golib: github.com/signalfx/golib/sfxclient Index | Examples | Files | Directories

package sfxclient

import "github.com/signalfx/golib/sfxclient"

Package sfxclient creates convenient go functions and wrappers to send metrics to SignalFx.

The core of the library is HTTPSink which allows users to send metrics and events to SignalFx ad-hoc. A Scheduler is built on top of this to facility easy management of metrics for multiple SignalFx reporters at once in more complex libraries.


The simplest way to send metrics and events to SignalFx is with HTTPSink. The only struct parameter that needs to be configured is AuthToken. To make it easier to create common Datapoint objects, wrappers exist for Gauge and Cumulative. An example of sending a hello world metric would look like this:

func SendHelloWorld() {
    client := NewHTTPSink()
    client.AuthToken = "ABCDXYZ"
    ctx := context.Background()
    client.AddDatapoints(ctx, []*datapoint.Datapoint{
        GaugeF("hello.world", nil, 1.0),


To facilitate periodic sending of datapoints to SignalFx, a Scheduler abstraction exists. You can use this to report custom metrics to SignalFx at some periodic interval.

type CustomApplication struct {
    queue chan int64
func (c *CustomApplication) Datapoints() []*datapoint.Datapoint {
    return []*datapoint.Datapoint {
      sfxclient.Gauge("queue.size", nil, len(queue)),
func main() {
    scheduler := sfxclient.NewScheduler()
    scheduler.Sink.(*HTTPSink).AuthToken = "ABCD-XYZ"
    app := &CustomApplication{}
    go scheduler.Schedule(context.Background())

RollingBucket and CumulativeBucket

Because counting things and calculating percentiles like p99 or median are common operations, RollingBucket and CumulativeBucket exist to make this easier. They implement the Collector interface which allows users to add them to an existing Scheduler.

To run integration tests, testing sending to SignalFx with an actual token, create a file named authinfo.json that has your auth Token, similar to the following

  "AuthToken": "abcdefg"

Then execute the following:

go test -v --tags=integration -run TestDatapointSending ./sfxclient/



Package Files

cumulativebucket.go datapointcreation.go gometrics.go httpsink.go multitokensink.go rollbucket.go sfxclient.go timerange.go wrapper.go


const (
    // ClientVersion is the version of this library and is embedded into the user agent
    ClientVersion = "1.0"

    // IngestEndpointV2 is the v2 version of the signalfx ingest endpoint
    IngestEndpointV2 = "https://ingest.signalfx.com/v2/datapoint"

    // EventIngestEndpointV2 is the v2 version of the signalfx event endpoint
    EventIngestEndpointV2 = "https://ingest.signalfx.com/v2/event"

    // TraceIngestEndpointV1 is the v1 version of the signalfx trace endpoint
    TraceIngestEndpointV1 = "https://ingest.signalfx.com/v1/trace"

    // DefaultTimeout is the default time to fail signalfx datapoint requests if they don't succeed
    DefaultTimeout = time.Second * 5
const (
    // DefaultReportingDelay is the default interval Scheduler users to report metrics to SignalFx
    DefaultReportingDelay = time.Second * 20
    // DefaultReportingTimeout is the default timeout value for Scheduler to log error message if reporting is not completed within this duration
    DefaultReportingTimeout = time.Second * 5
const TokenHeaderName = "X-Sf-Token"

TokenHeaderName is the header key for the auth token in the HTTP request


var (
    // XDebugID Debugs the transaction via signalscope if value matches known secret
    XDebugID xKeyContextValue = "X-Debug-Id"
    // XTracingDebug Sets debug flag on trace if value matches known secret
    XTracingDebug xKeyContextValue = "X-SF-Trace-Token"
    // XTracingID if set accompanies the tracingDebug and gives a client the ability to put a value into a tag on the ingest span
    XTracingID xKeyContextValue = "X-SF-Tracing-ID"
var DefaultBucketWidth = time.Second * 20

DefaultBucketWidth is the default width that a RollingBucket should flush histogram values

var DefaultErrorHandler = func(err error) error {
    log.DefaultLogger.Log(log.Err, err, "Unable to handle error")
    return nil

