herald

herald

herald means a messanger.
It is a sample app to test pub/sub of backing emqx message broker
using elio library.

If you run skaffold with k8s-resources/profiles/local.yaml,
it is configured as follows in a Kubernetes:

Installation

Download elio

$ git clone https://github.com/cppis/elio
$ cd elio

Now, $PWD is the root path.

Setting Skaffold on Windows

Skaffold settings on windows for continuous developing a Kubernetes-native app.

Run herald

using Skaffold

To use the Skaffold, you need thd following the Setup Skaffold.
To run herald using Skaffold,
run the following command in the Project root directory:

$ skaffold -f app\herald\k8s-resources\skaffold.yaml dev -p local

To change detection triggered to manual mode, use option --trigger=manual.

Or, to run herald in debugging mode using Skaffold, run the following command:

$ skaffold -f app\herald\k8s-resources\skaffold.yaml debug -p local

Test

You can test echo easily by using telnet.

app protocol is custom t2p like http.
procotol header is separated by newline(\n or \r\n).
And packet delimiter is double newline(\n\n or \r\n\r\n).

echo: echo message

echo<newline>
{message}<newline><newline>

sub: subcribe to topic

sub<newline>
{topic}<newline><newline>

unsub: unsubcribe from topic

unsub<newline>
{topic}<newline><newline>

pub: publish message to topic

pub<newline>
{topic}<newline>
{message}<newline><newline>

Reference

• Building K8S cluster of EMQ X starting from scratch

TO-DO

• Run emqx as stateful cluster in kubernetes