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ElasticSearch Head-Only Plugins

If you search for howtos on elasticsearch plugin development, you will likely find a couple of inroductions  to the subject , which go on about Maven, .jar files, XML configuration, and some other details.  However, sometimes rather than a true server-side plugin, all you want to do is slap some HTML UI on top of some ES query results.  Well, it turns out that ES will happily serve any  static content that is present in its plugin/[pluginname]/_site directory.  Furthermore, it will serve the index.html file from the _site directory as the default document for the plugin url ( http://esserver:9200/_plugin/[pluginname] ).   This is, in fact, how plugins like the ubiquitous  elasticsearch-head  plugin work.  It is a front-end for ES and does not require server-side interactions. It's debatable whether a Head-Only piece of code like should  be called a plugin, since you can easily build the same functionality entirely externally, served ...
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NServiceBus subscription storage

In a production deployment, publishers persist their subscriber information for two reasons: 1. A scaled-out logical publisher (say, a load-balanced web service that needs to publish events) consists of multiple physical publishers, which all need to have the same subscriber list. 2. If a physical publisher goes down and comes back up, it needs to be able to rehydrate its subscriber list without the subscribers needing to re-send their initialization messages.
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NServiceBus distributor configuration

Technical notes from figuring out how to deploy NServiceBus in a distributed environment, beyond the simple development setups: 1. In a pub-sub scenario, distributors do not need any configuration specific to the publisher they are distributing for, or the subscribers they are distributing to. The configuration they do need is to mainly to define unique queue names for the queues that the distributor owns: NServiceBus.Distributor.dll.config: <add key="DataInputQueue" value="MyDistributorDataInputQueue" /> <add key="ControlInputQueue" value="MyDistributorControlQueue" /> <add key="ErrorQueue" value="MyEnterpriseErrorQueue@machine" /> <add key="StorageQueue" value="MyDistributorStorageQueue" /> At runtime, the subscriber contacts the distributor, sending it a subscription message that includes the publisher's address and the subscription message type. This makes the distribu...
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WCF has its own web server!

I have dabbled a little bit in WCF, but had always been under the impression that services which implement HTTP endpoints needed to be hosted in IIS. Not so! Apparently, the WCF runtime has its own web server built in. I just wrote a service which is hosted in a Windows Service, specified a WSHttpBinding, and WCF took care of the rest.
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Web Deployment Projects targeting x64

I am working on an ASP.NET web application which has mixed-mode C++/CLI dependencies that call out to pure unmanaged DLLs. A new requirement is a 64-bit version of the application (it runs fine on Win64 in a IIS 32-bit app pool, but since 32-bit mode is an all-or-nothing proposition, it was decided we need a true 64 bit app.) I ran into a problem getting the Visual Studio Web Deployment Project to compile my app. It seems that aspnet_compiler.exe loads all of the dependencies during compilation, and the 32 bit compiler cannot load the 64 bit images (you get a "bad image format" error.) This is true even on Win64 build machines that have the .NET Framework64 (and therefore the 64-bit aspnet_compiler.exe) After a bit of spelunking through the .wdproj, I found that a relatively simple change to the MSBUILD file shipped with the WD project will allow this to work out. It simply forces MSBUILD to use the 64 bit compiler if the $(Platform) variable is set to "x64" Here is...
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UI Automation for Developers

I'm currently working on a Wix 3.0-based installer with about 6 different wizard dialogs. Testing installers is a lot of work, because it is difficult to arrange for only the part of the installer you are interested in to run. I found myself filling out credentials, picking websites, etc. over and over. The QA organzation at my company uses AutoIt3 , a free UI automation tool with a VB-like syntax, to do UI automation for Windows GUIs, and I thought I would check it out and see if I could quickly record a macro which would get me all the way through the UI sequence of my installer. Sure enough, it was as easy as this: Download and install AutoIt3 Make sure to get the full SciTe editor for AutoIt (it is not included in the basic install). This editor includes a tool called AU3Record which will record your mouse and keyboard interactions with a Windows app and generate the AutoIt script to replay those actions. The tool is installed to: c:\Program Files\AutoIt3\SciTE\ScriptWriter\Au...
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Unintuitive error in msi log when DTF is misconfigured

Took me a little headscratching to figure this one out. I was getting an error from my installer with the following text: MSI (s) (A8:50) [14:27:03:446]: Product: MyProduct -- Error 1723. There is a problem with this Windows Installer package. A DLL required for this install to complete could not be run. Contact your support personnel or package vendor. Action CA_ConfigFile_Install_Immediate, entry: CA_ConfigFile_Install_Immediate, library: C:\WINDOWS\Installer\MSI51BF.tmp The problem was not really that a DLL was missing, but that I had a typo in my <CustomAction DllEntry="xxx"> declaration. The typo caused a mismatch between the DllEntry value and the actual name of the .NET method implementing the [CustomAction].
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