Remove old d3 flamegraph code and d3 dependency. (#825)

Fixes #777.

internal/driver/html/common.js

@@ -678,7 +678,7 @@ function viewer(baseUrl, nodes, options) {
   }
 
   const ids = ['topbtn', 'graphbtn',
-               'flamegraph', 'flamegraph2', 'flamegraphold',
+               'flamegraph',
                'peek', 'list',
                'disasm', 'focus', 'ignore', 'hide', 'show', 'show-from'];
   ids.forEach(makeSearchLinkDynamic);

internal/driver/html/header.html

@@ -12,7 +12,6 @@ <h1><a href="./">pprof</a></h1>
       <a title="{{.Help.top}}"  href="./top" id="topbtn">Top</a>
       <a title="{{.Help.graph}}" href="./" id="graphbtn">Graph</a>
       <a title="{{.Help.flamegraph}}" href="./flamegraph" id="flamegraph">Flame Graph</a>
-      <a title="{{.Help.flamegraphold}}" href="./flamegraphold" id="flamegraphold">Flame Graph (old)</a>
       <a title="{{.Help.peek}}" href="./peek" id="peek">Peek</a>
       <a title="{{.Help.list}}" href="./source" id="list">Source</a>
       <a title="{{.Help.disasm}}" href="./disasm" id="disasm">Disassemble</a>

internal/driver/stacks.go

@@ -22,7 +22,7 @@ import (
 	"github.com/google/pprof/internal/report"
 )
 
-// stackView generates the new flamegraph view.
+// stackView generates the flamegraph view.
 func (ui *webInterface) stackView(w http.ResponseWriter, req *http.Request) {
 	// Get all data in a report.
 	rpt, errList := ui.makeReport(w, req, []string{"svg"}, func(cfg *config) {

internal/driver/webhtml.go

@@ -19,8 +19,6 @@ import (
 	"fmt"
 	"html/template"
 	"os"
-
-	"github.com/google/pprof/third_party/d3flamegraph"
 )
 
 //go:embed html
@@ -52,10 +50,6 @@ func addTemplates(templates *template.Template) {
 		template.Must(templates.AddParseTree(name, sub.Tree))
 	}
 
-	// Pre-packaged third-party files.
-	def("d3flamegraphscript", d3flamegraph.JSSource)
-	def("d3flamegraphcss", d3flamegraph.CSSSource)
-
 	// Embedded files.
 	def("css", loadCSS("html/common.css"))
 	def("header", loadFile("html/header.html"))
@@ -64,7 +58,7 @@ func addTemplates(templates *template.Template) {
 	def("top", loadFile("html/top.html"))
 	def("sourcelisting", loadFile("html/source.html"))
 	def("plaintext", loadFile("html/plaintext.html"))
-	def("flamegraph", loadFile("html/flamegraph.html"))
+	// TODO: Rename "stacks" to "flamegraph" to seal moving off d3 flamegraph.
 	def("stacks", loadFile("html/stacks.html"))
 	def("stacks_css", loadCSS("html/stacks.css"))
 	def("stacks_js", loadJS("html/stacks.js"))

internal/driver/webui.go

@@ -112,7 +112,6 @@ func serveWebInterface(hostport string, p *profile.Profile, o *plugin.Options, d
 	ui.help["details"] = "Show information about the profile and this view"
 	ui.help["graph"] = "Display profile as a directed graph"
 	ui.help["flamegraph"] = "Display profile as a flame graph"
-	ui.help["flamegraphold"] = "Display profile as a flame graph (old version; slated for removal)"
 	ui.help["reset"] = "Show the entire profile"
 	ui.help["save_config"] = "Save current settings"
 
@@ -130,9 +129,9 @@ func serveWebInterface(hostport string, p *profile.Profile, o *plugin.Options, d
 			"/disasm":        http.HandlerFunc(ui.disasm),
 			"/source":        http.HandlerFunc(ui.source),
 			"/peek":          http.HandlerFunc(ui.peek),
-			"/flamegraphold": http.HandlerFunc(ui.flamegraph),
 			"/flamegraph":    http.HandlerFunc(ui.stackView),
-			"/flamegraph2":   http.HandlerFunc(ui.stackView), // Support older URL
+			"/flamegraph2":   redirectWithQuery("flamegraph", http.StatusMovedPermanently), // Keep legacy URL working.
+			"/flamegraphold": redirectWithQuery("flamegraph", http.StatusMovedPermanently), // Keep legacy URL working.
 			"/saveconfig":    http.HandlerFunc(ui.saveConfig),
 			"/deleteconfig":  http.HandlerFunc(ui.deleteConfig),
 			"/download": http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
@@ -209,15 +208,20 @@ func defaultWebServer(args *plugin.HTTPServerArgs) error {
 	// https://github.com/google/pprof/pull/348
 	mux := http.NewServeMux()
 	mux.Handle("/ui/", http.StripPrefix("/ui", handler))
-	mux.Handle("/", redirectWithQuery("/ui"))
+	mux.Handle("/", redirectWithQuery("/ui", http.StatusTemporaryRedirect))
 	s := &http.Server{Handler: mux}
 	return s.Serve(ln)
 }
 
-func redirectWithQuery(path string) http.HandlerFunc {
+// redirectWithQuery responds with a given redirect code, preserving query
+// parameters in the redirect URL. It does not convert relative paths to
+// absolute paths like http.Redirect does, so that HTTPServerArgs.Handlers can
+// generate relative redirects that work with the external prefixing.
+func redirectWithQuery(path string, code int) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		pathWithQuery := &gourl.URL{Path: path, RawQuery: r.URL.RawQuery}
-		http.Redirect(w, r, pathWithQuery.String(), http.StatusTemporaryRedirect)
+		w.Header().Set("Location", pathWithQuery.String())
+		w.WriteHeader(code)
 	}
 }
 

internal/driver/webui_test.go

@@ -91,16 +91,6 @@ func TestWebInterface(t *testing.T) {
 			[]string{"300ms.*F1", "200ms.*300ms.*F2"}, false},
 		{"/disasm?f=" + url.QueryEscape("F[12]"),
 			[]string{"f1:asm", "f2:asm"}, false},
-		{"/flamegraphold", []string{
-			"File: testbin",
-			// Check profile frame JSON is included.
-			`\\u0022n\\u0022:\\u0022root\\u0022`,
-			`\\u0022n\\u0022:\\u0022F1\\u0022`,
-			// Check d3-flame-graph JS is included.
-			`flamegraph:\(\)=>|flamegraph.*function|function.*flamegraph`,
-			// Check d3-flame-graph CSS is included.
-			".d3-flame-graph rect {",
-		}, false},
 		{"/flamegraph", []string{
 			"File: testbin",
 			// Check that interesting frames are included.
@@ -313,7 +303,7 @@ func TestIsLocalHost(t *testing.T) {
 }
 
 func BenchmarkTop(b *testing.B)   { benchmarkURL(b, "/top", false) }
-func BenchmarkFlame(b *testing.B) { benchmarkURL(b, "/flamegraph2", false) }
+func BenchmarkFlame(b *testing.B) { benchmarkURL(b, "/flamegraph", false) }
 func BenchmarkDot(b *testing.B)   { benchmarkURL(b, "/", true) }
 
 func benchmarkURL(b *testing.B, path string, needDot bool) {