Documentation
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Overview ¶
Package tagset supports creation and manipulation of sets of tags. It does so in a safe and efficient fashion, supporting:
- consistent hashing of tagsets to recognize commonalities - flexible combination of tagsets from multiple sources - immutability to allow re-use of tagsets
The package otherwise presents a fairly abstract API that allows performance optimizations without changing semantics.
Accumulators ¶
HashlessTagsAccumulator and HashingTagsAccumulator both allow building tagsets bit-by-bit, by appending new tags.
HashedTags ¶
The HashedTags type represents an _immutable_ set of tags and associated hashes. It is the primary data structure used to represent a set of tags.
Index ¶
- type HashGenerator
- type HashedTags
- type HashingTagsAccumulator
- func (h *HashingTagsAccumulator) Append(tags ...string)
- func (h *HashingTagsAccumulator) AppendHashed(src HashedTags)
- func (h HashingTagsAccumulator) Copy() []string
- func (h *HashingTagsAccumulator) Dup() *HashingTagsAccumulator
- func (h *HashingTagsAccumulator) Get() []string
- func (h *HashingTagsAccumulator) Hashes() []uint64
- func (h HashingTagsAccumulator) Len() int
- func (h *HashingTagsAccumulator) Less(i, j int) bool
- func (h *HashingTagsAccumulator) Reset()
- func (h *HashingTagsAccumulator) SortUniq()
- func (h *HashingTagsAccumulator) Swap(i, j int)
- func (h *HashingTagsAccumulator) Truncate(len int)
- type HashlessTagsAccumulator
- type TagAccumulator
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type HashGenerator ¶
type HashGenerator struct {
// contains filtered or unexported fields
}
A HashGenerator generates hashes for tag sets, with the property that the hash is invariant over re-ordering of tags and duplicate tags.
This type holds storage for hash operations that can be re-used between operations. It is not threadsafe and the caller must ensure that an instance's Hash method is not called concurrently.
func NewHashGenerator ¶
func NewHashGenerator() *HashGenerator
NewHashGenerator creates a new HashGenerator
func (*HashGenerator) Hash ¶
func (g *HashGenerator) Hash(tb *HashingTagsAccumulator) uint64
Hash calculates the cumulative XOR of all unique tags in the builder. As a side-effect, it sorts and deduplicates the hashes contained in the builder.
type HashedTags ¶
type HashedTags struct {
// contains filtered or unexported fields
}
HashedTags is an immutable slice of pre-hashed tags.
func NewHashedTagsFromSlice ¶
func NewHashedTagsFromSlice(tags []string) HashedTags
NewHashedTagsFromSlice creates a new instance, re-using tags as the internal slice.
func (HashedTags) Copy ¶
func (h HashedTags) Copy() []string
Copy returns a new slice with the copy of the tags
func (HashedTags) Get ¶
func (h HashedTags) Get() []string
Get returns the internal slice.
NOTE: this returns a mutable reference to data in this immutable data structure. It is still used by pkg/tagger/tagstore, but new uses should not be added.
func (HashedTags) Slice ¶
func (h HashedTags) Slice(i, j int) HashedTags
Slice returns a shared sub-slice of tags from t.
type HashingTagsAccumulator ¶
type HashingTagsAccumulator struct {
// contains filtered or unexported fields
}
HashingTagsAccumulator allows to build a slice of tags, including the hashes of each tag.
This type implements TagAccumulator.
func NewHashingTagsAccumulator ¶
func NewHashingTagsAccumulator() *HashingTagsAccumulator
NewHashingTagsAccumulator returns a new empty HashingTagsAccumulator
func NewHashingTagsAccumulatorWithTags ¶
func NewHashingTagsAccumulatorWithTags(tags []string) *HashingTagsAccumulator
NewHashingTagsAccumulatorWithTags return a new HashingTagsAccumulator, initialized with tags.
func (*HashingTagsAccumulator) Append ¶
func (h *HashingTagsAccumulator) Append(tags ...string)
Append appends tags to the builder
func (*HashingTagsAccumulator) AppendHashed ¶
func (h *HashingTagsAccumulator) AppendHashed(src HashedTags)
AppendHashed appends tags and corresponding hashes to the builder
func (HashingTagsAccumulator) Copy ¶
func (h HashingTagsAccumulator) Copy() []string
Copy returns a new slice with the copy of the tags
func (*HashingTagsAccumulator) Dup ¶
func (h *HashingTagsAccumulator) Dup() *HashingTagsAccumulator
Dup returns a complete copy of HashingTagsAccumulator
func (*HashingTagsAccumulator) Get ¶
func (h *HashingTagsAccumulator) Get() []string
Get returns the internal slice
func (*HashingTagsAccumulator) Hashes ¶
func (h *HashingTagsAccumulator) Hashes() []uint64
Hashes returns the internal slice of tag hashes
func (HashingTagsAccumulator) Len ¶
func (h HashingTagsAccumulator) Len() int
Len returns number of tags
func (*HashingTagsAccumulator) Less ¶
func (h *HashingTagsAccumulator) Less(i, j int) bool
Less implements sort.Interface.Less
func (*HashingTagsAccumulator) Reset ¶
func (h *HashingTagsAccumulator) Reset()
Reset resets the size of the builder to 0 without discaring the internal buffer
func (*HashingTagsAccumulator) SortUniq ¶
func (h *HashingTagsAccumulator) SortUniq()
SortUniq sorts and remove duplicate in place
func (*HashingTagsAccumulator) Swap ¶
func (h *HashingTagsAccumulator) Swap(i, j int)
Swap implements sort.Interface.Swap
func (*HashingTagsAccumulator) Truncate ¶
func (h *HashingTagsAccumulator) Truncate(len int)
Truncate retains first n tags in the buffer without discarding the internal buffer
type HashlessTagsAccumulator ¶
type HashlessTagsAccumulator struct {
// contains filtered or unexported fields
}
HashlessTagsAccumulator allows to build a slice of tags, in a context where the hashes for those tags are not useful.
This type implements TagAccumulator.
func NewHashlessTagsAccumulator ¶
func NewHashlessTagsAccumulator() *HashlessTagsAccumulator
NewHashlessTagsAccumulator returns a new empty HashlessTagsAccumulator.
func NewHashlessTagsAccumulatorFromSlice ¶
func NewHashlessTagsAccumulatorFromSlice(data []string) *HashlessTagsAccumulator
NewHashlessTagsAccumulatorFromSlice return a new HashlessTagsAccumulator with the input slice for it's internal buffer.
func (*HashlessTagsAccumulator) Append ¶
func (h *HashlessTagsAccumulator) Append(tags ...string)
Append appends tags to the builder
func (*HashlessTagsAccumulator) AppendHashed ¶
func (h *HashlessTagsAccumulator) AppendHashed(src HashedTags)
AppendHashed appends tags and corresponding hashes to the builder
func (*HashlessTagsAccumulator) Get ¶
func (h *HashlessTagsAccumulator) Get() []string
Get returns the internal slice
func (*HashlessTagsAccumulator) Reset ¶
func (h *HashlessTagsAccumulator) Reset()
Reset resets the size of the builder to 0 without discaring the internal buffer
func (*HashlessTagsAccumulator) SortUniq ¶
func (h *HashlessTagsAccumulator) SortUniq()
SortUniq sorts and remove duplicate in place
type TagAccumulator ¶
type TagAccumulator interface {
// Append the given tags to the tag set
Append(...string)
// Append the tags contained in the given HashedTags instance to the tag set.
AppendHashed(HashedTags)
}
A TagAccumulator accumulates tags. The underlying type will provide a means of getting the resulting tag set.
Source Files