blob: 89bc5586683a6fed947bf008b56e60c4ca910f19 [file] [log] [blame]
// Copyright 2017 Google Inc. All Rights Reserved.
//
// 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 driver
import (
"bytes"
"fmt"
"html/template"
"net"
"net/http"
gourl "net/url"
"os"
"os/exec"
"strconv"
"strings"
"time"
"github.com/google/pprof/internal/graph"
"github.com/google/pprof/internal/plugin"
"github.com/google/pprof/internal/report"
"github.com/google/pprof/profile"
)
// webInterface holds the state needed for serving a browser based interface.
type webInterface struct {
prof *profile.Profile
options *plugin.Options
help map[string]string
templates *template.Template
}
func makeWebInterface(p *profile.Profile, opt *plugin.Options) *webInterface {
templates := template.New("templategroup")
addTemplates(templates)
report.AddSourceTemplates(templates)
return &webInterface{
prof: p,
options: opt,
help: make(map[string]string),
templates: templates,
}
}
// maxEntries is the maximum number of entries to print for text interfaces.
const maxEntries = 50
// errorCatcher is a UI that captures errors for reporting to the browser.
type errorCatcher struct {
plugin.UI
errors []string
}
func (ec *errorCatcher) PrintErr(args ...interface{}) {
ec.errors = append(ec.errors, strings.TrimSuffix(fmt.Sprintln(args...), "\n"))
ec.UI.PrintErr(args...)
}
// webArgs contains arguments passed to templates in webhtml.go.
type webArgs struct {
Title string
Errors []string
Total int64
Legend []string
Help map[string]string
Nodes []string
HTMLBody template.HTML
TextBody string
Top []report.TextItem
FlameGraph template.JS
}
func serveWebInterface(hostport string, p *profile.Profile, o *plugin.Options) error {
host, port, err := getHostAndPort(hostport)
if err != nil {
return err
}
interactiveMode = true
ui := makeWebInterface(p, o)
for n, c := range pprofCommands {
ui.help[n] = c.description
}
for n, v := range pprofVariables {
ui.help[n] = v.help
}
ui.help["details"] = "Show information about the profile and this view"
ui.help["graph"] = "Display profile as a directed graph"
ui.help["reset"] = "Show the entire profile"
server := o.HTTPServer
if server == nil {
server = defaultWebServer
}
args := &plugin.HTTPServerArgs{
Hostport: net.JoinHostPort(host, strconv.Itoa(port)),
Host: host,
Port: port,
Handlers: map[string]http.Handler{
"/": http.HandlerFunc(ui.dot),
"/top": http.HandlerFunc(ui.top),
"/disasm": http.HandlerFunc(ui.disasm),
"/source": http.HandlerFunc(ui.source),
"/peek": http.HandlerFunc(ui.peek),
"/flamegraph": http.HandlerFunc(ui.flamegraph),
},
}
if o.UI.WantBrowser() {
go openBrowser("http://"+args.Hostport, o)
}
return server(args)
}
func getHostAndPort(hostport string) (string, int, error) {
host, portStr, err := net.SplitHostPort(hostport)
if err != nil {
return "", 0, fmt.Errorf("could not split http address: %v", err)
}
if host == "" {
host = "localhost"
}
var port int
if portStr == "" {
ln, err := net.Listen("tcp", net.JoinHostPort(host, "0"))
if err != nil {
return "", 0, fmt.Errorf("could not generate random port: %v", err)
}
port = ln.Addr().(*net.TCPAddr).Port
err = ln.Close()
if err != nil {
return "", 0, fmt.Errorf("could not generate random port: %v", err)
}
} else {
port, err = strconv.Atoi(portStr)
if err != nil {
return "", 0, fmt.Errorf("invalid port number: %v", err)
}
}
return host, port, nil
}
func defaultWebServer(args *plugin.HTTPServerArgs) error {
ln, err := net.Listen("tcp", args.Hostport)
if err != nil {
return err
}
isLocal := isLocalhost(args.Host)
handler := http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
if isLocal {
// Only allow local clients
host, _, err := net.SplitHostPort(req.RemoteAddr)
if err != nil || !isLocalhost(host) {
http.Error(w, "permission denied", http.StatusForbidden)
return
}
}
h := args.Handlers[req.URL.Path]
if h == nil {
// Fall back to default behavior
h = http.DefaultServeMux
}
h.ServeHTTP(w, req)
})
// We serve the ui at /ui/ and redirect there from the root. This is done
// to surface any problems with serving the ui at a non-root early. See:
//
// https://github.com/google/pprof/pull/348
mux := http.NewServeMux()
mux.Handle("/ui/", http.StripPrefix("/ui", handler))
mux.Handle("/", http.RedirectHandler("/ui/", http.StatusTemporaryRedirect))
s := &http.Server{Handler: mux}
return s.Serve(ln)
}
func isLocalhost(host string) bool {
for _, v := range []string{"localhost", "127.0.0.1", "[::1]", "::1"} {
if host == v {
return true
}
}
return false
}
func openBrowser(url string, o *plugin.Options) {
// Construct URL.
