/
cache.go
185 lines (147 loc) · 4.54 KB
/
cache.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
package convert
import (
"sync"
"time"
"github.com/prometheus/common/model"
"github.com/prometheus/prometheus/model/exemplar"
"github.com/prometheus/prometheus/model/histogram"
"github.com/prometheus/prometheus/model/labels"
"github.com/prometheus/prometheus/model/metadata"
"github.com/prometheus/prometheus/model/timestamp"
"github.com/prometheus/prometheus/storage"
)
// memorySeries is an in-memory series mapped from an OpenTelemetry Collector
// data point.
type memorySeries struct {
// We shouldn't need an RWMutex here because there should only ever be
// exactly one goroutine for each memory series, since each series is
// intended to be unique.
sync.Mutex
labels labels.Labels // Labels used for writing.
metadata map[string]string // Extra (optional) metadata used for conversion.
id storage.SeriesRef // id returned by storage.Appender.
timestamp time.Time // Timestamp used for out-of-order detection.
lastSeen time.Time // Timestamp used for garbage collection.
value float64 // Value used for writing.
}
func newMemorySeries(metadata map[string]string, labels labels.Labels) *memorySeries {
return &memorySeries{
metadata: metadata,
labels: labels,
}
}
// Metadata returns a metadata value by key.
func (series *memorySeries) Metadata(key string) string {
if series.metadata == nil {
return ""
}
return series.metadata[key]
}
// Timestamp returns the current timestamp of this series.
func (series *memorySeries) Timestamp() time.Time {
series.Lock()
defer series.Unlock()
return series.timestamp
}
// SetTimestamp updates the current timestamp of this series.
func (series *memorySeries) SetTimestamp(newTime time.Time) {
// TODO(rfratto): does this need to be a CAS-style function instead?
series.Lock()
defer series.Unlock()
series.timestamp = newTime
}
// LastSeen returns the timestamp when this series was last seen.
func (series *memorySeries) LastSeen() time.Time {
series.Lock()
defer series.Unlock()
return series.lastSeen
}
// Ping updates the last seen timestamp of this series.
func (series *memorySeries) Ping() {
series.Lock()
defer series.Unlock()
series.lastSeen = time.Now()
}
// Value gets the current value of this series.
func (series *memorySeries) Value() float64 {
series.Lock()
defer series.Unlock()
return series.value
}
// SetValue updates the current value of this series.
func (series *memorySeries) SetValue(newValue float64) {
// TODO(rfratto): does this need to be a CAS-style function instead?
series.Lock()
defer series.Unlock()
series.value = newValue
}
func (series *memorySeries) WriteTo(app storage.Appender, ts time.Time) error {
series.Lock()
defer series.Unlock()
newID, err := app.Append(series.id, series.labels, timestamp.FromTime(ts), series.value)
if err != nil {
return err
}
if newID != series.id {
series.id = newID
}
return nil
}
func (series *memorySeries) WriteExemplarsTo(app storage.Appender, e exemplar.Exemplar) error {
series.Lock()
defer series.Unlock()
if _, err := app.AppendExemplar(series.id, series.labels, e); err != nil {
return err
}
return nil
}
func (series *memorySeries) WriteNativeHistogramTo(app storage.Appender, ts time.Time, h *histogram.Histogram, fh *histogram.FloatHistogram) error {
series.Lock()
defer series.Unlock()
if _, err := app.AppendHistogram(series.id, series.labels, timestamp.FromTime(ts), h, fh); err != nil {
return err
}
return nil
}
type memoryMetadata struct {
sync.Mutex
// ID returned by the underlying storage.Appender.
ID storage.SeriesRef
Name string
lastSeen time.Time
metadata metadata.Metadata
// Used for determining when a write needs to occur.
lastWrite, lastUpdate time.Time
}
// WriteTo writes the metadata to app if the metadata has changed since the
// last update, otherwise WriteTo is a no-op.
func (md *memoryMetadata) WriteTo(app storage.Appender, ts time.Time) error {
md.Lock()
defer md.Unlock()
if !md.lastWrite.Before(md.lastUpdate) {
return nil
}
labels := labels.FromStrings(model.MetricNameLabel, md.Name)
ref, err := app.UpdateMetadata(md.ID, labels, md.metadata)
if err != nil {
return err
}
if ref != md.ID {
md.ID = ref
}
md.lastWrite = md.lastUpdate
return nil
}
// Update updates the metadata used by md. The next call to WriteTo will write
// the new metadata only if m is different from the last metadata stored.
func (md *memoryMetadata) Update(m metadata.Metadata) {
md.Lock()
defer md.Unlock()
md.lastSeen = time.Now()
// Metadata hasn't changed; don't do anything.
if m == md.metadata {
return
}
md.metadata = m
md.lastUpdate = time.Now()
}