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Documentation

Index

• Variables
• type BloomFiltersController
  • func New(size int, opts ...option) *BloomFiltersController
  • func (bf *BloomFiltersController) Acquire() []uint64
  • func (bf *BloomFiltersController) Add(data []uint64, s []byte)
  • func (bf *BloomFiltersController) Debug(data []uint64, v []byte) string
  • func (bf *BloomFiltersController) MayContain(data []uint64, s []byte) bool
  • func (bf *BloomFiltersController) PreAllocate(n int)
  • func (bf *BloomFiltersController) Release(v []uint64)
  • func (bf *BloomFiltersController) Size() int
• type Index
  • func NewIndex(nParallel int, verifier Verifier, opts ...option) *Index
  • func (idx *Index) Add(id uint64, searchTerms [][]byte)
  • func (idx *Index) Lookup(searchTerms [][]byte) ([]uint64, error)
• type Options
• type SearchEngine
  • func NewSearchEngine[T, Q any](termsExtractor TermsExtractor[T, Q], verifier Verifier, indexOptions ...option) *SearchEngine[T, Q]
  • func (se *SearchEngine[T, Q]) Index(id uint64, input T)
  • func (se *SearchEngine[T, Q]) Lookup(query Q) ([]uint64, error)
• type TermsExtractor
• type Verifier

Variables

var WithCustomMapper = func(f func(size, seed int) func([]byte) int) option {
	return func(opts *Options) {
		opts.CreateMapperFunc = f
	}
}

var WithErrorRate = func(float64) option {
	panic("not implemented")
}

WithErrorRate - calculate NMappers using expectations for number of elements inserted and false-positive error rate. See https://en.wikipedia.org/wiki/Bloom_filter#Probability_of_false_positives

var WithNMappers = func(nMappers int) option {
	return func(opts *Options) {
		opts.NMappers = nMappers
	}
}

Types

type BloomFiltersController

type BloomFiltersController struct {
	// contains filtered or unexported fields
}

func New

func New(size int, opts ...option) *BloomFiltersController

func (*BloomFiltersController) Acquire

func (bf *BloomFiltersController) Acquire() []uint64

Acquire - get a slice from pool / create new to use as a storage for a bloom filter.

func (*BloomFiltersController) Add

func (bf *BloomFiltersController) Add(data []uint64, s []byte)

Add - encode string into data

func (*BloomFiltersController) Debug

func (bf *BloomFiltersController) Debug(data []uint64, v []byte) string

Debug - print current data state in binary form and highlight bits, that represent value v.

func (*BloomFiltersController) MayContain

func (bf *BloomFiltersController) MayContain(data []uint64, s []byte) bool

MayContain - check that data [possibly] contains s

func (*BloomFiltersController) PreAllocate

func (bf *BloomFiltersController) PreAllocate(n int)

PreAllocate - pre-create several slices and put them into pool in advance to make Acquire() faster

func (*BloomFiltersController) Release

func (bf *BloomFiltersController) Release(v []uint64)

Release - free v for future use

func (*BloomFiltersController) Size

func (bf *BloomFiltersController) Size() int

Size - number of bits

type Index

type Index struct {
	// contains filtered or unexported fields
}

Index - search index implementation using Bloom filters.

func NewIndex

func NewIndex(nParallel int, verifier Verifier, opts ...option) *Index

func (*Index) Add

func (idx *Index) Add(id uint64, searchTerms [][]byte)

func (*Index) Lookup

func (idx *Index) Lookup(searchTerms [][]byte) ([]uint64, error)

type Options

type Options struct {
	CreateMapperFunc func(size, seed int) func([]byte) int
	NMappers         int
}

type SearchEngine

type SearchEngine[T, Q any] struct {
	// contains filtered or unexported fields
}

SearchEngine performs indexing and lookup operations for objects of type T

func NewSearchEngine

func NewSearchEngine[T, Q any](
	termsExtractor TermsExtractor[T, Q],
	verifier Verifier,
	indexOptions ...option,
) *SearchEngine[T, Q]

func (*SearchEngine[T, Q]) Index

func (se *SearchEngine[T, Q]) Index(id uint64, input T)

func (*SearchEngine[T, Q]) Lookup

func (se *SearchEngine[T, Q]) Lookup(query Q) ([]uint64, error)

type TermsExtractor

type TermsExtractor[T, Q any] interface {
	ExtractValueTerms(input T) [][]byte
	ExtractQueryTerms(input Q) [][]byte
}

type Verifier

type Verifier interface {
	Verify(id uint64, terms [][]byte) (bool, error)
}