Percolate Query Usage
editPercolate Query Usage
editThe percolate query can be used to match queries stored in an index. The percolate query itself contains the document that will be used as query to match with the stored queries.
In order for the percolate query to work, the index in which your stored queries reside must contain a mapping for documents that you wish to percolate, so that they are parsed correctly at query time.
See the Elasticsearch documentation on percolate query for more details.
In this example, we have a document stored with a query
field that is mapped as a percolator
type. This field
contains a match
query.
Fluent DSL example
editq .Percolate(p => p .Document(Project.Instance) .Field(f => f.Query) )
Object Initializer syntax example
editnew PercolateQuery { Document = Project.Instance, Field = Infer.Field<ProjectPercolation>(f => f.Query) }
Example json output.
{ "percolate": { "document": { "name": "Koch, Collier and Mohr", "state": "BellyUp", "startedOn": "2015-01-01T00:00:00", "lastActivity": "0001-01-01T00:00:00", "leadDeveloper": { "gender": "Male", "id": 0, "firstName": "Martijn", "lastName": "Laarman" }, "location": { "lat": 42.1523, "lon": -80.321 } }, "field": "query" } }
Handling Responses
editresponse.Total.Should().BeGreaterThan(0); response.Hits.Should().NotBeNull(); response.Hits.Count().Should().BeGreaterThan(0); var match = response.Documents.First(); match.Id.Should().Be(PercolatorId); ((IQueryContainer)match.Query).Match.Should().NotBeNull();
Percolate an existing document
editInstead of specifying the source of the document being percolated, the source can also be retrieved from an already stored document. The percolate query will then internally execute a get request to fetch that document.
The required fields to percolate an existing document are:
-
index
in which the document resides -
type
of the document -
field
that contains the query -
id
of the document -
document_type
type / mapping of the document
See the Elasticsearch documentation on percolate query for more details.
Fluent DSL example
editq .Percolate(p => p .Index<Project>() .Id(Project.Instance.Name) .Routing(Project.Instance.Name) .Field(f => f.Query) )
Object Initializer syntax example
editnew PercolateQuery { Index = IndexName.From<Project>(), Id = Project.Instance.Name, Routing = Project.Instance.Name, Field = Infer.Field<ProjectPercolation>(f => f.Query) }
Example json output.
{ "percolate": { "type": "doc", "index": "project", "id": "Durgan LLC", "routing": "Durgan LLC", "field": "query" } }
Handling Responses
editresponse.Total.Should().BeGreaterThan(0); response.Hits.Should().NotBeNull(); response.Hits.Count().Should().BeGreaterThan(0); var match = response.Documents.First(); match.Id.Should().Be(PercolatorId); ((IQueryContainer)match.Query).Match.Should().NotBeNull();
Percolate multiple documents
editThe percolate query can match multiple documents simultaneously with the indexed percolator queries. Percolating multiple documents in a single request can improve performance as queries only need to be parsed and matched once instead of multiple times.
See the Elasticsearch documentation on percolate query for more details.
Fluent DSL example
editq .Percolate(p => p .Documents(Project.Instance, Project.Instance, Project.Instance) .Field(f => f.Query) )
Object Initializer syntax example
editnew PercolateQuery { Documents = new[] { Project.Instance, Project.Instance, Project.Instance }, Field = Infer.Field<ProjectPercolation>(f => f.Query) }
Example json output.
{ "percolate": { "documents": [ { "name": "Koch, Collier and Mohr", "state": "BellyUp", "startedOn": "2015-01-01T00:00:00", "lastActivity": "0001-01-01T00:00:00", "leadDeveloper": { "gender": "Male", "id": 0, "firstName": "Martijn", "lastName": "Laarman" }, "location": { "lat": 42.1523, "lon": -80.321 } }, { "name": "Koch, Collier and Mohr", "state": "BellyUp", "startedOn": "2015-01-01T00:00:00", "lastActivity": "0001-01-01T00:00:00", "leadDeveloper": { "gender": "Male", "id": 0, "firstName": "Martijn", "lastName": "Laarman" }, "location": { "lat": 42.1523, "lon": -80.321 } }, { "name": "Koch, Collier and Mohr", "state": "BellyUp", "startedOn": "2015-01-01T00:00:00", "lastActivity": "0001-01-01T00:00:00", "leadDeveloper": { "gender": "Male", "id": 0, "firstName": "Martijn", "lastName": "Laarman" }, "location": { "lat": 42.1523, "lon": -80.321 } } ], "field": "query" } }
Handling Responses
editresponse.Total.Should().Be(1); response.Hits.Should().NotBeNull(); response.Hits.Count.Should().Be(1); response.Fields.Count.Should().Be(1); var field = response.Fields.ElementAt(0); var values = field.ValuesOf<int>("_percolator_document_slot"); values.Should().Contain(new[] { 0, 1, 2 }); var match = response.Documents.First(); match.Id.Should().Be(PercolatorId); ((IQueryContainer)match.Query).Match.Should().NotBeNull();