Bump version

client/client_test.go

@@ -37,6 +37,8 @@ func TestClient_Publish_Subscribe(t *testing.T) {
 	require.Equal(t, "some delayed message", msg.Message)
 	require.True(t, time.Now().Add(24*time.Hour).Unix() < msg.Time)
 
+	time.Sleep(200 * time.Millisecond)
+
 	msg = nextMessage(c)
 	require.NotNil(t, msg)
 	require.Equal(t, "some message", msg.Message)

client/options.go

@@ -45,6 +45,11 @@ func WithDelay(delay string) PublishOption {
 	return WithHeader("X-Delay", delay)
 }
 
+// WithEmail instructs the server to also send the message to the given e-mail address
+func WithEmail(email string) PublishOption {
+	return WithHeader("X-Email", email)
+}
+
 // WithNoCache instructs the server not to cache the message server-side
 func WithNoCache() PublishOption {
 	return WithHeader("X-Cache", "no")

cmd/app.go

@@ -7,7 +7,6 @@ import (
 	"github.com/urfave/cli/v2/altsrc"
 	"heckel.io/ntfy/util"
 	"os"
-	"strings"
 )
 
 var (
@@ -60,7 +59,3 @@ func initConfigFileInputSource(configFlag string, flags []cli.Flag) cli.BeforeFu
 		return altsrc.ApplyInputSourceValues(context, inputSource, flags)
 	}
 }
-
-func collapseTopicURL(s string) string {
-	return strings.TrimPrefix(strings.TrimPrefix(s, "https://"), "http://")
-}

cmd/app_test.go

@@ -2,10 +2,13 @@ package cmd
 
 import (
 	"bytes"
+	"encoding/json"
 	"github.com/urfave/cli/v2"
+	"heckel.io/ntfy/client"
 	"io"
 	"log"
 	"os"
+	"strings"
 	"testing"
 )
 
@@ -24,3 +27,11 @@ func newTestApp() (*cli.App, *bytes.Buffer, *bytes.Buffer, *bytes.Buffer) {
 	app.ErrWriter = &stderr
 	return app, &stdin, &stdout, &stderr
 }
+
+func toMessage(t *testing.T, s string) *client.Message {
+	var m *client.Message
+	if err := json.NewDecoder(strings.NewReader(s)).Decode(&m); err != nil {
+		t.Fatal(err)
+	}
+	return m
+}

cmd/publish.go

@@ -20,6 +20,7 @@ var cmdPublish = &cli.Command{
 		&cli.StringFlag{Name: "priority", Aliases: []string{"p"}, Usage: "priority of the message (1=min, 2=low, 3=default, 4=high, 5=max)"},
 		&cli.StringFlag{Name: "tags", Aliases: []string{"tag", "T"}, Usage: "comma separated list of tags and emojis"},
 		&cli.StringFlag{Name: "delay", Aliases: []string{"at", "in", "D"}, Usage: "delay/schedule message"},
+		&cli.StringFlag{Name: "email", Aliases: []string{"e-mail", "mail", "e"}, Usage: "also send to e-mail address"},
 		&cli.BoolFlag{Name: "no-cache", Aliases: []string{"C"}, Usage: "do not cache message server-side"},
 		&cli.BoolFlag{Name: "no-firebase", Aliases: []string{"F"}, Usage: "do not forward message to Firebase"},
 		&cli.BoolFlag{Name: "quiet", Aliases: []string{"q"}, Usage: "do print message"},
@@ -33,6 +34,7 @@ Examples:
   ntfy pub --tags=warning,skull backups "Backups failed"  # Add tags/emojis to message
   ntfy pub --delay=10s delayed_topic Laterzz              # Delay message by 10s
   ntfy pub --at=8:30am delayed_topic Laterzz              # Send message at 8:30am
+  ntfy pub -e phil@example.com alerts 'App is down!'      # Also send email to phil@example.com
   ntfy trigger mywebhook                                  # Sending without message, useful for webhooks
 
 Please also check out the docs on publishing messages. Especially for the --tags and --delay options, 
@@ -54,6 +56,7 @@ func execPublish(c *cli.Context) error {
 	priority := c.String("priority")
 	tags := c.String("tags")
 	delay := c.String("delay")
+	email := c.String("email")
 	noCache := c.Bool("no-cache")
 	noFirebase := c.Bool("no-firebase")
 	quiet := c.Bool("quiet")
@@ -75,6 +78,9 @@ func execPublish(c *cli.Context) error {
 	if delay != "" {
 		options = append(options, client.WithDelay(delay))
 	}
+	if email != "" {
+		options = append(options, client.WithEmail(email))
+	}
 	if noCache {
 		options = append(options, client.WithNoCache())
 	}

cmd/publish_test.go

@@ -1,7 +1,9 @@
 package cmd
 
 import (
+	"fmt"
 	"github.com/stretchr/testify/require"
+	"heckel.io/ntfy/test"
 	"heckel.io/ntfy/util"
 	"testing"
 )
@@ -16,3 +18,19 @@ func TestCLI_Publish_Subscribe_Poll_Real_Server(t *testing.T) {
 	require.Nil(t, app2.Run([]string{"ntfy", "subscribe", "--poll", "ntfytest"}))
 	require.Contains(t, stdout.String(), testMessage)
 }
+
+func TestCLI_Publish_Subscribe_Poll(t *testing.T) {
+	s, port := test.StartServer(t)
+	defer test.StopServer(t, s, port)
+	topic := fmt.Sprintf("http://127.0.0.1:%d/mytopic", port)
+
+	app, _, stdout, _ := newTestApp()
+	require.Nil(t, app.Run([]string{"ntfy", "publish", topic, "some message"}))
+	m := toMessage(t, stdout.String())
+	require.Equal(t, "some message", m.Message)
+
+	app2, _, stdout, _ := newTestApp()
+	require.Nil(t, app2.Run([]string{"ntfy", "subscribe", "--poll", topic}))
+	m = toMessage(t, stdout.String())
+	require.Equal(t, "some message", m.Message)
+}

