// Execute performs the query represented by the given query string, and returs the result.
func (cmd *SelectCommand) Execute(context ExecutionContext) (interface{}, error) {
timerange, err := api.NewSnappedTimerange(cmd.context.Start, cmd.context.End, cmd.context.Resolution)
if err != nil {
return nil, err
}
hasTimeout := context.Timeout != 0
var cancellable api.Cancellable
if hasTimeout {
cancellable = api.NewTimeoutCancellable(time.Now().Add(context.Timeout))
} else {
cancellable = api.NewCancellable()
}
r := context.Registry
if r == nil {
r = registry.Default()
}
defer close(cancellable.Done()) // broadcast the finish - this ensures that the future work is cancelled.
evaluationContext := function.EvaluationContext{
API: context.API,
FetchLimit: function.NewFetchCounter(context.FetchLimit),
MultiBackend: context.Backend,
Predicate: cmd.predicate,
SampleMethod: cmd.context.SampleMethod,
Timerange: timerange,
Cancellable: cancellable,
Profiler: context.Profiler,
Registry: r,
}
if hasTimeout {
timeout := time.After(context.Timeout)
results := make(chan interface{})
errors := make(chan error)
go func() {
result, err := evaluateExpressions(evaluationContext, cmd.expressions)
if err != nil {
errors <- err
} else {
results <- result
}
}()
select {
case <-timeout:
return nil, fmt.Errorf("Timeout while executing the query.") // timeout.
case result := <-results:
return result, nil
case err := <-errors:
return nil, err
}
} else {
return evaluateExpressions(evaluationContext, cmd.expressions)
}
}
func TestMovingAverage(t *testing.T) {
fakeAPI := mocks.NewFakeMetricMetadataAPI()
fakeAPI.AddPairWithoutGraphite(api.TaggedMetric{"series", api.NewTagSet()})
fakeBackend := movingAverageBackend{}
timerange, err := api.NewTimerange(1200, 1500, 100)
if err != nil {
t.Fatalf(err.Error())
}
expression := &functionExpression{
functionName: "transform.moving_average",
groupBy: []string{},
arguments: []function.Expression{
&metricFetchExpression{"series", api.TruePredicate},
durationExpression{"300ms", 300 * time.Millisecond},
},
}
backend := fakeBackend
result, err := evaluateToSeriesList(expression,
&function.EvaluationContext{
MetricMetadataAPI: fakeAPI,
TimeseriesStorageAPI: backend,
Timerange: timerange,
SampleMethod: api.SampleMean,
FetchLimit: function.NewFetchCounter(1000),
Registry: registry.Default(),
Cancellable: api.NewCancellable(),
OptimizationConfiguration: optimize.NewOptimizationConfiguration(),
})
if err != nil {
t.Errorf(err.Error())
}
expected := []float64{4, 3, 11.0 / 3, 5}
if len(result.Series) != 1 {
t.Fatalf("expected exactly 1 returned series")
}
if len(result.Series[0].Values) != len(expected) {
t.Fatalf("expected exactly %d values in returned series, but got %d", len(expected), len(result.Series[0].Values))
}
const eps = 1e-7
for i := range expected {
if math.Abs(result.Series[0].Values[i]-expected[i]) > eps {
t.Fatalf("expected %+v but got %+v", expected, result.Series[0].Values)
}
}
}
func TestMovingAverage(t *testing.T) {
fakeAPI := mocks.NewFakeApi()
fakeAPI.AddPair(api.TaggedMetric{"series", api.NewTagSet()}, "series")
fakeBackend := movingAverageBackend{}
timerange, err := api.NewTimerange(1200, 1500, 100)
if err != nil {
t.Fatalf(err.Error())
}
expression := &functionExpression{
functionName: "transform.moving_average",
groupBy: []string{},
arguments: []function.Expression{
&metricFetchExpression{"series", api.TruePredicate},
stringExpression{"300ms"},
},
}
result, err := evaluateToSeriesList(expression,
function.EvaluationContext{
API: fakeAPI,
MultiBackend: backend.NewSequentialMultiBackend(fakeBackend),
Timerange: timerange,
SampleMethod: api.SampleMean,
FetchLimit: function.NewFetchCounter(1000),
Registry: registry.Default(),
})
if err != nil {
t.Errorf(err.Error())
}
expected := []float64{4, 3, 11.0 / 3, 5}
if len(result.Series) != 1 {
t.Fatalf("expected exactly 1 returned series")
}
if len(result.Series[0].Values) != len(expected) {
t.Fatalf("expected exactly %d values in returned series", len(expected))
}
const eps = 1e-7
for i := range expected {
if math.Abs(result.Series[0].Values[i]-expected[i]) > eps {
t.Fatalf("expected %+v but got %+v", expected, result.Series[0].Values)
}
}
}
func Test_ScalarExpression(t *testing.T) {
timerangeA, err := api.NewTimerange(0, 10, 2)
if err != nil {
t.Fatalf("invalid timerange used for testcase")
return
}
for _, test := range []struct {
expr scalarExpression
timerange api.Timerange
expectedSeries []api.Timeseries
}{
{
scalarExpression{5},
timerangeA,
[]api.Timeseries{
api.Timeseries{
Values: []float64{5.0, 5.0, 5.0, 5.0, 5.0, 5.0},
TagSet: api.NewTagSet(),
},
},
},
} {
a := assert.New(t).Contextf("%+v", test)
result, err := evaluateToSeriesList(test.expr, &function.EvaluationContext{
TimeseriesStorageAPI: FakeBackend{},
Timerange: test.timerange,
SampleMethod: api.SampleMean,
FetchLimit: function.NewFetchCounter(1000),
Registry: registry.Default(),
})
if err != nil {
t.Fatalf("failed to convert number into serieslist")
}
a.EqInt(len(result.Series), len(test.expectedSeries))
for i := 0; i < len(result.Series); i++ {
a.Eq(result.Series[i].Values, test.expectedSeries[i].Values)
}
}
}
func Test_evaluateBinaryOperation(t *testing.T) {
emptyContext := &function.EvaluationContext{
TimeseriesStorageAPI: FakeBackend{},
MetricMetadataAPI: nil,
Timerange: api.Timerange{},
SampleMethod: api.SampleMean,
Predicate: nil,
FetchLimit: function.NewFetchCounter(1000),
Cancellable: api.NewCancellable(),
}
for _, test := range []struct {
context *function.EvaluationContext
functionName string
left api.SeriesList
right api.SeriesList
evalFunction func(float64, float64) float64
expectSuccess bool
expectedResultValues [][]float64
}{
{
emptyContext,
"add",
api.SeriesList{
[]api.Timeseries{
{
Values: []float64{1, 2, 3},
TagSet: api.TagSet{},
},
},
api.Timerange{},
"",
"",
},
api.SeriesList{
[]api.Timeseries{
{
Values: []float64{4, 5, 1},
TagSet: api.TagSet{},
},
},
api.Timerange{},
"",
"",
},
func(left, right float64) float64 { return left + right },
true,
[][]float64{{5, 7, 4}},
},
{
emptyContext,
"subtract",
api.SeriesList{
[]api.Timeseries{
{
Values: []float64{1, 2, 3},
},
},
api.Timerange{},
"",
"",
},
api.SeriesList{
[]api.Timeseries{
{
Values: []float64{4, 5, 1},
},
},
api.Timerange{},
"",
"",
},
func(left, right float64) float64 { return left - right },
true,
[][]float64{{-3, -3, 2}},
},
{
emptyContext,
"add",
api.SeriesList{
[]api.Timeseries{
api.Timeseries{
Values: []float64{1, 2, 3},
TagSet: api.TagSet{
"env": "production",
"host": "#1",
},
},
api.Timeseries{
Values: []float64{7, 7, 7},
TagSet: api.TagSet{
"env": "staging",
"host": "#2",
},
},
api.Timeseries{
Values: []float64{1, 0, 2},
TagSet: api.TagSet{
"env": "staging",
"host": "#3",
},
},
},
api.Timerange{},
"",
"",
},
api.SeriesList{
[]api.Timeseries{
api.Timeseries{
Values: []float64{5, 5, 5},
TagSet: api.TagSet{
"env": "staging",
},
},
api.Timeseries{
Values: []float64{10, 100, 1000},
TagSet: api.TagSet{
"env": "production",
},
},
},
api.Timerange{},
"",
"",
},
func(left, right float64) float64 { return left + right },
true,
[][]float64{{11, 102, 1003}, {12, 12, 12}, {6, 5, 7}},
},
{
emptyContext,
"add",
api.SeriesList{
[]api.Timeseries{
api.Timeseries{
Values: []float64{1, 2, 3},
TagSet: api.TagSet{
"env": "production",
"host": "#1",
},
},
api.Timeseries{
Values: []float64{4, 5, 6},
TagSet: api.TagSet{
"env": "staging",
"host": "#2",
},
},
api.Timeseries{
Values: []float64{7, 8, 9},
TagSet: api.TagSet{
"env": "staging",
"host": "#3",
},
},
},
api.Timerange{},
"",
"",
},
api.SeriesList{
[]api.Timeseries{
api.Timeseries{
Values: []float64{2, 2, 2},
TagSet: api.TagSet{
"env": "staging",
},
},
api.Timeseries{
Values: []float64{3, 3, 3},
TagSet: api.TagSet{
"env": "staging",
},
},
},
api.Timerange{},
"",
"",
},
func(left, right float64) float64 { return left * right },
true,
[][]float64{{8, 10, 12}, {14, 16, 18}, {12, 15, 18}, {21, 24, 27}},
},
{
emptyContext,
"add",
api.SeriesList{
[]api.Timeseries{
api.Timeseries{
Values: []float64{103, 103, 103},
TagSet: api.TagSet{
"env": "production",
"host": "#1",
},
},
api.Timeseries{
Values: []float64{203, 203, 203},
TagSet: api.TagSet{
"env": "staging",
"host": "#2",
},
},
api.Timeseries{
Values: []float64{303, 303, 303},
TagSet: api.TagSet{
"env": "staging",
"host": "#3",
},
},
},
api.Timerange{},
"",
"",
},
api.SeriesList{
[]api.Timeseries{
api.Timeseries{
Values: []float64{1, 2, 3},
TagSet: api.TagSet{
"env": "staging",
},
},
api.Timeseries{
Values: []float64{3, 0, 3},
TagSet: api.TagSet{
"env": "production",
},
},
},
api.Timerange{},
"",
"",
},
func(left, right float64) float64 { return left - right },
true,
[][]float64{{100, 103, 100}, {202, 201, 200}, {302, 301, 300}},
},
} {
a := assert.New(t).Contextf("%+v", test)
metricFun := registry.NewOperator(test.functionName, test.evalFunction)
value, err := metricFun.Evaluate(test.context, []function.Expression{&LiteralSeriesExpression{test.left}, &LiteralSeriesExpression{test.right}}, []string{}, false)
if err != nil {
a.EqBool(err == nil, test.expectSuccess)
continue
}
result, err := value.ToSeriesList(test.context.Timerange)
if err != nil {
a.EqBool(err == nil, test.expectSuccess)
continue
}
// Our expected list should be the same length as the actual one:
a.EqInt(len(result.Series), len(test.expectedResultValues))
// The "expected" results are only true up to permutation (since guessing the order they'll come out of `join()` is hard)
// Provided that they're all unique then we just need to check that every member that's expected can be found
// This is a bit more annoying:
equal := func(left, right []float64) bool {
if len(left) != len(right) {
return false
}
for i := range left {
if left[i] != right[i] {
return false
}
}
return true
}
for _, expectedMember := range test.expectedResultValues {
found := false
// check that expectedMember is inside our result list
// look for it inside result.Series
for _, resultMember := range result.Series {
if equal(resultMember.Values, expectedMember) {
found = true
break
}
}
if !found {
t.Fatalf("got %+v for test %+v", result, test)
}
}
}
}
// Execute performs the query represented by the given query string, and returs the result.
func (cmd *SelectCommand) Execute(context ExecutionContext) (interface{}, error) {
timerange, err := api.NewSnappedTimerange(cmd.context.Start, cmd.context.End, cmd.context.Resolution)
if err != nil {
return nil, err
}
slotLimit := context.SlotLimit
defaultLimit := 1000
if slotLimit == 0 {
slotLimit = defaultLimit // the default limit
}
smallestResolution := timerange.Duration() / time.Duration(slotLimit-2)
// ((end + res/2) - (start - res/2)) / res + 1 <= slots // make adjustments for a snap that moves the endpoints
// (do some algebra)
// (end - start + res) + res <= slots * res
// end - start <= res * (slots - 2)
// so
// res >= (end - start) / (slots - 2)
// Update the timerange by applying the insights of the storage API:
chosenResolution := context.TimeseriesStorageAPI.ChooseResolution(timerange, smallestResolution)
chosenTimerange, err := api.NewSnappedTimerange(timerange.Start(), timerange.End(), int64(chosenResolution/time.Millisecond))
if err != nil {
return nil, err
}
if chosenTimerange.Slots() > slotLimit {
return nil, function.NewLimitError(
"Requested number of data points exceeds the configured limit",
chosenTimerange.Slots(), slotLimit)
}
hasTimeout := context.Timeout != 0
var cancellable api.Cancellable
if hasTimeout {
cancellable = api.NewTimeoutCancellable(time.Now().Add(context.Timeout))
} else {
cancellable = api.NewCancellable()
}
r := context.Registry
if r == nil {
r = registry.Default()
}
defer close(cancellable.Done()) // broadcast the finish - this ensures that the future work is cancelled.
evaluationContext := function.EvaluationContext{
MetricMetadataAPI: context.MetricMetadataAPI,
FetchLimit: function.NewFetchCounter(context.FetchLimit),
TimeseriesStorageAPI: context.TimeseriesStorageAPI,
Predicate: cmd.predicate,
SampleMethod: cmd.context.SampleMethod,
Timerange: timerange,
Cancellable: cancellable,
Registry: r,
Profiler: context.Profiler,
OptimizationConfiguration: context.OptimizationConfiguration,
}
if hasTimeout {
timeout := time.After(context.Timeout)
results := make(chan interface{})
errors := make(chan error)
go func() {
result, err := function.EvaluateMany(evaluationContext, cmd.expressions)
if err != nil {
errors <- err
} else {
results <- result
}
}()
select {
case <-timeout:
return nil, function.NewLimitError("Timeout while executing the query.",
context.Timeout, context.Timeout)
case result := <-results:
return result, nil
case err := <-errors:
return nil, err
}
} else {
values, err := function.EvaluateMany(evaluationContext, cmd.expressions)
if err != nil {
return nil, err
}
lists := make([]api.SeriesList, len(values))
for i := range values {
lists[i], err = values[i].ToSeriesList(evaluationContext.Timerange)
if err != nil {
return nil, err
}
}
return lists, nil
}
}
// Execute performs the query represented by the given query string, and returs the result.
func (cmd *SelectCommand) Execute(context ExecutionContext) (interface{}, error) {
timerange, err := api.NewSnappedTimerange(cmd.context.Start, cmd.context.End, cmd.context.Resolution)
if err != nil {
return nil, err
}
slotLimit := context.SlotLimit
defaultLimit := 1000
if slotLimit == 0 {
slotLimit = defaultLimit // the default limit
}
if timerange.Slots() > slotLimit {
return nil, function.NewLimitError(
"Requested number of data points exceeds the configured limit",
timerange.Slots(), slotLimit)
}
hasTimeout := context.Timeout != 0
var cancellable api.Cancellable
if hasTimeout {
cancellable = api.NewTimeoutCancellable(time.Now().Add(context.Timeout))
} else {
cancellable = api.NewCancellable()
}
r := context.Registry
if r == nil {
r = registry.Default()
}
defer close(cancellable.Done()) // broadcast the finish - this ensures that the future work is cancelled.
evaluationContext := function.EvaluationContext{
API: context.API,
FetchLimit: function.NewFetchCounter(context.FetchLimit),
MultiBackend: context.Backend,
Predicate: cmd.predicate,
SampleMethod: cmd.context.SampleMethod,
Timerange: timerange,
Cancellable: cancellable,
Profiler: context.Profiler,
Registry: r,
}
if hasTimeout {
timeout := time.After(context.Timeout)
results := make(chan interface{})
errors := make(chan error)
go func() {
result, err := function.EvaluateMany(evaluationContext, cmd.expressions)
if err != nil {
errors <- err
} else {
results <- result
}
}()
select {
case <-timeout:
return nil, function.NewLimitError("Timeout while executing the query.",
context.Timeout, context.Timeout)
case result := <-results:
return result, nil
case err := <-errors:
return nil, err
}
} else {
values, err := function.EvaluateMany(evaluationContext, cmd.expressions)
if err != nil {
return nil, err
}
lists := make([]api.SeriesList, len(values))
for i := range values {
lists[i], err = values[i].ToSeriesList(evaluationContext.Timerange)
if err != nil {
return nil, err
}
}
return lists, nil
}
}
// Execute performs the query represented by the given query string, and returs the result.
func (cmd *SelectCommand) Execute(context ExecutionContext) (CommandResult, error) {
userTimerange, err := api.NewSnappedTimerange(cmd.context.Start, cmd.context.End, cmd.context.Resolution)
if err != nil {
return CommandResult{}, err
}
slotLimit := context.SlotLimit
defaultLimit := 1000
if slotLimit == 0 {
slotLimit = defaultLimit // the default limit
}
smallestResolution := userTimerange.Duration() / time.Duration(slotLimit-2)
// ((end + res/2) - (start - res/2)) / res + 1 <= slots // make adjustments for a snap that moves the endpoints
// (do some algebra)
// (end - start + res) + res <= slots * res
// end - start <= res * (slots - 2)
// so
// res >= (end - start) / (slots - 2)
// Update the timerange by applying the insights of the storage API:
chosenResolution := context.TimeseriesStorageAPI.ChooseResolution(userTimerange, smallestResolution)
chosenTimerange, err := api.NewSnappedTimerange(userTimerange.Start(), userTimerange.End(), int64(chosenResolution/time.Millisecond))
if err != nil {
return CommandResult{}, err
}
if chosenTimerange.Slots() > slotLimit {
return CommandResult{}, function.NewLimitError(
"Requested number of data points exceeds the configured limit",
chosenTimerange.Slots(), slotLimit)
}
hasTimeout := context.Timeout != 0
var cancellable api.Cancellable
if hasTimeout {
cancellable = api.NewTimeoutCancellable(time.Now().Add(context.Timeout))
} else {
cancellable = api.NewCancellable()
}
r := context.Registry
if r == nil {
r = registry.Default()
}
defer close(cancellable.Done()) // broadcast the finish - this ensures that the future work is cancelled.
evaluationContext := function.EvaluationContext{
MetricMetadataAPI: context.MetricMetadataAPI,
FetchLimit: function.NewFetchCounter(context.FetchLimit),
TimeseriesStorageAPI: context.TimeseriesStorageAPI,
Predicate: cmd.predicate,
SampleMethod: cmd.context.SampleMethod,
Timerange: chosenTimerange,
Cancellable: cancellable,
Registry: r,
Profiler: context.Profiler,
OptimizationConfiguration: context.OptimizationConfiguration,
EvaluationNotes: []string{},
UserSpecifiableConfig: context.UserSpecifiableConfig,
}
timeout := (<-chan time.Time)(nil)
if hasTimeout {
// A nil channel will just block forever
timeout = time.After(context.Timeout)
}
results := make(chan []function.Value, 1)
errors := make(chan error, 1)
// Goroutines are never garbage collected, so we need to provide capacity so that the send always succeeds.
go func() {
// Evaluate the result, and send it along the goroutines.
result, err := function.EvaluateMany(&evaluationContext, cmd.expressions)
if err != nil {
errors <- err
return
}
results <- result
}()
select {
case <-timeout:
return CommandResult{}, function.NewLimitError("Timeout while executing the query.",
context.Timeout, context.Timeout)
case err := <-errors:
return CommandResult{}, err
case result := <-results:
lists := make([]api.SeriesList, len(result))
for i := range result {
lists[i], err = result[i].ToSeriesList(evaluationContext.Timerange)
if err != nil {
return CommandResult{}, err
}
}
description := map[string][]string{}
for _, list := range lists {
for _, series := range list.Series {
for key, value := range series.TagSet {
description[key] = append(description[key], value)
}
}
}
for key, values := range description {
natural_sort.Sort(values)
filtered := []string{}
for i := range values {
if i == 0 || values[i-1] != values[i] {
filtered = append(filtered, values[i])
}
}
description[key] = filtered
}
return CommandResult{
Body: lists,
Metadata: map[string]interface{}{
"description": description,
"notes": evaluationContext.EvaluationNotes,
},
}, nil
}
}