zone": "rack1", "cloud": "cloud1", "region": "datacenter1"}, {"host": "yb-tserver-n1", "zone": "rack1", "cloud": "cloud1", "region": "datacenter1"}]

All works as with PostgreSQL, with the additional High Availability and Elasticity provided by YugabyteDB 🚀