1// Copyright 2013 The Prometheus Authors 2// Licensed under the Apache License, Version 2.0 (the "License"); 3// you may not use this file except in compliance with the License. 4// You may obtain a copy of the License at 5// 6// http://www.apache.org/licenses/LICENSE-2.0 7// 8// Unless required by applicable law or agreed to in writing, software 9// distributed under the License is distributed on an "AS IS" BASIS, 10// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 11// See the License for the specific language governing permissions and 12// limitations under the License. 13 14package scrape 15 16import ( 17 "github.com/prometheus/prometheus/pkg/labels" 18 "github.com/prometheus/prometheus/storage" 19) 20 21type nopAppendable struct{} 22 23func (a nopAppendable) Appender() (storage.Appender, error) { 24 return nopAppender{}, nil 25} 26 27type nopAppender struct{} 28 29func (a nopAppender) Add(labels.Labels, int64, float64) (uint64, error) { return 0, nil } 30func (a nopAppender) AddFast(labels.Labels, uint64, int64, float64) error { return nil } 31func (a nopAppender) Commit() error { return nil } 32func (a nopAppender) Rollback() error { return nil } 33 34// collectResultAppender records all samples that were added through the appender. 35// It can be used as its zero value or be backed by another appender it writes samples through. 36type collectResultAppender struct { 37 next storage.Appender 38 result []sample 39} 40 41func (a *collectResultAppender) AddFast(m labels.Labels, ref uint64, t int64, v float64) error { 42 if a.next == nil { 43 return storage.ErrNotFound 44 } 45 err := a.next.AddFast(m, ref, t, v) 46 if err != nil { 47 return err 48 } 49 a.result = append(a.result, sample{ 50 metric: m, 51 t: t, 52 v: v, 53 }) 54 return err 55} 56 57func (a *collectResultAppender) Add(m labels.Labels, t int64, v float64) (uint64, error) { 58 a.result = append(a.result, sample{ 59 metric: m, 60 t: t, 61 v: v, 62 }) 63 if a.next == nil { 64 return 0, nil 65 } 66 return a.next.Add(m, t, v) 67} 68 69func (a *collectResultAppender) Commit() error { return nil } 70func (a *collectResultAppender) Rollback() error { return nil } 71