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-rw-r--r--vendor/github.com/prometheus/common/model/value_float.go100
1 files changed, 100 insertions, 0 deletions
diff --git a/vendor/github.com/prometheus/common/model/value_float.go b/vendor/github.com/prometheus/common/model/value_float.go
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+++ b/vendor/github.com/prometheus/common/model/value_float.go
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+// Copyright 2013 The Prometheus Authors
+// 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 model
+
+import (
+ "encoding/json"
+ "fmt"
+ "math"
+ "strconv"
+)
+
+var (
+ // ZeroSamplePair is the pseudo zero-value of SamplePair used to signal a
+ // non-existing sample pair. It is a SamplePair with timestamp Earliest and
+ // value 0.0. Note that the natural zero value of SamplePair has a timestamp
+ // of 0, which is possible to appear in a real SamplePair and thus not
+ // suitable to signal a non-existing SamplePair.
+ ZeroSamplePair = SamplePair{Timestamp: Earliest}
+)
+
+// A SampleValue is a representation of a value for a given sample at a given
+// time.
+type SampleValue float64
+
+// MarshalJSON implements json.Marshaler.
+func (v SampleValue) MarshalJSON() ([]byte, error) {
+ return json.Marshal(v.String())
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (v *SampleValue) UnmarshalJSON(b []byte) error {
+ if len(b) < 2 || b[0] != '"' || b[len(b)-1] != '"' {
+ return fmt.Errorf("sample value must be a quoted string")
+ }
+ f, err := strconv.ParseFloat(string(b[1:len(b)-1]), 64)
+ if err != nil {
+ return err
+ }
+ *v = SampleValue(f)
+ return nil
+}
+
+// Equal returns true if the value of v and o is equal or if both are NaN. Note
+// that v==o is false if both are NaN. If you want the conventional float
+// behavior, use == to compare two SampleValues.
+func (v SampleValue) Equal(o SampleValue) bool {
+ if v == o {
+ return true
+ }
+ return math.IsNaN(float64(v)) && math.IsNaN(float64(o))
+}
+
+func (v SampleValue) String() string {
+ return strconv.FormatFloat(float64(v), 'f', -1, 64)
+}
+
+// SamplePair pairs a SampleValue with a Timestamp.
+type SamplePair struct {
+ Timestamp Time
+ Value SampleValue
+}
+
+func (s SamplePair) MarshalJSON() ([]byte, error) {
+ t, err := json.Marshal(s.Timestamp)
+ if err != nil {
+ return nil, err
+ }
+ v, err := json.Marshal(s.Value)
+ if err != nil {
+ return nil, err
+ }
+ return []byte(fmt.Sprintf("[%s,%s]", t, v)), nil
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (s *SamplePair) UnmarshalJSON(b []byte) error {
+ v := [...]json.Unmarshaler{&s.Timestamp, &s.Value}
+ return json.Unmarshal(b, &v)
+}
+
+// Equal returns true if this SamplePair and o have equal Values and equal
+// Timestamps. The semantics of Value equality is defined by SampleValue.Equal.
+func (s *SamplePair) Equal(o *SamplePair) bool {
+ return s == o || (s.Value.Equal(o.Value) && s.Timestamp.Equal(o.Timestamp))
+}
+
+func (s SamplePair) String() string {
+ return fmt.Sprintf("%s @[%s]", s.Value, s.Timestamp)
+}