Vendor common/model package

Godeps/Godeps.json

@@ -58,6 +58,10 @@
 			"ImportPath": "github.com/prometheus/client_golang/text",
 			"Rev": "3a499bf7fc46bc58337ce612d0cbb29c550b8118"
 		},
+		{
+			"ImportPath": "github.com/prometheus/common/model",
+			"Rev": "2502df85be1b9482ed669faa6b7cfe7f850eb08e"
+		},
 		{
 			"ImportPath": "github.com/prometheus/client_model/go",
 			"Comment": "model-0.0.2-12-gfa8ad6f",

Godeps/_workspace/src/github.com/prometheus/common/model/fingerprinting.go

@@ -0,0 +1,105 @@
+// 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 (
+	"fmt"
+	"strconv"
+)
+
+// Fingerprint provides a hash-capable representation of a Metric.
+// For our purposes, FNV-1A 64-bit is used.
+type Fingerprint uint64
+
+// FingerprintFromString transforms a string representation into a Fingerprint.
+func FingerprintFromString(s string) (Fingerprint, error) {
+	num, err := strconv.ParseUint(s, 16, 64)
+	return Fingerprint(num), err
+}
+
+// ParseFingerprint parses the input string into a fingerprint.
+func ParseFingerprint(s string) (Fingerprint, error) {
+	num, err := strconv.ParseUint(s, 16, 64)
+	if err != nil {
+		return 0, err
+	}
+	return Fingerprint(num), nil
+}
+
+func (f Fingerprint) String() string {
+	return fmt.Sprintf("%016x", uint64(f))
+}
+
+// Fingerprints represents a collection of Fingerprint subject to a given
+// natural sorting scheme. It implements sort.Interface.
+type Fingerprints []Fingerprint
+
+// Len implements sort.Interface.
+func (f Fingerprints) Len() int {
+	return len(f)
+}
+
+// Less implements sort.Interface.
+func (f Fingerprints) Less(i, j int) bool {
+	return f[i] < f[j]
+}
+
+// Swap implements sort.Interface.
+func (f Fingerprints) Swap(i, j int) {
+	f[i], f[j] = f[j], f[i]
+}
+
+// FingerprintSet is a set of Fingerprints.
+type FingerprintSet map[Fingerprint]struct{}
+
+// Equal returns true if both sets contain the same elements (and not more).
+func (s FingerprintSet) Equal(o FingerprintSet) bool {
+	if len(s) != len(o) {
+		return false
+	}
+
+	for k := range s {
+		if _, ok := o[k]; !ok {
+			return false
+		}
+	}
+
+	return true
+}
+
+// Intersection returns the elements contained in both sets.
+func (s FingerprintSet) Intersection(o FingerprintSet) FingerprintSet {
+	myLength, otherLength := len(s), len(o)
+	if myLength == 0 || otherLength == 0 {
+		return FingerprintSet{}
+	}
+
+	subSet := s
+	superSet := o
+
+	if otherLength < myLength {
+		subSet = o
+		superSet = s
+	}
+
+	out := FingerprintSet{}
+
+	for k := range subSet {
+		if _, ok := superSet[k]; ok {
+			out[k] = struct{}{}
+		}
+	}
+
+	return out
+}

Godeps/_workspace/src/github.com/prometheus/common/model/labels.go

@@ -0,0 +1,185 @@
+// 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"
+	"regexp"
+	"sort"
+	"strings"
+)
+
+const (
+	// ExportedLabelPrefix is the prefix to prepend to the label names present in
+	// exported metrics if a label of the same name is added by the server.
+	ExportedLabelPrefix LabelName = "exported_"
+
+	// MetricNameLabel is the label name indicating the metric name of a
+	// timeseries.
+	MetricNameLabel LabelName = "__name__"
+
+	// SchemeLabel is the name of the label that holds the scheme on which to
+	// scrape a target.
+	SchemeLabel LabelName = "__scheme__"
+
+	// AddressLabel is the name of the label that holds the address of
+	// a scrape target.
+	AddressLabel LabelName = "__address__"
+
+	// MetricsPathLabel is the name of the label that holds the path on which to
+	// scrape a target.
+	MetricsPathLabel LabelName = "__metrics_path__"
+
+	// ReservedLabelPrefix is a prefix which is not legal in user-supplied
+	// label names.
+	ReservedLabelPrefix = "__"
+
+	// MetaLabelPrefix is a prefix for labels that provide meta information.
+	// Labels with this prefix are used for intermediate label processing and
+	// will not be attached to time series.
+	MetaLabelPrefix = "__meta_"
+
+	// TmpLabelPrefix is a prefix for temporary labels as part of relabelling.
+	// Labels with this prefix are used for intermediate label processing and
+	// will not be attached to time series. This is reserved for use in
+	// Prometheus configuration files by users.
+	TmpLabelPrefix = "__tmp_"
+
+	// ParamLabelPrefix is a prefix for labels that provide URL parameters
+	// used to scrape a target.
+	ParamLabelPrefix = "__param_"
+
+	// JobLabel is the label name indicating the job from which a timeseries
+	// was scraped.
+	JobLabel LabelName = "job"
+
+	// InstanceLabel is the label name used for the instance label.
+	InstanceLabel LabelName = "instance"
+
+	// BucketLabel is used for the label that defines the upper bound of a
+	// bucket of a histogram ("le" -> "less or equal").
+	BucketLabel = "le"
+
+	// QuantileLabel is used for the label that defines the quantile in a
+	// summary.
+	QuantileLabel = "quantile"
+)
+
+// LabelNameRE is a regular expression matching valid label names.
+var LabelNameRE = regexp.MustCompile("^[a-zA-Z_][a-zA-Z0-9_]*$")
+
+// A LabelName is a key for a LabelSet or Metric.  It has a value associated
+// therewith.
+type LabelName string
+
+// UnmarshalYAML implements the yaml.Unmarshaler interface.
+func (ln *LabelName) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var s string
+	if err := unmarshal(&s); err != nil {
+		return err
+	}
+	if !LabelNameRE.MatchString(s) {
+		return fmt.Errorf("%q is not a valid label name", s)
+	}
+	*ln = LabelName(s)
+	return nil
+}
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (ln *LabelName) UnmarshalJSON(b []byte) error {
+	var s string
+	if err := json.Unmarshal(b, &s); err != nil {
+		return err
+	}
+	if !LabelNameRE.MatchString(s) {
+		return fmt.Errorf("%q is not a valid label name", s)
+	}
+	*ln = LabelName(s)
+	return nil
+}
+
+// LabelNames is a sortable LabelName slice. In implements sort.Interface.
+type LabelNames []LabelName
+
+func (l LabelNames) Len() int {
+	return len(l)
+}
+
+func (l LabelNames) Less(i, j int) bool {
+	return l[i] < l[j]
+}
+
+func (l LabelNames) Swap(i, j int) {
+	l[i], l[j] = l[j], l[i]
+}
+
+func (l LabelNames) String() string {
+	labelStrings := make([]string, 0, len(l))
+	for _, label := range l {
+		labelStrings = append(labelStrings, string(label))
+	}
+	return strings.Join(labelStrings, ", ")
+}
+
+// A LabelValue is an associated value for a LabelName.
+type LabelValue string
+
+// LabelValues is a sortable LabelValue slice. It implements sort.Interface.
+type LabelValues []LabelValue
+
+func (l LabelValues) Len() int {
+	return len(l)
+}
+
+func (l LabelValues) Less(i, j int) bool {
+	return sort.StringsAreSorted([]string{string(l[i]), string(l[j])})
+}
+
+func (l LabelValues) Swap(i, j int) {
+	l[i], l[j] = l[j], l[i]
+}
+
+// LabelPair pairs a name with a value.
+type LabelPair struct {
+	Name  LabelName
+	Value LabelValue
+}
+
+// LabelPairs is a sortable slice of LabelPair pointers. It implements
+// sort.Interface.
+type LabelPairs []*LabelPair
+
+func (l LabelPairs) Len() int {
+	return len(l)
+}
+
+func (l LabelPairs) Less(i, j int) bool {
+	switch {
+	case l[i].Name > l[j].Name:
+		return false
+	case l[i].Name < l[j].Name:
+		return true
+	case l[i].Value > l[j].Value:
+		return false
+	case l[i].Value < l[j].Value:
+		return true
+	default:
+		return false
+	}
+}
+
+func (l LabelPairs) Swap(i, j int) {
+	l[i], l[j] = l[j], l[i]
+}

