Websockets; working

docs/config.md

@@ -549,7 +549,7 @@ variable before running the `ntfy` command (e.g. `export NTFY_LISTEN_HTTP=:80`).
 | `smtp-server-listen`                       | `NTFY_SMTP_SERVER_LISTEN`                       | `[ip]:port`      | -       | Defines the IP address and port the SMTP server will listen on, e.g. `:25` or `1.2.3.4:25`                                                                                                                                      |
 | `smtp-server-domain`                       | `NTFY_SMTP_SERVER_DOMAIN`                       | *domain name*    | -       | SMTP server e-mail domain, e.g. `ntfy.sh`                                                                                                                                                                                       |
 | `smtp-server-addr-prefix`                  | `NTFY_SMTP_SERVER_ADDR_PREFIX`                  | `[ip]:port`      | -       | Optional prefix for the e-mail addresses to prevent spam, e.g. `ntfy-`                                                                                                                                                          |
-| `keepalive-interval`                       | `NTFY_KEEPALIVE_INTERVAL`                       | *duration*       | 55s     | Interval in which keepalive messages are sent to the client. This is to prevent intermediaries closing the connection for inactivity. Note that the Android app has a hardcoded timeout at 77s, so it should be less than that. |
+| `keepalive-interval`                       | `NTFY_KEEPALIVE_INTERVAL`                       | *duration*       | 45s     | Interval in which keepalive messages are sent to the client. This is to prevent intermediaries closing the connection for inactivity. Note that the Android app has a hardcoded timeout at 77s, so it should be less than that. |
 | `manager-interval`                         | `$NTFY_MANAGER_INTERVAL`                        | *duration*       | 1m      | Interval in which the manager prunes old messages, deletes topics and prints the stats.                                                                                                                                         |
 | `global-topic-limit`                       | `NTFY_GLOBAL_TOPIC_LIMIT`                       | *number*         | 15,000  | Rate limiting: Total number of topics before the server rejects new topics.                                                                                                                                                     |
 | `visitor-subscription-limit`               | `NTFY_VISITOR_SUBSCRIPTION_LIMIT`               | *number*         | 30      | Rate limiting: Number of subscriptions per visitor (IP address)                                                                                                                                                                 |
@@ -597,7 +597,7 @@ OPTIONS:
    --attachment-total-size-limit value, -A value     limit of the on-disk attachment cache (default: 5G) [$NTFY_ATTACHMENT_TOTAL_SIZE_LIMIT]
    --attachment-file-size-limit value, -Y value      per-file attachment size limit (e.g. 300k, 2M, 100M) (default: 15M) [$NTFY_ATTACHMENT_FILE_SIZE_LIMIT]
    --attachment-expiry-duration value, -X value      duration after which uploaded attachments will be deleted (e.g. 3h, 20h) (default: 3h) [$NTFY_ATTACHMENT_EXPIRY_DURATION]
-   --keepalive-interval value, -k value              interval of keepalive messages (default: 55s) [$NTFY_KEEPALIVE_INTERVAL]
+   --keepalive-interval value, -k value              interval of keepalive messages (default: 45s) [$NTFY_KEEPALIVE_INTERVAL]
    --manager-interval value, -m value                interval of for message pruning and stats printing (default: 1m0s) [$NTFY_MANAGER_INTERVAL]
    --smtp-sender-addr value                          SMTP server address (host:port) for outgoing emails [$NTFY_SMTP_SENDER_ADDR]
    --smtp-sender-user value                          SMTP user (if e-mail sending is enabled) [$NTFY_SMTP_SENDER_USER]

go.mod

@@ -35,11 +35,13 @@ require (
 	github.com/golang/protobuf v1.5.2 // indirect
 	github.com/google/go-cmp v0.5.6 // indirect
 	github.com/googleapis/gax-go/v2 v2.1.1 // indirect
+	github.com/gorilla/websocket v1.4.2 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/russross/blackfriday/v2 v2.1.0 // indirect
 	go.opencensus.io v0.23.0 // indirect
 	golang.org/x/net v0.0.0-20210813160813-60bc85c4be6d // indirect
+	golang.org/x/sync v0.0.0-20210220032951-036812b2e83c // indirect
 	golang.org/x/sys v0.0.0-20211210111614-af8b64212486 // indirect
 	golang.org/x/text v0.3.7 // indirect
 	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect

go.sum

@@ -189,6 +189,8 @@ github.com/googleapis/gax-go/v2 v2.0.5/go.mod h1:DWXyrwAJ9X0FpwwEdw+IPEYBICEFu5m
 github.com/googleapis/gax-go/v2 v2.1.0/go.mod h1:Q3nei7sK6ybPYH7twZdmQpAd1MKb7pfu6SK+H1/DsU0=
 github.com/googleapis/gax-go/v2 v2.1.1 h1:dp3bWCh+PPO1zjRRiCSczJav13sBvG4UhNyVTa1KqdU=
 github.com/googleapis/gax-go/v2 v2.1.1/go.mod h1:hddJymUZASv3XPyGkUpKj8pPO47Rmb0eJc8R6ouapiM=
+github.com/gorilla/websocket v1.4.2 h1:+/TMaTYc4QFitKJxsQ7Yye35DkWvkdLcvGKqM+x0Ufc=
+github.com/gorilla/websocket v1.4.2/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/grpc-ecosystem/grpc-gateway v1.16.0/go.mod h1:BDjrQk3hbvj6Nolgz8mAMFbcEtjT1g+wF4CSlocrBnw=
 github.com/hashicorp/golang-lru v0.5.0/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ4Ao+sR/qLZy8=
 github.com/hashicorp/golang-lru v0.5.1/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ4Ao+sR/qLZy8=
@@ -356,6 +358,7 @@ golang.org/x/sync v0.0.0-20200317015054-43a5402ce75a/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sync v0.0.0-20200625203802-6e8e738ad208/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.0.0-20210220032951-036812b2e83c h1:5KslGYwFpkhGh+Q16bwMP3cOontH8FOep7tGV86Y7SQ=
 golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=

server/config.go

@@ -8,7 +8,7 @@ import (
 const (
 	DefaultListenHTTP                = ":80"
 	DefaultCacheDuration             = 12 * time.Hour
-	DefaultKeepaliveInterval         = 55 * time.Second // Not too frequently to save battery (Android read timeout is 77s!)
+	DefaultKeepaliveInterval         = 45 * time.Second // Not too frequently to save battery (Android read timeout used to be 77s!)
 	DefaultManagerInterval           = time.Minute
 	DefaultAtSenderInterval          = 10 * time.Second
 	DefaultMinDelay                  = 10 * time.Second

server/server.go

@@ -10,6 +10,8 @@ import (
 	"firebase.google.com/go/messaging"
 	"fmt"
 	"github.com/emersion/go-smtp"
+	"github.com/gorilla/websocket"
+	"golang.org/x/sync/errgroup"
 	"google.golang.org/api/option"
 	"heckel.io/ntfy/util"
 	"html/template"
@@ -99,6 +101,7 @@ var (
 	jsonPathRegex    = regexp.MustCompile(`^/[-_A-Za-z0-9]{1,64}(,[-_A-Za-z0-9]{1,64})*/json$`)
 	ssePathRegex     = regexp.MustCompile(`^/[-_A-Za-z0-9]{1,64}(,[-_A-Za-z0-9]{1,64})*/sse$`)
 	rawPathRegex     = regexp.MustCompile(`^/[-_A-Za-z0-9]{1,64}(,[-_A-Za-z0-9]{1,64})*/raw$`)
+	wsPathRegex      = regexp.MustCompile(`^/[-_A-Za-z0-9]{1,64}(,[-_A-Za-z0-9]{1,64})*/ws$`)
 	publishPathRegex = regexp.MustCompile(`^/[-_A-Za-z0-9]{1,64}(,[-_A-Za-z0-9]{1,64})*/(publish|send|trigger)$`)
 
 	staticRegex      = regexp.MustCompile(`^/static/.+`)
@@ -156,6 +159,10 @@ const (
 	emptyMessageBody         = "triggered"               // Used if message body is empty
 	defaultAttachmentMessage = "You received a file: %s" // Used if message body is empty, and there is an attachment
 	fcmMessageLimit          = 4000                      // see maybeTruncateFCMMessage for details
+	wsWriteWait              = 2 * time.Second
+	wsBufferSize             = 1024
+	wsReadLimit              = 64 // We only ever receive PINGs
+	wsPongWait               = 15 * time.Second
 )
 
 // New instantiates a new Server. It creates the cache and adds a Firebase
@@ -404,6 +411,8 @@ func (s *Server) handleInternal(w http.ResponseWriter, r *http.Request) error {
 		return s.withRateLimit(w, r, s.handleSubscribeSSE)
 	} else if r.Method == http.MethodGet && rawPathRegex.MatchString(r.URL.Path) {
 		return s.withRateLimit(w, r, s.handleSubscribeRaw)
+	} else if r.Method == http.MethodGet && wsPathRegex.MatchString(r.URL.Path) {
+		return s.withRateLimit(w, r, s.handleSubscribeWS)
 	}
 	return errHTTPNotFound
 }
@@ -805,6 +814,106 @@ func (s *Server) handleSubscribe(w http.ResponseWriter, r *http.Request, v *visi
 	}
 }
 
+func (s *Server) handleSubscribeWS(w http.ResponseWriter, r *http.Request, v *visitor) error {
+	if err := v.SubscriptionAllowed(); err != nil {
+		return errHTTPTooManyRequestsLimitSubscriptions
+	}
+	defer v.RemoveSubscription()
+	topicsStr := strings.TrimSuffix(r.URL.Path[1:], "/ws") // Hack
+	topicIDs := util.SplitNoEmpty(topicsStr, ",")
+	topics, err := s.topicsFromIDs(topicIDs...)
+	if err != nil {
+		return err
+	}
+	poll := readParam(r, "x-poll", "poll", "po") == "1"
+	scheduled := readParam(r, "x-scheduled", "scheduled", "sched") == "1"
+	since, err := parseSince(r, poll)
+	if err != nil {
+		return err
+	}
+	messageFilter, titleFilter, priorityFilter, tagsFilter, err := parseQueryFilters(r)
+	if err != nil {
+		return err
+	}
+	upgrader := &websocket.Upgrader{
+		ReadBufferSize:  wsBufferSize,
+		WriteBufferSize: wsBufferSize,
+		CheckOrigin: func(r *http.Request) bool {
+			return true // We're open for business!
+		},
+	}
+	conn, err := upgrader.Upgrade(w, r, nil)
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+	g, ctx := errgroup.WithContext(context.Background())
+	g.Go(func() error {
+		pongWait := s.config.KeepaliveInterval + wsPongWait
+		conn.SetReadLimit(wsReadLimit)
+		if err := conn.SetReadDeadline(time.Now().Add(pongWait)); err != nil {
+			return err
+		}
+		conn.SetPongHandler(func(appData string) error {
+			return conn.SetReadDeadline(time.Now().Add(pongWait))
+		})
+		for {
+			_, _, err := conn.NextReader()
+			if err != nil {
+				return err
+			}
+		}
+	})
+	g.Go(func() error {
+		ping := func() error {
+			if err := conn.SetWriteDeadline(time.Now().Add(wsWriteWait)); err != nil {
+				return err
+			}
+			return conn.WriteMessage(websocket.PingMessage, nil)
+		}
+		for {
+			select {
+			case <-ctx.Done():
+				return nil
+			case <-time.After(s.config.KeepaliveInterval):
+				v.Keepalive()
+				if err := ping(); err != nil {
+					return err
+				}
+			}
+		}
+	})
+	sub := func(msg *message) error {
+		if !passesQueryFilter(msg, messageFilter, titleFilter, priorityFilter, tagsFilter) {
+			return nil
+		}
+		if err := conn.SetWriteDeadline(time.Now().Add(wsWriteWait)); err != nil {
+			return err
+		}
+		return conn.WriteJSON(msg)
+	}
+	w.Header().Set("Access-Control-Allow-Origin", "*") // CORS, allow cross-origin requests
+	if poll {
+		return s.sendOldMessages(topics, since, scheduled, sub)
+	}
+	subscriberIDs := make([]int, 0)
+	for _, t := range topics {
+		subscriberIDs = append(subscriberIDs, t.Subscribe(sub))
+	}
+	defer func() {
+		for i, subscriberID := range subscriberIDs {
+			topics[i].Unsubscribe(subscriberID) // Order!
+		}
+	}()
+	if err := sub(newOpenMessage(topicsStr)); err != nil { // Send out open message
+		return err
+	}
+	if err := s.sendOldMessages(topics, since, scheduled, sub); err != nil {
+		return err
+	}
+	return g.Wait()
+}
+
 func parseQueryFilters(r *http.Request) (messageFilter string, titleFilter string, priorityFilter []int, tagsFilter []string, err error) {
 	messageFilter = readParam(r, "x-message", "message", "m")
 	titleFilter = readParam(r, "x-title", "title", "t")

server/server.yml

@@ -98,7 +98,7 @@
 #
 # Note that the Android app has a hardcoded timeout at 77s, so it should be less than that.
 #
-# keepalive-interval: "30s"
+# keepalive-interval: "45s"
 
 # Interval in which the manager prunes old messages, deletes topics
 # and prints the stats.