98 lines
2.9 KiB
Go
98 lines
2.9 KiB
Go
// Copyright (c) Bartłomiej Płotka @bwplotka
|
|
// Licensed under the Apache License 2.0.
|
|
|
|
// Copyright 2024 Google LLC
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// https://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
// Copyright 2024 Prometheus Team
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package writev2
|
|
|
|
// SymbolsTable implements table for easy symbol use.
|
|
type SymbolsTable struct {
|
|
strings []string
|
|
symbolsMap map[string]uint32
|
|
}
|
|
|
|
// NewSymbolTable returns a symbol table.
|
|
func NewSymbolTable() SymbolsTable {
|
|
return SymbolsTable{
|
|
// Empty string is required as a first element.
|
|
symbolsMap: map[string]uint32{"": 0},
|
|
strings: []string{""},
|
|
}
|
|
}
|
|
|
|
// Symbolize adds (if not added before) a string to the symbols table,
|
|
// while returning its reference number.
|
|
func (t *SymbolsTable) Symbolize(str string) uint32 {
|
|
if ref, ok := t.symbolsMap[str]; ok {
|
|
return ref
|
|
}
|
|
ref := uint32(len(t.strings))
|
|
t.strings = append(t.strings, str)
|
|
t.symbolsMap[str] = ref
|
|
return ref
|
|
}
|
|
|
|
// SymbolizeLabels symbolize Prometheus labels.
|
|
func (t *SymbolsTable) SymbolizeLabels(lbls []string, buf []uint32) []uint32 {
|
|
result := buf[:0]
|
|
for i := 0; i < len(lbls); i += 2 {
|
|
off := t.Symbolize(lbls[i])
|
|
result = append(result, off)
|
|
off = t.Symbolize(lbls[i+1])
|
|
result = append(result, off)
|
|
}
|
|
return result
|
|
}
|
|
|
|
// Symbols returns computes symbols table to put in e.g. Request.Symbols.
|
|
// As per spec, order does not matter.
|
|
func (t *SymbolsTable) Symbols() []string {
|
|
return t.strings
|
|
}
|
|
|
|
// Reset clears symbols table.
|
|
func (t *SymbolsTable) Reset() {
|
|
// NOTE: Make sure to keep empty symbol.
|
|
t.strings = t.strings[:1]
|
|
for k := range t.symbolsMap {
|
|
if k == "" {
|
|
continue
|
|
}
|
|
delete(t.symbolsMap, k)
|
|
}
|
|
}
|
|
|
|
// DesymbolizeLabels decodes label references, with given symbols to labels.
|
|
func DesymbolizeLabels(labelRefs []uint32, symbols, buf []string) []string {
|
|
result := buf[:0]
|
|
for i := 0; i < len(labelRefs); i += 2 {
|
|
result = append(result, symbols[labelRefs[i]], symbols[labelRefs[i+1]])
|
|
}
|
|
return result
|
|
}
|