sslobodr | d046be8 | 2019-01-16 10:02:22 -0500 | [diff] [blame^] | 1 | // Copyright 2018 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 | |
| 14 | package internal |
| 15 | |
| 16 | import ( |
| 17 | "sort" |
| 18 | |
| 19 | dto "github.com/prometheus/client_model/go" |
| 20 | ) |
| 21 | |
| 22 | // metricSorter is a sortable slice of *dto.Metric. |
| 23 | type metricSorter []*dto.Metric |
| 24 | |
| 25 | func (s metricSorter) Len() int { |
| 26 | return len(s) |
| 27 | } |
| 28 | |
| 29 | func (s metricSorter) Swap(i, j int) { |
| 30 | s[i], s[j] = s[j], s[i] |
| 31 | } |
| 32 | |
| 33 | func (s metricSorter) Less(i, j int) bool { |
| 34 | if len(s[i].Label) != len(s[j].Label) { |
| 35 | // This should not happen. The metrics are |
| 36 | // inconsistent. However, we have to deal with the fact, as |
| 37 | // people might use custom collectors or metric family injection |
| 38 | // to create inconsistent metrics. So let's simply compare the |
| 39 | // number of labels in this case. That will still yield |
| 40 | // reproducible sorting. |
| 41 | return len(s[i].Label) < len(s[j].Label) |
| 42 | } |
| 43 | for n, lp := range s[i].Label { |
| 44 | vi := lp.GetValue() |
| 45 | vj := s[j].Label[n].GetValue() |
| 46 | if vi != vj { |
| 47 | return vi < vj |
| 48 | } |
| 49 | } |
| 50 | |
| 51 | // We should never arrive here. Multiple metrics with the same |
| 52 | // label set in the same scrape will lead to undefined ingestion |
| 53 | // behavior. However, as above, we have to provide stable sorting |
| 54 | // here, even for inconsistent metrics. So sort equal metrics |
| 55 | // by their timestamp, with missing timestamps (implying "now") |
| 56 | // coming last. |
| 57 | if s[i].TimestampMs == nil { |
| 58 | return false |
| 59 | } |
| 60 | if s[j].TimestampMs == nil { |
| 61 | return true |
| 62 | } |
| 63 | return s[i].GetTimestampMs() < s[j].GetTimestampMs() |
| 64 | } |
| 65 | |
| 66 | // NormalizeMetricFamilies returns a MetricFamily slice with empty |
| 67 | // MetricFamilies pruned and the remaining MetricFamilies sorted by name within |
| 68 | // the slice, with the contained Metrics sorted within each MetricFamily. |
| 69 | func NormalizeMetricFamilies(metricFamiliesByName map[string]*dto.MetricFamily) []*dto.MetricFamily { |
| 70 | for _, mf := range metricFamiliesByName { |
| 71 | sort.Sort(metricSorter(mf.Metric)) |
| 72 | } |
| 73 | names := make([]string, 0, len(metricFamiliesByName)) |
| 74 | for name, mf := range metricFamiliesByName { |
| 75 | if len(mf.Metric) > 0 { |
| 76 | names = append(names, name) |
| 77 | } |
| 78 | } |
| 79 | sort.Strings(names) |
| 80 | result := make([]*dto.MetricFamily, 0, len(names)) |
| 81 | for _, name := range names { |
| 82 | result = append(result, metricFamiliesByName[name]) |
| 83 | } |
| 84 | return result |
| 85 | } |