Godeps/_workspace/src/github.com/prometheus/common/model/labels_test.go

@@ -0,0 +1,91 @@
+// 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 (
+	"sort"
+	"testing"
+)
+
+func testLabelNames(t testing.TB) {
+	var scenarios = []struct {
+		in  LabelNames
+		out LabelNames
+	}{
+		{
+			in:  LabelNames{"ZZZ", "zzz"},
+			out: LabelNames{"ZZZ", "zzz"},
+		},
+		{
+			in:  LabelNames{"aaa", "AAA"},
+			out: LabelNames{"AAA", "aaa"},
+		},
+	}
+
+	for i, scenario := range scenarios {
+		sort.Sort(scenario.in)
+
+		for j, expected := range scenario.out {
+			if expected != scenario.in[j] {
+				t.Errorf("%d.%d expected %s, got %s", i, j, expected, scenario.in[j])
+			}
+		}
+	}
+}
+
+func TestLabelNames(t *testing.T) {
+	testLabelNames(t)
+}
+
+func BenchmarkLabelNames(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		testLabelNames(b)
+	}
+}
+
+func testLabelValues(t testing.TB) {
+	var scenarios = []struct {
+		in  LabelValues
+		out LabelValues
+	}{
+		{
+			in:  LabelValues{"ZZZ", "zzz"},
+			out: LabelValues{"ZZZ", "zzz"},
+		},
+		{
+			in:  LabelValues{"aaa", "AAA"},
+			out: LabelValues{"AAA", "aaa"},
+		},
+	}
+
+	for i, scenario := range scenarios {
+		sort.Sort(scenario.in)
+
+		for j, expected := range scenario.out {
+			if expected != scenario.in[j] {
+				t.Errorf("%d.%d expected %s, got %s", i, j, expected, scenario.in[j])
+			}
+		}
+	}
+}
+
+func TestLabelValues(t *testing.T) {
+	testLabelValues(t)
+}
+
+func BenchmarkLabelValues(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		testLabelValues(b)
+	}
+}

Godeps/_workspace/src/github.com/prometheus/common/model/labelset.go

@@ -0,0 +1,153 @@
+// 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"
+	"sort"
+	"strings"
+)
+
+// A LabelSet is a collection of LabelName and LabelValue pairs.  The LabelSet
+// may be fully-qualified down to the point where it may resolve to a single
+// Metric in the data store or not.  All operations that occur within the realm
+// of a LabelSet can emit a vector of Metric entities to which the LabelSet may
+// match.
+type LabelSet map[LabelName]LabelValue
+
+func (ls LabelSet) Equal(o LabelSet) bool {
+	if len(ls) != len(o) {
+		return false
+	}
+	for ln, lv := range ls {
+		olv, ok := o[ln]
+		if !ok {
+			return false
+		}
+		if olv != lv {
+			return false
+		}
+	}
+	return true
+}
+
+// Before compares the metrics, using the following criteria:
+//
+// If m has fewer labels than o, it is before o. If it has more, it is not.
+//
+// If the number of labels is the same, the superset of all label names is
+// sorted alphanumerically. The first differing label pair found in that order
+// determines the outcome: If the label does not exist at all in m, then m is
+// before o, and vice versa. Otherwise the label value is compared
+// alphanumerically.
+//
+// If m and o are equal, the method returns false.
+func (ls LabelSet) Before(o LabelSet) bool {
+	if len(ls) < len(o) {
+		return true
+	}
+	if len(ls) > len(o) {
+		return false
+	}
+
+	lns := make(LabelNames, 0, len(ls)+len(o))
+	for ln := range ls {
+		lns = append(lns, ln)
+	}
+	for ln := range o {
+		lns = append(lns, ln)
+	}
+	// It's probably not worth it to de-dup lns.
+	sort.Sort(lns)
+	for _, ln := range lns {
+		mlv, ok := ls[ln]
+		if !ok {
+			return true
+		}
+		olv, ok := o[ln]
+		if !ok {
+			return false
+		}
+		if mlv < olv {
+			return true
+		}
+		if mlv > olv {
+			return false
+		}
+	}
+	return false
+}
+
+func (ls LabelSet) Clone() LabelSet {
+	lsn := make(LabelSet, len(ls))
+	for ln, lv := range ls {
+		lsn[ln] = lv
+	}
+	return lsn
+}
+
+// Merge is a helper function to non-destructively merge two label sets.
+func (l LabelSet) Merge(other LabelSet) LabelSet {
+	result := make(LabelSet, len(l))
+
+	for k, v := range l {
+		result[k] = v
+	}
+
+	for k, v := range other {
+		result[k] = v
+	}
+
+	return result
+}
+
+func (l LabelSet) String() string {
+	lstrs := make([]string, 0, len(l))
+	for l, v := range l {
+		lstrs = append(lstrs, fmt.Sprintf("%s=%q", l, v))
+	}
+
+	sort.Strings(lstrs)
+	return fmt.Sprintf("{%s}", strings.Join(lstrs, ", "))
+}
+
+// Fingerprint returns the LabelSet's fingerprint.
+func (ls LabelSet) Fingerprint() Fingerprint {
+	return labelSetToFingerprint(ls)
+}
+
+// FastFingerprint returns the LabelSet's Fingerprint calculated by a faster hashing
+// algorithm, which is, however, more susceptible to hash collisions.
+func (ls LabelSet) FastFingerprint() Fingerprint {
+	return labelSetToFastFingerprint(ls)
+}
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (l *LabelSet) UnmarshalJSON(b []byte) error {
+	var m map[LabelName]LabelValue
+	if err := json.Unmarshal(b, &m); err != nil {
+		return err
+	}
+	// encoding/json only unmarshals maps of the form map[string]T. It treats
+	// LabelName as a string and does not call its UnmarshalJSON method.
+	// Thus, we have to replicate the behavior here.
+	for ln := range m {
+		if !LabelNameRE.MatchString(string(ln)) {
+			return fmt.Errorf("%q is not a valid label name", ln)
+		}
+	}
+	*l = LabelSet(m)
+	return nil
+}

