Of Course There Is A Software Project Called Zappa

Sure. As told on the Zappa webpage:

Zappa makes it super easy to build and deploy server-less, event-driven Python applications (including, but not limited to, WSGI web apps) on AWS Lambda + API Gateway. Think of it as “serverless” web hosting for your Python apps. That means infinite scaling, zero downtime, zero maintenance – and at a fraction of the cost of your current deployments!

That’s less revolutionary than Frank Zappa, of course. But it might come in handy, once I find the time to do some real Python development… Then again, you will probably beat me to it!

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Tinkering With The eeePC

We’re six years later, and I still haven’t gotten around to any kind of “Tinkering With The Raspberry Pi“. That does not mean that I still have to write down the production numbers from our solar panels by hand, however. The Asus eeePC, running Xubuntu and a bit of software a former colleague of mine and I hacked together, takes care of that. In doing so, it constructs a number of text files: one for each day, listing the current production in Wh every ten minutes, and one for each year, detailing the total production for each day. The backup of these files is made every day by a tool called ‘grive2‘ (but I’ll write about that later).

The setup works fine, almost all the time. But somehow the SMA Sunny Boy gets confused and creates ‘yearly’ files for years other than the current calendar year. Those files are utterly useless and clutter the hard disk as well as the backup, so I decided to get rid of them automatically. To prepare for the first days of a new year, the script should also be able to leave the file for the previous year in place – there may be two valid ‘yearly’ files in January, should I fail to archive the old year on New Year’s eve or on Jan. 1st.

To exercise my *nix shell skills, I decided to do that in ‘bash‘ rather than extend the current Python tools.

As is my habit, I decided to start with a demo script that does what I want on dummy data. For demo purposes the JDoodle website is a great resource, at least for ‘bash’ scripting (I did not try any of the 67 other languages available on the site). This allowed me to work on the code on my Mac-with-big-screen, and take the necessary screenshots for this post.

Here is the code I came up with:

Click on the image to get it in the form of a PDF file,
ready for copy/paste operations.

Nothing spectacular, as shown by the output. Now all I have to do is turn this into a little non-demo script and add it my crontab on the eeePC… Come and see in six years or so ;-)

PS. I’m just dabbling in bash scripting, so if there are better solutions for my problem, don’t hesitate to explain them to me, please.

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FOSS – What’s Free, What’s Open?

The SD Times website writes up the state of affairs on Free and/or Open Source Software: Open source at 20: The ubiquity of shared code. Even after 20 (or more) years, the situation isn’t always clear, certainly not for new developers. So this article is a good start if you’re new to software development.

In the year 2000 I compiled on the Free Software page in this site. I’m pleased to see that the texts and sites on the page are still relevant. Only two sites disappeared (linuxppc.org and opensourceit.com); the rest is still thriving and relevant! Well, except for the link to Reddit – still a remarkable site, but no longer just for FOSS fans.

A landmark paper about Free and Open Source Software

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Ethical Behaviour For Programmers And Other Humans

The BoingBoing website pointed me to the Programmer’s Oath. Good initiative, and I do agree with every one of the items.

As usual, of course, my mind started analysing the text, and soon concluded that 8 of the 10 tenets are not specific to programming, but could be applied to any profession! And tenets 2 and 6 don’t need big changes to make them more generally applicable. So what user Widdershin came up with is the base for moral behaviour that all humans could/should fulfill.

Well, being cynical at times just like anyone, I should perhaps exclude politicians…

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ntlmHTTP (Update 5) – This Project No Longer Necessary

I noticed some interest in my earlier posts about ntlmHTTP, and that surprised me a bit. I wrote about the subject in 2011, and that is a long time ago, in IT terms!

So to clarify things: the ntlmHTTP project is no longer required: Adobe added NTML (aka. “Windows Integrated Authentication”) support to the CFHTTP tag in ColdFusion version 11. I did rework my code from 2011, and indeed: CFHTTP did suffice to call the Microsoft Exchange web services successfully with the credentials of a special technical account.

