Circonus metrics tracking for Go applications
This library supports named counters, gauges and histograms. It also provides convenience wrappers for registering latency instrumented functions with Go's builtin http server.
Initializing only requires setting an API Token at a minimum.
Options
See OPTIONS.md for information on all of the available cgm options.
Example
Bare bones minimum
A working cut-n-past example. Simply set the required environment variable CIRCONUS_API_TOKEN
and run.
package main
import (
"log"
"math/rand"
"os"
"os/signal"
"syscall"
"time"
cgm "github.com/circonus-labs/circonus-gometrics/v3"
)
func main() {
logger := log.New(os.Stdout, "", log.LstdFlags)
logger.Println("Configuring cgm")
cmc := &cgm.Config{}
cmc.Debug = false
cmc.Log = logger
cmc.CheckManager.API.TokenKey = os.Getenv("CIRCONUS_API_TOKEN")
logger.Println("Creating new cgm instance")
metrics, err := cgm.NewCirconusMetrics(cmc)
if err != nil {
logger.Println(err)
os.Exit(1)
}
src := rand.NewSource(time.Now().UnixNano())
rnd := rand.New(src)
logger.Println("Adding ctrl-c trap")
c := make(chan os.Signal, 2)
signal.Notify(c, os.Interrupt, syscall.SIGTERM)
go func() {
<-c
logger.Println("Received CTRL-C, flushing outstanding metrics before exit")
metrics.Flush()
os.Exit(0)
}()
logger.Println("Starting to send metrics")
max := 60
for i := 1; i < max; i++ {
logger.Printf("\tmetric set %d of %d", i, 60)
metrics.Timing("foo", rnd.Float64()*10)
metrics.Increment("bar")
metrics.Gauge("baz", 10)
time.Sleep(time.Second)
}
metrics.SetText("fini", "complete")
logger.Println("Flushing any outstanding metrics manually")
metrics.Flush()
}
A more complete example
A working, cut-n-paste example with all options available for modification. Also, demonstrates metric tagging.
package main
import (
"log"
"math/rand"
"os"
"os/signal"
"syscall"
"time"
cgm "github.com/circonus-labs/circonus-gometrics/v3"
)
func main() {
logger := log.New(os.Stdout, "", log.LstdFlags)
logger.Println("Configuring cgm")
cmc := &cgm.Config{}
cmc.Interval = "10s"
cmc.Log = logger
cmc.Debug = false
cmc.ResetCounters = "true"
cmc.ResetGauges = "true"
cmc.ResetHistograms = "true"
cmc.ResetText = "true"
cmc.CheckManager.API.TokenKey = os.Getenv("CIRCONUS_API_TOKEN")
cmc.CheckManager.API.TokenApp = os.Getenv("CIRCONUS_API_APP")
cmc.CheckManager.API.URL = os.Getenv("CIRCONUS_API_URL")
cmc.CheckManager.API.TLSConfig = nil
cmc.CheckManager.Check.SubmissionURL = os.Getenv("CIRCONUS_SUBMISSION_URL")
cmc.CheckManager.Check.ID = os.Getenv("CIRCONUS_CHECK_ID")
cmc.CheckManager.Check.InstanceID = ""
cmc.CheckManager.Check.DisplayName = ""
cmc.CheckManager.Check.TargetHost = ""
cmc.CheckManager.Check.SearchTag = ""
cmc.CheckManager.Check.Secret = ""
cmc.CheckManager.Check.Tags = ""
cmc.CheckManager.Check.MaxURLAge = "5m"
cmc.CheckManager.Check.ForceMetricActivation = "false"
cmc.CheckManager.Broker.ID = ""
cmc.CheckManager.Broker.SelectTag = ""
cmc.CheckManager.Broker.MaxResponseTime = "500ms"
cmc.CheckManager.Broker.TLSConfig = nil
logger.Println("Creating new cgm instance")
metrics, err := cgm.NewCirconusMetrics(cmc)
if err != nil {
logger.Println(err)
os.Exit(1)
}
src := rand.NewSource(time.Now().UnixNano())
rnd := rand.New(src)
logger.Println("Adding ctrl-c trap")
c := make(chan os.Signal, 2)
signal.Notify(c, os.Interrupt, syscall.SIGTERM)
go func() {
<-c
logger.Println("Received CTRL-C, flushing outstanding metrics before exit")
metrics.Flush()
os.Exit(0)
}()
metrics.AddMetricTags("foo", []string{"cgm:test"})
metrics.AddMetricTags("baz", []string{"cgm:test"})
logger.Println("Starting to send metrics")
max := 60
for i := 1; i < max; i++ {
logger.Printf("\tmetric set %d of %d", i, 60)
metrics.Timing("foo", rnd.Float64()*10)
metrics.Increment("bar")
metrics.Gauge("baz", 10)
if i == 35 {
metrics.SetMetricTags("baz", []string{"cgm:reset_test", "cgm:test2"})
}
time.Sleep(time.Second)
}
logger.Println("Flushing any outstanding metrics manually")
metrics.Flush()
}
HTTP Handler wrapping
http.HandleFunc("/", metrics.TrackHTTPLatency("/", handler_func))
HTTP latency example
package main
import (
"os"
"fmt"
"net/http"
cgm "github.com/circonus-labs/circonus-gometrics/v3"
)
func main() {
cmc := &cgm.Config{}
cmc.CheckManager.API.TokenKey = os.Getenv("CIRCONUS_API_TOKEN")
metrics, err := cgm.NewCirconusMetrics(cmc)
if err != nil {
panic(err)
}
http.HandleFunc("/", metrics.TrackHTTPLatency("/", func(w http.ResponseWriter, r *http.Request) {
fmt.Fprintf(w, "Hello, %s!", r.URL.Path[1:])
}))
http.ListenAndServe(":8080", http.DefaultServeMux)
}
Unless otherwise noted, the source files are distributed under the BSD-style license found in the LICENSE file.