The profiler package implements profiling features and a web frontend for easy access during runtime. It is based on the Go-inherent net/http/pprof package, but extends it by some additional features. Unlike net/http/pprof, the profiler package usage is not implicit by mere inclusion for the sake of its side effects, but explicit, i.e. an instance of a Profiler type has to be created, thus allowing better control over its parameters. Further differences w.r.t. net/http/pprof are:
- The web frontend is always run using a dedicated HTTP server instance to avoid interference with any web server potentially served by the calling package (including accidental exposure of the debugging interface on a public web server)
- Several functional options are available, allowing to set various parameters in an easy and efficient manner (e.g. a custom HTTP server or even any custom / additional middleware)
- Direct access to plain text CPU profiles during runtime (i.e. without the need to download a binary profile and the use of e.g. go tool pprof ...)
- Slightly improved web interface
The import path for the package is github.com/fako1024/profiler.
To install it, run:
go get github.com/fako1024/profiler
The most trivial use case is to import the package and start up the profiler with default options in the background:
...
import "github.com/fako1024/profiler"
func main() {
// Makes profiler available on http://127.0.0.1:6060/
profiler.New().Run()
...
}More granular control is possible via functional option calls (all available options can be found in options.go):
...
import "github.com/fako1024/profiler"
// Custom template, only displaying the basic profiles
const customTemplate = `<html>
<head>
<title>Go Custom Profiling interface</title>
</head>
<body>
<b>Go Custom Profiling interface</b><br>
<br>
<table>
{{range .}}
<tr><td align=left><a href="{{.Name}}?debug=1">{{.Name}}</a><td> ({{.Count}})
{{end}}
</table>
</body>
</html>
`
// Custom middleware, logging all request URLs to STDOUT
func customMiddleware(next http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
// Print the request URL
fmt.Println(r.URL.String())
// Serve the next layer(s) of middleware
next.ServeHTTP(w, r)
})
}
func main() {
profiler.New(
profiler.WithAddr("127.0.0.1:6061"), // Start web interface on port 6061
profiler.WithKeyPair("/tmp/tls.crt", "/tmp/tls.key"), // Enable HTTPS (certificate / key)
profiler.WithMiddleware(customMiddleware), // Enable request logging to STDOUT
profiler.WithHTMLTemplate(customTemplate), // Set custom HTML index page template
profiler.WithErrorHandler(func(err error) { // Set error handler (panic in case http.ListenAndServe() fails)
panic(err)
}),
).Run()
...
}The profiler package is governed under a BSD-style license. Please see the LICENSE file for details.