MQTT, OpenHAB2, sonoff and home automation

I found out about sonoff about a year ago but never purchased any for quite some time, and then when I did purchase them, they’ve been sitting in the drawer gathering dust. Due to the recent flurry of activity about them on youtube and the internet at large, I’ve been prompted to take a closer look at them and they are VERY impressive!

SmartHouse—Jonathan Oxer

Jon has a few videos dedicated to the sonoff devices, and these are very good if you don’t know what they are. And even if you do know what they are, there’s still some good information in his videos. He is a wealth of knowledge on more than just the sonoff devices with general electrical engineering as it relates to home automation.

I would recommend having a look at this video and then paying a visit to his website:

SuperHouse Episodes

Matt Kaczynski—MK-SmartHouse

I haven’t seen many of the videos on this channel as of yet, but Matt is using a lot of the technology and ideas that I have. For example, he uses OpenHAB2, sonoff devices and is integrating these with the likes of Siri and Alexa to create a custom home automation experience.

This video is an introduction to his setup. It wasn’t until the later half of the video that I realised he uses OpenHAB, something that I have already begun to introduce to my home.

After watching the video I visited his website and found the connections I have been looking for, namely MQTT, and OpenHAB. He has recently revamped his website and it has several guides and general information on his methodologies regarding home automation.

https://www.mksmarthouse.com/guides

Stop by and visit his channel here:

https://www.youtube.com/channel/UC1WPn_mBd7eDmz7lMSXR5bA/videos

Bruh Automation

https://www.youtube.com/channel/UCLecVrux63S6aYiErxdiy4w

I have been following a few of the Bruh youtube channel videos as he’s incorporated modern technology into his home automation. However, he uses an opposing technology to what I have setup. It’s like comparing Holdens and Fords, or Republicans or Democrats. It’s largely personal preference, setup and features. I use OpenHAB where Bruh uses Home Assistant.

There’s nothing wrong with home assistant, it’s just that I’d spent a bit of time setting OpenHAB up and it works on older devices (such as the original iPad running iOS 5.1.1) which Home Assistant does not.

Still, his channel includes some good videos on the subject and I do recommend a visit to his channel.

Lawlessness on the roads

how to navigate an intersection

I have long come to realise that Australia is a nanny state of rules and regulations. There’s a rule for just about everything, and I’m starting to realise this is beginning to hamper us when in reality these sort of things should be making our lives better. Safer.

After having spent a lot of time in Thailand and using Thai roads and the lawlessness that apparently goes with driving in Thailand, you can come to both appreciate the rules we have on one hand, but despise them at the same time.

There are times where (especially in the middle of the night) where you can seemingly spend an eternity at a set of traffic lights for no apparent reason. I have a set of traffic lights at the end of my street, and I have to admit, they are pretty speedy on letting traffic out of our street. You only have to stop there for a moment and the lights begin to change. This appears to be the case even if it has only just turned red. The wait is never very long.

Yet there are traffic lights where they seemingly take forever. What’s with that?

Why are there stop signs for turning left on roads where you can see the approaching traffic for half a kilometre?

Why are there red arrows against turning right when there’s no approaching traffic at all? This one can be especially infuriating.

Paris Traffic

I remember seeing a photograph of a classic Parisian roundabout when I was at school, and I remember thinking “How do they do it? It’s chaos! How does anyone not get killed?”

As a kid I couldn’t see it. As a young adult I couldn’t see it either. Our lives are built around a network of safety measures and molly coddling. Rules and regulations designed to give us a “right of way” and a feeling of security as well as entitlement.

It’s this entitlement that breeds complacency on the roads. A righteousness that forgoes common sense. Road rage built around “he just cut me off,” or “I have the right of way!”

But what if we took that entitlement away? What would happen then?

People speed through intersections because they feel “safe” in the knowledge that other traffic should be giving way to them. But what if other traffic didn’t have to give way?

What if we took away the very things that apparently made our roads safer?

One of my favourite presenters, “99% invisible” teams up with Vox and illustrate just how it’s done elsewhere and removes some of the “molly coddling.”

DST

Daylight Saving Time

According to this server

Fri, 27th Apr 2018, 01:13:37 AEST Australia/Sydney (1524755617)
This timezone is currently in standard time.
Standard time began on: Sun, 1st Apr 2018, 02:00:00 AEST
Daylight saving time begins on: Sun, 7th Oct 2018, 01:00:00 AEST
In Sun days, on Sunday morning at 03:00:00 (3:00 AM), the clocks need to be put back -60 minutes.

