Jeremy Davis
Sitecore, C# and web development
A colleague of mine recently hit upon an odd issue with the Sitecore integration for the 51Degrees browser detection service. It worked fine for most of his testing, but raised an exception in some circumstances. Trying to dig into this and create a test to demonstrate the bug kept us amused for a few hours – maybe it will help you to?
It's easy to get distracted by all the shiny big features that get deployed in new releases of Sitecore, but every so often a little gem slips past almost without comment. Except in the release notes...
The one thing that is true of every aspect of IT is that it is always changing. And that change means that things you were confident of in the past may no longer hold true.
I was reminded of this while sitting in the pub with some developers recently, talking about querying for items by path in Sitecore. The debate about the best way to do this raged, but a common thread of the debate was that it is often said that the fastest way to find a set of items you needed is via a ContentSearch index. That assumptions has its roots in the time when most sites were using Lucene to run queries, and for queries with more complex matching rules. But does that hold true here?
Every so often you come across a small config change which does stuff you just did not expect. I hit an issue around this recently, which I figured I should document to try and prevent anyone else getting to spend time with diff, scratching their head for as long as I did...
A lot of projects I've worked on over the years have had requirements about consuming content feed data over the internet. Whether they're Sitecore projects or not, "we need to display the contents of an RSS Feed" is a fairly common requirement. It should be nice and simple. There are standards and schemas for feed formats like RSS and Atom, so the data should be predictable and easy to handle...
Unfortunately, back in the real world, this rarely seems to be the case. I still regularly come across feeds which don't match the schema, or in extreme cases feeds that aren't even well formed. Sadly some people still seem to think that string concatenation is the way to build XML...
So what are your choices for handling feed data, and how can you try and get around bad-data challenges?
When you're working with a "provider" model for services in your applications you get used to the assumption that everything follows the Liskov Substitution Principle and whatever provider you plug in will work in the same way. Unfortunately, for software our in the real world that's not always entirely true. Recently I came across an example of this which helped point out a bug in some search code in Sitecore...
The other day I realised that my home server hadn't sent me it's daily "Health Report" email. Having done the usual simple test of "is the server up?" and "what happens if I reboot it?", I ended up digging through the Event Log and Google to work out what was wrong. In case this happens to me again, or happens to you, here's what I found:
One of the big things in IT security in recent times has been the successful attacks black-hats have launched against the infrastructure of cryptography. As we all come to rely on encrypted communications more and more, the vulnerabilities in old ciphers have become more of a problem to us developers and administrators. Vulnerabilities like Drown and Poodle are just two examples of a trend which means we all now have to worry about how our crypto is configured before we allow the internet to see a server.
But whenever you tie down security more tightly you risk causing problems when software relies on the thing you've just disabled...
I spent some time recently investigating why certain aspects of the Coveo for Sitecore search framework were broken on a client's server, and the answer ended up being directly related to crypto security. Here's what happened:
I've been using the built-in code snippets in Visual Studio for years, but for some reason until last week it had never crossed my mind to work out how to create my own. After getting bored writing the same chunk of code too often, I was reminded of the old saying "You should automate any task you have to do more than once". So I decided to have a go at some snippets. Turns out it's both a useful trick to know, and not hard to do:
Have you ever needed to write code that detects if the current computer has an internet connection or not? Having recently tried this, it turns out it's not quite as easy as I expected it would be. So since I've banged my head against the challenge, here's one approach to solving the problem that you might find useful:
