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
  41         lastReqID  int64
  42         lastReqMtx sync.Mutex
  43
  44         status routerDebugStatus
  45 }
  46
  47 type routerDebugStatus struct {
  48         ReqsReceived int64
  49         ReqsActive   int64
  50 }
  51
  52 type debugStatuser interface {
  53         DebugStatus() interface{}
  54 }
  55
  56 func (rtr *router) setup() {
  57         rtr.handler = &handler{
  58                 PingTimeout: time.Duration(rtr.cluster.API.SendTimeout),
  59                 QueueSize:   rtr.cluster.API.WebsocketClientEventQueue,
  60         }
  61         rtr.mux = http.NewServeMux()
  62         rtr.mux.Handle("/websocket", rtr.makeServer(newSessionV0))
  63         rtr.mux.Handle("/arvados/v1/events.ws", rtr.makeServer(newSessionV1))
  64         rtr.mux.Handle("/debug.json", rtr.jsonHandler(rtr.DebugStatus))
  65         rtr.mux.Handle("/status.json", rtr.jsonHandler(rtr.Status))
  66
  67         rtr.mux.Handle("/_health/", &health.Handler{
  68                 Token:  rtr.cluster.ManagementToken,
  69                 Prefix: "/_health/",
  70                 Routes: health.Routes{
  71                         "db": rtr.eventSource.DBHealth,
  72                 },
  73                 Log: func(r *http.Request, err error) {
  74                         if err != nil {
  75                                 ctxlog.FromContext(r.Context()).WithError(err).Error("error")
  76                         }
  77                 },
  78         })
  79 }
  80
  81 func (rtr *router) makeServer(newSession sessionFactory) *websocket.Server {
  82         return &websocket.Server{
  83                 Handshake: func(c *websocket.Config, r *http.Request) error {
  84                         return nil
  85                 },
  86                 Handler: websocket.Handler(func(ws *websocket.Conn) {
  87                         t0 := time.Now()
  88                         logger := ctxlog.FromContext(ws.Request().Context())
  89                         logger.Info("connected")
  90
  91                         stats := rtr.handler.Handle(ws, logger, rtr.eventSource,
  92                                 func(ws wsConn, sendq chan<- interface{}) (session, error) {
  93                                         return newSession(ws, sendq, rtr.eventSource.DB(), rtr.newPermChecker(), rtr.client)
  94                                 })
  95
  96                         logger.WithFields(logrus.Fields{
  97                                 "elapsed": time.Now().Sub(t0).Seconds(),
  98                                 "stats":   stats,
  99                         }).Info("disconnect")
 100                         ws.Close()
 101                 }),
 102         }
 103 }
 104
 105 func (rtr *router) newReqID() string {
 106         rtr.lastReqMtx.Lock()
 107         defer rtr.lastReqMtx.Unlock()
 108         id := time.Now().UnixNano()
 109         if id <= rtr.lastReqID {
 110                 id = rtr.lastReqID + 1
 111         }
 112         return strconv.FormatInt(id, 36)
 113 }
 114
 115 func (rtr *router) DebugStatus() interface{} {
 116         s := map[string]interface{}{
 117                 "HTTP":     rtr.status,
 118                 "Outgoing": rtr.handler.DebugStatus(),
 119         }
 120         if es, ok := rtr.eventSource.(debugStatuser); ok {
 121                 s["EventSource"] = es.DebugStatus()
 122         }
 123         return s
 124 }
 125
 126 func (rtr *router) Status() interface{} {
 127         return map[string]interface{}{
 128                 "Clients": atomic.LoadInt64(&rtr.status.ReqsActive),
 129                 "Version": cmd.Version.String(),
 130         }
 131 }
 132
 133 func (rtr *router) ServeHTTP(resp http.ResponseWriter, req *http.Request) {
 134         rtr.setupOnce.Do(rtr.setup)
 135         atomic.AddInt64(&rtr.status.ReqsReceived, 1)
 136         atomic.AddInt64(&rtr.status.ReqsActive, 1)
 137         defer atomic.AddInt64(&rtr.status.ReqsActive, -1)
 138
 139         logger := ctxlog.FromContext(req.Context()).
 140                 WithField("RequestID", rtr.newReqID())
 141         ctx := ctxlog.Context(req.Context(), logger)
 142         req = req.WithContext(ctx)
 143         logger.WithFields(logrus.Fields{
 144                 "remoteAddr":      req.RemoteAddr,
 145                 "reqForwardedFor": req.Header.Get("X-Forwarded-For"),
 146         }).Info("accept request")
 147         rtr.mux.ServeHTTP(resp, req)
 148 }
 149
 150 func (rtr *router) jsonHandler(fn func() interface{}) http.Handler {
 151         return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 152                 logger := ctxlog.FromContext(r.Context())
 153                 w.Header().Set("Content-Type", "application/json")
 154                 enc := json.NewEncoder(w)
 155                 err := enc.Encode(fn())
 156                 if err != nil {
 157                         msg := "encode failed"
 158                         logger.WithError(err).Error(msg)
 159                         http.Error(w, msg, http.StatusInternalServerError)
 160                 }
 161         })
 162 }
 163
 164 func (rtr *router) CheckHealth() error {
 165         rtr.setupOnce.Do(rtr.setup)
 166         return rtr.eventSource.DBHealth()
 167 }