cmd/serve.go

@@ -1,4 +1,3 @@
-// Package cmd provides the ntfy CLI application
 package cmd
 
 import (
@@ -13,6 +12,7 @@ import (
 
 var flagsServe = []cli.Flag{
 	&cli.StringFlag{Name: "config", Aliases: []string{"c"}, EnvVars: []string{"NTFY_CONFIG_FILE"}, Value: "/etc/ntfy/server.yml", DefaultText: "/etc/ntfy/server.yml", Usage: "config file"},
+	altsrc.NewStringFlag(&cli.StringFlag{Name: "base-url", Aliases: []string{"B"}, EnvVars: []string{"NTFY_BASE_URL"}, Usage: "externally visible base URL for this host (e.g. https://ntfy.sh)"}),
 	altsrc.NewStringFlag(&cli.StringFlag{Name: "listen-http", Aliases: []string{"l"}, EnvVars: []string{"NTFY_LISTEN_HTTP"}, Value: server.DefaultListenHTTP, Usage: "ip:port used to as HTTP listen address"}),
 	altsrc.NewStringFlag(&cli.StringFlag{Name: "listen-https", Aliases: []string{"L"}, EnvVars: []string{"NTFY_LISTEN_HTTPS"}, Usage: "ip:port used to as HTTPS listen address"}),
 	altsrc.NewStringFlag(&cli.StringFlag{Name: "key-file", Aliases: []string{"K"}, EnvVars: []string{"NTFY_KEY_FILE"}, Usage: "private key file, if listen-https is set"}),
@@ -22,10 +22,16 @@ var flagsServe = []cli.Flag{
 	altsrc.NewDurationFlag(&cli.DurationFlag{Name: "cache-duration", Aliases: []string{"b"}, EnvVars: []string{"NTFY_CACHE_DURATION"}, Value: server.DefaultCacheDuration, Usage: "buffer messages for this time to allow `since` requests"}),
 	altsrc.NewDurationFlag(&cli.DurationFlag{Name: "keepalive-interval", Aliases: []string{"k"}, EnvVars: []string{"NTFY_KEEPALIVE_INTERVAL"}, Value: server.DefaultKeepaliveInterval, Usage: "interval of keepalive messages"}),
 	altsrc.NewDurationFlag(&cli.DurationFlag{Name: "manager-interval", Aliases: []string{"m"}, EnvVars: []string{"NTFY_MANAGER_INTERVAL"}, Value: server.DefaultManagerInterval, Usage: "interval of for message pruning and stats printing"}),
+	altsrc.NewStringFlag(&cli.StringFlag{Name: "smtp-addr", EnvVars: []string{"NTFY_SMTP_ADDR"}, Usage: "SMTP server address (host:port) to allow email sending"}),
+	altsrc.NewStringFlag(&cli.StringFlag{Name: "smtp-user", EnvVars: []string{"NTFY_SMTP_USER"}, Usage: "SMTP user (if e-mail sending is enabled)"}),
+	altsrc.NewStringFlag(&cli.StringFlag{Name: "smtp-pass", EnvVars: []string{"NTFY_SMTP_PASS"}, Usage: "SMTP password (if e-mail sending is enabled)"}),
+	altsrc.NewStringFlag(&cli.StringFlag{Name: "smtp-from", EnvVars: []string{"NTFY_SMTP_FROM"}, Usage: "SMTP sender address (if e-mail sending is enabled)"}),
 	altsrc.NewIntFlag(&cli.IntFlag{Name: "global-topic-limit", Aliases: []string{"T"}, EnvVars: []string{"NTFY_GLOBAL_TOPIC_LIMIT"}, Value: server.DefaultGlobalTopicLimit, Usage: "total number of topics allowed"}),
-	altsrc.NewIntFlag(&cli.IntFlag{Name: "visitor-subscription-limit", Aliases: []string{"V"}, EnvVars: []string{"NTFY_VISITOR_SUBSCRIPTION_LIMIT"}, Value: server.DefaultVisitorSubscriptionLimit, Usage: "number of subscriptions per visitor"}),
+	altsrc.NewIntFlag(&cli.IntFlag{Name: "visitor-subscription-limit", EnvVars: []string{"NTFY_VISITOR_SUBSCRIPTION_LIMIT"}, Value: server.DefaultVisitorSubscriptionLimit, Usage: "number of subscriptions per visitor"}),
-	altsrc.NewIntFlag(&cli.IntFlag{Name: "visitor-request-limit-burst", Aliases: []string{"B"}, EnvVars: []string{"NTFY_VISITOR_REQUEST_LIMIT_BURST"}, Value: server.DefaultVisitorRequestLimitBurst, Usage: "initial limit of requests per visitor"}),
+	altsrc.NewIntFlag(&cli.IntFlag{Name: "visitor-request-limit-burst", EnvVars: []string{"NTFY_VISITOR_REQUEST_LIMIT_BURST"}, Value: server.DefaultVisitorRequestLimitBurst, Usage: "initial limit of requests per visitor"}),
-	altsrc.NewDurationFlag(&cli.DurationFlag{Name: "visitor-request-limit-replenish", Aliases: []string{"R"}, EnvVars: []string{"NTFY_VISITOR_REQUEST_LIMIT_REPLENISH"}, Value: server.DefaultVisitorRequestLimitReplenish, Usage: "interval at which burst limit is replenished (one per x)"}),
+	altsrc.NewDurationFlag(&cli.DurationFlag{Name: "visitor-request-limit-replenish", EnvVars: []string{"NTFY_VISITOR_REQUEST_LIMIT_REPLENISH"}, Value: server.DefaultVisitorRequestLimitReplenish, Usage: "interval at which burst limit is replenished (one per x)"}),
+	altsrc.NewIntFlag(&cli.IntFlag{Name: "visitor-email-limit-burst", EnvVars: []string{"NTFY_VISITOR_EMAIL_LIMIT_BURST"}, Value: server.DefaultVisitorEmailLimitBurst, Usage: "initial limit of e-mails per visitor"}),
+	altsrc.NewDurationFlag(&cli.DurationFlag{Name: "visitor-email-limit-replenish", EnvVars: []string{"NTFY_VISITOR_EMAIL_LIMIT_REPLENISH"}, Value: server.DefaultVisitorEmailLimitReplenish, Usage: "interval at which burst limit is replenished (one per x)"}),
 	altsrc.NewBoolFlag(&cli.BoolFlag{Name: "behind-proxy", Aliases: []string{"P"}, EnvVars: []string{"NTFY_BEHIND_PROXY"}, Value: false, Usage: "if set, use X-Forwarded-For header to determine visitor IP address (for rate limiting)"}),
 }
 
