While working on a project with Moo (the first time for me) I discovered Try::Tiny. It's a great little helper and I highly recommend it. However, on my quest to make better error handling in Perl I thought it would be a good idea to have some kind of exception system.

Turns out, this already exists. In fact it is quite simple: die() accepts a reference as parameter, which could very well be an object. A couple of modules on CPAN make use of this, one of the simplest with the fewest dependencies is Throwable.

Since I could not find a good example of how to use it correctly (which I understood), I'm going to post such an example here for anyone who might be interested.

So, you need to have Moo and Throwable installed first. I'm doing these kind of experiments with perbrew, which I recommend as well! Here's my "Exception" class. It's a Moo role with two attributes (type and msg) and a class method e().

package Ex;
use Moo;
with 'Throwable';
has type => (is=>‘ro’);
has msg  => (is=>‘ro’);
sub e {
if (ref($) eq ‘Ex’) {
return $;
} else {
chomp; return Ex->new(msg => $_, type=>0);
}
}

This Exception class will act as our wrapper to throw exceptions or convert old school perl die()'s into exceptions.

Here is a simple Moo class without any attributes which implements two methods X::Nix::tu() and X::Nix::ta(). Both of them just die. The method tu() throws an exception of type Ex - our exception class from above comes into use here. The ta() method on the other hand just dies with a good old croak() call.

package X::Nix;
use Carp;
use Ex;

use Moo;
sub tu {
Ex->throw({type => 1, msg => ‘dont die while root’});
}
sub ta {
croak “death by disruptor”;
}

Now let's take a look at our main script, which uses the X::Nix class and tries to catch both exceptions:

package main;
use Try::Tiny;
use X::Nix;
my $x = X::Nix->new();
try {
$x->tu;
} catch {
printf “died with %d and said: <%s>\n”,
Ex::e->type, Ex::e->msg;
};
try {
$x->ta;
} catch {
printf “died with %d and said: <%s>\n”,
Ex::e->type, Ex::e->msg;
};

It calls both methods and tries to catch them. Note how it calls Ex::e->type, though: Try::Tiny puts the exception object/message into $_. The class method Ex::e() uses $_ directly, therefore we are able to leave it in our catch{} code. This is the same thing as Ex::e($_)->type. Here's the output:

died with 1 and said: <dont die while root>
died with 0 and said: <death by disruptor at role.pl line 49.>

So, as you can see, with the help of our Ex::e() class method we can handle real exceptions and old school die()'s the same way, wo don't need to distinguish between the two. This way you can use foreign perl modules which use croak() and die() and catch those errors as if they were exceptions.

Hab ich noch nie gesehen, Streifen quer über den ganzen Himmel:

2016-09-27 - Streifen Panorama 2:

2016-09-27 - Streifen Panorama 1:

Last month I got an email from OTTO.de asking me to attend a survey about customer satisfaction and the like. Bad for them: I use mutt and therefore it is obvious if an email is fake. So, what did OTTO.de do? They gave my email address (and I suspect those of all other customers) to an external "reasearch" company. This company then sent the email using the mail service of another company. All of this happened without my consent.

Now, the good news is, that OTTO.de responded quickly to my complaint and ordered both companies to delete my email address, however I cannot be sure if they actually DID delete it though. The other good news is that I create always an email address for every shop, forum or any other login site I use. That way, I can just drop "burned" email addresses and stop using the single service for which I created it.

But most peope do not operate their own mail server and create an alias for every site they use. For such peope a "burned" email address is a disaster. By "burned" I mean the email address is out of your control, you don't know who's using it anymore, you start to receive SPAM to this address. But if this is the only email address you possess and if you use it for everything, you're fucked. Changing an all-purpose email address, deposited on dozens or even hundreds of sites, is a nightmare.

I have this problem at work. One of our vendors, an israeli company, sends us notifications by email. At work I only have one email
address, it's associated with my name and I cannot change it. The israeli company sends those notifications by using the services of a company called Sendgrid. Now, sendgrid not only knows my name, my location, my employer, they also know what kind of job I have and that our company uses the services of this israeli company.

I never allowed them to do this. And I cannot change this, it already happened. My work email address is burned and I have to continue using it. This is more than annoying.

