Quick way of having docker image with integrated apple social identity provider. 

FROM maven:3.5-jdk-11 AS builder

RUN git clone https://github.com/BenjaminFavre/keycloak-apple-social-identity-provider.git
WORKDIR /keycloak-apple-social-identity-provider
RUN mvn package 

FROM jboss/keycloak:16.1.1
COPY --chown=jboss:root --from=builder /keycloak-apple-social-identity-provider/target/apple-social-identity-provider-1.0.2.jar /opt/jboss/keycloak/standalone/deployments/

MQTT is a lightweight, publish-subscribe network protocol that transports messages between devices. Golang has a very nice client which can be easily used for the purpose.

For example here is how to send data to my public free MQTT Broker - xMQTT

package main

import (
	"fmt"
	mqtt "github.com/eclipse/paho.mqtt.golang"
	"log"
)

func main(){
	var broker = "broker.xmqtt.net"
	var port = 8883

	opts := mqtt.NewClientOptions()
	opts.AddBroker(fmt.Sprintf("tcps://%s:%d", broker, port))
	opts.OnConnect = func(client mqtt.Client) {
		log.Println("Connected")
	}
	client := mqtt.NewClient(opts)
	if token := client.Connect(); token.Wait() && token.Error() != nil {
		panic(token.Error())
	}

	for i := 0; i < 100; i++ {
		t := client.Publish("/random/test",0,false,fmt.Sprintf("event_id %d",i))
		t.Wait()
	}

	client.Disconnect(5)
	log.Println("Events sent")
} 

Haproxy is an awesome load balancer for TCP and HTTP connections. In this short post we will see how to secure bind by source IP address Configuration of HaProxy to allow and reject connections by IP Address: For doing this we will use ACL to check source IP and based on it we will decide how to proceed.
In my use case I want to publish RabbitMQ management interface to few public users. It will be served through different from 80/443 port. So my config looks like:

listen port_5672
  bind :15672
  mode tcp
  acl network_allowed src 1.1.1.1 2.2.2.2.2
  tcp-request connection reject if !network_allowed
  server rmq_rmq1_1 127.0.0.1:25672 check

Note: RabbitMQ management interface is running on port 25672
So as you can see I’m adding new listener on port 15672 which backend will be 127.0.0.1:25672. Interesting part here is ACL conditions

acl network_allowed src 1.1.1.1 2.2.2.2.2
tcp-request connection reject if !network_allowed

It’s a pretty straightforward and self-explanatory. Of course this can be used in frontend section as well.
For example:

frontend www
  bind *:80
  mode tcp
  acl network_allowed src 1.1.1.1 2.2.2.2
  tcp-request connection reject if !network_allowed
  use_backend backend_server_original

Happy codding!

Developing in go typacly involve installing a lot of packages. A common scenario is from time to time to update all of them to their latest versions. This can be done easily with

go get -u all

Last few days I was working on first version of Managment interface for project of my friend "RunEasyMail". In short it is a collection of bash scripts which automates installation and configuration of email server.
My contribution for this is connected with managment part of users and for now is REST API which makes adding/removing users and domains very easy.
More information about project can be found at https://www.runeasymail.com/.
Any suggestions, requests and bug reports are wellcomed for API at https://github.com/runeasymail/ManagementAPI