@@ -52,6 +58,7 @@ func execServe(c *cli.Context) error {
 	}
 
 	// Read all the options
+	baseURL := c.String("base-url")
 	listenHTTP := c.String("listen-http")
 	listenHTTPS := c.String("listen-https")
 	keyFile := c.String("key-file")
@@ -61,10 +68,16 @@ func execServe(c *cli.Context) error {
 	cacheDuration := c.Duration("cache-duration")
 	keepaliveInterval := c.Duration("keepalive-interval")
 	managerInterval := c.Duration("manager-interval")
+	smtpAddr := c.String("smtp-addr")
+	smtpUser := c.String("smtp-user")
+	smtpPass := c.String("smtp-pass")
+	smtpFrom := c.String("smtp-from")
 	globalTopicLimit := c.Int("global-topic-limit")
 	visitorSubscriptionLimit := c.Int("visitor-subscription-limit")
 	visitorRequestLimitBurst := c.Int("visitor-request-limit-burst")
 	visitorRequestLimitReplenish := c.Duration("visitor-request-limit-replenish")
+	visitorEmailLimitBurst := c.Int("visitor-email-limit-burst")
+	visitorEmailLimitReplenish := c.Duration("visitor-email-limit-replenish")
 	behindProxy := c.Bool("behind-proxy")
 
 	// Check values
@@ -82,10 +95,13 @@ func execServe(c *cli.Context) error {
 		return errors.New("if set, certificate file must exist")
 	} else if listenHTTPS != "" && (keyFile == "" || certFile == "") {
 		return errors.New("if listen-https is set, both key-file and cert-file must be set")
+	} else if smtpAddr != "" && (baseURL == "" || smtpUser == "" || smtpPass == "" || smtpFrom == "") {
+		return errors.New("if smtp-addr is set, base-url, smtp-user, smtp-pass and smtp-from must also be set")
 	}
 
 	// Run server
 	conf := server.NewConfig()
+	conf.BaseURL = baseURL
 	conf.ListenHTTP = listenHTTP
 	conf.ListenHTTPS = listenHTTPS
 	conf.KeyFile = keyFile
@@ -95,10 +111,16 @@ func execServe(c *cli.Context) error {
 	conf.CacheDuration = cacheDuration
 	conf.KeepaliveInterval = keepaliveInterval
 	conf.ManagerInterval = managerInterval
+	conf.SMTPAddr = smtpAddr
+	conf.SMTPUser = smtpUser
+	conf.SMTPPass = smtpPass
+	conf.SMTPFrom = smtpFrom
 	conf.GlobalTopicLimit = globalTopicLimit
 	conf.VisitorSubscriptionLimit = visitorSubscriptionLimit
 	conf.VisitorRequestLimitBurst = visitorRequestLimitBurst
 	conf.VisitorRequestLimitReplenish = visitorRequestLimitReplenish
+	conf.VisitorEmailLimitBurst = visitorEmailLimitBurst
+	conf.VisitorEmailLimitReplenish = visitorEmailLimitReplenish
 	conf.BehindProxy = behindProxy
 	s, err := server.New(conf)
 	if err != nil {

cmd/subscribe.go

@@ -180,7 +180,7 @@ func runCommandInternal(c *cli.Context, command string, m *client.Message) error
 	defer os.Remove(scriptFile)
 	verbose := c.Bool("verbose")
 	if verbose {
-		log.Printf("[%s] Executing: %s (for message: %s)", collapseTopicURL(m.TopicURL), command, m.Raw)
+		log.Printf("[%s] Executing: %s (for message: %s)", util.ShortTopicURL(m.TopicURL), command, m.Raw)
 	}
 	cmd := exec.Command("sh", "-c", scriptFile)
 	cmd.Stdin = c.App.Reader

docs/config.md

@@ -35,19 +35,34 @@ the message to the subscribers.
 Subscribers can retrieve cached messaging using the [`poll=1` parameter](subscribe/api.md#poll-for-messages), as well as the
 [`since=` parameter](subscribe/api.md#fetch-cached-messages).
 
+## E-mail notifications
+To allow forwarding messages via e-mail, you can configure an SMTP server for outgoing messages. Once configured, 
+you can set the `X-Email` header to [send messages via e-mail](publish.md#e-mail-notifications) (e.g. 
+`curl -d "hi there" -H "X-Email: phil@example.com" ntfy.sh/mytopic`).
+
+As of today, only SMTP servers with PLAIN auth and STARTLS are supported. To enable e-mail sending, you must set the 
+following settings:
+
+* `base-url` is the root URL for the ntfy server; this is needed for e-mail footer
+* `smtp-addr` is the hostname:port of the SMTP server
+* `smtp-user` and `smtp-pass` are the username and password of the SMTP user
+* `smtp-from` is the e-mail address of the sender
+
+Please also refer to the [rate limiting](#rate-limiting) settings below, specifically `visitor-email-limit-burst` 
+and `visitor-email-limit-burst`. Setting these conservatively is necessary to avoid abuse.
+
 ## Behind a proxy (TLS, etc.)
 !!! warning
     If you are running ntfy behind a proxy, you must set the `behind-proxy` flag. Otherwise, all visitors are
     [rate limited](#rate-limiting) as if they are one.
 
-It may be desirable to run ntfy behind a proxy, e.g. so you can provide TLS certificates using Let's Encrypt using certbot,
+It may be desirable to run ntfy behind a proxy (e.g. nginx, HAproxy or Apache), so you can provide TLS certificates 
-or simply because you'd like to share the ports (80/443) with other services. Whatever your reasons may be, there are a 
+using Let's Encrypt using certbot, or simply because you'd like to share the ports (80/443) with other services. 
-few things to consider. 
+Whatever your reasons may be, there are a few things to consider. 
 
-### Rate limiting
+If you are running ntfy behind a proxy, you should set the `behind-proxy` flag. This will instruct the 
-If you are running ntfy behind a proxy (e.g. nginx, HAproxy or Apache), you should set the `behind-proxy` 
+[rate limiting](#rate-limiting) logic to use the `X-Forwarded-For` header as the primary identifier for a visitor, 
-flag. This will instruct the [rate limiting](#rate-limiting) logic to use the `X-Forwarded-For` header as the primary 
+as opposed to the remote IP address. If the `behind-proxy` flag is not set, all visitors will
-identifier for a visitor, as opposed to the remote IP address. If the `behind-proxy` flag is not set, all visitors will
 be counted as one, because from the perspective of the ntfy server, they all share the proxy's IP address.
 
 === "/etc/ntfy/server.yml"
@@ -214,7 +229,7 @@ firebase-key-file: "/etc/ntfy/ntfy-sh-firebase-adminsdk-ahnce-9f4d6f14b5.json"
 ## Rate limiting
 !!! info
     Be aware that if you are running ntfy behind a proxy, you must set the `behind-proxy` flag. 
-    Otherwise all visitors are rate limited as if they are one.
+    Otherwise, all visitors are rate limited as if they are one.
 
 By default, ntfy runs without authentication, so it is vitally important that we protect the server from abuse or overload.
 There are various limits and rate limits in place that you can use to configure the server. Let's do the easy ones first:
@@ -235,9 +250,14 @@ request every 10s (defined by `visitor-request-limit-replenish`)
 * `visitor-request-limit-burst` is the initial bucket of requests each visitor has. This defaults to 60.
 * `visitor-request-limit-replenish` is the rate at which the bucket is refilled (one request per x). Defaults to 10s.
 
-During normal usage, you shouldn't encounter this limit at all, and even if you burst a few requests shortly (e.g. when you 
+Similarly to the request limit, there is also an e-mail limit (only relevant if [e-mail notifications](#e-mail-notifications) 
-reconnect after a connection drop), it shouldn't have any effect.
+are enabled):
 
+* `visitor-email-limit-burst` is the initial bucket of emails each visitor has. This defaults to 16.
+* `visitor-email-limit-replenish` is the rate at which the bucket is refilled (one email per x). Defaults to 1h.
+
+During normal usage, you shouldn't encounter these limits at all, and even if you burst a few requests or emails
+(e.g. when you reconnect after a connection drop), it shouldn't have any effect.
 
 ## Tuning for scale
 If you're running ntfy for your home server, you probably don't need to worry about scale at all. In its default config,
@@ -300,6 +320,7 @@ variable before running the `ntfy` command (e.g. `export NTFY_LISTEN_HTTP=:80`).
 
 | Config option | Env variable | Format | Default | Description |
 |---|---|---|---|---|
+| `base-url` | `NTFY_BASE_URL` | *URL* | - | Public facing base URL of the service (e.g. `https://ntfy.sh`) |
 | `listen-http` | `NTFY_LISTEN_HTTP` | `[host]:port` | `:80` | Listen address for the HTTP web server |
 | `listen-https` | `NTFY_LISTEN_HTTPS` | `[host]:port` | - | Listen address for the HTTPS web server. If set, you also need to set `key-file` and `cert-file`. |
 | `key-file` | `NTFY_KEY_FILE` | *filename* | - | HTTPS/TLS private key file, only used if `listen-https` is set. |
@@ -307,42 +328,64 @@ variable before running the `ntfy` command (e.g. `export NTFY_LISTEN_HTTP=:80`).
 | `firebase-key-file` | `NTFY_FIREBASE_KEY_FILE` | *filename* | - | If set, also publish messages to a Firebase Cloud Messaging (FCM) topic for your app. This is optional and only required to save battery when using the Android app. See [Firebase (FCM](#firebase-fcm). |
 | `cache-file` | `NTFY_CACHE_FILE` | *filename* | - | If set, messages are cached in a local SQLite database instead of only in-memory. This allows for service restarts without losing messages in support of the since= parameter. See [message cache](#message-cache). |
 | `cache-duration` | `NTFY_CACHE_DURATION` | *duration* | 12h | Duration for which messages will be buffered before they are deleted. This is required to support the `since=...` and `poll=1` parameter. Set this to `0` to disable the cache entirely. |
+| `behind-proxy` | `NTFY_BEHIND_PROXY` | *bool* | false | If set, the X-Forwarded-For header is used to determine the visitor IP address instead of the remote address of the connection. |
+| `smtp-addr` | `NTFY_SMTP_ADDR` | `host:port` | - | SMTP server address to allow email sending |
+| `smtp-user` | `NTFY_SMTP_USER` | *string* | - | SMTP user; only used if e-mail sending is enabled |
+| `smtp-pass` | `NTFY_SMTP_PASS` | *string* | - | SMTP password; only used if e-mail sending is enabled |
+| `smtp-from` | `NTFY_SMTP_FROM` | *e-mail address* | - | SMTP sender e-mail address; only used if e-mail sending is enabled |
 | `keepalive-interval` | `NTFY_KEEPALIVE_INTERVAL` | *duration* | 30s | 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* | 5000 | 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) |
 | `visitor-request-limit-burst` | `NTFY_VISITOR_REQUEST_LIMIT_BURST` | *number* | 60 | Allowed GET/PUT/POST requests per second, per visitor. This setting is the initial bucket of requests each visitor has |
 | `visitor-request-limit-replenish` | `NTFY_VISITOR_REQUEST_LIMIT_REPLENISH` | *duration* | 10s | Strongly related to `visitor-request-limit-burst`: The rate at which the bucket is refilled |
-| `behind-proxy` | `NTFY_BEHIND_PROXY` | *bool* | false | If set, the X-Forwarded-For header is used to determine the visitor IP address instead of the remote address of the connection. |
+| `visitor-email-limit-burst` | `NTFY_VISITOR_EMAIL_LIMIT_BURST` | *number* | 16 |Initial limit of e-mails per visitor |
+| `visitor-email-limit-replenish` | `NTFY_VISITOR_EMAIL_LIMIT_REPLENISH` | *duration* | 1h | Strongly related to `visitor-email-limit-burst`: The rate at which the bucket is refilled |
 
 The format for a *duration* is: `<number>(smh)`, e.g. 30s, 20m or 1h.
 
 ## Command line options
 ```
-$ ntfy --help
+$ ntfy serve --help
 NAME:
-   ntfy - Simple pub-sub notification service
+   ntfy serve - Run the ntfy server
 
 USAGE:
-   ntfy [OPTION..]
+   ntfy serve [OPTIONS..]
 
-GLOBAL OPTIONS:
+DESCRIPTION:
-   --config value, -c value                           config file (default: /etc/ntfy/server.yml) [$NTFY_CONFIG_FILE]
+   Run the ntfy server and listen for incoming requests
-   --listen-http value, -l value                      ip:port used to as listen address (default: ":80") [$NTFY_LISTEN_HTTP]
-   --firebase-key-file value, -F value                Firebase credentials file; if set additionally publish to FCM topic [$NTFY_FIREBASE_KEY_FILE]
-   --cache-file value, -C value                       cache file used for message caching [$NTFY_CACHE_FILE]
-   --cache-duration since, -b since                   buffer messages for this time to allow since requests (default: 12h0m0s) [$NTFY_CACHE_DURATION]
-   --keepalive-interval value, -k value               interval of keepalive messages (default: 30s) [$NTFY_KEEPALIVE_INTERVAL]
-   --manager-interval value, -m value                 interval of for message pruning and stats printing (default: 1m0s) [$NTFY_MANAGER_INTERVAL]
-   --global-topic-limit value, -T value               total number of topics allowed (default: 5000) [$NTFY_GLOBAL_TOPIC_LIMIT]
-   --visitor-subscription-limit value, -V value       number of subscriptions per visitor (default: 30) [$NTFY_VISITOR_SUBSCRIPTION_LIMIT]
-   --visitor-request-limit-burst value, -B value      initial limit of requests per visitor (default: 60) [$NTFY_VISITOR_REQUEST_LIMIT_BURST]
-   --visitor-request-limit-replenish value, -R value  interval at which burst limit is replenished (one per x) (default: 10s) [$NTFY_VISITOR_REQUEST_LIMIT_REPLENISH]
-   --behind-proxy, -P                                 if set, use X-Forwarded-For header to determine visitor IP address (for rate limiting) (default: false) [$NTFY_BEHIND_PROXY]
    
-Try 'ntfy COMMAND --help' for more information.
+   The command will load the configuration from /etc/ntfy/server.yml. Config options can 
+   be overridden using the command line options.
    
-ntfy v1.4.8 (7b8185c), runtime go1.17, built at 1637872539
+   Examples:
-Copyright (C) 2021 Philipp C. Heckel, distributed under the Apache License 2.0
+     ntfy serve                      # Starts server in the foreground (on port 80)
+     ntfy serve --listen-http :8080  # Starts server with alternate port
+
+OPTIONS:
+   --config value, -c value                 config file (default: /etc/ntfy/server.yml) [$NTFY_CONFIG_FILE]
+   --base-url value, -B value               externally visible base URL for this host (e.g. https://ntfy.sh) [$NTFY_BASE_URL]
+   --listen-http value, -l value            ip:port used to as HTTP listen address (default: ":80") [$NTFY_LISTEN_HTTP]
+   --listen-https value, -L value           ip:port used to as HTTPS listen address [$NTFY_LISTEN_HTTPS]
+   --key-file value, -K value               private key file, if listen-https is set [$NTFY_KEY_FILE]
+   --cert-file value, -E value              certificate file, if listen-https is set [$NTFY_CERT_FILE]
+   --firebase-key-file value, -F value      Firebase credentials file; if set additionally publish to FCM topic [$NTFY_FIREBASE_KEY_FILE]
+   --cache-file value, -C value             cache file used for message caching [$NTFY_CACHE_FILE]
+   --cache-duration since, -b since         buffer messages for this time to allow since requests (default: 12h0m0s) [$NTFY_CACHE_DURATION]
+   --keepalive-interval value, -k value     interval of keepalive messages (default: 30s) [$NTFY_KEEPALIVE_INTERVAL]
+   --manager-interval value, -m value       interval of for message pruning and stats printing (default: 1m0s) [$NTFY_MANAGER_INTERVAL]
+   --smtp-addr value                        SMTP server address (host:port) to allow email sending [$NTFY_SMTP_ADDR]
+   --smtp-user value                        SMTP user (if e-mail sending is enabled) [$NTFY_SMTP_USER]
+   --smtp-pass value                        SMTP password (if e-mail sending is enabled) [$NTFY_SMTP_PASS]
+   --smtp-from value                        SMTP sender address (if e-mail sending is enabled) [$NTFY_SMTP_FROM]
+   --global-topic-limit value, -T value     total number of topics allowed (default: 5000) [$NTFY_GLOBAL_TOPIC_LIMIT]
+   --visitor-subscription-limit value       number of subscriptions per visitor (default: 30) [$NTFY_VISITOR_SUBSCRIPTION_LIMIT]
+   --visitor-request-limit-burst value      initial limit of requests per visitor (default: 60) [$NTFY_VISITOR_REQUEST_LIMIT_BURST]
+   --visitor-request-limit-replenish value  interval at which burst limit is replenished (one per x) (default: 10s) [$NTFY_VISITOR_REQUEST_LIMIT_REPLENISH]
+   --visitor-email-limit-burst value        initial limit of e-mails per visitor (default: 16) [$NTFY_VISITOR_EMAIL_LIMIT_BURST]
+   --visitor-email-limit-replenish value    interval at which burst limit is replenished (one per x) (default: 1h0m0s) [$NTFY_VISITOR_EMAIL_LIMIT_REPLENISH]
+   --behind-proxy, -P                       if set, use X-Forwarded-For header to determine visitor IP address (for rate limiting) (default: false) [$NTFY_BEHIND_PROXY]
+   --help, -h                               show help (default: false)
 ```
 

docs/install.md

@@ -26,21 +26,21 @@ deb/rpm packages.
 