Although I did not test it I’m pretty sure NTLM is still there in later CF versions ;-)

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AndiCar, Or The Power Of Open-Source

Considering the number of mobile apps dedicated to the subject I know I’m not alone in wanting to know the fuel consumption of my vehicles. Like my father, I have been doing that as long as I have driven motor vehicles on two and four wheels. Since 2013 or so I am using AndiCar (on Android): it has the features I want, and it’s a piece of FOSS (Free and Open Source Software). Keeping an eye on your fuel consumption is always a good idea, since a rise in numbers can be the first indicator of a problem with your vehicle.

When we bought a bi-fuel car, however, things got complicated. In November 2017, as far as I could tell, there were no apps that had full support for “hybrid” or bi-fuel vehicles. I had no choice but to start experimenting a bit, and I settled on testing an app called Fuelio as a possible alternative for AndiCar. I won’t do a complete comparative review of these two: let me just explain that AndiCar is faster for data entry (at least in my situation: I enter the data in the evening or in the weekend, when I’m at home, not in the gas station), and Fuelio is the better looking app.

Some of the statistics available in the apps I mentioned (AndiCar on the left, Fuelio on the right). The numbers do not correspond because the periods are different, not because of errors ;-)

So I mailed Miklós, the author of AndiCar, explaining my situation. I probably wasn’t the first one to mention the “multi-fuel problem” to him. Nevertheless I’m quite impressed with the fact that six weeks later he already published a new version of AndiCar that allows detailed data entry for hybrid vehicles like mine. To top it off, he also mailed me to tell me about the new version!

One of the advantages of AndiCar is that it allows you to define your own fuel types. I actually use three types of fuel, since we have two types of CNG in Belgium: low caloric content (L) and high caloric content (H) gas. AndiCar is perfectly capable of handling that.

As a happy person I simply had to respond to Miklós – here’s the core of my mail:

Good work, man! You impressed me with the speed with which you implemented the support for alternative fuel vehicles. I’m not just giving you last version “a look”: I have copied all the fill-ups of my new car into AndiCar, of course.

For the moment I will continue to compare AndiCar with Fuelio, if only to get a feeling for what might constitute a good solution for the “fuel consumption/efficiency calculation” issue, as you call it. The Fuelio solution is not good enough: it just uses the distance between the two latest fillings for that type of fuel. But that results in silly numbers when driving most kilometers with one type of fuel, interspersed with an occasional fill-up of the alternative fuel (and that’ what I try to do: run mostly on CNG because it’s cleaner, just switching to petrol when no CNG is available).

What is probably needed, is a system whereby it is possible to indicate for each fill-up whether it can be used for a consumption calculation based on the previous fill-up of the same fuel type. Or perhaps an extra odometer field ? Or …? I realise that my situation is different from that of people with electric hybrid cars: my g-tron runs on CNG as long as there is enough of it in the tank, and switches to petrol with an explicit warning the moment that switch happens. In e-hybrids the rules are completely different, and I have no ideas about how AndiCar (or any other app) could support such calculations – I suppose those cars can do it themselves ;-)

Oh well. I’m already quite happy with the work you’ve done, so thanks again!

PS. I ran into one issue when entering my fill-ups in AndiCar: trying to “convert” an existing entry to the new fuel type and UOM crashed the app (I tried it several times). But of course, deleting the existing entry and reentering the data in a new entry solved the issue, so no real harm done.

If only all software makers would be so friendly and so quick to react to their users!

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Unexpected Timestamp Effects In ColdFusion’s Query Of Queries

At work I’m busy moving all the ColdFusion applications from Windows 2003 servers with CF8 to new virtualised servers with Windows 2012 running CF11. Configuring Windows and IIS are also much more complicated than ten or more years ago, but we have that under control now. Most of the ColdFusion (and Java) code transfers without a problem, and I spend more of my time deleting scripts and components that are no longer used than modifying code.

Until this week, when I stumbled over a script that shows an inventory of the active Scheduled Tasks on the server, together with the link to their respective output (which we write to a network drive)… To do that, the code gets the data from the file, and then we put all the data in a handcrafted Query object. The names of the tasks and the links displayed fine, but there was something wrong with the start and end times: “1899-12-30” is not a time!

It took me hours to figure out what was wrong, because I was focusing on the date and time formatting functions used to format the data before adding them the query. Why the formatting, you ask? Well, we wanted to sort the data on columns containing start and end times, and in previous versions of CF our solution was to prepare the strings before adding them to the Query – seemed like a good way to make sure that ‘11:00:00 AM‘ and ‘11:00:00 PM‘ turned up in the right place of a sorted column.

