server: Split code for debug and version endpoints

server/etcdserver/api/etcdhttp/basic.go

@@ -1,4 +1,4 @@
-// Copyright 2015 The etcd Authors
+// Copyright 2022 The etcd Authors
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -15,75 +15,17 @@
 package etcdhttp
 
 import (
-	"encoding/json"
-	"expvar"
-	"fmt"
 	"net/http"
 
-	"go.etcd.io/etcd/api/v3/version"
 	"go.etcd.io/etcd/server/v3/etcdserver"
-	"go.etcd.io/etcd/server/v3/etcdserver/api"
+	httptypes "go.etcd.io/etcd/server/v3/etcdserver/api/etcdhttp/types"
-	"go.etcd.io/etcd/server/v3/etcdserver/api/etcdhttp/types"
 	"go.etcd.io/etcd/server/v3/etcdserver/api/v2error"
 	"go.uber.org/zap"
 )
 
-const (
+func HandleBasic(lg *zap.Logger, mux *http.ServeMux, peer etcdserver.ServerPeer) {
-	varsPath    = "/debug/vars"
+	HandleDebug(mux)
-	versionPath = "/version"
+	HandleVersion(mux, peer)
-)
-
-// HandleBasic adds handlers to a mux for serving JSON etcd client requests
-// that do not access the v2 store.
-func HandleBasic(lg *zap.Logger, mux *http.ServeMux, server etcdserver.ServerPeer) {
-	mux.HandleFunc(varsPath, serveVars)
-	mux.HandleFunc(versionPath, versionHandler(server.Cluster(), serveVersion))
-}
-
-func versionHandler(c api.Cluster, fn func(http.ResponseWriter, *http.Request, string)) http.HandlerFunc {
-	return func(w http.ResponseWriter, r *http.Request) {
-		v := c.Version()
-		if v != nil {
-			fn(w, r, v.String())
-		} else {
-			fn(w, r, "not_decided")
-		}
-	}
-}
-
-func serveVersion(w http.ResponseWriter, r *http.Request, clusterV string) {
-	if !allowMethod(w, r, "GET") {
-		return
-	}
-	vs := version.Versions{
-		Server:  version.Version,
-		Cluster: clusterV,
-	}
-
-	w.Header().Set("Content-Type", "application/json")
-	b, err := json.Marshal(&vs)
-	if err != nil {
-		panic(fmt.Sprintf("cannot marshal versions to json (%v)", err))
-	}
-	w.Write(b)
-}
-
-func serveVars(w http.ResponseWriter, r *http.Request) {
-	if !allowMethod(w, r, "GET") {
-		return
-	}
-
-	w.Header().Set("Content-Type", "application/json; charset=utf-8")
-	fmt.Fprintf(w, "{\n")
-	first := true
-	expvar.Do(func(kv expvar.KeyValue) {
-		if !first {
-			fmt.Fprintf(w, ",\n")
-		}
-		first = false
-		fmt.Fprintf(w, "%q: %s", kv.Key, kv.Value)
-	})
-	fmt.Fprintf(w, "\n}\n")
 }
 
 func allowMethod(w http.ResponseWriter, r *http.Request, m string) bool {
@@ -95,10 +37,10 @@ func allowMethod(w http.ResponseWriter, r *http.Request, m string) bool {
 	return false
 }
 
-// WriteError logs and writes the given Error to the ResponseWriter
+// writeError logs and writes the given Error to the ResponseWriter
 // If Error is an etcdErr, it is rendered to the ResponseWriter
 // Otherwise, it is assumed to be a StatusInternalServerError
-func WriteError(lg *zap.Logger, w http.ResponseWriter, r *http.Request, err error) {
+func writeError(lg *zap.Logger, w http.ResponseWriter, r *http.Request, err error) {
 	if err == nil {
 		return
 	}

server/etcdserver/api/etcdhttp/debug.go

@@ -0,0 +1,47 @@
+// Copyright 2015 The etcd 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 etcdhttp
+
+import (
+	"expvar"
+	"fmt"
+	"net/http"
+)
+
+const (
+	varsPath = "/debug/vars"
+)
+
+func HandleDebug(mux *http.ServeMux) {
+	mux.HandleFunc(varsPath, serveVars)
+}
+
+func serveVars(w http.ResponseWriter, r *http.Request) {
+	if !allowMethod(w, r, "GET") {
+		return
+	}
+
+	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	fmt.Fprintf(w, "{\n")
+	first := true
+	expvar.Do(func(kv expvar.KeyValue) {
+		if !first {
+			fmt.Fprintf(w, ",\n")
+		}
+		first = false
+		fmt.Fprintf(w, "%q: %s", kv.Key, kv.Value)
+	})
+	fmt.Fprintf(w, "\n}\n")
+}

server/etcdserver/api/etcdhttp/peer.go

@@ -145,7 +145,7 @@ func (h *peerMemberPromoteHandler) ServeHTTP(w http.ResponseWriter, r *http.Requ
 		case etcdserver.ErrLearnerNotReady:
 			http.Error(w, err.Error(), http.StatusPreconditionFailed)
 		default:
-			WriteError(h.lg, w, r, err)
+			writeError(h.lg, w, r, err)
 		}
 		h.lg.Warn(
 			"failed to promote a member",

server/etcdserver/api/etcdhttp/version.go

@@ -0,0 +1,61 @@
+// Copyright 2015 The etcd 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 etcdhttp
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+
+	"go.etcd.io/etcd/api/v3/version"
+	"go.etcd.io/etcd/server/v3/etcdserver"
+	"go.etcd.io/etcd/server/v3/etcdserver/api"
+)
+
+const (
+	versionPath = "/version"
+)
+
+func HandleVersion(mux *http.ServeMux, server etcdserver.ServerPeer) {
+	mux.HandleFunc(versionPath, versionHandler(server.Cluster(), serveVersion))
+}
+
+func versionHandler(c api.Cluster, fn func(http.ResponseWriter, *http.Request, string)) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		v := c.Version()
+		if v != nil {
+			fn(w, r, v.String())
+		} else {
+			fn(w, r, "not_decided")
+		}
+	}
+}
+
+func serveVersion(w http.ResponseWriter, r *http.Request, clusterV string) {
+	if !allowMethod(w, r, "GET") {
+		return
+	}
+	vs := version.Versions{
+		Server:  version.Version,
+		Cluster: clusterV,
+	}
+
+	w.Header().Set("Content-Type", "application/json")
+	b, err := json.Marshal(&vs)
+	if err != nil {
+		panic(fmt.Sprintf("cannot marshal versions to json (%v)", err))
+	}
+	w.Write(b)
+}