Archive September 2010:

Accept UTF-8 characters using Solr and Tomcat

• Sep 29th, 2010
• 0 comments
• Solr

If you use Solr and have a search query including an UTF-8 character, like Swedish åäö, you have to turn on the correct encoding for Apache Tomcat. You do this by simply adding URIEncoding="UTF-8" to the appropriate connector in Tomcat's server.xml file (normally located in the Tomcat conf folder).

Here's the complete code snippet to get UTF-8 characters working with Solr search:

<Connector port="8983" protocol="HTTP/1.1"
	connectionTimeout="20000"
	redirectPort="8443"
	URIEncoding="UTF-8" />

You can also read about URI Charset Config in the Solr documentation.

Related post: Get started using Solr for search in ASP.NET

What to do when Visual Studio templates are missing

• Sep 21st, 2010
• 0 comments
• Visual Studio

I recently stumbled upon a problem where some Visual Studio templates wasn't available when I choose Add new item in Visual Studio.

I needed to generate some LINQ to SQL classes, but the Data alternative wasn't there.

After some searching, here's what solved the problem:

For Visual Studio 2010, find the VS command prompt (in the start menu), right click it and choose 'Run as administrator'. Execute this command:

devenv.exe /vsinstalltemplates

You won't be noticed if anything succeeds or fails, but you should now have the appropriate Visual Studio templates available in the Add new item menu.

For Visual Studio 2008, I solved the problem by re-installing Visual Studio 2008 Service Pack 1.

Also, you can have a look in the C:\Program Files (x86)\Microsoft Visual Studio 10.0\Common7\IDE\ItemTemplates folder to see what's missing. You can even copy zip files from other Visual Studio installations to the folders here and execute the above command for Visual Studio 2010, and get it working.

Also - there's a difference when adding files in Solution Explorer, compared to through the File menu.

Here are some blog posts and stack overflow posts that helped me:

• Visual Studio 2008 SP1 ADO.NET Entity Data Model template not found
• Visual Studio 2010 Make and Install Templates
• Missing templates in Visual Studio installed templates

Get Started Using Solr for Search with ASP.NET

• Sep 21st, 2010
• 7 comments
• ASP.NET, Solr

Solr is an advanced search coming from Apache's Lucene project. Thanks to SolrNet, a .NET library for Solr, it is quite convenient to use Solr for search in ASP.NET. I'll show you how. (You can also download the sample app right off, if you'd like to)

Install Apache Tomcat and Solr

First of all, make sure you get the latest version of Apache Tomcat and Solr. (I installed Tomcat 7 and Solr 1.4.1 (zip version) as of September 2010.)

Tomcat installation

When installing Tomcat, make sure to remember the port you specify (normal for Solr is 8983). After installation, the Apache Tomcat Properties window should popup. If not, find Configure Tomcat in the start menu and make sure the web server's started. If it's started, you should find the default Tomcat startpage if you browse to http://localhost:8983.

Solr installation

Before you install Solr, stop the Tomcat web server (through the Configure Tomcat window).

When you've downloaded the Solr zip file (make sure it's the zip version!), unzip the archive and find the dist folder. In the dist folder, find the apache-solr-1.4.1.war file and copy it to C:\Program Files\Apache Software Foundation\Tomcat 7.0\webapps, renaming it to solr.war.

Now, we also need to create the Solr folder, which will host our Solr configuration files, indexes and so on. I created C:\Solr. You'll also need to copy the contents of the apache-solr-1.4.1\example\solr folder to your newly created Solr folder. When you're done, you should at least have the bin and conf folder.

Finally, we need to tell Tomcat where our Solr folder is located. Open up the Configure Tomcat window, navigate to the Java tab and add this row to Java Options:

-Dsolr.solr.home=c:\solr

It should look like this:

Now, you should first start the web server and then be able to navigate to http://localhost:8983/solr. Installation and basic configuration done!

Quick look at the configuration files

The Solr configuration files are important - you will use them to tell Solr what should be indexed and not. The most important config files are schema.xml and solrconfig.xml. These are located in the C:\Solr\conf folder.

Easier use of Solr with the SolrNet library

SolrNet is a great .NET library for Solr, making it all easier. Download assemblies (and samples) on the SolrNet Google Code page.

Sample ASP.NET app with SolrNet for download

I've developed a sample web application for you, using SolrNet for search in ASP.NET.

Basically, you've got some data in the SQL Server database and use SolrNet to find items in the search index and present all you want from the database.

Here's what you should know:

• Map fields to Solr using attributes (Player.cs in the classes folder)
• This is sample code, not everything might be suitable for a production environment
• You should use Linq to Sql, NHibernate or similar for better scaling and easier data access

Download the sample Solr app

I'd like to thank A. Friedman for his contribution to the Solr and ASP.NET world. Here's his great blog post on Solr and SolrNet.

Code snippets using SolrNet

Here's some code snippets from my Solr app. You can find them in the source code, although I found it being a good idea to post code for a couple of common actions using Solr and SolrNet for search.

Search the index and bind to Repeater:

var search = new DefaultSearcher()
	.Search(query, 10, 1);

rptResults.DataSource = search.Result;
rptResults.DataBind();

Re-index all data:

new SolrBaseRepository.Instance<Player>().Start();
			
var solr = ServiceLocator.Current.GetInstance<ISolrOperations<Player>>();
var players = new PlayerRepository().GetPlayers();

solr.Add(players);
solr.Commit();

Remove from index:

new SolrBaseRepository.Instance<Player>().Start();

var solr = ServiceLocator.Current.GetInstance<ISolrOperations<Player>>();
var specificPlayer = new PlayerRepository().GetPlayer(id);

solr.Delete(specificPlayer);
solr.Commit();

Adding multiple fields to the search index

By standard, Solr lets you index one field only, thanks to the defaultSearchField in schema.xml. It's easy to turn on indexing of multiple fields though, using copyField and an additional field which takes multi values.

What you have to do is to edit schema.xml a bit:

1. Setup the fields you want to get indexed, using field.
2. Create an additional field called "text", setting its multiValued property to true.
3. Use copyField to copy data to this additional field.
4. Use this additional field, "text", as the defaultSearchField.

<fields>
	<field name="id" type="int" indexed="true" stored="true" required="true" /> 
	<field name="firstname" type="text" indexed="true" stored="false" required="false" /> 
	<field name="lastname" type="text" indexed="true" stored="false" required="false" />
	<field name="text" type="text" indexed="true" stored="false" multiValued="true" />
</fields>
<copyField source="firstname" dest="text" />
<copyField source="lastname" dest="text" />
<uniqueKey>id</uniqueKey>
<defaultSearchField>text</defaultSearchField>
<solrQueryParser defaultOperator=uot;AND" /> 

Debugging Solr

If you encounter any problems with Solr, try this to get it working:

• Turn off elevate.xml handler (comment appropriate lines in solrconfig.xml).
• Case sensitive configuration files - make sure you spell copyField, multiValued etc correctly.
• In solrconfig.xml, make sure you use matching data types to those you've defined in your ASP.NET app.

More Solr

Solr is really powerful and gives you a lot of options. I recommend the Solr Wiki for more information on what actually is possible.

Save time using Ninite when installing applications!

• Sep 13th, 2010
• 0 comments
• Utilities

A while ago I wrote a post on my favourite Windows tools. Those tools are still my favourites, although I've found a much more efficient way of installing them.

Using Ninite.com makes it all so much easier.

You get a set of applications in different categories, just tick those ones you want, download an installer and then Ninite does the rest. Couldn't be easier!

No more manual installation of a lot of different applications!