Godeps/_workspace/src/github.com/prometheus/common/model/metric.go

@@ -0,0 +1,120 @@
+// 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"
+	"sort"
+	"strings"
+)
+
+var separator = []byte{0}
+
+// A Metric is similar to a LabelSet, but the key difference is that a Metric is
+// a singleton and refers to one and only one stream of samples.
+type Metric LabelSet
+
+// Equal compares the metrics.
+func (m Metric) Equal(o Metric) bool {
+	return LabelSet(m).Equal(LabelSet(o))
+}
+
+// Before compares the metrics' underlying label sets.
+func (m Metric) Before(o Metric) bool {
+	return LabelSet(m).Before(LabelSet(o))
+}
+
+// Clone returns a copy of the Metric.
+func (m Metric) Clone() Metric {
+	clone := Metric{}
+	for k, v := range m {
+		clone[k] = v
+	}
+	return clone
+}
+
+func (m Metric) String() string {
+	metricName, hasName := m[MetricNameLabel]
+	numLabels := len(m) - 1
+	if !hasName {
+		numLabels = len(m)
+	}
+	labelStrings := make([]string, 0, numLabels)
+	for label, value := range m {
+		if label != MetricNameLabel {
+			labelStrings = append(labelStrings, fmt.Sprintf("%s=%q", label, value))
+		}
+	}
+
+	switch numLabels {
+	case 0:
+		if hasName {
+			return string(metricName)
+		}
+		return "{}"
+	default:
+		sort.Strings(labelStrings)
+		return fmt.Sprintf("%s{%s}", metricName, strings.Join(labelStrings, ", "))
+	}
+}
+
+// Fingerprint returns a Metric's Fingerprint.
+func (m Metric) Fingerprint() Fingerprint {
+	return LabelSet(m).Fingerprint()
+}
+
+// FastFingerprint returns a Metric's Fingerprint calculated by a faster hashing
+// algorithm, which is, however, more susceptible to hash collisions.
+func (m Metric) FastFingerprint() Fingerprint {
+	return LabelSet(m).FastFingerprint()
+}
+
+// COWMetric wraps a Metric to enable copy-on-write access patterns.
+type COWMetric struct {
+	Copied bool
+	Metric Metric
+}
+
+// Set sets a label name in the wrapped Metric to a given value and copies the
+// Metric initially, if it is not already a copy.
+func (m *COWMetric) Set(ln LabelName, lv LabelValue) {
+	m.doCOW()
+	m.Metric[ln] = lv
+}
+
+// Delete deletes a given label name from the wrapped Metric and copies the
+// Metric initially, if it is not already a copy.
+func (m *COWMetric) Del(ln LabelName) {
+	m.doCOW()
+	delete(m.Metric, ln)
+}
+
+// doCOW copies the underlying Metric if it is not already a copy.
+func (m *COWMetric) doCOW() {
+	if !m.Copied {
+		m.Metric = m.Metric.Clone()
+		m.Copied = true
+	}
+}
+
+// String implements fmt.Stringer.
+func (m COWMetric) String() string {
+	return m.Metric.String()
+}
+
+// MarshalJSON implements json.Marshaler.
+func (m COWMetric) MarshalJSON() ([]byte, error) {
+	return json.Marshal(m.Metric)
+}

Godeps/_workspace/src/github.com/prometheus/common/model/metric_test.go

@@ -0,0 +1,132 @@
+// 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 "testing"
+
+func testMetric(t testing.TB) {
+	var scenarios = []struct {
+		input           LabelSet
+		fingerprint     Fingerprint
+		fastFingerprint Fingerprint
+	}{
+		{
+			input:           LabelSet{},
+			fingerprint:     14695981039346656037,
+			fastFingerprint: 14695981039346656037,
+		},
+		{
+			input: LabelSet{
+				"first_name":   "electro",
+				"occupation":   "robot",
+				"manufacturer": "westinghouse",
+			},
+			fingerprint:     5911716720268894962,
+			fastFingerprint: 11310079640881077873,
+		},
+		{
+			input: LabelSet{
+				"x": "y",
+			},
+			fingerprint:     8241431561484471700,
+			fastFingerprint: 13948396922932177635,
+		},
+		{
+			input: LabelSet{
+				"a": "bb",
+				"b": "c",
+			},
+			fingerprint:     3016285359649981711,
+			fastFingerprint: 3198632812309449502,
+		},
+		{
+			input: LabelSet{
+				"a":  "b",
+				"bb": "c",
+			},
+			fingerprint:     7122421792099404749,
+			fastFingerprint: 5774953389407657638,
+		},
+	}
+
+	for i, scenario := range scenarios {
+		input := Metric(scenario.input)
+
+		if scenario.fingerprint != input.Fingerprint() {
+			t.Errorf("%d. expected %d, got %d", i, scenario.fingerprint, input.Fingerprint())
+		}
+		if scenario.fastFingerprint != input.FastFingerprint() {
+			t.Errorf("%d. expected %d, got %d", i, scenario.fastFingerprint, input.FastFingerprint())
+		}
+	}
+}
+
+func TestMetric(t *testing.T) {
+	testMetric(t)
+}
+
+func BenchmarkMetric(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		testMetric(b)
+	}
+}
+
+func TestCOWMetric(t *testing.T) {
+	testMetric := Metric{
+		"to_delete": "test1",
+		"to_change": "test2",
+	}
+
+	scenarios := []struct {
+		fn  func(*COWMetric)
+		out Metric
+	}{
+		{
+			fn: func(cm *COWMetric) {
+				cm.Del("to_delete")
+			},
+			out: Metric{
+				"to_change": "test2",
+			},
+		},
+		{
+			fn: func(cm *COWMetric) {
+				cm.Set("to_change", "changed")
+			},
+			out: Metric{
+				"to_delete": "test1",
+				"to_change": "changed",
+			},
+		},
+	}
+
+	for i, s := range scenarios {
+		orig := testMetric.Clone()
+		cm := &COWMetric{
+			Metric: orig,
+		}
+
+		s.fn(cm)
+
+		// Test that the original metric was not modified.
+		if !orig.Equal(testMetric) {
+			t.Fatalf("%d. original metric changed; expected %v, got %v", i, testMetric, orig)
+		}
+
+		// Test that the new metric has the right changes.
+		if !cm.Metric.Equal(s.out) {
+			t.Fatalf("%d. copied metric doesn't contain expected changes; expected %v, got %v", i, s.out, cm.Metric)
+		}
+	}
+}

Godeps/_workspace/src/github.com/prometheus/common/model/model.go

@@ -0,0 +1,16 @@
+// 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 contains common data structures that are shared across
+// Prometheus componenets and libraries.
+package model

Godeps/_workspace/src/github.com/prometheus/common/model/signature.go

@@ -0,0 +1,190 @@
+// Copyright 2014 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 (
+	"bytes"
+	"hash"
+	"hash/fnv"
+	"sort"
+	"sync"
+)
+
+// SeparatorByte is a byte that cannot occur in valid UTF-8 sequences and is
+// used to separate label names, label values, and other strings from each other
+// when calculating their combined hash value (aka signature aka fingerprint).
+const SeparatorByte byte = 255
+
+var (
+	// cache the signature of an empty label set.
+	emptyLabelSignature = fnv.New64a().Sum64()
+
+	hashAndBufPool sync.Pool
+)
+
+type hashAndBuf struct {
+	h hash.Hash64
+	b bytes.Buffer
+}
+
+func getHashAndBuf() *hashAndBuf {
+	hb := hashAndBufPool.Get()
+	if hb == nil {
+		return &hashAndBuf{h: fnv.New64a()}
+	}
+	return hb.(*hashAndBuf)
+}
+
+func putHashAndBuf(hb *hashAndBuf) {
+	hb.h.Reset()
+	hb.b.Reset()
+	hashAndBufPool.Put(hb)
+}
+
+// LabelsToSignature returns a quasi-unique signature (i.e., fingerprint) for a
+// given label set. (Collisions are possible but unlikely if the number of label
+// sets the function is applied to is small.)
+func LabelsToSignature(labels map[string]string) uint64 {
+	if len(labels) == 0 {
+		return emptyLabelSignature
+	}
+
+	labelNames := make([]string, 0, len(labels))
+	for labelName := range labels {
+		labelNames = append(labelNames, labelName)
+	}
+	sort.Strings(labelNames)
+
+	hb := getHashAndBuf()
+	defer putHashAndBuf(hb)
+
+	for _, labelName := range labelNames {
+		hb.b.WriteString(labelName)
+		hb.b.WriteByte(SeparatorByte)
+		hb.b.WriteString(labels[labelName])
+		hb.b.WriteByte(SeparatorByte)
+		hb.h.Write(hb.b.Bytes())
+		hb.b.Reset()
+	}
+	return hb.h.Sum64()
+}
+
+// labelSetToFingerprint works exactly as LabelsToSignature but takes a LabelSet as
+// parameter (rather than a label map) and returns a Fingerprint.
+func labelSetToFingerprint(ls LabelSet) Fingerprint {
+	if len(ls) == 0 {
+		return Fingerprint(emptyLabelSignature)
+	}
+
+	labelNames := make(LabelNames, 0, len(ls))
+	for labelName := range ls {
+		labelNames = append(labelNames, labelName)
+	}
+	sort.Sort(labelNames)
+
+	hb := getHashAndBuf()
+	defer putHashAndBuf(hb)
+
+	for _, labelName := range labelNames {
+		hb.b.WriteString(string(labelName))
+		hb.b.WriteByte(SeparatorByte)
+		hb.b.WriteString(string(ls[labelName]))
+		hb.b.WriteByte(SeparatorByte)
+		hb.h.Write(hb.b.Bytes())
+		hb.b.Reset()
+	}
+	return Fingerprint(hb.h.Sum64())
+}
+
+// labelSetToFastFingerprint works similar to labelSetToFingerprint but uses a
+// faster and less allocation-heavy hash function, which is more susceptible to
+// create hash collisions. Therefore, collision detection should be applied.
+func labelSetToFastFingerprint(ls LabelSet) Fingerprint {
+	if len(ls) == 0 {
+		return Fingerprint(emptyLabelSignature)
+	}
+
+	var result uint64
+	hb := getHashAndBuf()
+	defer putHashAndBuf(hb)
+
+	for labelName, labelValue := range ls {
+		hb.b.WriteString(string(labelName))
+		hb.b.WriteByte(SeparatorByte)
+		hb.b.WriteString(string(labelValue))
+		hb.h.Write(hb.b.Bytes())
+		result ^= hb.h.Sum64()
+		hb.h.Reset()
+		hb.b.Reset()
+	}
+	return Fingerprint(result)
+}
+
+// SignatureForLabels works like LabelsToSignature but takes a Metric as
+// parameter (rather than a label map) and only includes the labels with the
+// specified LabelNames into the signature calculation. The labels passed in
+// will be sorted by this function.
+func SignatureForLabels(m Metric, labels ...LabelName) uint64 {
+	if len(m) == 0 || len(labels) == 0 {
+		return emptyLabelSignature
+	}
+
+	sort.Sort(LabelNames(labels))
+
+	hb := getHashAndBuf()
+	defer putHashAndBuf(hb)
+
+	for _, label := range labels {
+		hb.b.WriteString(string(label))
+		hb.b.WriteByte(SeparatorByte)
+		hb.b.WriteString(string(m[label]))
+		hb.b.WriteByte(SeparatorByte)
+		hb.h.Write(hb.b.Bytes())
+		hb.b.Reset()
+	}
+	return hb.h.Sum64()
+}
+
+// SignatureWithoutLabels works like LabelsToSignature but takes a Metric as
+// parameter (rather than a label map) and excludes the labels with any of the
+// specified LabelNames from the signature calculation.
+func SignatureWithoutLabels(m Metric, labels map[LabelName]struct{}) uint64 {
+	if len(m) == 0 {
+		return emptyLabelSignature
+	}
+
+	labelNames := make(LabelNames, 0, len(m))
+	for labelName := range m {
+		if _, exclude := labels[labelName]; !exclude {
+			labelNames = append(labelNames, labelName)
+		}
+	}
+	if len(labelNames) == 0 {
+		return emptyLabelSignature
+	}
+	sort.Sort(labelNames)
+
+	hb := getHashAndBuf()
+	defer putHashAndBuf(hb)
+
+	for _, labelName := range labelNames {
+		hb.b.WriteString(string(labelName))
+		hb.b.WriteByte(SeparatorByte)
+		hb.b.WriteString(string(m[labelName]))
+		hb.b.WriteByte(SeparatorByte)
+		hb.h.Write(hb.b.Bytes())
+		hb.b.Reset()
+	}
+	return hb.h.Sum64()
+}

