How to be a C# developer

C# has never been considered as a cool language (fact: It was initially called COOL – C-like Object Oriented Language) – it’s a good language, very good indeed, but because of it is “created by Microsoft” and then “tied to .NET platform”, it lost the coolness to other languages – JavaScript, C, Scala, you name it.

The table has turned and the wind has changed. Microsoft has been making bold moves with all the open source projects that run multi platforms. Once known as the “evil” of software industry, Microsoft is changing their image to be good again. And with Xamarin being free – C# is the language to learn now – if you have not already. Being a very good OOP language with powerful functional programming features, and built on a mature platform and excellent tools and library, you can use C# for almost everything these days – mobile, desktop, server, and even client.

So how?

Visual Studio Community:

Visual Studio is simply one of the best IDEs out there, and while missing some of the features, Visual Studio Community is free – so it’s perfect choice if you are a student or simply learning the language. It can be downloaded from here:

https://www.visualstudio.com/en-us/products/visual-studio-community-vs.aspx

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Big and beautiful: A quick Phillips BDM3270QP review

My screen finally arrived and I’ve spent a couple of days playing with it. It is the screen I wanted, and I tried to search about it quite a lot, but the English content about it is quite limited, so I decide to write one here, in case you’re looking for some reviews before buying it.

Why BDM3270QP?

In the specs, this screen is completely a steal. 32 inches, QHD (2560×1440) resolution, AMVA 10 bit panel (so 1.07 billion of colors), stand which supports titling, pivoting etc,… And it’s only 4390 SEK here (equivalent to 534 USD, but hey, I am in Sweden, where everything is crazy expensive, remember?), which is even cheaper than many other 27″ QHD screens. I have a habit (not sure good or bad) of checking everything before buying, and this is the list I come up with:

Plus:

+ Big size. 32″ 2560×1440 is just right, considering the distance between my eyes and the screen. 27″ QHD is a bit small, while 32″ 4k is a bit too much pixels (which makes thing smaller than I’d like). And 4k non-TN panel screens are much more expensive currently.
+ AMVA. It’s not TN! It might not be as good as IPS in term of color reproduction and viewing angles, but it’s 10 bit panel (of course that requires extra parts like the connection, the machine to make it works) so it should be comparable on some level. And VA, in general, is better than IPS in terms of contrast (black level) and not-glowing.
+ Rich in port and connection. I have anything I’d like to and more: DisplayPort, HDMI, DVI, USB (2×3.0 and 2×2.0).

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Articles software developers should read, at least once

… if not twice.

These days, almost every software developer has a blog – so it’s sh*tloads of content around the Internet. Truth is, the good, accurate, long-lasting contents are hard to be found. Most contents are supposed to be obsolete very soon – and it’s OK, because many contents are for a very specific situation in a very specific time. But can we have a collection of the precious contents that are useful not only today, this week, this month, but ten years from now?

This is supposed to be a definitive collection of great contents that will be helpful for your entire career as a software developer. It’ll be updated frequently, with new link as I found it.

The Log: What every software engineer should know about real-time data’s unifying abstraction (Jay Kreps)

Logging is essential to every serious software system. But it’s not easy – getting it right can be indeed hard, especially in real-time. This article provides a deep knowledge about the concept.

http://engineering.linkedin.com/distributed-systems/log-what-every-software-engineer-should-know-about-real-time-datas-unifying

The Absolute Minimum Every Software Developer Absolutely, Positively Must Know About Unicode and Character Sets (Joel Spolsky)

It’s been 26 years since Unicode was introduced and still, not all people can get it right. This article gives you – as the tittle suggests – a minimum knowledge about Unicode, and how to not get it wrong.

http://www.joelonsoftware.com/articles/Unicode.html

What Every Programmer Should Know About Memory (PDF) (Ulrich Drepper)

This is a pretty low-level paper, you will learn about how memory works at hardware level. Still interesting and useful. Who knows someday you’ll have to get your hands dirty with some memory stuffs?

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Hiring process might suck, and how to fix it

I recently read this post F*** You, I Quit — Hiring Is Broken
found it interesting. If you have time – read it (and of course you should have, because this blog is far less famous than medium – the combination of page views for post in this blog is very likely to be much smaller than that single post).

I feel bad for the author for being in such situation – getting rejected 5 times in a row, is a hard thing to swallow. Especially when he is considered famous in developer’s world/ and has big passion in coding. And it’s not the first time, we hear someone rants about the hiring process, and it’s very unlikely to be the last. Let’s agree that the hiring process for developers might suck.

But then, it’s the way it works.

The first time no offer given, it’s probably their fault. The second time no offer given, it’s probably a bad luck. The third time no offer given, it’s probably your fault.

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The quirks of coupons

If you have been using the promotion system in Episerver Commerce (or should I call it “old promotion system” – the “new promotion system” is almost out of BETA and it will soon be the promotion system), you should know about the coupon – which is an option setting for a promotion. When it is set, the customers will be required to input that special code in order to get the reward, even if their carts fulfilled all other requirements (the subtotal, the lineitems, the shipping method etc.)

