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 Go to latest Published: Feb 12, 2024 License: Apache-2.0 Imports: 24 Imported by: 0

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Index

Constants

View Source 
const (
	// MagicIndex 4 bytes at the head of an index file.
	MagicIndex = 0xBAAAD700
	// HeaderLen represents number of bytes reserved of index for header.
	HeaderLen = 5

	// FormatV1 represents 1 version of index.
	FormatV1 = 1
	// FormatV2 represents 2 version of index.
	FormatV2 = 2
)

Variables

This section is empty.

Functions

func AllPostingsKey 

func AllPostingsKey() (name, value string)

AllPostingsKey returns the label key that is used to store the postings list of all existing IDs.

func ExpandPostings 

func ExpandPostings(p Postings) (res []storage.SeriesRef, err error)

ExpandPostings returns the postings expanded as a slice.

func FindIntersectingPostings 

func FindIntersectingPostings(p Postings, candidates []Postings) (indexes []int, err error)

FindIntersectingPostings checks the intersection of p and candidates[i] for each i in candidates, if intersection is non empty, then i is added to the indexes returned. Returned indexes are not sorted.

func IsEmptyPostingsType 

func IsEmptyPostingsType(p Postings) bool

IsEmptyPostingsType returns true if the postings are an empty postings list. When this function returns false, it doesn't mean that the postings isn't empty (it could be an empty intersection of two non-empty postings, for example).

func ReadPostingsOffsetTable 

func ReadPostingsOffsetTable(bs ByteSlice, off uint64, f func(name, value []byte, postingsOffset uint64, labelOffset int) error) error

ReadPostingsOffsetTable reads the postings offset table and at the given position calls f for each found entry. The name and value parameters passed to f reuse the backing memory of the underlying byte slice, so they shouldn't be persisted without previously copying them. If f returns an error it stops decoding and returns the received error.

Types

type ByteSlice 

type ByteSlice interface {
	Len() int
	Range(start, end int) []byte
}

ByteSlice abstracts a byte slice.

type Decoder 

type Decoder struct {
	LookupSymbol func(context.Context, uint32) (string, error)
}

Decoder provides decoding methods for the v1 and v2 index file format.

It currently does not contain decoding methods for all entry types but can be extended by them if there's demand.

func (*Decoder) LabelNamesOffsetsFor 

func (dec *Decoder) LabelNamesOffsetsFor(b []byte) ([]uint32, error)

LabelNamesOffsetsFor decodes the offsets of the name symbols for a given series. They are returned in the same order they're stored, which should be sorted lexicographically.

func (*Decoder) LabelValueFor 

func (dec *Decoder) LabelValueFor(ctx context.Context, b []byte, label string) (string, error)

LabelValueFor decodes a label for a given series.

func (*Decoder) Postings 

func (dec *Decoder) Postings(b []byte) (int, Postings, error)

Postings returns a postings list for b and its number of elements.

func (*Decoder) Series 

func (dec *Decoder) Series(b []byte, builder *labels.ScratchBuilder, chks *[]chunks.Meta) error

Series decodes a series entry from the given byte slice into builder and chks. Previous contents of builder can be overwritten - make sure you copy before retaining.

type FileWriter 

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

func NewFileWriter 

func NewFileWriter(name string) (*FileWriter, error)

func (*FileWriter) AddPadding 

func (fw *FileWriter) AddPadding(size int) error

AddPadding adds zero byte padding until the file size is a multiple size.

func (*FileWriter) Close 

func (fw *FileWriter) Close() error

func (*FileWriter) Flush 

func (fw *FileWriter) Flush() error

func (*FileWriter) Pos 

func (fw *FileWriter) Pos() uint64

func (*FileWriter) Remove 

func (fw *FileWriter) Remove() error

func (*FileWriter) Write 

func (fw *FileWriter) Write(bufs ...[]byte) error

func (*FileWriter) WriteAt 

func (fw *FileWriter) WriteAt(buf []byte, pos uint64) error

type ListPostings 

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

ListPostings implements the Postings interface over a plain list.

func (*ListPostings) At 

func (it *ListPostings) At() storage.SeriesRef

func (*ListPostings) Err 

func (it *ListPostings) Err() error

func (*ListPostings) Next 

func (it *ListPostings) Next() bool

func (*ListPostings) Seek 

func (it *ListPostings) Seek(x storage.SeriesRef) bool

type MemPostings 

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

MemPostings holds postings list for series ID per label pair. They may be written to out of order. EnsureOrder() must be called once before any reads are done. This allows for quick unordered batch fills on startup.

