tekumara / nats-demo

nats demo running in a local kubernetes cluster

nats demo

nats demo running in a local kubernetes cluster.

Getting started

Prerequisites:

• k3d (for creating a local kubernetes cluster)
• kubectl
• helm

Install nats cli, create k3d cluster and deploy nats:

make install

Usage

Endpoints:

• nats: tcp://localhost:4222
• nats monitor: http://localhost:8222

Run

• make ping
• make demo-js python jetstream demo
• nats stream ls list streams
• nats server report connections list connections
• nats server ls --context=admin list servers using system account (admin)
• nats server report jetstream --context=admin jetstream summary report
• nats kv watch articles tail bucket dwatch
• nats stream view KV_dwatch view messages in the KV_dwatch stream
• nats stream get KV_dwatch 2 view message with sid 2 in KV_dwatch stream
• nats consumer rm KV_dwatch delete consumer. Recreating it will start from the beginning of the stream.
• nats events -a listen for advisories eg: delivery attempts exceeded

Config

Stored in /etc/nats-config/nats.conf.

NB: /etc/nats/nats-server.conf is the default example config built into the docker image.

References

• How NATS stores data on disk
• NATS Server Helm chart
• NATS Protocol Demo
• NATS cli
• NATS configuration

Troubleshooting

nats: error: server request failed, ensure the account used has system privileges and appropriate permissions

Connect using the system account.

nats: error: nats: Authorization Violation

Use the username and password when connecting, eg: