blob: c902387ae925adf0fb2adbd55c2ff76b2d947e06 [file] [log] [blame]
// Copyright 2019 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package debug exports debug information for gopls.
package debug
import (
type PrintMode int
const (
PlainText = PrintMode(iota)
// Version is a manually-updated mechanism for tracking versions.
const Version = "v0.9.5"
// ServerVersion is the format used by gopls to report its version to the
// client. This format is structured so that the client can parse it easily.
type ServerVersion struct {
Version string
type Module struct {
Replace *ModuleVersion `json:"replace,omitempty"`
type ModuleVersion struct {
Path string `json:"path,omitempty"`
Version string `json:"version,omitempty"`
Sum string `json:"sum,omitempty"`
// VersionInfo returns the build info for the gopls process. If it was not
// built in module mode, we return a GOPATH-specific message with the
// hardcoded version.
func VersionInfo() *ServerVersion {
if info, ok := readBuildInfo(); ok {
return getVersion(info)
buildInfo := &BuildInfo{}
// go1.17 or earlier, part of s.BuildInfo are embedded fields.
buildInfo.Path = "gopls, built in GOPATH mode"
buildInfo.GoVersion = runtime.Version()
return &ServerVersion{
Version: Version,
BuildInfo: buildInfo,
func getVersion(info *BuildInfo) *ServerVersion {
return &ServerVersion{
Version: Version,
BuildInfo: info,
// PrintServerInfo writes HTML debug info to w for the Instance.
func (i *Instance) PrintServerInfo(ctx context.Context, w io.Writer) {
section(w, HTML, "Server Instance", func() {
fmt.Fprintf(w, "Start time: %v\n", i.StartTime)
fmt.Fprintf(w, "LogFile: %s\n", i.Logfile)
fmt.Fprintf(w, "Working directory: %s\n", i.Workdir)
fmt.Fprintf(w, "Address: %s\n", i.ServerAddress)
fmt.Fprintf(w, "Debug address: %s\n", i.DebugAddress())
PrintVersionInfo(ctx, w, true, HTML)
section(w, HTML, "Command Line", func() {
fmt.Fprintf(w, "<a href=/debug/pprof/cmdline>cmdline</a>")
// PrintVersionInfo writes version information to w, using the output format
// specified by mode. verbose controls whether additional information is
// written, including section headers.
func PrintVersionInfo(_ context.Context, w io.Writer, verbose bool, mode PrintMode) error {
info := VersionInfo()
if mode == JSON {
return printVersionInfoJSON(w, info)
if !verbose {
printBuildInfo(w, info, false, mode)
return nil
section(w, mode, "Build info", func() {
printBuildInfo(w, info, true, mode)
return nil
func printVersionInfoJSON(w io.Writer, info *ServerVersion) error {
js, err := json.MarshalIndent(info, "", "\t")
if err != nil {
return err
_, err = fmt.Fprint(w, string(js))
return err
func section(w io.Writer, mode PrintMode, title string, body func()) {
switch mode {
case PlainText:
fmt.Fprintln(w, title)
fmt.Fprintln(w, strings.Repeat("-", len(title)))
case Markdown:
fmt.Fprintf(w, "#### %s\n\n```\n", title)
fmt.Fprintf(w, "```\n")
case HTML:
fmt.Fprintf(w, "<h3>%s</h3>\n<pre>\n", title)
fmt.Fprint(w, "</pre>\n")
func printBuildInfo(w io.Writer, info *ServerVersion, verbose bool, mode PrintMode) {
fmt.Fprintf(w, "%v %v\n", info.Path, Version)
printModuleInfo(w, info.Main, mode)
if !verbose {
for _, dep := range info.Deps {
printModuleInfo(w, *dep, mode)
fmt.Fprintf(w, "go: %v\n", info.GoVersion)
func printModuleInfo(w io.Writer, m debug.Module, _ PrintMode) {
fmt.Fprintf(w, " %s@%s", m.Path, m.Version)
if m.Sum != "" {
fmt.Fprintf(w, " %s", m.Sum)
if m.Replace != nil {
fmt.Fprintf(w, " => %v", m.Replace.Path)
fmt.Fprintf(w, "\n")
type field struct {
index []int
var fields []field
// find all the options. The presumption is that the Options are nested structs
// and that pointers don't need to be dereferenced
func swalk(t reflect.Type, ix []int, indent string) {
switch t.Kind() {
case reflect.Struct:
for i := 0; i < t.NumField(); i++ {
fld := t.Field(i)
ixx := append(append([]int{}, ix...), i)
swalk(fld.Type, ixx, indent+". ")
// everything is either a struct or a field (that's an assumption about Options)
fields = append(fields, field{ix})
type sessionOption struct {
Name string
Type string
Current string
Default string
func showOptions(o *source.Options) []sessionOption {
var out []sessionOption
t := reflect.TypeOf(*o)
swalk(t, []int{}, "")
v := reflect.ValueOf(*o)
do := reflect.ValueOf(*source.DefaultOptions())
for _, f := range fields {
val := v.FieldByIndex(f.index)
def := do.FieldByIndex(f.index)
tx := t.FieldByIndex(f.index)
is := strVal(val)
was := strVal(def)
out = append(out, sessionOption{
Name: tx.Name,
Type: tx.Type.String(),
Current: is,
Default: was,
sort.Slice(out, func(i, j int) bool {
rd := out[i].Current == out[i].Default
ld := out[j].Current == out[j].Default
if rd != ld {
return ld
return out[i].Name < out[j].Name
return out
func strVal(val reflect.Value) string {
switch val.Kind() {
case reflect.Bool:
return fmt.Sprintf("%v", val.Interface())
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
return fmt.Sprintf("%v", val.Interface())
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
return fmt.Sprintf("%v", val.Interface())
case reflect.Uintptr, reflect.UnsafePointer:
return fmt.Sprintf("0x%x", val.Pointer())
case reflect.Complex64, reflect.Complex128:
return fmt.Sprintf("%v", val.Complex())
case reflect.Array, reflect.Slice:
ans := []string{}
for i := 0; i < val.Len(); i++ {
ans = append(ans, strVal(val.Index(i)))
return fmt.Sprintf("%v", ans)
case reflect.Chan, reflect.Func, reflect.Ptr:
return val.Kind().String()
case reflect.Struct:
var x source.Analyzer
if val.Type() != reflect.TypeOf(x) {
return val.Kind().String()
// this is sort of ugly, but usable
str := val.FieldByName("Analyzer").Elem().FieldByName("Doc").String()
ix := strings.Index(str, "\n")
if ix == -1 {
ix = len(str)
return str[:ix]
case reflect.String:
return fmt.Sprintf("%q", val.Interface())
case reflect.Map:
ans := []string{}
iter := val.MapRange()
for iter.Next() {
k := iter.Key()
v := iter.Value()
ans = append(ans, fmt.Sprintf("%s:%s, ", strVal(k), strVal(v)))
return fmt.Sprintf("%v", ans)
return fmt.Sprintf("??%s??", val.Type())