SolrNet IQueryable provider. Extend SolrNet functionality by adding LINQ to SOLR support for basic methods. Compatible with OData.
To use LINQ with SolrNet you need to have ISolrOperations<TEntity> or even ISolrBasicReadOnlyOperations<TEntity>. By default TEntity should be a type with properties marked with SolrField attribute, however it is not mandatory if you going to set another mapping manager when initializing a query. For instance
public class Product
{
[SolrUniqueKey("id")]
public string Id { get; set; }
[SolrField("cat")]
public ICollection<string> Categories { get; set; }
[SolrField("popularity")]
public decimal? Popularity { get; set; }
}
Once you have solr operations interface, call AsQueryable() extension method to create IQueryable<T>. For instance
var solr = ServiceLocator.Current.GetInstance<ISolrOperations<Product>>();
IQueryable<Product> solrLinq = solr.AsQueryable()
Now you can use supported linq methods.
To get result you can
- Call
ToSolrQueryResultsAsync()orToSolrQueryResults()extensions methods to get normal SolrNet query result
SolrQueryResults<Product> result = solrLinq.Where(p => p.Popularity.HasValue).Take(10).ToSolrQueryResults();
- Trigger result by starting enumeration like any other IQueryable result triggering
Product[] result = solrLinq.Where(p => p.Popularity.HasValue).Take(10).ToArray();
It is possible to combine linq and regular SolrNet QueryOptions and main query. For instance if you need to append facets:
IQueryable<Product> solrLinq = solr.AsQueryable(setup =>
{
// Set q parameter. By default *:* will be used.
// LINQ Where method append fq (Filter Query) to query options and not affect main query
options.MainQuery = new SolrQuery("some query");
// Configure SolrNet QueryOptions.
// This function will be called after applying query options from LINQ
// You can setup options not covered by LINQ, for instance facets
options.SetupQueryOptions = queryOptions =>
{
queryOptions.AddFacets();
};
// override default serializer if needed
options.SolrFieldSerializer = new DefaultFieldSerializer();
// override default mapping manager if needed
options.MappingManager = new AttributesMappingManager();
});
- Order by field
Product[] result = solrLinq.OrderBy(p => p.Price).ThenBy(p => p.Id).ToArray();
- Order by functions (not all of SOLR functions currently supported)
Product[] result = solrLinq.OrderBy(p => Math.Pow(p.Price,3) + 1).ToArray();
- Simple comparison
// result fq
// price:{12 TO *}
Product[] result = solrLinq.Where(p => p.Price > 12).ToArray();
- Not equal
// result fq
// (*:* NOT id:(qwe))
Product[] result = solrLinq.Where(p => p.Id != "qwe").ToArray();
- Conditional expressions
// result fq
// (popularity:{7 TO *} OR ((*:* NOT popularity:[* TO *]) AND price:{7 TO *}))
Product[] result = solrLinq.Where(p => (p.Popularity != null ? p.Popularity.Value : p.Price) > 7).ToArray();
- Contains() method
// result fq
// (price:((1) OR (2) OR (3)))
List<decimal> list = new List<decimal> {1, 2, 3};
Product[] result = solrLinq.Where(p => list.Contains(p.Price)).ToArray();
- Any() method
// result fq
// cat:(qwe)
Product[] result = solrLinq.Where(p => p.Categories.Any(s => s == "qwe")).ToArray();
- Anonymous and regular types with fields, pseudo field, functions and transformers
var result = solrLinq.Select(p =>
new {
p.Id,
p.Categories,
Qwe = Math.Pow(2,2), // evaluated locally
Next = new Product2 {Id = p.Id} // evaluated locally after selecting required info from solr
ValStr = SolrExpr.Transformers.Value("qwe"), // value transformer evaluated in solr
Score= SolrExpr.Fields.Score() // score pseudo field evaluated in solr
}).OrderBy(arg => arg.Score) // allowed to use expressions evaluated in solr for ordering
.ToSolrQueryResults();
- Combine Select with other methods
var result = solrLinq
.Where(p => p.Id != null)
.Select(p => new {p.Id, p.Price, p.Categories, Score= SolrExpr.Fields.Score()})
.Where(arg => arg.Categories.Any(s => s == "electronics"))
.OrderBy(arg => arg.Id).ThenBy(arg=>arg.Score)
.Select(arg => new {arg.Id})
.FirstOrDefault(arg2 => arg2.Id != null);
- Top
- Skip
- Any
- AnyAsync
- Count
- CountAsync
- LongCount
- LongCountAsync
- First
- FirstAsync
- FirstOrDefault
- FirstOrDefaultAsync
- Single
- SingleAsync
- SingleOrDefault
- SingleOrDefaultAsync
Cast to interface and get SolrQueryResults object of interface type
SolrQueryResults<IProduct> result = solrLinq
.Where(p => p.Id != null)
.Cast<IProduct>
.ToSolrQueryResults();