Much more annoying is the fact, that people using such services don't even think about it. I complained with the israeli company and they did not understand my problem at all. It was as if I am from mars trying to communicate with people from venus. They even nonchalantly closed the case.

What I tried to say to them was that Sendgrid is a SPAM sending service. And it is a US company, operating in a country with almost no privacy protection laws. They didn't get it. I suspect, young people don't even understand what SPAM is these days, I don't know.

The other day I stumbled upon the story about the operatos of vDOS, a DDoS service. It was a criminal enterprise and they used a mail sending service as well: Mailgun. Mailgun does the same as Sendgrid. It's a SPAM sender company. In order to understand the
nature of their business, look at the numbers:

Sending 5.000.000 emails costs 0.00015 Dollars.

How do they make profit, you ask? Well, look at this, which can be found in a job description:

We have a passion for solving hard problems – our services are
responsible for processing billions of messages each month and have to
not only scale, but be highly reliable.

I don't know who else needs to send such impossible amounts of emails than SPAMmers. And if all of their customers operate like OTTO.de or the mentioned israeli company, almost nobody agreed to this.

An email you receive from a sender you don't know, you don't have any relationship with, you don't do business with - is SPAM. Period.

The only difference to past times is that operating an email sending venture was an illegal operation while today it is perfectly okay for all parties, including their victims.

I've got to admit they are clearly geniuses. Converting a foul smelling "business" into something you get venture capital for, create APIs, get praised by managers AND developers is a coup I need to salute for.

But how much all those hipsters, ruby-on-rail-loosers and java-scriptsters love services like Mailgun or Sendgrid: what they do stinks, it violates peoples privacy without asking (and I didn't even talk about their tracing features!) and in the end burns peoples 
productive email addresses.

I can't even imagine how such a company can be a legal business. This is incomprehensible.

Update 2016-10-02:

And yet another one:

[..]
Received: from m69-130.mailgun.net (m69-130.mailgun.net [166.78.69.130])
From: noreply@shop.drak.de
[..]

This time, DRAK an aquaristic vendor, uses Mailgun, to send unsolicited SPAM mails to me In this case as well I didn't give my consent. In the case of DRAK, even their TOS claims that they'd not do such things (that is, give customer data to a third party without consent).

Update 2016-09-16:

Here's another example:

[..]
Received: from mailer212.agnitas.de (mailer212.agnitas.de [87.119.210.180])
From: voelkner - direkt günstiger  
[..]

Agnitas.de, yet another SPAM sending venture, sends mails in the name of Voelkner (also known as fake mails) to me. So, Voelkner gave them my email address without my consent.

What the fuck?!

Ich habe gestern diese Hamburger Brioche Buns hergestellt. Zur Abwechslung habe ich mich präzise an das Rezept gehalten, keine anderen Mehlsorten, kein LM usw. Einzige Änderung: Teig nach Bertinet bearbeitet und nicht geknetet. Und was soll ich sagen: Die Brötchen waren der Hammer und die Hamburger sensationell.

Wir haben gefressen. Alter war das geil.

Bilder:

2016-09-04 - Sowas von!:

2016-09-04 - Profi-Patties: Rindsgulasch fein, Rinderfilet und Entrecote grob, 2 Finger dick Schweineschwarte, Salz, Pfeffer, bischen Semmel mit Milch, wenig Ei: Boah ey!:

2016-09-04 - Wie vorhergesagt erfüllen die Brötchen alle Anforderungen an ein Hamburgerbrötchen. Top! Übrigens erkennt man an der nicht ganz so regelmäßigen Porung die andere Teigbearbeitungsmethode.:

2016-09-04 - Die Brötchen. Guck Dir das mal an!:

Das erste Mal im Leben hab ich Marmelade gemacht: Pflaumenmuß und Holundermarmelade.  Mit Rezepten aus dem 19ten Jahrhundert. Und die Sachen sind wirklich lecker. Nur ein bischen viel ist es geworden.

Bilder:

2016-08-28 - Holunderbeeren: 4 Stunden Arbeit für diese Schüssel:

2016-08-28 - Ein bischen Kompott ging auch noch:

2016-08-28 - 38 Gläser Pflaumenmuß, haha!:

2016-08-28 - Aber: 18 Gläser Marmelade waren es wert:

2016-08-28 - Pflaumen in rauen Mengen: