Vultus.Search 0.0.7

Vultus Search

Simple, lightweight, in-memory search index

Overview

Vultus is a lightweight search index for .NET, using the concept of indexes over an in-memory key-value store i.e. a Dictionary<Key, Value>.

Out of the box it supports a property field indexer, allowing you to create property value buckets that you can easily filter on.

You can add your own custom Indexers by implementing the IIndexer interface.

Installation

Vultus is available as a NuGet package. You can install it using the NuGet Package Console window:

PM> Install-Package Vultus.Search

Usage

Creating and populating an index

var index = new Index<string, MyObject>(x => x.Key);

var items = new List<MyObject> {
  new MyObject { Key = "item1", Property = "property1" },
  new MyObject { Key = "item2", Property = "property2" }
};

index.Update(items);

Adding a field indexer and filtering

// Add indexer for "Property"
var indexByProp = index.AddIndex("MyPropIndex", x => x.Property);

// Filter on the indexer will return a list of matching keys
var keys = indexByProp.Filter("property1");

// We can then lookup our values from the index using the keys
var items = index.Filter(keys);

Filtering over multiple indexers

// Add some indexers for titles and UK counties
var indexByTitle = index.AddIndex("Title", x => x.Title); // Mrs, Mr, Miss, Ms
var indexByCounty = index.AddIndex("County", x => x.County); // London, Yorkshire, Merseyside, Devon etc.

// Find matches in our indexers
var titles = indexByTitle.Filter("Ms");
var counties = indexByCounty.Filter("London");

// Now lookup items where the result is both a match on the title and the county i.e. Ms and London
var items = index.Filter(titles.Intersect(counties));

License

Distributed under the MIT License. See LICENSE for more information.

Acknowledgments

Inspired by the day job and the following articles and repositories:

• Indexer - Index large collections by different keys on memory or disk
• Multiple indexes over an in memory collection for faster search
• Indexing In-Memory Collections For Blazing Fast Access
  • CodexMicroORM - Package used in above blog