LinqToSolr is an intuitive and lightweight C# library designed to enhance Solr queries with the power of Linq. It seamlessly integrates Solr search capabilities into .NET applications, facilitating cleaner and more maintainable code. LinqToSolr is suitable for developing complex search solutions or simplifying query logic.
To install:
dotnet add package LinqToSolr
The library supports a variety of Linq methods, including but not limited to:
Where
First
FirstOrDefault
Select
Contains
Array.Contains(solrField)
StartsWith
EndsWith
GroupBy
Take
Skip
OrderBy
ThenBy
OrderByDescending
ThenByDescending
ToListAsync
AddOrUpdateAsync
DeleteAsync
First, define a model class to represent your Solr document:
public class MyProduct{
public int Id{get;set;}
[LinqToSolrField("username")]
public string Name{get;set}
public string Group{get;set}
[LinqToSolrField("deleted")]
public bool IsDeleted{get;set}
public string[] Tags{get;set;}
[LinqToSolrFieldIgnore]
public string CustomField{}
}
Initialize a configuration class for the service:
var solrConfig = new LinqToSolrConfiguration("http://localhost:8983/") // URL to Solr instance, if solr has different location (not under/solr) set it to http://localhost:8983/somecustomlocation
.MapCoreFor<MyProduct>("MyProductIndex"); // Mapping your model to Solr Index
Instantiate the base service and provide the configuration:
var solrService = new LinqToSolrService(solrConfig);
You may create a custom service that inherits from LinqToSolrService:
public class MyProductService: LinqToSolrService{
private Task<IQueryable<>> IQueryable<MyProduct> IsNotDeleted()
{
return AsQueryable<MyProduct>().Where(x=> !x.IsDeleted);
}
public async Task<ICollection<MyProduct>> GetProductsByIds(params int[] ids)
{
return await IsNotDeleted().Where(x=> ids.Contains(x.Id)).ToListAsync();
}
}
await solrService.AsQueryable<MyProduct>().Where(x => x.Group == "MyGroup1").ToListAsync();
var groupArray = new[] { "MyGroup1", "MyGroup2", "MyGroup3", "MyGroup4" };
var product = await solrService.AsQueryable<MyProduct>().FirstOrDefault(x => x.Id == 123);
var orderedProducts = await solrService.AsQueryable<MyProduct>()
.Where(x => x.Group == "MyGroup1")
.OrderBy(x => x.Id)
.ThenByDescending(x => x.Name)
.ToListAsync();
solrService.AsQueriable<MyProduct>().Where(x=> x.Name.Contains("productName")).ToList();
var array = new[]{"str2", "str3", "str4"};
solrService.AsQueriable<MyProduct>().Where(x=> array.Contains(x.Name)).ToList();
solrService.AsQueriable<MyProduct>().Where(x=> x.Tags.Contains("tag1")).ToList();
await solrService.AsQueriable<MyProduct>().Where(x=> x.Group == "MyGroup1").OrderBy(x=>x.Id).ThenByDescending(x=>x.Name).ToListAsync();
var docs = await solrService.AsQueriable<MyProduct>().ToFacetsAsync(x => x.IsActive) ;
var activeList = docs[x=>x.IsActive]; // bool list of facets
var docs = await solrService.AsQueriable<MyProduct>().Where(x=>x.IsActive).ToFacetsAsync(x => x.Tags) as LinqToSolrFacetDictionary<SolrDocument>; // facets with query for arrays
var tagsList = docs.GetFacet<string[], string>(x => x.Tags);
solrService.AsQueriable<MyProduct>().Where(x=> x.Group == "MyGroup1").Select(x=x.Name).ToList();
solrService.AsQueriable<MyProduct>().Where(x=> x.Group == "MyGroup1").Select(x=x new {x.Name, x.Group}).ToList();
Adding or Updating Documents Add or update documents in a Solr core:
var products = new[] {
new MyProduct { Id = 1, Name = "Product One" },
new MyProduct { Id = 2, Name = "Product Two" },
new MyProduct { Id = 3, Name = "Product Three" }
};
await solrService.AddOrUpdateAsync(products);
Deleting Documents Delete documents by specifying an array of ids:
await solrService.Where(x => x.Id == 123).DeleteAsync<MyProduct>();