So what was wrong with our code? Let me quote the “Query of Queries user guide”:

If you create a query object with the QueryNew function and populate a column with date constants, ColdFusion stores the dates as a string inside the query object until a Query of Queries is applied to the query object. When ColdFusion applies a Query of Queries to the query object, it converts the string representations into date objects.

Our code added strings formatted as “hh:mm” to the Query object, but once we filtered or sorted that Query using QoQ those columns were transformed into datetime objects. ColdFusion 11 then adds that time to the default date used, i.e. “1899-12-30“.

Clearly, that was not the case in earlier versions of ColdFusion – at least not in CF8. There are multiple solutions to solve this problem, once you know what’s going on – so now our overview displays everything as intended.

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Dear Developer: When Reporting Exceptions, Please Be Clear

I’m currently trying to automate the creation of datasources in ColdFusion server instances, in order to facilitate a number of migrations our machines and applications have to go through. For the record: this turns out to be reasonably simple, once you get the knack of using the ColdFusion Administrator API classes (if I find the time, I’ll write about that later).

One thing slowed me down: a typical error message without much meaning. This is what I received when recreating (or at least trying to recreate) an Oracle RAC datasource:

java.sql.sqlrecoverableexception: IO Error: NL Exception was generated

I wonder why developers often invent error messages that do not tell us what really went wrong. In this case, it turned out that I forgot to copy a single closing parenthesis at the end of the JDBC connection string. Let’s call that a syntax error, Oracle, and please give a significant message if I mess up! Or is it Adobe’s ColdFusion that is hiding more explicit and clear details about what went wrong?

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Great Job, Even If It’s Utterly Useless: b2fj

I appreciate the fun one can have at building programs and tools that do something thought to be impossible. Running Java code on a Commodore C64 is such a project.

Back to the Future Java (b2fJ) aims at bringing the power of Java to 8-bit home computers of the ’80s. This project provides a toolchain to cross-compile Java programs under Windows.

You’ll find everything about “b2fJ – Back to Future Java” on Github.

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Kotlin: A Strangely Named Programming Language Brings Smiles To Coder’s Faces

The language isn’t new: Kotlin was created more than 5 years ago by JetBrains engineers. A preview version was released in 2011. Kotlin is a statically typed programming language for the Java Virtual Machine (JVM). Being crude, you could say that it’s “just another” enhancement of the Java language, just like Groovy or Scala. Nice, but hardly indispensable.

But Kotlin made a name for itself in May 2017, when Google announced “that it is making Kotlin […] a first-class language for writing Android apps” (in the words of Frederic Lardinois on TechCrunch). The Wired website has a bit more info on why the language was developed and why it is so “hot” these days. And the article concludes:

And its applications extend well beyond Google’s platform. Like Java, it can be used to write apps that run on desktops and servers as well. Plus, JetBrains has released tools for translating Kotlin code into code that can run on iOS or even in web browsers. All of which is to say, you can expect to find yourself using apps written in Kotlin more and more often in the coming months and years.

I have not yet written a line of Kotlin, but perhaps I should try that sooner rather than later. Since I’m also looking at Apple’s Swift language, the combination of learning both could be beneficial… or problematic, since someone asserts that both are quite similar (but not the same, of course): see “Swift is like Kotlin” for details.

I still would like to know how the name “Kotlin” was chosen…

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Visual Studio For Mac Is Officially Available To All

Of course I’m going to try this out: “Huzzah, Visual Studio for Mac is now available to all“!

Click the image to see more details about the product

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Staying Power For Old Beemers

Last weekend, I spotted two old BMW motorcycles on the road in the port of Antwerp (Belgium). I had my camera in my hands, so I managed a few badly-framed photos – you can see them on Flickr.

By chance, I also spotted an advertisement for a similar bike. I don’t pretend to be a specialist on the subject, but I haven’t seen many BMW R50/2’s in this color scheme (not even on Google Images), and I find this combination quite flattering!

A fine-looking oldie, as seen in one
of the last advertisements on Kapaza

When I said I found this “zoekertje” by chance, I meant that I just had a quick look at the Kapaza website, because the site announced just last week that it will be closing down in a few days. I have visited that site, with its thousands of advertisements for second-hand stuff in many categories, while on the prowl for say another bike or a special lens for my camera. Kapaza is (was) one of the few big Belgian websites that used ColdFusion for at least parts of its site, and that made me pay a bit more attention to it also. This is one more website that won’t last half a century and more, unlike the motorcycle shown here!