func NewMemPostings 

func NewMemPostings() *MemPostings

NewMemPostings returns a memPostings that's ready for reads and writes.

func NewUnorderedMemPostings 

func NewUnorderedMemPostings() *MemPostings

NewUnorderedMemPostings returns a memPostings that is not safe to be read from until EnsureOrder() was called once.

func (*MemPostings) Add 

func (p *MemPostings) Add(id storage.SeriesRef, lset labels.Labels)

Add a label set to the postings index.

func (*MemPostings) All 

func (p *MemPostings) All() Postings

All returns a postings list over all documents ever added.

func (*MemPostings) Delete 

func (p *MemPostings) Delete(deleted map[storage.SeriesRef]struct{})

Delete removes all ids in the given map from the postings lists.

func (*MemPostings) EnsureOrder 

func (p *MemPostings) EnsureOrder(numberOfConcurrentProcesses int)

EnsureOrder ensures that all postings lists are sorted. After it returns all further calls to add and addFor will insert new IDs in a sorted manner. Parameter numberOfConcurrentProcesses is used to specify the maximal number of CPU cores used for this operation. If it is <= 0, GOMAXPROCS is used. GOMAXPROCS was the default before introducing this parameter.

func (*MemPostings) Get 

func (p *MemPostings) Get(name, value string) Postings

Get returns a postings list for the given label pair.

func (*MemPostings) Iter 

func (p *MemPostings) Iter(f func(labels.Label, Postings) error) error

Iter calls f for each postings list. It aborts if f returns an error and returns it.

func (*MemPostings) LabelNames 

func (p *MemPostings) LabelNames() []string

LabelNames returns all the unique label names.

func (*MemPostings) LabelValues 

func (p *MemPostings) LabelValues(_ context.Context, name string) []string

LabelValues returns label values for the given name.

func (*MemPostings) SortedKeys 

func (p *MemPostings) SortedKeys() []labels.Label

SortedKeys returns a list of sorted label keys of the postings.

func (*MemPostings) Stats 

func (p *MemPostings) Stats(label string, limit int) *PostingsStats

Stats calculates the cardinality statistics from postings.

func (*MemPostings) Symbols 

func (p *MemPostings) Symbols() StringIter

Symbols returns an iterator over all unique name and value strings, in order.

type Postings 

type Postings interface {
	// Next advances the iterator and returns true if another value was found.
	Next() bool

	// Seek advances the iterator to value v or greater and returns
	// true if a value was found.
	Seek(v storage.SeriesRef) bool

	// At returns the value at the current iterator position.
	// At should only be called after a successful call to Next or Seek.
	At() storage.SeriesRef

	// Err returns the last error of the iterator.
	Err() error
}

Postings provides iterative access over a postings list.

func EmptyPostings 

func EmptyPostings() Postings

EmptyPostings returns a postings list that's always empty. NOTE: Returning EmptyPostings sentinel when Postings struct has no postings is recommended. It triggers optimized flow in other functions like Intersect, Without etc.

func ErrPostings 

func ErrPostings(err error) Postings

ErrPostings returns new postings that immediately error.

func Intersect 

func Intersect(its ...Postings) Postings

Intersect returns a new postings list over the intersection of the input postings.

func Merge 

func Merge(ctx context.Context, its ...Postings) Postings

Merge returns a new iterator over the union of the input iterators.

func NewListPostings 

func NewListPostings(list []storage.SeriesRef) Postings

func Without 

func Without(full, drop Postings) Postings

Without returns a new postings list that contains all elements from the full list that are not in the drop list.

type PostingsStats 

type PostingsStats struct {
	CardinalityMetricsStats []Stat
	CardinalityLabelStats   []Stat
	LabelValueStats         []Stat
	LabelValuePairsStats    []Stat
	NumLabelPairs           int
}

PostingsStats contains cardinality based statistics for postings.

type Range 

type Range struct {
	Start, End int64
}

Range marks a byte range.

type Reader 

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

func NewFileReader 

func NewFileReader(path string) (*Reader, error)

NewFileReader returns a new index reader against the given index file.

func NewReader 

func NewReader(b ByteSlice) (*Reader, error)

NewReader returns a new index reader on the given byte slice. It automatically handles different format versions.

func (*Reader) Close 

func (r *Reader) Close() error

Close the reader and its underlying resources.

func (*Reader) LabelNames 

func (r *Reader) LabelNames(_ context.Context, matchers ...*labels.Matcher) ([]string, error)

LabelNames returns all the unique label names present in the index. TODO(twilkie) implement support for matchers.