 === "x86_64/amd64"
     ```bash
-    wget https://github.com/binwiederhier/ntfy/releases/download/v1.8.0/ntfy_1.8.0_linux_x86_64.tar.gz
+    wget https://github.com/binwiederhier/ntfy/releases/download/v1.9.0/ntfy_1.9.0_linux_x86_64.tar.gz
     sudo tar -C /usr/bin -zxf ntfy_*.tar.gz ntfy
     sudo ./ntfy serve
     ```
 
 === "armv7/armhf"
     ```bash
-    wget https://github.com/binwiederhier/ntfy/releases/download/v1.8.0/ntfy_1.8.0_linux_armv7.tar.gz
+    wget https://github.com/binwiederhier/ntfy/releases/download/v1.9.0/ntfy_1.9.0_linux_armv7.tar.gz
     sudo tar -C /usr/bin -zxf ntfy_*.tar.gz ntfy
     sudo ./ntfy serve
     ```
 
 === "arm64"
     ```bash
-    wget https://github.com/binwiederhier/ntfy/releases/download/v1.8.0/ntfy_1.8.0_linux_arm64.tar.gz
+    wget https://github.com/binwiederhier/ntfy/releases/download/v1.9.0/ntfy_1.9.0_linux_arm64.tar.gz
     sudo tar -C /usr/bin -zxf ntfy_*.tar.gz ntfy
     sudo ./ntfy serve
     ```
@@ -88,7 +88,7 @@ Manually installing the .deb file:
 
 === "x86_64/amd64"
     ```bash
-    wget https://github.com/binwiederhier/ntfy/releases/download/v1.8.0/ntfy_1.8.0_linux_amd64.deb
+    wget https://github.com/binwiederhier/ntfy/releases/download/v1.9.0/ntfy_1.9.0_linux_amd64.deb
     sudo dpkg -i ntfy_*.deb
     sudo systemctl enable ntfy
     sudo systemctl start ntfy
@@ -96,7 +96,7 @@ Manually installing the .deb file:
 
 === "armv7/armhf"
     ```bash
-    wget https://github.com/binwiederhier/ntfy/releases/download/v1.8.0/ntfy_1.8.0_linux_armv7.deb
+    wget https://github.com/binwiederhier/ntfy/releases/download/v1.9.0/ntfy_1.9.0_linux_armv7.deb
     sudo dpkg -i ntfy_*.deb
     sudo systemctl enable ntfy
     sudo systemctl start ntfy
@@ -104,7 +104,7 @@ Manually installing the .deb file:
 
 === "arm64"
     ```bash
-    wget https://github.com/binwiederhier/ntfy/releases/download/v1.8.0/ntfy_1.8.0_linux_arm64.deb
+    wget https://github.com/binwiederhier/ntfy/releases/download/v1.9.0/ntfy_1.9.0_linux_arm64.deb
     sudo dpkg -i ntfy_*.deb
     sudo systemctl enable ntfy
     sudo systemctl start ntfy
@@ -114,21 +114,21 @@ Manually installing the .deb file:
 
 === "x86_64/amd64"
     ```bash
-    sudo rpm -ivh https://github.com/binwiederhier/ntfy/releases/download/v1.8.0/ntfy_1.8.0_linux_amd64.rpm
+    sudo rpm -ivh https://github.com/binwiederhier/ntfy/releases/download/v1.9.0/ntfy_1.9.0_linux_amd64.rpm
     sudo systemctl enable ntfy 
     sudo systemctl start ntfy
     ```
 
 === "armv7/armhf"
     ```bash
-    sudo rpm -ivh https://github.com/binwiederhier/ntfy/releases/download/v1.8.0/ntfy_1.8.0_linux_armv7.rpm
+    sudo rpm -ivh https://github.com/binwiederhier/ntfy/releases/download/v1.9.0/ntfy_1.9.0_linux_armv7.rpm
     sudo systemctl enable ntfy 
     sudo systemctl start ntfy
     ```
 
 === "arm64"
     ```bash
-    sudo rpm -ivh https://github.com/binwiederhier/ntfy/releases/download/v1.8.0/ntfy_1.8.0_linux_arm64.rpm
+    sudo rpm -ivh https://github.com/binwiederhier/ntfy/releases/download/v1.9.0/ntfy_1.9.0_linux_arm64.rpm
     sudo systemctl enable ntfy 
     sudo systemctl start ntfy
     ```

docs/publish.md

@@ -592,6 +592,105 @@ Here's an example with a custom message, tags and a priority:
     file_get_contents('https://ntfy.sh/mywebhook/publish?message=Webhook+triggered&priority=high&tags=warning,skull');
     ```
 
