I went to a talk this evening given by a lady from the Dutch foundation for burns. She showed a couple of shocking videos, but for me, as a parent of small children, what really caught my attention was the fact that 10 minutes after being poured out, half a cup of tea is sufficient to cause life-threatening burns to a toddler. Be careful out there!

This evening, instead of hanging out at the Microsoft Dev Days Geek Night, I drove home, put the kids to bed, and sat down to figure out how to update my Twitter status from the Windows Powershell. This was inspired by the bash one-liner using curl that I learned about from Peteris Krumins’ blog (recommended). Well, it turns out not to be a one-liner in powershell, but FWIW - here's how!

function tweet([string] $status) {
   #http://blogs.msdn.com/shitals/archive/2008/12/27/9254245.aspx
  [System.Net.ServicePointManager]::Expect100Continue = $false
  try {
    $wc = new-object System.Net.WebClient
    $wc.BaseAddress = "http://twitter.com"
    $wc.Credentials = new-object System.Net.NetworkCredential
    $wc.Credentials.UserName = "Your account name"
    $wc.Credentials.Password = "password"
    $stream = $wc.OpenWrite("statuses/update.xml")
    $writer = new-object System.IO.StreamWriter -ArgumentList $stream
    $writer.Write("status=" + $status) 
  }
  finally {
    $writer.Dispose()
    $stream.Dispose()
    $wc.Dispose()
  }
}

Apparently, I have a noteable namesake; there was a Dominic Cronin who played cricket for Ireland. Who knew?

http://www.cricketeurope4.net/CSTATZ/irelandall/bio/c/cronin_d.html

Back in June, I wrote a blog post in reaction to Udi Dahan's "The fallacy of ReUse". Now Mark Needham has published a blog post with a very similar theme. One interesting insight is that sometimes sharing domain objects can be dangerous, because as he puts it "although we often do have the same domain concepts in different projects, it's quite rare that they mean exactly the same thing".

Definitely worth a read.

Today the official announcement has been made of the awards in SDL's Tridion MVP (Most valued professional) programme.

I'm on the list. I'm now a Tridion MVP. [insert happy-dance here]

I'd like to say I'm surprised and honoured, but as I was on the committee responsible for making the awards, I'll have to settle for simply being honoured. (Of course, I wasn't allowed to vote for myself.) The award is given to those people who have been most visibly involved in community activities in the world of Tridon. This mostly means being willing to share ones knowledge and experience with others, for example on the Tridion technical forum, ideas site or building blocks exchange. Notwithstanding the fact that participating in these activities is a pleasure in itself, I am very pleased to receive the award, and to be counted in the same company as the other MVPs.

I really hope that now as a group we can go on to do even more, and that the whole will prove to be greater than the sum of the parts.

So to my fellow committee members, and to the Tridion community at large; thank you.

In his recent blog posting on XML Namespaces, James Clark questions the universal goodness of namespaces. Of course, there is plenty of goodness there, but he's right to question it. He says the following:

For XML, what is done is done.  As far as I can tell, there is zero interest amongst major vendors in cleaning up or simplifying XML. I have only two small suggestions, one for XML language designers and one for XML tool vendors:

• For XML language designers, think whether it is really necessary to use XML Namespaces. Don’t just mindlessly stick everything in a namespace because everybody else does.  Using namespaces is not without cost. There is no inherent virtue in forcing users to stick xmlns=”…” on the document element.

• For XML vendors, make sure your tool has good support for documents that don’t use namespaces.  For example, don’t make the namespace URI be the only way to automatically find a schema for a document

It's the second point that interests me. During a recent Tridion project, there was a requirement to accept data from an external source as an XML document. I wanted to use a Tridion component to store this data, as this would give me the benefits of XML Schema validation, and controlled publishing. The document didn't have a namespace, although it had a schema. In order to get this to work with Tridion, I had to go to the provider of the document, and get them to add a namespace. Tridion wouldn't allow me to create a schema whose target namespace was empty. It seemed a shame that even when hand-editing the schema (so presumably asserting that I knew what I was about) the system wouldn't let me make this choice.

At the time, I just got the other party to make the change, and went back to more important things. Maybe there's some internal constraint in the way Tridion works that prevents them from supporting this, or maybe it's such an edge case that no-one was ever bothered by it. If the former, then I can't think what the problem would be; there's no reason to abuse the namespace to locate the schema. Tridion's quite happy enough to allow several schemas targetting the same namespace, so what's so special about the "no" namespace? In Tridion components, XML attributes (quite correctly) are in no namespace, but as long as the correct schema gets used for validation, so what?

I suspect it's more likely that this just comes under the "edge case" heading, in which case, perhaps they can improve it in a future release.

A long time ago, I worked in a job where the boss was "pointy-haired", and we habitually referred to some of the manifestations of his pointy-hairedness as "mauve". Why was this? Well it all came about as a reference to a specific Dilbert cartoon. Tioday I followed a link from Raymond Chen and ended up at the Dilbert strip finder. I typed in database (why not mauve?), and the second hit was the cartoon that explains it all. What's not to like?

I saw this mentioned in passing tonight in #gentoo. It's a simple enough idea, but it makes one particular task very easy. When you're stuck behind layers of networking devices, sometimes it's hard to know whether your site is working for people outside your firewalls etc.

http://downforeveryoneorjustme.com/www.dominic.cronin.nl

I don't know exactly when it was that Tridion started shipping the XML Schema files for the content delivery configuration files. For what it's worth, I only really became aware of it within the last few months. In that short time, schema validation has saved my ass at least twice when configuring a Tridion Content Delivery system. What's not to like? Never mind "What's not to like?" - I'll go further. Now that the guys over at Tridion have gone to the trouble of including these files as release assets - it is positively rude of you not to validate your config files.