The coupon in old promotion system is quite basic – you can set only one per promotion, or nothing at all. Advanced scenarios like customer-specific coupons (there are multiple coupons and each of them is valid for only one customer) are not supported. (This is one of reasons why you should consider to move to new promotion system ASAP). You can use redemption limits in combination to specify how many times a coupon can be used. But in this post we will talk about the quirks of storing it.

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Upgrade your website to Commerce 9

You know what – Commerce 9 is released. OK, I’m just kidding, it was released 6 months ago, in October 2015. Last week, Commerce 9.12 was released, and at this time of writing, Commerce 9.13 is on the oven just released. So it’s not so new – but with 6 months on the field, I think Commerce 9 has proven it’s stable and production-ready to be your next version. If you are looking for an upgrade to your website, Commerce 9 is the obvious choice. Many customers have successfully upgraded their sites to Commerce 9 – and the results have been very encouraging.

But it does not mean that upgrading is easy. Commerce 9 is undoubtedly a big upgrade, and getting there is not just an easy walk. So how to ensure a successful upgrade?

Plan ahead:

The catalog subsystem was rewritten almost entirely in Commerce 9, resulting in some very big migration steps. Depends on the size of your catalog, it can take from a couple of minutes, to hours (I would not be too surprised if it takes a day). So plan for the possible down time (even though in most cases you will be upgrading your site in staging first).

Commerce 9 is also a major release, so there were breaking changes – you will have to fix some of your code, to make it compiled. The amount of code that actually broken should be small, but it’s better if you check this list http://world.episerver.com/documentation/Items/Upgrading/EPiserver-Commerce/9/breaking-changes/ to see how much works you’ll need (tips: the less you use “internal stuffs”, the code you’ll have to change. The internal stuffs are, by convention, marked with special doc tag.).

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Understand the retry policies in Episerver

This is pretty internal stuffs – you will almost never use it yourself (you technically can, but there is no guarantee of backward compatibility whatsoever). I learned the stuff recently and found it interesting enough to share.

No matter how powerful your server(s) are, and how reliable SQL Server is, there are chances that a query can result in error. Hell, there are bunches of error codes that can be returned (and I never remember one, Google made a pretty bad habit of forgetting everything). But they can be divided into two categories:

  • The un-retry-able errors, such as a grammar error in your stored procedure, or a parameter is missing, or mismatch. These errors need human-interaction to correct them before continuing.
  • The retry-able errors, which means if you re-run the query, there is a chance that it would eventually succeed. Compared to the un-retry-able errors, these are in smaller number. A deadlock can be considered as retry-able (with the hope that the deadlock conditions are no longer present, the other threads finished their works and released the locks). A timeout error can be considered as retry-able (with the hope that the server can run the query faster, this time). In the end, your query can succeed, after some tries.

You might ask, why retry? The question is, why not? Retrying the query can make it works, and as it’s transparent from end-users perspective, it might provide a smoother experience for them. Say, they are trying to place an order. Because of your highly successful campaign, there are a lot of customers trying to do the same thing at the same time, resulting in some occasionally deadlocks. You’ll be much happy to silently retry and have another order in place, than showing “Something went wrong” to the customers. Of course, the previous errors will still be logged for further analytic, but you’re good for now.

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Make Microsoft Edge works with local sites

At Episerver, we haven’t officially supported Microsoft Edge, yet. Our QA:s do not test on it. And of course no one of us uses it for development. It has a big drawback of not supporting local sites:

Edge with local site

http://Commercedev/ is a local development site on IIS, which we add to hosts file like this:

127.0.0.1  commercedev

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Episerver Commerce SearchProvider – demystifying

This post is an excerpt from my book, but it’s the short one. It looks like there is a confusion of where the searchprovider is used in Commerce

Many important features in Commerce Manager use index-based search provider to search for entries – it’s simply faster and more flexible to work with. They might not be truly “real-time”, but they’re close (with the right configuration). The only drawbacks are they require extra processing (for indexing entries), external files/configurations, but the advantages easily overweight any of those drawbacks.

There are three search providers provided by Episerver Commerce: LuceneSearchProvider, Solr35SearchProvider, and FindSearchProvider (four if you count SolrSearchProvider as well). LuceneSearchProvider comes as the default option with EPiServer.Commerce.Core, and it’s the only one does not require extra configurations.

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UX design lessons – from a metro perspective

When I come to a new city, I usually pay close attentions to its metro system. Of course, it rarely shows up in TripAdvisor as an attraction of the city, but for me, it’s not only a necessity (based on a quite tight budget, public transportation is almost always our first choice), but also can tell a lot more about the history of the city, the people and the daily life here.

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New York metro system . Make sure you don’t look at the rails.

I’m not a traveler myself, I have visited only Rome, Paris,  Venice, Florence London, San Francisco and New York, and of course Stockholm – where I am living. Venice and Florence have no metro I’d know of, and I only tried BART (Bay area rapid transport) in San Francisco, so only metro systems in remaining cities count. In those five, I know Stockholm metro system (tunelbanna) the best, and like it the most, so this post can be highly biased opinion. If I did misunderstand a metro system, kindly point it own.

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