Building your first index

In order to get started with Lucinq, you can simply utilise the NuGet Lucinq package from any .net project

#Building Your First Index

Index building with lucinq is a breeze

Firstly, we must open a folder for indexing - in this case we are going to use the static Open() method off the native lucene FSDirectory object.

var indexFolder = FSDirectory.Open(new DirectoryInfo(GeneralConstants.Paths.BBCIndex));

Now we have the directory to work with, we need to set the analyzer we are going to use:

Analyzer analyzer = new StandardAnalyzer(Version.LUCENE_29);

In order to write to an index, we are required to create ourselves an indexwriter object. Note, these are disposable, so we will wrap it in a using to keep things neat.

using (IndexWriter indexWriter = new IndexWriter(indexFolder, analyzer, IndexWriter.MaxFieldLength.UNLIMITED))
{
// our code goes here
}

string[] rssFiles = Directory.GetFiles(GeneralConstants.Paths.RSSFeed);
foreach (var rssFile in rssFiles)
{
// do something with our rss feed
}

So here is the final sample code:

var indexFolder = FSDirectory.Open(new DirectoryInfo(GeneralConstants.Paths.BBCIndex));
Analyzer analyzer = new StandardAnalyzer(Version.LUCENE_29);
using (IndexWriter indexWriter = new IndexWriter(indexFolder, analyzer, IndexWriter.MaxFieldLength.UNLIMITED))
{
	string[] rssFiles = Directory.GetFiles(GeneralConstants.Paths.RSSFeed);
	foreach (var rssFile in rssFiles)
	{
		var newsArticles = ReadFeed(rssFile);
		newsArticles.ForEach(
			newsArticle => 
				indexWriter.AddDocument
				(
					x => x.AddAnalysedField(BBCFields.Title, newsArticle.Title, true),
					x => x.AddAnalysedField(BBCFields.Description, newsArticle.Description, true),
					x => x.AddAnalysedField(BBCFields.Copyright, newsArticle.Copyright),
					x => x.AddStoredField(BBCFields.Link, newsArticle.Link),
					x => x.AddNonAnalysedField(BBCFields.PublishDate, TestHelpers.GetDateString(newsArticle.PublishDateTime), true))
				);
	}

	indexWriter.Optimize();
	indexWriter.Close();
}

The sample shows a basic index being built from an folder of downloaded rss feeds from the bbc website.