services/ws/router.go

   1 // Copyright (C) The Arvados Authors. All rights reserved.
   2 //
   3 // SPDX-License-Identifier: AGPL-3.0
   4
   5 package ws
   6
   7 import (
   8         "encoding/json"
   9         "io"
  10         "net/http"
  11         "strconv"
  12         "sync"
  13         "sync/atomic"
  14         "time"
  15
  16         "git.arvados.org/arvados.git/lib/cmd"
  17         "git.arvados.org/arvados.git/sdk/go/arvados"
  18         "git.arvados.org/arvados.git/sdk/go/ctxlog"
  19         "git.arvados.org/arvados.git/sdk/go/health"
  20         "github.com/sirupsen/logrus"
  21         "golang.org/x/net/websocket"
  22 )
  23
  24 type wsConn interface {
  25         io.ReadWriter
  26         Request() *http.Request
  27         SetReadDeadline(time.Time) error
  28         SetWriteDeadline(time.Time) error
  29 }
  30
  31 type router struct {
  32         client         *arvados.Client
  33         cluster        *arvados.Cluster
  34         eventSource    eventSource
  35         newPermChecker func() permChecker
  36
  37         handler   *handler
  38         mux       *http.ServeMux
  39         setupOnce sync.Once
  40         done      chan struct{}
  41
  42         lastReqID  int64
  43         lastReqMtx sync.Mutex
  44
  45         status routerDebugStatus
  46 }
  47
  48 type routerDebugStatus struct {
  49         ReqsReceived int64
  50         ReqsActive   int64
  51 }
  52
  53 type debugStatuser interface {
  54         DebugStatus() interface{}
  55 }
  56
  57 func (rtr *router) setup() {
  58         rtr.handler = &handler{
  59                 PingTimeout: time.Duration(rtr.cluster.API.SendTimeout),
  60                 QueueSize:   rtr.cluster.API.WebsocketClientEventQueue,
  61         }
  62         rtr.mux = http.NewServeMux()
  63         rtr.mux.Handle("/websocket", rtr.makeServer(newSessionV0))
  64         rtr.mux.Handle("/arvados/v1/events.ws", rtr.makeServer(newSessionV1))
  65         rtr.mux.Handle("/debug.json", rtr.jsonHandler(rtr.DebugStatus))
  66         rtr.mux.Handle("/status.json", rtr.jsonHandler(rtr.Status))
  67
  68         rtr.mux.Handle("/_health/", &health.Handler{
  69                 Token:  rtr.cluster.ManagementToken,
  70                 Prefix: "/_health/",
  71                 Routes: health.Routes{
  72                         "db": rtr.eventSource.DBHealth,
  73                 },
  74                 Log: func(r *http.Request, err error) {
  75                         if err != nil {
  76                                 ctxlog.FromContext(r.Context()).WithError(err).Error("error")
  77                         }
  78                 },
  79         })
  80 }
  81
  82 func (rtr *router) makeServer(newSession sessionFactory) *websocket.Server {
  83         return &websocket.Server{
  84                 Handshake: func(c *websocket.Config, r *http.Request) error {
  85                         return nil
  86                 },
  87                 Handler: websocket.Handler(func(ws *websocket.Conn) {
  88                         t0 := time.Now()
  89                         logger := ctxlog.FromContext(ws.Request().Context())
  90                         logger.Info("connected")
  91
  92                         stats := rtr.handler.Handle(ws, logger, rtr.eventSource,
  93                                 func(ws wsConn, sendq chan<- interface{}) (session, error) {
  94                                         return newSession(ws, sendq, rtr.eventSource.DB(), rtr.newPermChecker(), rtr.client)
  95                                 })
  96
  97                         logger.WithFields(logrus.Fields{
  98                                 "elapsed": time.Now().Sub(t0).Seconds(),
  99                                 "stats":   stats,
 100                         }).Info("disconnect")
 101                         ws.Close()
 102                 }),
 103         }
 104 }
 105
 106 func (rtr *router) newReqID() string {
 107         rtr.lastReqMtx.Lock()
 108         defer rtr.lastReqMtx.Unlock()
 109         id := time.Now().UnixNano()
 110         if id <= rtr.lastReqID {
 111                 id = rtr.lastReqID + 1
 112         }
 113         return strconv.FormatInt(id, 36)
 114 }
 115
 116 func (rtr *router) DebugStatus() interface{} {
 117         s := map[string]interface{}{
 118                 "HTTP":     rtr.status,
 119                 "Outgoing": rtr.handler.DebugStatus(),
 120         }
 121         if es, ok := rtr.eventSource.(debugStatuser); ok {
 122                 s["EventSource"] = es.DebugStatus()
 123         }
 124         return s
 125 }
 126
 127 func (rtr *router) Status() interface{} {
 128         return map[string]interface{}{
 129                 "Clients": atomic.LoadInt64(&rtr.status.ReqsActive),
 130                 "Version": cmd.Version.String(),
 131         }
 132 }
 133
 134 func (rtr *router) ServeHTTP(resp http.ResponseWriter, req *http.Request) {
 135         rtr.setupOnce.Do(rtr.setup)
 136         atomic.AddInt64(&rtr.status.ReqsReceived, 1)
 137         atomic.AddInt64(&rtr.status.ReqsActive, 1)
 138         defer atomic.AddInt64(&rtr.status.ReqsActive, -1)
 139
 140         logger := ctxlog.FromContext(req.Context()).
 141                 WithField("RequestID", rtr.newReqID())
 142         ctx := ctxlog.Context(req.Context(), logger)
 143         req = req.WithContext(ctx)
 144         logger.WithFields(logrus.Fields{
 145                 "remoteAddr":      req.RemoteAddr,
 146                 "reqForwardedFor": req.Header.Get("X-Forwarded-For"),
 147         }).Info("accept request")
 148         rtr.mux.ServeHTTP(resp, req)
 149 }
 150
 151 func (rtr *router) jsonHandler(fn func() interface{}) http.Handler {
 152         return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 153                 logger := ctxlog.FromContext(r.Context())
 154                 w.Header().Set("Content-Type", "application/json")
 155                 enc := json.NewEncoder(w)
 156                 err := enc.Encode(fn())
 157                 if err != nil {
 158                         msg := "encode failed"
 159                         logger.WithError(err).Error(msg)
 160                         http.Error(w, msg, http.StatusInternalServerError)
 161                 }
 162         })
 163 }
 164
 165 func (rtr *router) CheckHealth() error {
 166         rtr.setupOnce.Do(rtr.setup)
 167         return rtr.eventSource.DBHealth()
 168 }
 169
 170 func (rtr *router) Done() <-chan struct{} {
 171         return rtr.done
 172 }