func (*Reader) LabelNamesFor 

func (r *Reader) LabelNamesFor(ctx context.Context, ids ...storage.SeriesRef) ([]string, error)

LabelNamesFor returns all the label names for the series referred to by IDs. The names returned are sorted.

func (*Reader) LabelValueFor 

func (r *Reader) LabelValueFor(ctx context.Context, id storage.SeriesRef, label string) (string, error)

LabelValueFor returns label value for the given label name in the series referred to by ID.

func (*Reader) LabelValues 

func (r *Reader) LabelValues(ctx context.Context, name string, matchers ...*labels.Matcher) ([]string, error)

LabelValues returns value tuples that exist for the given label name. It is not safe to use the return value beyond the lifetime of the byte slice passed into the Reader. TODO(replay): Support filtering by matchers.

func (*Reader) Postings 

func (r *Reader) Postings(ctx context.Context, name string, values ...string) (Postings, error)

func (*Reader) PostingsRanges 

func (r *Reader) PostingsRanges() (map[labels.Label]Range, error)

PostingsRanges returns a new map of byte range in the underlying index file for all postings lists.

func (*Reader) Series 

func (r *Reader) Series(id storage.SeriesRef, builder *labels.ScratchBuilder, chks *[]chunks.Meta) error

Series reads the series with the given ID and writes its labels and chunks into builder and chks.

func (*Reader) Size 

func (r *Reader) Size() int64

Size returns the size of an index file.

func (*Reader) SortedLabelValues 

func (r *Reader) SortedLabelValues(ctx context.Context, name string, matchers ...*labels.Matcher) ([]string, error)

SortedLabelValues returns value tuples that exist for the given label name. It is not safe to use the return value beyond the lifetime of the byte slice passed into the Reader.

func (*Reader) SortedPostings 

func (r *Reader) SortedPostings(p Postings) Postings

SortedPostings returns the given postings list reordered so that the backing series are sorted.

func (*Reader) SymbolTableSize 

func (r *Reader) SymbolTableSize() uint64

SymbolTableSize returns the symbol table size in bytes.

func (*Reader) Symbols 

func (r *Reader) Symbols() StringIter

Symbols returns an iterator over the symbols that exist within the index.

func (*Reader) Version 

func (r *Reader) Version() int

Version returns the file format version of the underlying index.

type Stat 

type Stat struct {
	Name  string
	Count uint64
}

Stat holds values for a single cardinality statistic.

type StringIter 

type StringIter interface {
	// Next advances the iterator and returns true if another value was found.
	Next() bool

	// At returns the value at the current iterator position.
	At() string

	// Err returns the last error of the iterator.
	Err() error
}

StringIter iterates over a sorted list of strings.

func NewStringListIter 

func NewStringListIter(s []string) StringIter

NewStringListIter returns a StringIter for the given sorted list of strings.

type Symbols 

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

func NewSymbols 

func NewSymbols(bs ByteSlice, version, off int) (*Symbols, error)

NewSymbols returns a Symbols object for symbol lookups.

func (Symbols) Iter 

func (s Symbols) Iter() StringIter

func (Symbols) Lookup 

func (s Symbols) Lookup(o uint32) (string, error)

func (Symbols) ReverseLookup 

func (s Symbols) ReverseLookup(sym string) (uint32, error)

func (Symbols) Size 

func (s Symbols) Size() int

type TOC 

type TOC struct {
	Symbols           uint64
	Series            uint64
	LabelIndices      uint64
	LabelIndicesTable uint64
	Postings          uint64
	PostingsTable     uint64
}

TOC represents index Table Of Content that states where each section of index starts.

func NewTOCFromByteSlice 

func NewTOCFromByteSlice(bs ByteSlice) (*TOC, error)

NewTOCFromByteSlice return parsed TOC from given index byte slice.

type Writer 

type Writer struct {
	Version int
	// contains filtered or unexported fields
}

Writer implements the IndexWriter interface for the standard serialization format.

func NewWriter 

func NewWriter(ctx context.Context, fn string) (*Writer, error)

NewWriter returns a new Writer to the given filename. It serializes data in format version 2.

func (*Writer) AddSeries 

func (w *Writer) AddSeries(ref storage.SeriesRef, lset labels.Labels, chunks ...chunks.Meta) error

AddSeries adds the series one at a time along with its chunks.

func (*Writer) AddSymbol 

func (w *Writer) AddSymbol(sym string) error

func (*Writer) Close 

func (w *Writer) Close() error

Source Files

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