Being a well-mannered kind of guy, I figured that I'd like to validate my configuration files not just once, but repeatedly. All the time, in fact. Whenever I make a change. The trouble is that the typical server where you find these things isn't loaded down with tools like XML Spy. The last time I validated a config file, it involved copying the offending article over to a file share, and then emailing it to myself on another machine. Not good. Not easy. Not very repeatable.

But enter our new hero, Windows 2008 Server - these days the deployment platform of choice if you want to run Tridion Content Delivery on a Windows box. And fully loaded for bear. At least the kind of bears you can hunt using powershell. Now that I can just reach out with powershell and grab useful bits of the .NET framework, I don't have any excuse any more, or anywhere to hide, so this afternoon, I set to work hacking up something to validate my configuration files. Well - of course, it could be any XML file. Maybe other people will find it useful too.

So to start with - I thought - just do the simplest thing. I needed to associate the xml files with their relevant schemas, and of course, I could have simply done that in the script, but then what if people move things around etc., so I decided that I would put the schemas in a directory on the server, and use XMLSchema-instance attributes to identify which schema belongs with each file.

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="schema.xsd"

OK - so I'd have to edit each of the half-dozen or so configuration files, but that's a one-off job, so not much trouble. The .NET framework's XmlReader can detect this, and use it to locate the correct schema. (although if it isn't correctly specified, you won't see any validation errors even if the file is incorrect. I'll hope to fix that in a later version of my script.)

I created a function in powershell, like this:

# So far this silently fails to catch any problems if the schema locations aren't set up properly
# needs more work I suppose. Until then it can still deliver value if set up correctly
function ValidateXmlFile {
    param ([string]$xmlFile       = $(read-host "Please specify the path to the Xml file"))
    "==============================================================="
    "Validating $xmlFile using the schemas locations specified in it"
    "==============================================================="
    $settings = new-object System.Xml.XmlReaderSettings
    $settings.ValidationType = [System.Xml.ValidationType]::Schema
    $settings.ValidationFlags = $settings.ValidationFlags `
            -bor [System.Xml.Schema.XmlSchemaValidationFlags]::ProcessSchemaLocation
    $handler = [System.Xml.Schema.ValidationEventHandler] {
        $args = $_ # entering new block so copy $_
        switch ($args.Severity) {
            Error {
                # Exception is an XmlSchemaException
                Write-Host "ERROR: line $($args.Exception.LineNumber)" -nonewline
                Write-Host " position $($args.Exception.LinePosition)"
                Write-Host $args.Message
                break
            }
            Warning {
                # So far, everything that has caused the handler to fire, has caused an Error...
                Write-Host "Warning:: Check that the schema location references are joined up properly."
                break
            }
        }
    }
    $settings.add_ValidationEventHandler($handler)
    $reader = [System.Xml.XmlReader]::Create($xmlfile, $settings)
    while($reader.Read()){}
    $reader.Close()
}

With this function in place, all I have to do is have a list of lines like the following:

ValidateXmlFile "C:\Program Files\Tridion\config\cd_instances_conf.xml"
ValidateXmlFile "C:\Program Files\Tridion\config\live\cd_broker_conf.xml"

If I've made typos or whatever, I'll pretty soon find them, and this can easily save hours. My favourite mistake is typing the attributes in lower case. Typically in these config files, attributes begin with a capital letter. Once you've made a mistake like that, trust me, no amount of staring at the code will make it obvious. You can stare straight at it and not see it.

So there you have it - as always - comments or improvements are always welcome, particularly if anyone knows how to get the warnings to show up!

In recent times, SDL Tridion have been putting out marketing videos on their very own YouTube channel. Each one takes a fictitious (or perhaps anonymised) use-case for their products and presents a fairly non-technical view of it by means of animated graphics, with voice-overs in disconcertingly generic varieties of British English. Never mind British, it's English English, of a sort of carefully not-too-posh-but-not-too-common-either, home-counties kind.

It's a bit strange for me. Obviously, I'm not the target audience. The videos are aimed at non-technical people who are not familiar with Tridion. Over the years I've got to know Tridion pretty well, both as a company and as a product suite. From so close up, the videos have an almost surreal aura. The multitudinous mismatches between the marketeers' in-world reality, and my own, leap out at me.

Why British English, when it's a Dutch company, whose biggest growth market is the US? Why this particularly strange variant of British English? (OK - full disclosure here; I'm a Geordie!) Is this the SDL influence, or does this come from US marketeers?

And are the examples real? I'm curious.

And so on....

As for the content, at least the most recent one (SDL Tridion WCM Platform for Syncronizing Online Content) had me jumping up and down in a couple of places. Like this: "... I can always revert back to previous versions of any content. It is important for our compliance department that we have proof of how a web site looked at any date in the past". Talk about a confusing message. Firstly, normal versioning in Tridion is not intended for that, and won't meet that need. They have a separate product called Archive Manager, which could be used to implement a solution for this problem.

Of course, if their marketing department were to put out a message aimed at someone like me, they would almost certainly deserve to be fired on the spot. It just hits my weirdness button. Know what I mean?