I have always thought there would have to be a programatic way of determining when daylight saving started and finished. I know that it’s an arbitrary date and it’s subject to change, but I knew there would be a way to somehow look it up.

I’ve been looking for this before and never really came across anything and even when looking at the date/time functions in php, and even though gettimezone retrieves the current timezone (including whether or not DST is currently in force or not), it didn’t do much to solve the “when does it start next” problem.

Then one day I was playing in the backend of a website and I noticed there was two lines of text under the timezone information that was intriguing:

DST Info

I opened up the trust text editor and went fishing inside the server.

Now, I’m pretty sure I’ve seen timezone_transitions_get before, but for whatever reason, something never clicked. It’s EXACTLY what I was looking for!

In the DateTimeClass there are a myriad of functions to do with what the offset from UTC is, what effect DST has on the timezone, is it in effect now, amongst others; including get_transitions. This returns all the DST transitions for the time zone, past and future.

The only caveat ere is your version of php would have to be reasonably up-to-date in the event that a local government changes when DST will start and finisg. and although that probably wouldn’t be too often, it’s something that still must be considered.

This snippet I’ve created here isn’t perfect, it’s just bits and pieces cobbled together and it does need a good cleaning out. However, I’ve included it here and it’s available to you if you’d like to use it under the MIT license.

add_shortcode('DST_Info', 'mad_dst_info');

function mad_dst_info(){
$r = "
<style>
table {
  border-collapse: collapse;
}
td {
  text-align:center;
  padding:10px;
  border: 2px solid black;
}
</style> \n"  ;


$day    = 1;
$month  = 1;
$year   = 2018;

$time = mktime(12,0,0,$month,$day,$year);

$time = gettimeofday(time(),true);
  
function _t1($arg) {
 return "  <tr><td colspan='2'> $arg </td></tr>\n";
}
function _t2($arg1, $arg2) {
 return "  <tr><td> $arg1 </td><td> $arg2 </td></tr>\n";
}

$my_format="D, jS M Y, H:i:s T ";

$current_offset = timezone_offset_get();
$tzstring = ini_get('date.timezone');
$tzstring = "Australia/Sydney";
date_default_timezone_set($tzstring);

$r .= "<table>";
	$r .= _t1("<h2>According to this server</h2>");
	$r .= _t2( date($my_format, time()) , "$tzstring (".time().")");

	$check_zone_info = true;

    // Set TZ so localtime works.
    date_default_timezone_set($tzstring);
    $now = localtime(time(),true); ////////////////////////////////////////////////////////////////////////time(), true);
    if ( $now['tm_isdst'] ){
		$r .= _t1("This timezone is currently in daylight saving time.");
    } else {
		$r .= _t1("This timezone is currently in standard time.");
    }
    $allowed_zones = timezone_identifiers_list();

    if ( in_array( $tzstring, $allowed_zones) ) {
      $found = false;
      $date_time_zone_selected = new DateTimeZone($tzstring);
      $tz_offset = timezone_offset_get($date_time_zone_selected, date_create());
      $right_now = time(); ///////////////////////////////////////////////////////////////////////////////////time();
      foreach ( timezone_transitions_get($date_time_zone_selected) as $tr) {
        if ( $tr['ts'] > $right_now ) {
            $found = true;

          break;
        }
        $tr_old = $tr;
      }

      if ( $found && $tr['offset'] != "UTC") {

        $message = $tr_old['isdst'] ? 'Daylight saving time began on: ' : 'Standard time began on: ';
          $r .= _t2( "  $message ",date($my_format , $tr_old['ts'] + ( $tz_offset - $tr_old['offset'] )));

        $message = $tr['isdst'] ? 'Daylight saving time begins on: ' : 'Standard time begins on: ';
          $r .= _t2( "  $message ",date($my_format , $tr['ts'] + ( $tz_offset - $tr['offset'] )));
		
		$damxdaystogo = date("D" , $tr['ts']);
		$damdayofweek = date("l" , $tr['ts']);
		$damtimeofday = date("H:i:s (g:i A)" , $tr['ts']);
		$damadjustment = ($tz_offset - $tr['offset'])/60 ;
		$dambackforward = ($damadjustment < 0) ? "back" : "forward";
		$message = "In $damxdaystogo days, on $damdayofweek morning at $damtimeofday, the clocks need to be put <em>$dambackforward</em> $damadjustment minutes.";
		  $r .= _t1( "  $message ");
		
		
      } else {
        $r .= _t1( 'This timezone does not observe daylight saving time.' );
      }
    }

    // Set back to UTC.
    date_default_timezone_set('UTC');
    date_default_timezone_set($tzstring);
	$r .=    "</table>";
  return $r;
}