Godeps/_workspace/src/github.com/prometheus/common/model/signature_test.go

@@ -0,0 +1,304 @@
+// Copyright 2014 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 (
+	"runtime"
+	"sync"
+	"testing"
+)
+
+func TestLabelsToSignature(t *testing.T) {
+	var scenarios = []struct {
+		in  map[string]string
+		out uint64
+	}{
+		{
+			in:  map[string]string{},
+			out: 14695981039346656037,
+		},
+		{
+			in:  map[string]string{"name": "garland, briggs", "fear": "love is not enough"},
+			out: 5799056148416392346,
+		},
+	}
+
+	for i, scenario := range scenarios {
+		actual := LabelsToSignature(scenario.in)
+
+		if actual != scenario.out {
+			t.Errorf("%d. expected %d, got %d", i, scenario.out, actual)
+		}
+	}
+}
+
+func TestMetricToFingerprint(t *testing.T) {
+	var scenarios = []struct {
+		in  LabelSet
+		out Fingerprint
+	}{
+		{
+			in:  LabelSet{},
+			out: 14695981039346656037,
+		},
+		{
+			in:  LabelSet{"name": "garland, briggs", "fear": "love is not enough"},
+			out: 5799056148416392346,
+		},
+	}
+
+	for i, scenario := range scenarios {
+		actual := labelSetToFingerprint(scenario.in)
+
+		if actual != scenario.out {
+			t.Errorf("%d. expected %d, got %d", i, scenario.out, actual)
+		}
+	}
+}
+
+func TestMetricToFastFingerprint(t *testing.T) {
+	var scenarios = []struct {
+		in  LabelSet
+		out Fingerprint
+	}{
+		{
+			in:  LabelSet{},
+			out: 14695981039346656037,
+		},
+		{
+			in:  LabelSet{"name": "garland, briggs", "fear": "love is not enough"},
+			out: 12952432476264840823,
+		},
+	}
+
+	for i, scenario := range scenarios {
+		actual := labelSetToFastFingerprint(scenario.in)
+
+		if actual != scenario.out {
+			t.Errorf("%d. expected %d, got %d", i, scenario.out, actual)
+		}
+	}
+}
+
+func TestSignatureForLabels(t *testing.T) {
+	var scenarios = []struct {
+		in     Metric
+		labels LabelNames
+		out    uint64
+	}{
+		{
+			in:     Metric{},
+			labels: nil,
+			out:    14695981039346656037,
+		},
+		{
+			in:     Metric{"name": "garland, briggs", "fear": "love is not enough"},
+			labels: LabelNames{"fear", "name"},
+			out:    5799056148416392346,
+		},
+		{
+			in:     Metric{"name": "garland, briggs", "fear": "love is not enough", "foo": "bar"},
+			labels: LabelNames{"fear", "name"},
+			out:    5799056148416392346,
+		},
+		{
+			in:     Metric{"name": "garland, briggs", "fear": "love is not enough"},
+			labels: LabelNames{},
+			out:    14695981039346656037,
+		},
+		{
+			in:     Metric{"name": "garland, briggs", "fear": "love is not enough"},
+			labels: nil,
+			out:    14695981039346656037,
+		},
+	}
+
+	for i, scenario := range scenarios {
+		actual := SignatureForLabels(scenario.in, scenario.labels...)
+
+		if actual != scenario.out {
+			t.Errorf("%d. expected %d, got %d", i, scenario.out, actual)
+		}
+	}
+}
+
+func TestSignatureWithoutLabels(t *testing.T) {
+	var scenarios = []struct {
+		in     Metric
+		labels map[LabelName]struct{}
+		out    uint64
+	}{
+		{
+			in:     Metric{},
+			labels: nil,
+			out:    14695981039346656037,
+		},
+		{
+			in:     Metric{"name": "garland, briggs", "fear": "love is not enough"},
+			labels: map[LabelName]struct{}{"fear": struct{}{}, "name": struct{}{}},
+			out:    14695981039346656037,
+		},
+		{
+			in:     Metric{"name": "garland, briggs", "fear": "love is not enough", "foo": "bar"},
+			labels: map[LabelName]struct{}{"foo": struct{}{}},
+			out:    5799056148416392346,
+		},
+		{
+			in:     Metric{"name": "garland, briggs", "fear": "love is not enough"},
+			labels: map[LabelName]struct{}{},
+			out:    5799056148416392346,
+		},
+		{
+			in:     Metric{"name": "garland, briggs", "fear": "love is not enough"},
+			labels: nil,
+			out:    5799056148416392346,
+		},
+	}
+
+	for i, scenario := range scenarios {
+		actual := SignatureWithoutLabels(scenario.in, scenario.labels)
+
+		if actual != scenario.out {
+			t.Errorf("%d. expected %d, got %d", i, scenario.out, actual)
+		}
+	}
+}
+
+func benchmarkLabelToSignature(b *testing.B, l map[string]string, e uint64) {
+	for i := 0; i < b.N; i++ {
+		if a := LabelsToSignature(l); a != e {
+			b.Fatalf("expected signature of %d for %s, got %d", e, l, a)
+		}
+	}
+}
+
+func BenchmarkLabelToSignatureScalar(b *testing.B) {
+	benchmarkLabelToSignature(b, nil, 14695981039346656037)
+}
+
+func BenchmarkLabelToSignatureSingle(b *testing.B) {
+	benchmarkLabelToSignature(b, map[string]string{"first-label": "first-label-value"}, 5146282821936882169)
+}
+
+func BenchmarkLabelToSignatureDouble(b *testing.B) {
+	benchmarkLabelToSignature(b, map[string]string{"first-label": "first-label-value", "second-label": "second-label-value"}, 3195800080984914717)
+}
+
+func BenchmarkLabelToSignatureTriple(b *testing.B) {
+	benchmarkLabelToSignature(b, map[string]string{"first-label": "first-label-value", "second-label": "second-label-value", "third-label": "third-label-value"}, 13843036195897128121)
+}
+
+func benchmarkMetricToFingerprint(b *testing.B, ls LabelSet, e Fingerprint) {
+	for i := 0; i < b.N; i++ {
+		if a := labelSetToFingerprint(ls); a != e {
+			b.Fatalf("expected signature of %d for %s, got %d", e, ls, a)
+		}
+	}
+}
+
+func BenchmarkMetricToFingerprintScalar(b *testing.B) {
+	benchmarkMetricToFingerprint(b, nil, 14695981039346656037)
+}
+
+func BenchmarkMetricToFingerprintSingle(b *testing.B) {
+	benchmarkMetricToFingerprint(b, LabelSet{"first-label": "first-label-value"}, 5146282821936882169)
+}
+
+func BenchmarkMetricToFingerprintDouble(b *testing.B) {
+	benchmarkMetricToFingerprint(b, LabelSet{"first-label": "first-label-value", "second-label": "second-label-value"}, 3195800080984914717)
+}
+
+func BenchmarkMetricToFingerprintTriple(b *testing.B) {
+	benchmarkMetricToFingerprint(b, LabelSet{"first-label": "first-label-value", "second-label": "second-label-value", "third-label": "third-label-value"}, 13843036195897128121)
+}
+
+func benchmarkMetricToFastFingerprint(b *testing.B, ls LabelSet, e Fingerprint) {
+	for i := 0; i < b.N; i++ {
+		if a := labelSetToFastFingerprint(ls); a != e {
+			b.Fatalf("expected signature of %d for %s, got %d", e, ls, a)
+		}
+	}
+}
+
+func BenchmarkMetricToFastFingerprintScalar(b *testing.B) {
+	benchmarkMetricToFastFingerprint(b, nil, 14695981039346656037)
+}
+
+func BenchmarkMetricToFastFingerprintSingle(b *testing.B) {
+	benchmarkMetricToFastFingerprint(b, LabelSet{"first-label": "first-label-value"}, 5147259542624943964)
+}
+
+func BenchmarkMetricToFastFingerprintDouble(b *testing.B) {
+	benchmarkMetricToFastFingerprint(b, LabelSet{"first-label": "first-label-value", "second-label": "second-label-value"}, 18269973311206963528)
+}
+
+func BenchmarkMetricToFastFingerprintTriple(b *testing.B) {
+	benchmarkMetricToFastFingerprint(b, LabelSet{"first-label": "first-label-value", "second-label": "second-label-value", "third-label": "third-label-value"}, 15738406913934009676)
+}
+
+func TestEmptyLabelSignature(t *testing.T) {
+	input := []map[string]string{nil, {}}
+
+	var ms runtime.MemStats
+	runtime.ReadMemStats(&ms)
+
+	alloc := ms.Alloc
+
+	for _, labels := range input {
+		LabelsToSignature(labels)
+	}
+
+	runtime.ReadMemStats(&ms)
+
+	if got := ms.Alloc; alloc != got {
+		t.Fatal("expected LabelsToSignature with empty labels not to perform allocations")
+	}
+}
+
+func benchmarkMetricToFastFingerprintConc(b *testing.B, ls LabelSet, e Fingerprint, concLevel int) {
+	var start, end sync.WaitGroup
+	start.Add(1)
+	end.Add(concLevel)
+
+	for i := 0; i < concLevel; i++ {
+		go func() {
+			start.Wait()
+			for j := b.N / concLevel; j >= 0; j-- {
+				if a := labelSetToFastFingerprint(ls); a != e {
+					b.Fatalf("expected signature of %d for %s, got %d", e, ls, a)
+				}
+			}
+			end.Done()
+		}()
+	}
+	b.ResetTimer()
+	start.Done()
+	end.Wait()
+}
+
+func BenchmarkMetricToFastFingerprintTripleConc1(b *testing.B) {
+	benchmarkMetricToFastFingerprintConc(b, LabelSet{"first-label": "first-label-value", "second-label": "second-label-value", "third-label": "third-label-value"}, 15738406913934009676, 1)
+}
+
+func BenchmarkMetricToFastFingerprintTripleConc2(b *testing.B) {
+	benchmarkMetricToFastFingerprintConc(b, LabelSet{"first-label": "first-label-value", "second-label": "second-label-value", "third-label": "third-label-value"}, 15738406913934009676, 2)
+}
+
+func BenchmarkMetricToFastFingerprintTripleConc4(b *testing.B) {
+	benchmarkMetricToFastFingerprintConc(b, LabelSet{"first-label": "first-label-value", "second-label": "second-label-value", "third-label": "third-label-value"}, 15738406913934009676, 4)
+}
+
+func BenchmarkMetricToFastFingerprintTripleConc8(b *testing.B) {
+	benchmarkMetricToFastFingerprintConc(b, LabelSet{"first-label": "first-label-value", "second-label": "second-label-value", "third-label": "third-label-value"}, 15738406913934009676, 8)
+}

Godeps/_workspace/src/github.com/prometheus/common/model/time.go

@@ -0,0 +1,232 @@
+// 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 (
+	"fmt"
+	"math"
+	"regexp"
+	"strconv"
+	"strings"
+	"time"
+)
+
+const (
+	// MinimumTick is the minimum supported time resolution. This has to be
+	// at least time.Second in order for the code below to work.
+	minimumTick = time.Millisecond
+	// second is the Time duration equivalent to one second.
+	second = int64(time.Second / minimumTick)
+	// The number of nanoseconds per minimum tick.
+	nanosPerTick = int64(minimumTick / time.Nanosecond)
+
+	// Earliest is the earliest Time representable. Handy for
+	// initializing a high watermark.
+	Earliest = Time(math.MinInt64)
+	// Latest is the latest Time representable. Handy for initializing
+	// a low watermark.
+	Latest = Time(math.MaxInt64)
+)
+
+// Time is the number of milliseconds since the epoch
+// (1970-01-01 00:00 UTC) excluding leap seconds.
+type Time int64
+
+// Interval describes and interval between two timestamps.
+type Interval struct {
+	Start, End Time
+}
+
+// Now returns the current time as a Time.
+func Now() Time {
+	return TimeFromUnixNano(time.Now().UnixNano())
+}
+
+// TimeFromUnix returns the Time equivalent to the Unix Time t
+// provided in seconds.
+func TimeFromUnix(t int64) Time {
+	return Time(t * second)
+}
+
+// TimeFromUnixNano returns the Time equivalent to the Unix Time
+// t provided in nanoseconds.
+func TimeFromUnixNano(t int64) Time {
+	return Time(t / nanosPerTick)
+}
+
+// Equal reports whether two Times represent the same instant.
+func (t Time) Equal(o Time) bool {
+	return t == o
+}
+
+// Before reports whether the Time t is before o.
+func (t Time) Before(o Time) bool {
+	return t < o
+}
+
+// After reports whether the Time t is after o.
+func (t Time) After(o Time) bool {
+	return t > o
+}
+
+// Add returns the Time t + d.
+func (t Time) Add(d time.Duration) Time {
+	return t + Time(d/minimumTick)
+}
+
+// Sub returns the Duration t - o.
+func (t Time) Sub(o Time) time.Duration {
+	return time.Duration(t-o) * minimumTick
+}
+
+// Time returns the time.Time representation of t.
+func (t Time) Time() time.Time {
+	return time.Unix(int64(t)/second, (int64(t)%second)*nanosPerTick)
+}
+
+// Unix returns t as a Unix time, the number of seconds elapsed
+// since January 1, 1970 UTC.
+func (t Time) Unix() int64 {
+	return int64(t) / second
+}
+
+// UnixNano returns t as a Unix time, the number of nanoseconds elapsed
+// since January 1, 1970 UTC.
+func (t Time) UnixNano() int64 {
+	return int64(t) * nanosPerTick
+}
+
+// The number of digits after the dot.
+var dotPrecision = int(math.Log10(float64(second)))
+
+// String returns a string representation of the Time.
+func (t Time) String() string {
+	s := strconv.FormatInt(int64(t), 10)
+	i := len(s) - dotPrecision
+	return s[:i] + "." + s[i:]
+}
+
+// MarshalJSON implements the json.Marshaler interface.
+func (t Time) MarshalJSON() ([]byte, error) {
+	return []byte(t.String()), nil
+}
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (t *Time) UnmarshalJSON(b []byte) error {
+	p := strings.Split(string(b), ".")
+	switch len(p) {
+	case 1:
+		v, err := strconv.ParseInt(string(p[0]), 10, 64)
+		if err != nil {
+			return err
+		}
+		*t = Time(v * second)
+
+	case 2:
+		v, err := strconv.ParseInt(string(p[0]), 10, 64)
+		if err != nil {
+			return err
+		}
+		v *= second
+
+		prec := dotPrecision - len(p[1])
+		if prec < 0 {
+			p[1] = p[1][:dotPrecision]
+		} else if prec > 0 {
+			p[1] = p[1] + strings.Repeat("0", prec)
+		}
+
+		va, err := strconv.ParseInt(p[1], 10, 32)
+		if err != nil {
+			return err
+		}
+
+		*t = Time(v + va)
+
+	default:
+		return fmt.Errorf("invalid time %q", string(b))
+	}
+	return nil
+}
+
+// Duration wraps time.Duration. It is used to parse the custom duration format
+// from YAML.
+// This type should not propagate beyond the scope of input/output processing.
+type Duration time.Duration
+
+// StringToDuration parses a string into a time.Duration, assuming that a year
+// a day always has 24h.
+func ParseDuration(durationStr string) (Duration, error) {
+	matches := durationRE.FindStringSubmatch(durationStr)
+	if len(matches) != 3 {
+		return 0, fmt.Errorf("not a valid duration string: %q", durationStr)
+	}
+	durSeconds, _ := strconv.Atoi(matches[1])
+	dur := time.Duration(durSeconds) * time.Second
+	unit := matches[2]
+	switch unit {
+	case "d":
+		dur *= 60 * 60 * 24
+	case "h":
+		dur *= 60 * 60
+	case "m":
+		dur *= 60
+	case "s":
+		dur *= 1
+	default:
+		return 0, fmt.Errorf("invalid time unit in duration string: %q", unit)
+	}
+	return Duration(dur), nil
+}
+
+var durationRE = regexp.MustCompile("^([0-9]+)([ywdhms]+)$")
+
+func (d Duration) String() string {
+	seconds := int64(time.Duration(d) / time.Second)
+	factors := map[string]int64{
+		"d": 60 * 60 * 24,
+		"h": 60 * 60,
+		"m": 60,
+		"s": 1,
+	}
+	unit := "s"
+	switch int64(0) {
+	case seconds % factors["d"]:
+		unit = "d"
+	case seconds % factors["h"]:
+		unit = "h"
+	case seconds % factors["m"]:
+		unit = "m"
+	}
+	return fmt.Sprintf("%v%v", seconds/factors[unit], unit)
+}
+
+// MarshalYAML implements the yaml.Marshaler interface.
+func (d Duration) MarshalYAML() (interface{}, error) {
+	return d.String(), nil
+}
+
+// UnmarshalYAML implements the yaml.Unmarshaler interface.
+func (d *Duration) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var s string
+	if err := unmarshal(&s); err != nil {
+		return err
+	}
+	dur, err := ParseDuration(s)
+	if err != nil {
+		return err
+	}
+	*d = dur
+	return nil
+}

Godeps/_workspace/src/github.com/prometheus/common/model/time_test.go

@@ -0,0 +1,86 @@
+// 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 (
+	"testing"
+	"time"
+)
+
+func TestComparators(t *testing.T) {
+	t1a := TimeFromUnix(0)
+	t1b := TimeFromUnix(0)
+	t2 := TimeFromUnix(2*second - 1)
+
+	if !t1a.Equal(t1b) {
+		t.Fatalf("Expected %s to be equal to %s", t1a, t1b)
+	}
+	if t1a.Equal(t2) {
+		t.Fatalf("Expected %s to not be equal to %s", t1a, t2)
+	}
+
+	if !t1a.Before(t2) {
+		t.Fatalf("Expected %s to be before %s", t1a, t2)
+	}
+	if t1a.Before(t1b) {
+		t.Fatalf("Expected %s to not be before %s", t1a, t1b)
+	}
+
+	if !t2.After(t1a) {
+		t.Fatalf("Expected %s to be after %s", t2, t1a)
+	}
+	if t1b.After(t1a) {
+		t.Fatalf("Expected %s to not be after %s", t1b, t1a)
+	}
+}
+
+func TestTimeConversions(t *testing.T) {
+	unixSecs := int64(1136239445)
+	unixNsecs := int64(123456789)
+	unixNano := unixSecs*1e9 + unixNsecs
+
+	t1 := time.Unix(unixSecs, unixNsecs-unixNsecs%nanosPerTick)
+	t2 := time.Unix(unixSecs, unixNsecs)
+
+	ts := TimeFromUnixNano(unixNano)
+	if !ts.Time().Equal(t1) {
+		t.Fatalf("Expected %s, got %s", t1, ts.Time())
+	}
+
+	// Test available precision.
+	ts = TimeFromUnixNano(t2.UnixNano())
+	if !ts.Time().Equal(t1) {
+		t.Fatalf("Expected %s, got %s", t1, ts.Time())
+	}
+
+	if ts.UnixNano() != unixNano-unixNano%nanosPerTick {
+		t.Fatalf("Expected %d, got %d", unixNano, ts.UnixNano())
+	}
+}
+
+func TestDuration(t *testing.T) {
+	duration := time.Second + time.Minute + time.Hour
+	goTime := time.Unix(1136239445, 0)
+
+	ts := TimeFromUnix(goTime.Unix())
+	if !goTime.Add(duration).Equal(ts.Add(duration).Time()) {
+		t.Fatalf("Expected %s to be equal to %s", goTime.Add(duration), ts.Add(duration))
+	}
+
+	earlier := ts.Add(-duration)
+	delta := ts.Sub(earlier)
+	if delta != duration {
+		t.Fatalf("Expected %s to be equal to %s", delta, duration)
+	}
+}

Godeps/_workspace/src/github.com/prometheus/common/model/value.go

@@ -0,0 +1,326 @@
+// 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"
+	"sort"
+	"strconv"
+	"strings"
+)
+
+// 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
+}
+
+func (v SampleValue) Equal(o SampleValue) bool {
+	return v == 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
+}
+
+// MarshalJSON implements json.Marshaler.
+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 json.Marshal([...]interface{}{t, v})
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (s *SamplePair) UnmarshalJSON(b []byte) error {
+	if len(b) < 2 || b[0] != '"' || b[len(b)-1] != '"' {
+		return fmt.Errorf("sample pair must be array")
+	}
+
+	b = b[1 : len(b)-1]
+
+	return json.Unmarshal(b, [...]json.Unmarshaler{&s.Timestamp, &s.Value})
+}
+
+// Equal returns true if this SamplePair and o have equal Values and equal
+// Timestamps.
+func (s *SamplePair) Equal(o *SamplePair) bool {
+	return s == o || (s.Value == o.Value && s.Timestamp.Equal(o.Timestamp))
+}
+
+func (s *SamplePair) String() string {
+	return fmt.Sprintf("%s @[%s]", s.Value, s.Timestamp)
+}
+
+// Sample is a sample pair associated with a metric.
+type Sample struct {
+	Metric    Metric
+	Value     SampleValue
+	Timestamp Time
+}
+
+// Equal compares first the metrics, then the timestamp, then the value.
+func (s *Sample) Equal(o *Sample) bool {
+	if s == o {
+		return true
+	}
+
+	if !s.Metric.Equal(o.Metric) {
+		return false
+	}
+	if !s.Timestamp.Equal(o.Timestamp) {
+		return false
+	}
+	if s.Value != o.Value {
+		return false
+	}
+
+	return true
+}
+
+func (s *Sample) String() string {
+	return fmt.Sprintf("%s => %s", s.Metric, SamplePair{
+		Timestamp: s.Timestamp,
+		Value:     s.Value,
+	})
+}
+
+// Samples is a sortable Sample slice. It implements sort.Interface.
+type Samples []*Sample
+
+func (s Samples) Len() int {
+	return len(s)
+}
+
+// Less compares first the metrics, then the timestamp.
+func (s Samples) Less(i, j int) bool {
+	switch {
+	case s[i].Metric.Before(s[j].Metric):
+		return true
+	case s[j].Metric.Before(s[i].Metric):
+		return false
+	case s[i].Timestamp.Before(s[j].Timestamp):
+		return true
+	default:
+		return false
+	}
+}
+
+func (s Samples) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+// Equal compares two sets of samples and returns true if they are equal.
+func (s Samples) Equal(o Samples) bool {
+	if len(s) != len(o) {
+		return false
+	}
+
+	for i, sample := range s {
+		if !sample.Equal(o[i]) {
+			return false
+		}
+	}
+	return true
+}
+
+// SampleStream is a stream of Values belonging to an attached COWMetric.
+type SampleStream struct {
+	Metric Metric       `json:"metric"`
+	Values []SamplePair `json:"values"`
+}
+
+func (ss *SampleStream) String() string {
+	vals := make([]string, len(ss.Values))
+	for i, v := range ss.Values {
+		vals[i] = v.String()
+	}
+	return fmt.Sprintf("%s =>\n%s", ss.Metric, strings.Join(vals, "\n"))
+}
+
+// Value is a generic interface for values resulting from a query evaluation.
+type Value interface {
+	Type() ValueType
+	String() string
+}
+
+func (Matrix) Type() ValueType  { return ValMatrix }
+func (Vector) Type() ValueType  { return ValVector }
+func (*Scalar) Type() ValueType { return ValScalar }
+func (*String) Type() ValueType { return ValString }
+
+type ValueType int
+
+const (
+	ValNone ValueType = iota
+	ValScalar
+	ValVector
+	ValMatrix
+	ValString
+)
+
+// MarshalJSON implements json.Marshaler.
+func (et ValueType) MarshalJSON() ([]byte, error) {
+	return json.Marshal(et.String())
+}
+
+func (et *ValueType) UnmarshalJSON(b []byte) error {
+	var s string
+	if err := json.Unmarshal(b, &s); err != nil {
+		return err
+	}
+	switch s {
+	case "<ValNone>":
+		*et = ValNone
+	case "scalar":
+		*et = ValScalar
+	case "vector":
+		*et = ValVector
+	case "matrix":
+		*et = ValMatrix
+	case "string":
+		*et = ValString
+	default:
+		return fmt.Errorf("unknown value type %q", s)
+	}
+	return nil
+}
+
+func (e ValueType) String() string {
+	switch e {
+	case ValNone:
+		return "<ValNone>"
+	case ValScalar:
+		return "scalar"
+	case ValVector:
+		return "vector"
+	case ValMatrix:
+		return "matrix"
+	case ValString:
+		return "string"
+	}
+	panic("ValueType.String: unhandled value type")
+}
+
+// Scalar is a scalar value evaluated at the set timestamp.
+type Scalar struct {
+	Value     SampleValue `json:"value"`
+	Timestamp Time        `json:"timestamp"`
+}
+
+func (s *Scalar) String() string {
+	return fmt.Sprintf("scalar: %v @[%v]", s.Value, s.Timestamp)
+}
+
+// String is a string value evaluated at the set timestamp.
+type String struct {
+	Value     string `json:"value"`
+	Timestamp Time   `json:"timestamp"`
+}
+
+func (s *String) String() string {
+	return s.Value
+}
+
+// Vector is basically only an alias for Samples, but the
+// contract is that in a Vector, all Samples have the same timestamp.
+type Vector []*Sample
+
+func (vec Vector) String() string {
+	entries := make([]string, len(vec))
+	for i, s := range vec {
+		entries[i] = s.String()
+	}
+	return strings.Join(entries, "\n")
+}
+
+func (vec Vector) Len() int      { return len(vec) }
+func (vec Vector) Swap(i, j int) { vec[i], vec[j] = vec[j], vec[i] }
+
+// Less compares first the metrics, then the timestamp.
+func (vec Vector) Less(i, j int) bool {
+	switch {
+	case vec[i].Metric.Before(vec[j].Metric):
+		return true
+	case vec[j].Metric.Before(vec[i].Metric):
+		return false
+	case vec[i].Timestamp.Before(vec[j].Timestamp):
+		return true
+	default:
+		return false
+	}
+}
+
+// Equal compares two sets of samples and returns true if they are equal.
+func (vec Vector) Equal(o Vector) bool {
+	if len(vec) != len(o) {
+		return false
+	}
+
+	for i, sample := range vec {
+		if !sample.Equal(o[i]) {
+			return false
+		}
+	}
+	return true
+}
+
+// Matrix is a list of time series.
+type Matrix []*SampleStream
+
+func (m Matrix) Len() int           { return len(m) }
+func (m Matrix) Less(i, j int) bool { return m[i].Metric.Before(m[j].Metric) }
+func (m Matrix) Swap(i, j int)      { m[i], m[j] = m[j], m[i] }
+
+func (mat Matrix) String() string {
+	matCp := make(Matrix, len(mat))
+	copy(matCp, mat)
+	sort.Sort(matCp)
+
+	strs := make([]string, len(matCp))
+
+	for i, ss := range matCp {
+		strs[i] = ss.String()
+	}
+
+	return strings.Join(strs, "\n")
+}

Godeps/_workspace/src/github.com/prometheus/common/model/value_test.go

@@ -0,0 +1,114 @@
+// 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 (
+	"sort"
+	"testing"
+)
+
+func TestVectorSort(t *testing.T) {
+	input := Vector{
+		&Sample{
+			Metric: Metric{
+				MetricNameLabel: "A",
+			},
+			Timestamp: 1,
+		},
+		&Sample{
+			Metric: Metric{
+				MetricNameLabel: "A",
+			},
+			Timestamp: 2,
+		},
+		&Sample{
+			Metric: Metric{
+				MetricNameLabel: "C",
+			},
+			Timestamp: 1,
+		},
+		&Sample{
+			Metric: Metric{
+				MetricNameLabel: "C",
+			},
+			Timestamp: 2,
+		},
+		&Sample{
+			Metric: Metric{
+				MetricNameLabel: "B",
+			},
+			Timestamp: 1,
+		},
+		&Sample{
+			Metric: Metric{
+				MetricNameLabel: "B",
+			},
+			Timestamp: 2,
+		},
+	}
+
+	expected := Vector{
+		&Sample{
+			Metric: Metric{
+				MetricNameLabel: "A",
+			},
+			Timestamp: 1,
+		},
+		&Sample{
+			Metric: Metric{
+				MetricNameLabel: "A",
+			},
+			Timestamp: 2,
+		},
+		&Sample{
+			Metric: Metric{
+				MetricNameLabel: "B",
+			},
+			Timestamp: 1,
+		},
+		&Sample{
+			Metric: Metric{
+				MetricNameLabel: "B",
+			},
+			Timestamp: 2,
+		},
+		&Sample{
+			Metric: Metric{
+				MetricNameLabel: "C",
+			},
+			Timestamp: 1,
+		},
+		&Sample{
+			Metric: Metric{
+				MetricNameLabel: "C",
+			},
+			Timestamp: 2,
+		},
+	}
+
+	sort.Sort(input)
+
+	for i, actual := range input {
+		actualFp := actual.Metric.Fingerprint()
+		expectedFp := expected[i].Metric.Fingerprint()
+
+		if actualFp != expectedFp {
+			t.Fatalf("%d. Incorrect fingerprint. Got %s; want %s", i, actualFp.String(), expectedFp.String())
+		}
+
+		if actual.Timestamp != expected[i].Timestamp {
+			t.Fatalf("%d. Incorrect timestamp. Got %s; want %s", i, actual.Timestamp, expected[i].Timestamp)
+		}
+	}
+}