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Don’t Use Directory Name ‘/api’ For Your Own Uses In ColdFusion 11

Last week, I did loose a lot of time in what should have been a quick ColdFusion hack. My colleagues and I were just trying to set up a web service-based solution for a simple problem: they had a JavaScript page that needed a bit of data for which I already had the code in ColdFusion. So I created a new directory in an existing application, whipped up the required code in ‘index.cfm‘ to return a bit of JSON and tested the result from my browser… only to get an “Error 500 - Application index.cfm could not be found“.

Weird, heh? The required file was there, so why could CF11 not find it? Adding an ‘Application.cfm‘ did not help, neither did repackaging the code in a CFC. On CF8, on the other hand, everything worked as expected. So what was going on?

It took some time, but I did find the explanation: CF11 reserves the directory name ‘api’ for special treatment, so you can’t use it like any other directory name – and of course that was the name I had chosen! Adam Tuttle described the situation nicely in 2015:

Funny you should mention that the issue is inside an /api folder. I’m trying to track down the same problem, except I’m directly accessing an index.cfm (sort of — onRequest intercepts the request and redirects to CFCs as appropriate — it’s a Taffy API) and I’ve found that renaming the folder from /api to … literally anything else… works fine. It’s almost as if something in CF has special meaning at /api, like the special /rest mapping does.

Indeed, renaming my directory solved the problem – too bad it took me so long to find the cause. On to the next problem!

PS. Adam Tuttle has more to say on the subject, but his post on the subject has disappeared: the URL ‘http://fusiongrokker.com/post/coldfusion-11-sometimes-chokes-on-api‘ no longer points to the relevant text, but is redirected to another blog also belonging to Adam Tuttle. There, unfortunately, the post is NOT available. I won’t call this a case of linkrot, but it’s not good either. Luckily, the Wayback Machine has a copy of the page, including a few comments…

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The Resurrection Of The Userland Frontier Application Server

Brent Simmons isn’t a new name in this blog – I have cited his name several times since 2001. A few days ago he wrote:

It’s been years since I could build the Frontier kernel — but I finally got it building.

[…]
The high-level goal is to make that tool available again, because I think we need it.

The plan is to turn it into a modern Mac app, a 64-bit Cocoa app, and then add new features that make sense these days. (There are so many!) But that first step is a big one.

“Frontier Is Interesting”, says Jim Roepcke – click to see what he writes

It’s an interesting development, from several viewpoints. I wrote some of my first “web applications” in Frontier, and that makes that Frontier will always have a special place in my book of tools. It’s also nice to see a relevant piece of software evolve so that it continues to run on modern hardware and OS’s. At some point, I will certainly download and run a copy on my Mac.

But the question is: do I want to go back to developing stuff in Frontier? Do you want to?

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How To Install An Old Pyusb Package On Xubuntu

It’s something I need to remember: how do I install an old PyUSB package on Xubuntu (or a similar Debian-based OS). Why, you ask? Because I need that old version 0.4.3 for the little script that reads the solar energy numbers from the SMA Sunny Beam.

The SMA Sunny Beam monitor for our solar panel installation

Luckily, it isn’t too hard to do. This is my context:

• I am using Python 2.7
• I’m not certain the 0.4.3 version is compatible with newer versions of Python
• You need a copy of the relevant archive file called ‘pyusb_0.4.3.orig.tar.gz‘ (which you can find here: http://ftp.ubuntu.com/ubuntu/ubuntu/pool/universe/p/pyusb/)

Step one is to make sure you have the required header files to compile the PyUSB package. So you open up a terminal session and execute

sudo apt-get install libusb-dev
sudo apt-get install python-dev

Step two: Extract the root folder and all the files from the PyUSB archive, and make that folder your current directory in the terminal session.

Step three: compile and install the package with this command:

sudo python setup.py install

That’s it. When all goes well, you’ll be able to verify the existence of two new files on your system, in a directory called “/usr/local/lib/python2.7/dist-packages“:

usb.so
pyusb-0.4.3.egg-info

Done!

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