prometheus/cmd/promtool/debug.go
Chih-Hung Yeh 912d19fb85 Add 3 commands in promtool for getting debug information from prometheus server (#4247)
`debug all` - all information
`debug metrics` - metrics  information
`debug pprof` - profiling  information

the final result is compressed in a `tar.gz` file

Signed-off-by: chyeh <chyeh.taiwan@gmail.com>
2018-07-18 10:52:01 +03:00

126 lines
2.9 KiB
Go

// Copyright 2015 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package main
import (
"bytes"
"fmt"
"net/http"
"os"
"github.com/google/pprof/profile"
)
type debugWriterConfig struct {
serverURL string
tarballName string
pathToFileName map[string]string
postProcess func(b []byte) ([]byte, error)
}
type debugWriter struct {
archiver
httpClient
requestToFile map[*http.Request]string
postProcess func(b []byte) ([]byte, error)
}
func newDebugWriter(cfg debugWriterConfig) (*debugWriter, error) {
client, err := newPrometheusHTTPClient(cfg.serverURL)
if err != nil {
return nil, err
}
archiver, err := newTarGzFileWriter(cfg.tarballName)
if err != nil {
return nil, err
}
reqs := make(map[*http.Request]string)
for path, filename := range cfg.pathToFileName {
req, err := http.NewRequest(http.MethodGet, client.urlJoin(path), nil)
if err != nil {
return nil, err
}
reqs[req] = filename
}
return &debugWriter{
archiver,
client,
reqs,
cfg.postProcess,
}, nil
}
func (w *debugWriter) Write() int {
for req, filename := range w.requestToFile {
_, body, err := w.do(req)
if err != nil {
fmt.Fprintln(os.Stderr, "error executing HTTP request:", err)
return 1
}
buf, err := w.postProcess(body)
if err != nil {
fmt.Fprintln(os.Stderr, "error post-processing HTTP response body:", err)
return 1
}
if err := w.archiver.write(filename, buf); err != nil {
fmt.Fprintln(os.Stderr, "error writing into archive:", err)
return 1
}
}
if err := w.close(); err != nil {
fmt.Fprintln(os.Stderr, "error closing archiver:", err)
return 1
}
fmt.Printf("Compiling debug information complete, all files written in %q.\n", w.filename())
return 0
}
func validate(b []byte) (*profile.Profile, error) {
p, err := profile.Parse(bytes.NewReader(b))
if err != nil {
return nil, err
}
return p, nil
}
var pprofPostProcess = func(b []byte) ([]byte, error) {
p, err := validate(b)
if err != nil {
return nil, err
}
var buf bytes.Buffer
if err := p.WriteUncompressed(&buf); err != nil {
return nil, err
}
fmt.Println(p.String())
return buf.Bytes(), nil
}
var metricsPostProcess = func(b []byte) ([]byte, error) {
fmt.Println(string(b))
return b, nil
}
var allPostProcess = func(b []byte) ([]byte, error) {
_, err := validate(b)
if err != nil {
return metricsPostProcess(b)
}
return pprofPostProcess(b)
}