+## E-mail notifications
+You can forward messages to e-mail by specifying an address in the header. This can be useful for messages that 
+you'd like to persist longer, or to blast-notify yourself on all possible channels. 
+
+Usage is easy: Simply pass the `X-Email` header (or any of its aliases: `X-E-mail`, `Email`, `E-mail`, `Mail`, or `e`).
+Only one e-mail address is supported.
+
+Since ntfy does not provide auth (yet), the rate limiting is pretty strict (see [limitations](#limitations)). In the 
+default configuration, you get **16 e-mails per visitor** (IP address) and then after that one per hour. On top of 
+that, your IP address appears in the e-mail body. This is to prevent abuse.
+
+=== "Command line (curl)"
+    ```
+    curl \
+        -H "Email: phil@example.com" \
+        -H "Tags: warning,skull,backup-host,ssh-login" \
+        -H "Priority: high" \
+        -d "Unknown login from 5.31.23.83 to backups.example.com" \
+        ntfy.sh/alerts
+    curl -H "Email: phil@example.com" -d "You've Got Mail" 
+    curl -d "You've Got Mail" "ntfy.sh/alerts?email=phil@example.com"
+    ```
+
+=== "ntfy CLI"
+    ```
+    ntfy publish \
+        --email=phil@example.com \
+        --tags=warning,skull,backup-host,ssh-login \
+        --priority=high \
+        alerts "Unknown login from 5.31.23.83 to backups.example.com"
+    ```
+
+=== "HTTP"
+    ``` http
+    POST /alerts HTTP/1.1
+    Host: ntfy.sh
+    Email: phil@example.com
+    Tags: warning,skull,backup-host,ssh-login
+    Priority: high
+
+    Unknown login from 5.31.23.83 to backups.example.com
+    ```
+
+=== "JavaScript"
+    ``` javascript
+    fetch('https://ntfy.sh/alerts', {
+        method: 'POST',
+        body: "Unknown login from 5.31.23.83 to backups.example.com",
+        headers: { 
+            'Email': 'phil@example.com',
+            'Tags': 'warning,skull,backup-host,ssh-login',
+            'Priority': 'high'
+        }
+    })
+    ```
+
+=== "Go"
+    ``` go
+    req, _ := http.NewRequest("POST", "https://ntfy.sh/alerts", 
+        strings.NewReader("Unknown login from 5.31.23.83 to backups.example.com"))
+    req.Header.Set("Email", "phil@example.com")
+    req.Header.Set("Tags", "warning,skull,backup-host,ssh-login")
+    req.Header.Set("Priority", "high")
+    http.DefaultClient.Do(req)
+    ```
+
+=== "Python"
+    ``` python
+    requests.post("https://ntfy.sh/alerts",
+        data="Unknown login from 5.31.23.83 to backups.example.com",
+        headers={ 
+            "Email": "phil@example.com",
+            "Tags": "warning,skull,backup-host,ssh-login",
+            "Priority": "high"
+        })
+    ```
+
+=== "PHP"
+    ``` php-inline
+    file_get_contents('https://ntfy.sh/alerts', false, stream_context_create([
+        'http' => [
+            'method' => 'POST',
+            'header' =>
+                "Content-Type: text/plain\r\n" .
+                "Email: phil@example.com\r\n" .
+                "Tags: warning,skull,backup-host,ssh-login\r\n" .
+                "Priority: high",
+            'content' => 'Unknown login from 5.31.23.83 to backups.example.com'
+        ]
+    ]));
+    ```
+
+Here's what that looks like in Google Mail:
+
+<figure markdown>
+  ![e-mail notification](static/img/screenshot-email.png){ width=600 }
+  <figcaption>E-mail notification</figcaption>
+</figure>
+
 ## Advanced features
 
 ### Message caching
@@ -746,7 +845,8 @@ but just in case, let's list them all:
 | Limit | Description |
 |---|---|
 | **Message length** | Each message can be up to 512 bytes long. Longer messages are truncated. |
-| **Requests per second** | By default, the server is configured to allow 60 requests at once, and then refills the your allowed requests bucket at a rate of one request per 10 seconds. You can read more about this in the [rate limiting](config.md#rate-limiting) section. |
+| **Requests** | By default, the server is configured to allow 60 requests at once, and then refills the your allowed requests bucket at a rate of one request per 10 seconds. You can read more about this in the [rate limiting](config.md#rate-limiting) section. |
+| **E-mails** | By default, the server is configured to allow 16 e-mails at once, and then refills the your allowed e-mail bucket at a rate of one per hour. You can read more about this in the [rate limiting](config.md#rate-limiting) section. |
 | **Subscription limits** | By default, the server allows each visitor to keep 30 connections to the server open. |
 | **Total number of topics** | By default, the server is configured to allow 5,000 topics. The ntfy.sh server has higher limits though. |
 
@@ -761,5 +861,6 @@ and can be passed as **HTTP headers** or **query parameters in the URL**. They a
 | `X-Priority` | `Priority`, `prio`, `p` | [Message priority](#message-priority) |
 | `X-Tags` | `Tags`, `Tag`, `ta` | [Tags and emojis](#tags-emojis) |
 | `X-Delay` | `Delay`, `X-At`, `At`, `X-In`, `In` | Timestamp or duration for [delayed delivery](#scheduled-delivery) |
+| `X-Email` | `X-E-Mail`, `Email`, `E-Mail`, `mail`, `e` | E-mail address for [e-mail notifications](#e-mail-notifications) |
 | `X-Cache` | `Cache` | Allows disabling [message caching](#message-caching) |
 | `X-Firebase` | `Firebase` | Allows disabling [sending to Firebase](#disable-firebase) |

server/config.go

@@ -20,16 +20,20 @@ const (
 // Defines all the limits
 // - global topic limit: max number of topics overall
 // - per visitor request limit: max number of PUT/GET/.. requests (here: 60 requests bucket, replenished at a rate of one per 10 seconds)
+// - per visitor email limit: max number of emails (here: 16 email bucket, replenished at a rate of one per hour)
 // - per visitor subscription limit: max number of subscriptions (active HTTP connections) per per-visitor/IP
 const (
 	DefaultGlobalTopicLimit             = 5000
 	DefaultVisitorRequestLimitBurst     = 60
 	DefaultVisitorRequestLimitReplenish = 10 * time.Second
+	DefaultVisitorEmailLimitBurst       = 16
+	DefaultVisitorEmailLimitReplenish   = time.Hour
 	DefaultVisitorSubscriptionLimit     = 30
 )
 