u, _ := gourl.Parse(url)
q := u.Query()
for _, p := range []struct{ param, key string }{
{"f", "focus"},
{"s", "show"},
{"i", "ignore"},
{"h", "hide"},
} {
if v := pprofVariables[p.key].value; v != "" {
q.Set(p.param, v)
}
}
u.RawQuery = q.Encode()
// Give server a little time to get ready.
time.Sleep(time.Millisecond * 500)
for _, b := range browsers() {
args := strings.Split(b, " ")
if len(args) == 0 {
continue
}
viewer := exec.Command(args[0], append(args[1:], u.String())...)
viewer.Stderr = os.Stderr
if err := viewer.Start(); err == nil {
return
}
}
// No visualizer succeeded, so just print URL.
o.UI.PrintErr(u.String())
}
func varsFromURL(u *gourl.URL) variables {
vars := pprofVariables.makeCopy()
vars["focus"].value = u.Query().Get("f")
vars["show"].value = u.Query().Get("s")
vars["ignore"].value = u.Query().Get("i")
vars["hide"].value = u.Query().Get("h")
return vars
}
// makeReport generates a report for the specified command.
func (ui *webInterface) makeReport(w http.ResponseWriter, req *http.Request,
cmd []string, vars ...string) (*report.Report, []string) {
v := varsFromURL(req.URL)
for i := 0; i+1 < len(vars); i += 2 {
v[vars[i]].value = vars[i+1]
}
catcher := &errorCatcher{UI: ui.options.UI}
options := *ui.options
options.UI = catcher
_, rpt, err := generateRawReport(ui.prof, cmd, v, &options)
if err != nil {
http.Error(w, err.Error(), http.StatusBadRequest)
ui.options.UI.PrintErr(err)
return nil, nil
}
return rpt, catcher.errors
}
// render generates html using the named template based on the contents of data.
func (ui *webInterface) render(w http.ResponseWriter, tmpl string,
rpt *report.Report, errList, legend []string, data webArgs) {
file := getFromLegend(legend, "File: ", "unknown")
profile := getFromLegend(legend, "Type: ", "unknown")
data.Title = file + " " + profile
data.Errors = errList
data.Total = rpt.Total()
data.Legend = legend
data.Help = ui.help
html := &bytes.Buffer{}
if err := ui.templates.ExecuteTemplate(html, tmpl, data); err != nil {
http.Error(w, "internal template error", http.StatusInternalServerError)
ui.options.UI.PrintErr(err)
return
}
w.Header().Set("Content-Type", "text/html")
w.Write(html.Bytes())
}
// dot generates a web page containing an svg diagram.
func (ui *webInterface) dot(w http.ResponseWriter, req *http.Request) {
rpt, errList := ui.makeReport(w, req, []string{"svg"})
if rpt == nil {
return // error already reported
}
// Generate dot graph.
g, config := report.GetDOT(rpt)
legend := config.Labels
config.Labels = nil
dot := &bytes.Buffer{}
graph.ComposeDot(dot, g, &graph.DotAttributes{}, config)
// Convert to svg.