DefaultErrorHandler is the default way to handle errors by a scheduler. It simply prints them to stdout

var DefaultHistogramSize = 80

DefaultHistogramSize is the default number of windows RollingBucket uses for created histograms

var DefaultMaxBufferSize = 100

DefaultMaxBufferSize is the default number of past bucket Quantile values RollingBucket saves until a Datapoints() call

var DefaultQuantiles = []float64{.25, .5, .9, .99}

DefaultQuantiles are the default set of percentiles RollingBucket should collect

var DefaultUserAgent = fmt.Sprintf("golib-sfxclient/%s (gover %s)", ClientVersion, runtime.Version())

DefaultUserAgent is the UserAgent string sent to signalfx

func Counter Uses

func Counter(metricName string, dimensions map[string]string, val int64) *datapoint.Datapoint

Counter creates a SignalFx counter for integer values, incrementing by a set value. Generally, it is preferable to use Cumulative Counters when possible.

func Cumulative Uses

func Cumulative(metricName string, dimensions map[string]string, val int64) *datapoint.Datapoint

Cumulative creates a SignalFx cumulative counter for integer values.

func CumulativeF Uses

func CumulativeF(metricName string, dimensions map[string]string, val float64) *datapoint.Datapoint

CumulativeF creates a SignalFx cumulative counter for float values.

func CumulativeP Uses

func CumulativeP(metricName string, dimensions map[string]string, val *int64) *datapoint.Datapoint

CumulativeP creates a SignalFx cumulative counter for integer values from a pointer that is loaded atomically.


client := NewHTTPSink()
ctx := context.Background()
var countThing int64
go func() {
    atomic.AddInt64(&countThing, 1)
if err := client.AddDatapoints(ctx, []*datapoint.Datapoint{
    CumulativeP("server.request_count", nil, &countThing),
}); err != nil {
    panic("Could not send datapoints")

func Gauge Uses

func Gauge(metricName string, dimensions map[string]string, val int64) *datapoint.Datapoint

Gauge creates a SignalFx gauge for integer values.

func GaugeF Uses

func GaugeF(metricName string, dimensions map[string]string, val float64) *datapoint.Datapoint

GaugeF creates a SignalFx gauge for floating point values.

type AsyncMultiTokenSink Uses

type AsyncMultiTokenSink struct {
    ShutdownTimeout time.Duration // ShutdownTimeout is how long the sink should wait before timing out after Close() is called

    Hasher hash.Hash32 // Hasher is used to hash access tokens to a worker

    NewHTTPClient func() *http.Client // function used to create an http client for the underlying sinks
    // contains filtered or unexported fields

AsyncMultiTokenSink asynchronously sends datapoints for multiple tokens

func NewAsyncMultiTokenSink Uses

func NewAsyncMultiTokenSink(numChannels int64, numDrainingThreads int64, buffer int, batchSize int, datapointEndpoint, eventEndpoint, traceEndpoint, userAgent string, httpClient func() *http.Client, errorHandler func(error) error, maxRetry int) *AsyncMultiTokenSink

NewAsyncMultiTokenSink returns a sink that asynchronously emits datapoints with different tokens

func (*AsyncMultiTokenSink) AddDatapoints Uses

func (a *AsyncMultiTokenSink) AddDatapoints(ctx context.Context, datapoints []*datapoint.Datapoint) (err error)

AddDatapoints add datepoints to the multitoken sync using a context that has the TokenCtxKey

func (*AsyncMultiTokenSink) AddDatapointsWithToken Uses

func (a *AsyncMultiTokenSink) AddDatapointsWithToken(token string, datapoints []*datapoint.Datapoint) (err error)

AddDatapointsWithToken emits a list of datapoints using a supplied token

func (*AsyncMultiTokenSink) AddEvents Uses

func (a *AsyncMultiTokenSink) AddEvents(ctx context.Context, events []*event.Event) (err error)

AddEvents add datepoints to the multitoken sync using a context that has the TokenCtxKey

func (*AsyncMultiTokenSink) AddEventsWithToken Uses

func (a *AsyncMultiTokenSink) AddEventsWithToken(token string, events []*event.Event) (err error)

AddEventsWithToken emits a list of events using a supplied token

func (*AsyncMultiTokenSink) AddSpans Uses

func (a *AsyncMultiTokenSink) AddSpans(ctx context.Context, spans []*trace.Span) (err error)

AddSpans add datepoints to the multitoken sync using a context that has the TokenCtxKey

func (*AsyncMultiTokenSink) AddSpansWithToken Uses

func (a *AsyncMultiTokenSink) AddSpansWithToken(token string, spans []*trace.Span) (err error)

AddSpansWithToken emits a list of events using a supplied token

func (*AsyncMultiTokenSink) Close Uses

func (a *AsyncMultiTokenSink) Close() (err error)

Close stops the existing workers and prevents additional datapoints from being added if a ShutdownTimeout is set on the sink, it will be used as a timeout for closing the sink the default timeout is 5 seconds

func (*AsyncMultiTokenSink) Datapoints Uses

func (a *AsyncMultiTokenSink) Datapoints() (dps []*datapoint.Datapoint)

Datapoints returns a set of datapoints about the sink

type AsyncTokenStatusCounter Uses

type AsyncTokenStatusCounter struct {
    // contains filtered or unexported fields

AsyncTokenStatusCounter is a counter and collector for http statuses by token

func NewAsyncTokenStatusCounter Uses

func NewAsyncTokenStatusCounter(name string, buffer int, numWorkers int64, defaultDims map[string]string) *AsyncTokenStatusCounter

NewAsyncTokenStatusCounter returns a structure for counting occurrences of http statuses by token

func (*AsyncTokenStatusCounter) Datapoints Uses

func (a *AsyncTokenStatusCounter) Datapoints() (dps []*datapoint.Datapoint)

Datapoints returns datapoints for each token and status

func (*AsyncTokenStatusCounter) Increment Uses

func (a *AsyncTokenStatusCounter) Increment(status *tokenStatus)

Increment adds a tokenStatus object to the counter

type Collector Uses

type Collector interface {
    Datapoints() []*datapoint.Datapoint

Collector is anything Scheduler can track that emits points

var GoMetricsSource Collector = &goMetrics{}

GoMetricsSource is a singleton Collector that collects basic go system stats. It currently collects from runtime.ReadMemStats and adds a few extra metrics like uptime of the process and other runtime package functions.

func NewMultiCollector Uses

func NewMultiCollector(collectors ...Collector) Collector

NewMultiCollector returns a collector that is the aggregate of every given collector. It can be used to turn multiple collectors into a single collector.


var a Collector
var b Collector
c := NewMultiCollector(a, b)

type ContextKey Uses

type ContextKey string

ContextKey is a custom key type for context values

const (
    // TokenCtxKey is a context key for tokens
    TokenCtxKey ContextKey = TokenHeaderName

type CumulativeBucket Uses

type CumulativeBucket struct {
    MetricName string
    Dimensions map[string]string
    // contains filtered or unexported fields

A CumulativeBucket tracks groups of values, reporting the count/sum/sum of squares as a cumulative counter.


cb := &CumulativeBucket{
    MetricName: "mname",
    Dimensions: map[string]string{"type": "dev"},
client := NewHTTPSink()
ctx := context.Background()
// Will expect it to send count=2, sum=4, sumofsquare=10
log.IfErr(log.Panic, client.AddDatapoints(ctx, cb.Datapoints()))

func (*CumulativeBucket) Add Uses

func (b *CumulativeBucket) Add(val int64)

Add an item to the bucket, later reporting the result in the next report cycle.

func (*CumulativeBucket) Datapoints Uses

func (b *CumulativeBucket) Datapoints() []*datapoint.Datapoint

Datapoints returns the count/sum/sumsquare datapoints, or nil if there is no set metric name

func (*CumulativeBucket) MultiAdd Uses

func (b *CumulativeBucket) MultiAdd(res *Result)

MultiAdd many items into the bucket at once using a Result. This can be more efficient as it involves only a constant number of atomic operations.

type HTTPSink Uses

type HTTPSink struct {
    AuthToken         string
    UserAgent         string
    EventEndpoint     string
    DatapointEndpoint string
    TraceEndpoint     string
    AdditionalHeaders map[string]string
    ResponseCallback  func(resp *http.Response, responseBody []byte)
    Client            *http.Client

    DisableCompression bool
    // contains filtered or unexported fields

HTTPSink -


sink := NewHTTPSink()
sink.AuthToken = "ABCDEFG"
ctx := context.Background()
err := sink.AddDatapoints(ctx, []*datapoint.Datapoint{
    // Sending a gauge with the value 1.2
    GaugeF("a.gauge", nil, 1.2),
    // Sending a cumulative counter with dimensions
    Cumulative("a.counter", map[string]string{"type": "dev"}, 100),
if err != nil {

func NewHTTPSink Uses

func NewHTTPSink() *HTTPSink

NewHTTPSink creates a default NewHTTPSink using package level constants as defaults, including an empty auth token. If sending directly to SignalFx, you will be required to explicitly set the AuthToken

func (*HTTPSink) AddDatapoints Uses

func (h *HTTPSink) AddDatapoints(ctx context.Context, points []*datapoint.Datapoint) (err error)

AddDatapoints forwards the datapoints to SignalFx.

func (*HTTPSink) AddEvents Uses

func (h *HTTPSink) AddEvents(ctx context.Context, events []*event.Event) (err error)

AddEvents forwards the events to SignalFx.

func (*HTTPSink) AddSpans Uses

func (h *HTTPSink) AddSpans(ctx context.Context, traces []*trace.Span) (err error)

AddSpans forwards the traces to SignalFx.

type HashableCollector Uses

type HashableCollector struct {
    Callback func() []*datapoint.Datapoint

HashableCollector is a Collector function that can be inserted into a hashmap. You can use it to wrap a functional callback and insert it into a Scheduler.

func CollectorFunc Uses

func CollectorFunc(callback func() []*datapoint.Datapoint) *HashableCollector

CollectorFunc wraps a function to make it a Collector.

func (*HashableCollector) Datapoints Uses

func (h *HashableCollector) Datapoints() []*datapoint.Datapoint

Datapoints calls the wrapped function.

type MultiCollector Uses

type MultiCollector []Collector

MultiCollector acts like a datapoint collector over multiple collectors.

func (MultiCollector) Datapoints Uses

func (m MultiCollector) Datapoints() []*datapoint.Datapoint

Datapoints returns the datapoints from every collector.

type Result Uses

type Result struct {
    Count        int64
    Sum          int64
    SumOfSquares float64

Result is a cumulated result of items that can be added to a CumulativeBucket at once

func (*Result) Add Uses

func (r *Result) Add(val int64)

Add a single number to the bucket. This does not use atomic operations and is not thread safe, but adding a finished Result into a CumulativeBucket is thread safe.

type RollingBucket Uses

type RollingBucket struct {
    // MetricName is the metric name used when the RollingBucket is reported to SignalFx
    MetricName string
    // Dimensions are the dimensions used when the RollingBucket is reported to SignalFx
    Dimensions map[string]string
    // Quantiles are an array of values [0 - 1.0] that are the histogram quantiles reported to
    // SignalFx during a Datapoints() call.  For example, [.5] would only report the median.
    Quantiles []float64
    // BucketWidth is how long in time a bucket accumulates values before a flush is forced
    BucketWidth time.Duration
    // Hist is an efficient tracker of numeric values for a histogram
    Hist *gohistogram.NumericHistogram
    // MaxFlushBufferSize is the maximum size of a window to keep for the RollingBucket before
    // quantiles are dropped.  It is ideally close to len(quantiles) * 3 + 15
    MaxFlushBufferSize int
    // Timer is used to track time.Now() during default value add calls
    Timer timekeeper.TimeKeeper
    // contains filtered or unexported fields

RollingBucket keeps histogram style metrics over a BucketWidth window of time. It allows users to collect and report percentile metrics like like median or p99, as well as min/max/sum/count and sum of square from a set of points.

func NewRollingBucket Uses

func NewRollingBucket(metricName string, dimensions map[string]string) *RollingBucket

NewRollingBucket creates a new RollingBucket using default values for Quantiles, BucketWidth, and the histogram tracker.

func (*RollingBucket) Add Uses

func (r *RollingBucket) Add(v float64)

Add a value to the rolling bucket histogram. If the current time is already calculated, it may be more efficient to call AddAt in order to save another time.Time() call.

func (*RollingBucket) AddAt Uses

func (r *RollingBucket) AddAt(v float64, t time.Time)

AddAt is like Add but also takes a time to pretend the value comes at.

func (*RollingBucket) Datapoints Uses

func (r *RollingBucket) Datapoints() []*datapoint.Datapoint

Datapoints returns basic bucket stats every time and will only the first time called for each window return that window's points. For efficiency sake, Datapoints() will only return histogram window values once. Because of this, it is suggested to always forward datapoints returned by this call to SignalFx.

type SFXAPIError Uses

type SFXAPIError struct {
    StatusCode   int
    ResponseBody string

SFXAPIError is returned when the API returns a status code other than 200.

func (SFXAPIError) Error Uses

func (se SFXAPIError) Error() string

type Scheduler Uses

type Scheduler struct {
    Sink         Sink
    Timer        timekeeper.TimeKeeper
    SendZeroTime bool

    ErrorHandler       func(error) error
    ReportingDelayNs   int64
    ReportingTimeoutNs int64

    Prefix string
    // contains filtered or unexported fields

A Scheduler reports metrics to SignalFx at some timely manner.


s := NewScheduler()
s.Sink.(*HTTPSink).AuthToken = "ABCD-XYZ"
bucket := NewRollingBucket("req.time", map[string]string{"env": "test"})
ctx := context.Background()
err := s.Schedule(ctx)
fmt.Println("Schedule result: ", err)

func NewScheduler Uses

func NewScheduler() *Scheduler

NewScheduler creates a default SignalFx scheduler that can report metrics to SignalFx at some interval.

func (*Scheduler) AddCallback Uses

func (s *Scheduler) AddCallback(db Collector)

AddCallback adds a collector to the default group.

func (*Scheduler) AddGroupedCallback Uses

func (s *Scheduler) AddGroupedCallback(group string, db Collector)

AddGroupedCallback adds a collector to a specific group.

func (*Scheduler) CollectDatapoints Uses

func (s *Scheduler) CollectDatapoints() []*datapoint.Datapoint

CollectDatapoints gives a scheduler an external endpoint to be called and is thread safe

func (*Scheduler) Debug Uses

func (s *Scheduler) Debug(debug bool)

Debug used for debugging collectDatapoints()

func (*Scheduler) DefaultDimensions Uses

func (s *Scheduler) DefaultDimensions(dims map[string]string)

DefaultDimensions adds a dimension map that are appended to all metrics in the default group.

func (*Scheduler) GroupedDefaultDimensions Uses

func (s *Scheduler) GroupedDefaultDimensions(group string, dims map[string]string)

GroupedDefaultDimensions adds default dimensions to a specific group.

func (*Scheduler) RemoveCallback Uses

func (s *Scheduler) RemoveCallback(db Collector)

RemoveCallback removes a collector from the default group.

func (*Scheduler) RemoveGroupedCallback Uses

func (s *Scheduler) RemoveGroupedCallback(group string, db Collector)

RemoveGroupedCallback removes a collector from a specific group.

func (*Scheduler) ReportOnce Uses

func (s *Scheduler) ReportOnce(ctx context.Context) error

ReportOnce will report any metrics saved in this reporter to SignalFx

func (*Scheduler) ReportingDelay Uses

func (s *Scheduler) ReportingDelay(delay time.Duration)

ReportingDelay sets the interval metrics are reported to SignalFx.

func (*Scheduler) ReportingTimeout Uses

func (s *Scheduler) ReportingTimeout(timeout time.Duration)

ReportingTimeout sets the timeout value if reporting to SignalFx is not completed within this duration

func (*Scheduler) Schedule Uses

func (s *Scheduler) Schedule(ctx context.Context) error

Schedule will run until either the ErrorHandler returns an error or the context is canceled. This is intended to be run inside a goroutine.

func (*Scheduler) Var Uses

func (s *Scheduler) Var() expvar.Var

Var returns an expvar variable that prints the values of the previously reported datapoints.

type Sink Uses

type Sink interface {
    AddDatapoints(ctx context.Context, points []*datapoint.Datapoint) (err error)

Sink is anything that can receive points collected by a Scheduler. This can be useful for stubbing out your collector to test the points that will be sent to SignalFx.

type TimeCounter Uses

type TimeCounter struct {
    NsBarrier int64
    Above     int64
    Below     int64

TimeCounter counts durations exactly above/below a value. NsBarrier is expected to be some amount of nanoseconds that the barrier exists at

func (*TimeCounter) Add Uses

func (t *TimeCounter) Add(dur time.Duration)

Add includes a datapoint in the source, incrementing above or below according to barrier

func (*TimeCounter) Collector Uses

func (t *TimeCounter) Collector(metric string) Collector

Collector returns a datapoint collector for this time counter that uses the given metric name.

type WithDimensions Uses

type WithDimensions struct {
    Dimensions map[string]string
    Collector  Collector

WithDimensions adds dimensions on top of the datapoints of a collector. This can be used to take an existing Collector and include extra dimensions.


sched := NewScheduler()
    Collector: GoMetricsSource,
    Dimensions: map[string]string{
        "extra": "dimension",

func (*WithDimensions) Datapoints Uses

func (w *WithDimensions) Datapoints() []*datapoint.Datapoint

Datapoints calls datapoints and adds on Dimensions



Package sfxclient imports 34 packages (graph) and is imported by 44 packages. Updated 2019-12-02. Refresh now. Tools for package owners.