siren.go

package main

// Credits: http://stackoverflow.com/a/24683083/351947
import (
    "encoding/binary"
    "encoding/json"
    "fmt"
    "io/ioutil"
    "net/http"
    "unicode/utf16"
    "unicode/utf8"
)

const alertsUrl = "http://www.oref.org.il/WarningMessages/alerts.json"

type Record struct {
    Id    string   `json:id`
    Title string   `json:title`
    Data  []string `json:data`
}

// LazyUTF16BytesToString converts UTF-16 encoded bytes, in big or little endian byte order,
// to a UTF-8 encoded string.
func LazyUTF16BytesToString(b []byte) string {
    if len(b)%2 != 0 {
        panic("len(b) % 2 != 0")
    }

    var codec binary.ByteOrder = binary.LittleEndian
    if b[0] == 0xFE && b[1] == 0xFF { //check and strip the BOM
        b = b[2:]
        codec = binary.BigEndian
    } else if b[0] == 0xFF && b[1] == 0xFE {
        b = b[2:]
    }

    utf := make([]uint16, (len(b)+(2-1))/2)
    for i := 0; i+(2-1) < len(b); i += 2 {
        utf[i/2] = codec.Uint16(b[i:])
    }
    if len(b)/2 < len(utf) {
        utf[len(utf)-1] = utf8.RuneError
    }
    return string(utf16.Decode(utf))
}

func main() {
    client := &http.Client{}
    req, err := http.NewRequest("GET", alertsUrl, nil)
    perror(err)

    req.Header.Add("Content-Type", "application/json; charset=utf-8")
    res, err := client.Do(req)
    perror(err)

    defer res.Body.Close()
    body, err := ioutil.ReadAll(res.Body)
    perror(err)

    bodyString := LazyUTF16BytesToString(body)

    var record Record
    err = json.Unmarshal([]byte(bodyString), &record)
    perror(err)
    fmt.Println(record)
}

func perror(err error) {
    if err != nil {
        panic(err)
    }
}

siren.php

#!/usr/bin/env php
<?php

// Number of seconds to set polling rate
const INTERVAL = 3;

class Siren {

	// Command to run when there's an alert
	protected $command  = '/usr/bin/notify-send ":msg"';

	private $last_title;

	public function poll()
	{
		$payload = file_get_contents('http://www.oref.org.il/WarningMessages/alerts.json');
		if (empty($payload))
			throw new Exception('Empty payload, aborting.');

		// Converting encoding to UTF-8 and removing BOM
		$payload = iconv('UCS-2', "UTF-8", $payload);
		$payload = str_replace("\xEF\xBB\xBF", '', $payload);

		$alerts = json_decode($payload, TRUE);
		if (empty($alerts))
			throw new Exception("Invalid payload. ERROR: ".json_last_error_msg());

		if ($alerts['title'] != $this->last_title)
		{
			$this->notify($alerts['title']);
			$this->last_title = $alerts['title'];
		}

		foreach ($alerts['data'] as $alert)
		{
			$this->notify($alert);
		}

	}

	private function notify($msg)
	{
		$cmd = strtr($this->command, [ ':msg' => $msg ]);
		exec($cmd);
	}

}

$siren = new Siren;
echo 'Polling alerts every '.INTERVAL.' seconds...'."\n";

while (TRUE)
{
	$siren->poll();
	sleep(INTERVAL);
}

siren.py

#!/usr/bin/env python2
#-*- coding: utf-8 -*-

import urllib2
import json
import subprocess
import time

opener = urllib2.build_opener()
req = urllib2.Request('http://www.oref.org.il/WarningMessages/alerts.json')
title = ""
while 1:
    f = opener.open(req)
    data = json.loads(f.read().decode('utf16'))

    if (title != data['title']):
        print(data['title'])
        title = data['title'];

    if (data['data']):
        print(data['data']);

    time.sleep(5);