svg, err := dotToSvg(dot.Bytes())
if err != nil {
http.Error(w, "Could not execute dot; may need to install graphviz.",
http.StatusNotImplemented)
ui.options.UI.PrintErr("Failed to execute dot. Is Graphviz installed?\n", err)
return
}
// Get all node names into an array.
nodes := []string{""} // dot starts with node numbered 1
for _, n := range g.Nodes {
nodes = append(nodes, n.Info.Name)
}
ui.render(w, "graph", rpt, errList, legend, webArgs{
HTMLBody: template.HTML(string(svg)),
Nodes: nodes,
})
}
func dotToSvg(dot []byte) ([]byte, error) {
cmd := exec.Command("dot", "-Tsvg")
out := &bytes.Buffer{}
cmd.Stdin, cmd.Stdout, cmd.Stderr = bytes.NewBuffer(dot), out, os.Stderr
if err := cmd.Run(); err != nil {
return nil, err
}
// Fix dot bug related to unquoted amperands.
svg := bytes.Replace(out.Bytes(), []byte("&;"), []byte("&amp;;"), -1)
// Cleanup for embedding by dropping stuff before the <svg> start.
if pos := bytes.Index(svg, []byte("<svg")); pos >= 0 {
svg = svg[pos:]
}
return svg, nil
}
func (ui *webInterface) top(w http.ResponseWriter, req *http.Request) {
rpt, errList := ui.makeReport(w, req, []string{"top"}, "nodecount", "500")
if rpt == nil {
return // error already reported
}
top, legend := report.TextItems(rpt)
var nodes []string
for _, item := range top {
nodes = append(nodes, item.Name)
}
ui.render(w, "top", rpt, errList, legend, webArgs{
Top: top,
Nodes: nodes,
})
}
// disasm generates a web page containing disassembly.
func (ui *webInterface) disasm(w http.ResponseWriter, req *http.Request) {
args := []string{"disasm", req.URL.Query().Get("f")}
rpt, errList := ui.makeReport(w, req, args)
if rpt == nil {
return // error already reported
}
out := &bytes.Buffer{}
if err := report.PrintAssembly(out, rpt, ui.options.Obj, maxEntries); err != nil {
http.Error(w, err.Error(), http.StatusBadRequest)
ui.options.UI.PrintErr(err)
return
}
legend := report.ProfileLabels(rpt)
ui.render(w, "plaintext", rpt, errList, legend, webArgs{
TextBody: out.String(),
})
}
// source generates a web page containing source code annotated with profile
// data.
func (ui *webInterface) source(w http.ResponseWriter, req *http.Request) {
args := []string{"weblist", req.URL.Query().Get("f")}
rpt, errList := ui.makeReport(w, req, args)
if rpt == nil {
return // error already reported
}
// Generate source listing.
var body bytes.Buffer
if err := report.PrintWebList(&body, rpt, ui.options.Obj, maxEntries); err != nil {
http.Error(w, err.Error(), http.StatusBadRequest)
ui.options.UI.PrintErr(err)
return
}
legend := report.ProfileLabels(rpt)
ui.render(w, "sourcelisting", rpt, errList, legend, webArgs{
HTMLBody: template.HTML(body.String()),
})
}
// peek generates a web page listing callers/callers.
func (ui *webInterface) peek(w http.ResponseWriter, req *http.Request) {
args := []string{"peek", req.URL.Query().Get("f")}
rpt, errList := ui.makeReport(w, req, args, "lines", "t")
if rpt == nil {
return // error already reported
}
out := &bytes.Buffer{}
if err := report.Generate(out, rpt, ui.options.Obj); err != nil {
http.Error(w, err.Error(), http.StatusBadRequest)
ui.options.UI.PrintErr(err)
return
}
legend := report.ProfileLabels(rpt)
ui.render(w, "plaintext", rpt, errList, legend, webArgs{
TextBody: out.String(),
})
}
// getFromLegend returns the suffix of an entry in legend that starts
// with param. It returns def if no such entry is found.
func getFromLegend(legend []string, param, def string) string {
for _, s := range legend {
if strings.HasPrefix(s, param) {
return s[len(param):]
}
}
return def
}