//go:build ignore
package main
import (
"flag"
"fmt"
"math/rand"
"net/http"
"time"
_ "net/http/pprof"
"blitiri.com.ar/go/srv/nettrace"
)
func main() {
addr := flag.String("addr", ":8080", "listening address")
flag.Parse()
go RandomEvents("random-one")
go RandomEvents("random-two")
go RandomEvents("random-three")
go RandomLongEvent("random-long", "long-one")
go RandomLongEvent("random-long", "long-two")
go RandomLongEvent("random-long", "long-three")
go RandomBunny("random-bunny", "first 🐇")
go RandomNested("random-nested")
go RandomLazy("random-lazy")
http.DefaultServeMux.Handle("/",
WithLogging(http.HandlerFunc(HandleRoot)))
http.DefaultServeMux.Handle("/debug/traces",
WithLogging(http.HandlerFunc(nettrace.RenderTraces)))
fmt.Printf("listening on %s\n", *addr)
http.ListenAndServe(*addr, nil)
}
func RandomEvents(family string) {
for i := 0; ; i++ {
tr := nettrace.New(family, fmt.Sprintf("evt-%d", i))
randomTrace(family, tr)
}
}
func randomTrace(family string, tr nettrace.Trace) {
tr.Printf("this is a random event")
tr.Printf("and it has a random delay")
delay := time.Duration(rand.Intn(1000)) * time.Millisecond
tr.Printf("sleeping %v", delay)
time.Sleep(delay)
if rand.Intn(100) < 1 {
tr.Printf("this unlucky one is an error")
tr.SetError()
}
if rand.Intn(100) < 10 {
tr.Printf("this one got super verbose!")
for j := 0; j < 100; j++ {
tr.Printf("message %d", j)
}
}
if rand.Intn(100) < 30 {
tr.Printf("this one had a child")
c := tr.NewChild(family, "achild")
go randomTrace(family, c)
}
tr.Printf("all done")
tr.Finish()
}
func RandomLongEvent(family, title string) {
tr := nettrace.New(family, title)
tr.Printf("this is a random long event")
for i := 0; ; i++ {
delay := time.Duration(rand.Intn(100)) * time.Millisecond
time.Sleep(delay)
tr.Printf("message %d, slept %v", i, delay)
}
tr.Finish()
}
func RandomBunny(family, title string) {
tr := nettrace.New(family, title)
tr.SetMaxEvents(100)
tr.Printf("this is the top 🐇")
for i := 0; ; i++ {
delay := time.Duration(rand.Intn(100)) * time.Millisecond
time.Sleep(delay)
tr.Printf("message %d, slept %v", i, delay)
if rand.Intn(100) < 40 {
c := tr.NewChild(family, fmt.Sprintf("child-%d", i))
go randomTrace(family, c)
}
if rand.Intn(100) < 40 {
n := nettrace.New(family, fmt.Sprintf("linked-%d", i))
go randomTrace(family, n)
tr.Link(n, "linking with this guy")
}
}
tr.Finish()
}
func randomNested(family string, depth int, parent nettrace.Trace) {
tr := parent.NewChild(family, fmt.Sprintf("nested-%d", depth))
defer tr.Finish()
tr.Printf("I am a spoiled child")
delay := time.Duration(rand.Intn(100)) * time.Millisecond
time.Sleep(delay)
tr.Printf("slept %v", delay)
if depth > 10 {
tr.Printf("I went too far")
return
}
// If we make this < 50, then it grows forever.
if rand.Intn(100) < 75 {
tr.Printf("I sang really well")
return
}
max := rand.Intn(5)
for i := 0; i < max; i++ {
tr.Printf("spawning %d", i)
go randomNested(family, depth+1, tr)
}
}
func RandomNested(family string) {
tr := nettrace.New(family, "nested-0")
for i := 0; ; i++ {
randomNested(family, 1, tr)
}
}
func RandomLazy(family string) {
for i := 0; ; i++ {
tr := nettrace.New(family, fmt.Sprintf("evt-%d", i))
tr.Printf("I am very lazy and do little work")
tr.Finish()
time.Sleep(500 * time.Millisecond)
}
}
func HandleRoot(w http.ResponseWriter, r *http.Request) {
if delayS := r.FormValue("delay"); delayS != "" {
delay, err := time.ParseDuration(delayS)
if err != nil {
http.Error(w, err.Error(), http.StatusBadRequest)
return
}
time.Sleep(delay)
}
if withError := r.FormValue("error"); withError != "" {
tr, _ := nettrace.FromContext(r.Context())
tr.SetError()
}
w.Write([]byte(rootHTML))
}
func WithLogging(parent http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
tr := nettrace.New("http", r.URL.String())
defer tr.Finish()
// Associate the trace with this request.
r = r.WithContext(nettrace.NewContext(r.Context(), tr))
tr.Printf("%s %s %s %s",
r.RemoteAddr, r.Proto, r.Method, r.URL.String())
start := time.Now()
parent.ServeHTTP(w, r)
latency := time.Since(start)
tr.Printf("handler took %s", latency)
// 1.2.3.4:34575 HTTP/2.0 GET /path = 1.2ms
fmt.Printf("%s %s %s %s = %s\n",
r.RemoteAddr, r.Proto, r.Method, r.URL.String(),
latency)
})
}
const rootHTML = `
Traces
`