all: remove legacy gomote API and SSH implementation

This removes the original API used to instantiate remote buildlet and
gomote instances. This also removes the original gomote SSH access
implementation. This API has been replaced with a GRPC based API. The
SSH functionality has been replaced with an implementation which uses
certificate authentication.

Gomote client changes will follow this CL once in-flight changes have been submitted.

Updates golang/go#47521
Fixes golang/go#54735

Change-Id: Idfd7b95eb7ed64637e74c3c0149e0bff7027f507
Reviewed-on: https://go-review.googlesource.com/c/build/+/430279
Run-TryBot: Carlos Amedee <carlos@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>

Author: cagedmantis

cmd/coordinator/coordinator.go

@@ -134,20 +134,6 @@ const (
 	maxStatusDone = 30
 )
 
-// httpRouter is the coordinator's handler, routing traffic to one of
-// two locations:
-//  1. a buildlet, from gomote clients (if X-Buildlet-Proxy is set)
-//  2. traffic to the coordinator itself (the default)
-func httpRouter(next http.Handler) http.Handler {
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		if r.Header.Get("X-Buildlet-Proxy") != "" {
-			requireBuildletProxyAuth(http.HandlerFunc(proxyBuildletHTTP)).ServeHTTP(w, r)
-			return
-		}
-		next.ServeHTTP(w, r)
-	})
-}
-
 var validHosts = map[string]bool{
 	"farmer.golang.org": true,
 	"build.golang.org":  true,
@@ -248,14 +234,8 @@ func main() {
 	// TODO(golang.org/issue/36841): remove after key functions are moved into
 	// a shared package.
 	pool.SetBuilderMasterKey(masterKey())
-
 	sp := remote.NewSessionPool(context.Background())
-	// TODO(go.dev/issue/54735): remove while legacy gomote implementation is being removed.
-	isRemoteBuildlet := func(instName string) bool {
-		return isGCERemoteBuildlet(instName) || sp.IsSession(instName)
-	}
-
-	err := pool.InitGCE(sc, &basePinErr, isRemoteBuildlet, *buildEnvName, *mode)
+	err := pool.InitGCE(sc, &basePinErr, sp.IsSession, *buildEnvName, *mode)
 	if err != nil {
 		if *mode == "" {
 			*mode = "dev"
@@ -283,7 +263,7 @@ func main() {
 	if *mode == "prod" || (*mode == "dev" && *devEnableEC2) {
 		// TODO(golang.org/issues/38337) the coordinator will use a package scoped pool
 		// until the coordinator is refactored to not require them.
-		ec2Pool := mustCreateEC2BuildletPool(sc, isRemoteBuildlet)
+		ec2Pool := mustCreateEC2BuildletPool(sc, sp.IsSession)
 		defer ec2Pool.Close()
 	}
 
@@ -384,8 +364,6 @@ func main() {
 	mux.HandleFunc("/status/post-submit-active.json", handlePostSubmitActiveJSON)
 	mux.Handle("/dashboard", dashV2)
 	mux.HandleFunc("/queues", handleQueues)
-	mux.Handle("/buildlet/create", requireBuildletProxyAuth(http.HandlerFunc(handleBuildletCreate)))
-	mux.Handle("/buildlet/list", requireBuildletProxyAuth(http.HandlerFunc(handleBuildletList)))
 	if *mode == "dev" {
 		// TODO(crawshaw): do more in dev mode
 		gce.BuildletPool().SetEnabled(*devEnableGCE)
@@ -410,7 +388,7 @@ func main() {
 		if err != nil {
 			return nil, fmt.Errorf("unable to retrieve keys for SSH Server: %v", err)
 		}
-		return remote.NewSSHServer(*sshAddr, privateKey, publicKey, sshCA, sp, remoteBuildlets)
+		return remote.NewSSHServer(*sshAddr, privateKey, publicKey, sshCA, sp)
 	}
 	sshServ, err := configureSSHServer()
 	if err != nil {
@@ -428,14 +406,7 @@ func main() {
 			}
 		}()
 	}
-
-	h := httpRouter(mux)
-	if *mode == "dev" {
-		// Use hostPathHandler in local development mode (only) to improve
-		// convenience of testing multiple domains that coordinator serves.
-		h = hostPathHandler(h)
-	}
-	log.Fatalln(https.ListenAndServe(context.Background(), h))
+	log.Fatalln(https.ListenAndServe(context.Background(), mux))
 }
 
 // ignoreAllNewWork, when true, prevents addWork from doing anything.