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| 1 | +// Copyright 2021 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 | +package collector |
| 14 | + |
| 15 | +import ( |
| 16 | + "encoding/json" |
| 17 | + "fmt" |
| 18 | + "net/http" |
| 19 | + "net/url" |
| 20 | + "path" |
| 21 | + |
| 22 | + "github.com/go-kit/kit/log" |
| 23 | + "github.com/go-kit/kit/log/level" |
| 24 | + "github.com/prometheus/client_golang/prometheus" |
| 25 | +) |
| 26 | + |
| 27 | +var ( |
| 28 | + defaultNodeShardLabels = []string{"node"} |
| 29 | + |
| 30 | + defaultNodeShardLabelValues = func(node string) []string { |
| 31 | + return []string{ |
| 32 | + node, |
| 33 | + } |
| 34 | + } |
| 35 | +) |
| 36 | + |
| 37 | +// Shards information struct |
| 38 | +type Shards struct { |
| 39 | + logger log.Logger |
| 40 | + client *http.Client |
| 41 | + url *url.URL |
| 42 | + |
| 43 | + nodeShardMetrics []*nodeShardMetric |
| 44 | + jsonParseFailures prometheus.Counter |
| 45 | +} |
| 46 | + |
| 47 | +// NodeShard Information per node struct |
| 48 | +type NodeShard struct { |
| 49 | + node string |
| 50 | + shards int64 |
| 51 | +} |
| 52 | + |
| 53 | +type nodeShardMetric struct { |
| 54 | + Type prometheus.ValueType |
| 55 | + Desc *prometheus.Desc |
| 56 | + Value func(shards float64) float64 |
| 57 | + Labels func(node string) []string |
| 58 | +} |
| 59 | + |
| 60 | +// NewShards defines Shards Prometheus metrics |
| 61 | +func NewShards(logger log.Logger, client *http.Client, url *url.URL) *Shards { |
| 62 | + return &Shards{ |
| 63 | + logger: logger, |
| 64 | + client: client, |
| 65 | + url: url, |
| 66 | + |
| 67 | + nodeShardMetrics: []*nodeShardMetric{ |
| 68 | + { |
| 69 | + Type: prometheus.GaugeValue, |
| 70 | + Desc: prometheus.NewDesc( |
| 71 | + prometheus.BuildFQName(namespace, "node_shards", "total"), |
| 72 | + "Total shards per node", |
| 73 | + defaultNodeShardLabels, nil, |
| 74 | + ), |
| 75 | + Value: func(shards float64) float64 { |
| 76 | + return shards |
| 77 | + }, |
| 78 | + Labels: defaultNodeShardLabelValues, |
| 79 | + }}, |
| 80 | + |
| 81 | + jsonParseFailures: prometheus.NewCounter(prometheus.CounterOpts{ |
| 82 | + Name: prometheus.BuildFQName(namespace, "node_shards", "json_parse_failures"), |
| 83 | + Help: "Number of errors while parsing JSON.", |
| 84 | + }), |
| 85 | + } |
| 86 | +} |
| 87 | + |
| 88 | +// Describe Shards |
| 89 | +func (s *Shards) Describe(ch chan<- *prometheus.Desc) { |
| 90 | + ch <- s.jsonParseFailures.Desc() |
| 91 | + |
| 92 | + for _, metric := range s.nodeShardMetrics { |
| 93 | + ch <- metric.Desc |
| 94 | + } |
| 95 | +} |
| 96 | + |
| 97 | +func (s *Shards) getAndParseURL(u *url.URL, data interface{}) error { |
| 98 | + res, err := s.client.Get(u.String()) |
| 99 | + if err != nil { |
| 100 | + return fmt.Errorf("failed to get from %s://%s:%s%s: %s", |
| 101 | + u.Scheme, u.Hostname(), u.Port(), u.Path, err) |
| 102 | + } |
| 103 | + |
| 104 | + defer func() { |
| 105 | + err = res.Body.Close() |
| 106 | + if err != nil { |
| 107 | + _ = level.Warn(s.logger).Log( |
| 108 | + "msg", "failed to close http.Client", |
| 109 | + "err", err, |
| 110 | + ) |
| 111 | + } |
| 112 | + }() |
| 113 | + |
| 114 | + if res.StatusCode != http.StatusOK { |
| 115 | + return fmt.Errorf("HTTP Request failed with code %d", res.StatusCode) |
| 116 | + } |
| 117 | + |
| 118 | + if err := json.NewDecoder(res.Body).Decode(data); err != nil { |
| 119 | + s.jsonParseFailures.Inc() |
| 120 | + return err |
| 121 | + } |
| 122 | + return nil |
| 123 | +} |
| 124 | + |
| 125 | +func (s *Shards) fetchAndDecodeShards() ([]ShardResponse, error) { |
| 126 | + |
| 127 | + u := *s.url |
| 128 | + u.Path = path.Join(u.Path, "/_cat/shards") |
| 129 | + q := u.Query() |
| 130 | + q.Set("format", "json") |
| 131 | + u.RawQuery = q.Encode() |
| 132 | + u.RawPath = q.Encode() |
| 133 | + var sfr []ShardResponse |
| 134 | + err := s.getAndParseURL(&u, &sfr) |
| 135 | + if err != nil { |
| 136 | + return sfr, err |
| 137 | + } |
| 138 | + return sfr, err |
| 139 | +} |
| 140 | + |
| 141 | +// Collect number of shards on each nodes |
| 142 | +func (s *Shards) Collect(ch chan<- prometheus.Metric) { |
| 143 | + |
| 144 | + defer func() { |
| 145 | + ch <- s.jsonParseFailures |
| 146 | + }() |
| 147 | + |
| 148 | + sr, err := s.fetchAndDecodeShards() |
| 149 | + if err != nil { |
| 150 | + _ = level.Warn(s.logger).Log( |
| 151 | + "msg", "failed to fetch and decode cluster settings stats", |
| 152 | + "err", err, |
| 153 | + ) |
| 154 | + return |
| 155 | + } |
| 156 | + |
| 157 | + nodeShards := make(map[string]float64) |
| 158 | + |
| 159 | + for _, shard := range sr { |
| 160 | + if val, ok := nodeShards[shard.Node]; ok { |
| 161 | + nodeShards[shard.Node] = val + 1 |
| 162 | + } else { |
| 163 | + nodeShards[shard.Node] = 1 |
| 164 | + } |
| 165 | + } |
| 166 | + |
| 167 | + for node, shards := range nodeShards { |
| 168 | + for _, metric := range s.nodeShardMetrics { |
| 169 | + ch <- prometheus.MustNewConstMetric( |
| 170 | + metric.Desc, |
| 171 | + metric.Type, |
| 172 | + metric.Value(shards), |
| 173 | + metric.Labels(node)..., |
| 174 | + ) |
| 175 | + } |
| 176 | + } |
| 177 | +} |
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