Support PD with Dashboard

.gitignore

@@ -13,3 +13,4 @@ default*
 .vscode/
 bindata.go
 /pkg/ui/pd-web/*
+/.cache

Makefile

@@ -54,6 +54,10 @@ pd-server: export GO111MODULE=on
 ifeq ("$(WITH_RACE)", "1")
 pd-server:
 	CGO_ENABLED=1 go build -race -gcflags '$(GCFLAGS)' -ldflags '$(LDFLAGS)' -o bin/pd-server cmd/pd-server/main.go
+else ifeq ("$(WITH_DASHBOARD)", "1")
+pd-server:
+	@./scripts/embed-dashboard-ui.sh
+	CGO_ENABLED=0 go build -gcflags '$(GCFLAGS)' -ldflags '$(LDFLAGS)' -tags dashboard_ui -o bin/pd-server cmd/pd-server/main.go
 else ifeq ("$(PD_WEB)", "1")
 pd-server: retool-setup
 	@./scripts/build-ui.sh
@@ -104,7 +108,7 @@ check-all: static lint tidy
 	@echo "checking"
 
 retool-setup: export GO111MODULE=off
-retool-setup: 
+retool-setup:
 	@which retool >/dev/null 2>&1 || go get github.com/twitchtv/retool
 	@./scripts/retool sync
 

README.md

@@ -14,6 +14,15 @@ PD supports distribution and fault-tolerance by embedding [etcd](https://github.
 1. Make sure [​*Go*​](https://golang.org/) (version 1.13) is installed.
 2. Use `make` to install PD. PD is installed in the `bin` directory.
 
+### Build with [TiDB Dashboard](https://github.com/pingcap-incubator/tidb-dashboard)
+
+```sh
+WITH_DASHBOARD=1 make pd-server
+# Start PD: bin/pd-server
+```
+
+Dashboard UI is available at http://127.0.0.1:2379/dashboard by default.
+
 ## Usage
 
 ### Command flags

go.mod

@@ -19,8 +19,7 @@ require (
 	github.com/golang/protobuf v1.3.2
 	github.com/golang/snappy v0.0.0-20180518054509-2e65f85255db // indirect
 	github.com/google/btree v1.0.0
-	github.com/gorilla/context v0.0.0-20160226214623-1ea25387ff6f // indirect
-	github.com/gorilla/mux v1.6.1
+	github.com/gorilla/mux v1.7.3
 	github.com/gorilla/websocket v1.2.0 // indirect
 	github.com/grpc-ecosystem/go-grpc-prometheus v1.2.0
 	github.com/juju/ratelimit v1.0.1
@@ -29,6 +28,7 @@ require (
 	github.com/onsi/gomega v1.4.2 // indirect
 	github.com/opentracing/opentracing-go v1.0.2
 	github.com/phf/go-queue v0.0.0-20170504031614-9abe38d0371d
+	github.com/pingcap-incubator/tidb-dashboard v0.0.0-20200108014525-06bfab74f3b7
 	github.com/pingcap/check v0.0.0-20191107115940-caf2b9e6ccf4
 	github.com/pingcap/errcode v0.0.0-20180921232412-a1a7271709d9
 	github.com/pingcap/failpoint v0.0.0-20191029060244-12f4ac2fd11d
@@ -47,6 +47,7 @@ require (
 	go.etcd.io/etcd v0.5.0-alpha.5.0.20191023171146-3cf2f69b5738
 	go.uber.org/goleak v0.10.0
 	go.uber.org/zap v1.12.0
+	golang.org/x/sys v0.0.0-20200107162124-548cf772de50 // indirect
 	google.golang.org/grpc v1.25.1
 	gopkg.in/natefinch/lumberjack.v2 v2.0.0
 )

pkg/dashboard/uiserver/.gitignore

@@ -0,0 +1 @@
+/embedded_assets_handler.go

pkg/dashboard/uiserver/empty_assets_handler.go

@@ -0,0 +1,23 @@
+// Copyright 2020 PingCAP, Inc.
+//
+// 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,
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// +build !dashboard_ui
+
+package uiserver
+
+import (
+	assetfs "github.com/elazarl/go-bindata-assetfs"
+)
+
+func assetFS() *assetfs.AssetFS {
+	return nil
+}

pkg/dashboard/uiserver/uiserver.go

@@ -0,0 +1,32 @@
+// Copyright 2020 PingCAP, Inc.
+//
+// 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,
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package uiserver
+
+import (
+	"io"
+	"net/http"
+)
+
+// Handler returns an http.Handler that serves the dashboard UI.
+func Handler() http.Handler {
+	fs := assetFS()
+	if fs != nil {
+		fileServer := http.FileServer(fs)
+		return fileServer
+	}
+
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		_, _ = io.WriteString(w, "Dashboard UI is not built.\n")
+	})
+}

scripts/embed-dashboard-ui.sh

@@ -0,0 +1,42 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+BASE_DIR=$(git rev-parse --show-toplevel)
+CACHE_DIR=${BASE_DIR}/.cache
+
+echo '+ Create cache directory'
+mkdir -p ${CACHE_DIR}
+
+echo '+ Fetch Dashboard Go module'
+go mod download
+
+echo '+ Discover Dashboard UI version'
+
+DASHBOARD_DIR=$(go list -f "{{.Dir}}" -m github.com/pingcap-incubator/tidb-dashboard)
+echo "  - Dashboard directory: ${DASHBOARD_DIR}"
+
+DASHBOARD_UI_VERSION=$(grep -v '^#' ${DASHBOARD_DIR}/ui/.github_release_version)
+echo "  - Dashboard ui version: ${DASHBOARD_UI_VERSION}"
+
+echo '+ Check embedded assets exists in cache'
+CACHE_FILE=${CACHE_DIR}/embedded-assets-golang-${DASHBOARD_UI_VERSION}.zip
+if [[ -f "$CACHE_FILE" ]]; then
+  echo "  - Cached archive exists: ${CACHE_FILE}"
+else
+  echo '  - Cached archive does not exist'
+  echo '  - Download pre-built embedded assets from GitHub release'
+
+  DOWNLOAD_URL="https://github.com/pingcap-incubator/tidb-dashboard/releases/download/ui_release_${DASHBOARD_UI_VERSION}/embedded-assets-golang.zip"
+  echo "  - Download ${DOWNLOAD_URL}"
+  curl -L ${DOWNLOAD_URL} > embedded-assets-golang.zip
+
+  echo "  - Save archive to cache: ${CACHE_FILE}"
+  mv embedded-assets-golang.zip ${CACHE_FILE}
+fi
+
+echo '+ Unpack embedded asset from archive'
+unzip -o ${CACHE_FILE}
+MOVE_FILE=embedded_assets_handler.go
+MOVE_DEST=pkg/dashboard/uiserver
+mv ${MOVE_FILE} ${MOVE_DEST}
+echo "  - Unpacked ${MOVE_DEST}/${MOVE_FILE}"

server/server.go

@@ -29,12 +29,14 @@ import (
 	"github.com/coreos/go-semver/semver"
 	"github.com/golang/protobuf/proto"
 	"github.com/gorilla/mux"
+	"github.com/pingcap-incubator/tidb-dashboard/pkg/apiserver"
 	"github.com/pingcap/failpoint"
 	"github.com/pingcap/kvproto/pkg/configpb"
 	"github.com/pingcap/kvproto/pkg/diagnosticspb"
 	"github.com/pingcap/kvproto/pkg/metapb"
 	"github.com/pingcap/kvproto/pkg/pdpb"
 	"github.com/pingcap/log"
+	"github.com/pingcap/pd/pkg/dashboard/uiserver"
 	"github.com/pingcap/pd/pkg/etcdutil"
 	"github.com/pingcap/pd/pkg/logutil"
 	"github.com/pingcap/pd/pkg/typeutil"
@@ -64,10 +66,12 @@ const (
 	serverMetricsInterval = time.Minute
 	leaderTickInterval    = 50 * time.Millisecond
 	// pdRootPath for all pd servers.
-	pdRootPath      = "/pd"
-	pdAPIPrefix     = "/pd/"
-	webPath         = "/web/"
-	pdClusterIDPath = "/pd/cluster_id"
+	pdRootPath       = "/pd"
+	pdAPIPrefix      = "/pd/"
+	webPath          = "/web/"
+	dashboardUIPath  = "/dashboard/"
+	dashboardAPIPath = "/dashboard/api/"
+	pdClusterIDPath  = "/pd/cluster_id"
 )
 
 var (
@@ -206,8 +210,10 @@ func CreateServer(ctx context.Context, cfg *config.Config, apiBuilders ...Handle
 		}
 
 		etcdCfg.UserHandlers = map[string]http.Handler{
-			pdAPIPrefix: apiHandler,
-			webPath:     http.StripPrefix(webPath, ui.Handler()),
+			pdAPIPrefix:      apiHandler,
+			webPath:          http.StripPrefix(webPath, ui.Handler()),
+			dashboardUIPath:  http.StripPrefix(dashboardUIPath, uiserver.Handler()),
+			dashboardAPIPath: apiserver.Handler(dashboardAPIPath),
 		}
 	}
 	etcdCfg.ServiceRegister = func(gs *grpc.Server) {