 // Config is the main config struct for the application. Use New to instantiate a default config struct.
 type Config struct {
+	BaseURL                      string
 	ListenHTTP                   string
 	ListenHTTPS                  string
 	KeyFile                      string
@@ -41,12 +45,18 @@ type Config struct {
 	ManagerInterval              time.Duration
 	AtSenderInterval             time.Duration
 	FirebaseKeepaliveInterval    time.Duration
+	SMTPAddr                     string
+	SMTPUser                     string
+	SMTPPass                     string
+	SMTPFrom                     string
 	MessageLimit                 int
 	MinDelay                     time.Duration
 	MaxDelay                     time.Duration
 	GlobalTopicLimit             int
 	VisitorRequestLimitBurst     int
 	VisitorRequestLimitReplenish time.Duration
+	VisitorEmailLimitBurst       int
+	VisitorEmailLimitReplenish   time.Duration
 	VisitorSubscriptionLimit     int
 	BehindProxy                  bool
 }
@@ -54,6 +64,7 @@ type Config struct {
 // NewConfig instantiates a default new server config
 func NewConfig() *Config {
 	return &Config{
+		BaseURL:                      "",
 		ListenHTTP:                   DefaultListenHTTP,
 		ListenHTTPS:                  "",
 		KeyFile:                      "",
@@ -71,6 +82,8 @@ func NewConfig() *Config {
 		GlobalTopicLimit:             DefaultGlobalTopicLimit,
 		VisitorRequestLimitBurst:     DefaultVisitorRequestLimitBurst,
 		VisitorRequestLimitReplenish: DefaultVisitorRequestLimitReplenish,
+		VisitorEmailLimitBurst:       DefaultVisitorEmailLimitBurst,
+		VisitorEmailLimitReplenish:   DefaultVisitorEmailLimitReplenish,
 		VisitorSubscriptionLimit:     DefaultVisitorSubscriptionLimit,
 		BehindProxy:                  false,
 	}

server/mailer.go

@@ -0,0 +1,117 @@
+package server
+
+import (
+	_ "embed" // required by go:embed
+	"encoding/json"
+	"fmt"
+	"heckel.io/ntfy/util"
+	"net"
+	"net/smtp"
+	"strings"
+	"time"
+)
+
+type mailer interface {
+	Send(from, to string, m *message) error
+}
+
+type smtpMailer struct {
+	config *Config
+}
+
+func (s *smtpMailer) Send(senderIP, to string, m *message) error {
+	host, _, err := net.SplitHostPort(s.config.SMTPAddr)
+	if err != nil {
+		return err
+	}
+	message, err := formatMail(s.config.BaseURL, senderIP, s.config.SMTPFrom, to, m)
+	if err != nil {
+		return err
+	}
+	auth := smtp.PlainAuth("", s.config.SMTPUser, s.config.SMTPPass, host)
+	return smtp.SendMail(s.config.SMTPAddr, auth, s.config.SMTPFrom, []string{to}, []byte(message))
+}
+
+func formatMail(baseURL, senderIP, from, to string, m *message) (string, error) {
+	topicURL := baseURL + "/" + m.Topic
+	subject := m.Title
+	if subject == "" {
+		subject = m.Message
+	}
+	subject = strings.ReplaceAll(strings.ReplaceAll(subject, "\r", ""), "\n", " ")
+	message := m.Message
+	trailer := ""
+	if len(m.Tags) > 0 {
+		emojis, tags, err := toEmojis(m.Tags)
+		if err != nil {
+			return "", err
+		}
+		if len(emojis) > 0 {
+			subject = strings.Join(emojis, " ") + " " + subject
+		}
+		if len(tags) > 0 {
+			trailer = "Tags: " + strings.Join(tags, ", ")
+		}
+	}
+	if m.Priority != 0 && m.Priority != 3 {
+		priority, err := util.PriorityString(m.Priority)
+		if err != nil {
+			return "", err
+		}
+		if trailer != "" {
+			trailer += "\n"
+		}
+		trailer += fmt.Sprintf("Priority: %s", priority)
+	}
+	if trailer != "" {
+		message += "\n\n" + trailer
+	}
+	body := `Content-Type: text/plain; charset="utf-8"
+From: "{shortTopicURL}" <{from}>
+To: {to}
+Subject: {subject}
+
+{message}
+
+--
+This message was sent by {ip} at {time} via {topicURL}`
+	body = strings.ReplaceAll(body, "{from}", from)
+	body = strings.ReplaceAll(body, "{to}", to)
+	body = strings.ReplaceAll(body, "{subject}", subject)
+	body = strings.ReplaceAll(body, "{message}", message)
+	body = strings.ReplaceAll(body, "{topicURL}", topicURL)
+	body = strings.ReplaceAll(body, "{shortTopicURL}", util.ShortTopicURL(topicURL))
+	body = strings.ReplaceAll(body, "{time}", time.Unix(m.Time, 0).UTC().Format(time.RFC1123))
+	body = strings.ReplaceAll(body, "{ip}", senderIP)
+	return body, nil
+}
+
+var (
+	//go:embed "mailer_emoji.json"
+	emojisJSON string
+)
+
+type emoji struct {
+	Emoji   string   `json:"emoji"`
+	Aliases []string `json:"aliases"`
+}
+
+func toEmojis(tags []string) (emojisOut []string, tagsOut []string, err error) {
+	var emojis []emoji
+	if err = json.Unmarshal([]byte(emojisJSON), &emojis); err != nil {
+		return nil, nil, err
+	}
+	tagsOut = make([]string, 0)
+	emojisOut = make([]string, 0)
+nextTag:
+	for _, t := range tags { // TODO Super inefficient; we should just create a .json file with a map
+		for _, e := range emojis {
+			if util.InStringList(e.Aliases, t) {
+				emojisOut = append(emojisOut, e.Emoji)
+				continue nextTag
+			}
+		}
+		tagsOut = append(tagsOut, t)
+	}
+	return
+}

server/mailer_test.go

@@ -0,0 +1,141 @@
+package server
+
+import (
+	"github.com/stretchr/testify/require"
+	"testing"
+)
+
+func TestFormatMail_Basic(t *testing.T) {
+	actual, _ := formatMail("https://ntfy.sh", "1.2.3.4", "ntfy@ntfy.sh", "phil@example.com", &message{
+		ID:      "abc",
+		Time:    1640382204,
+		Event:   "message",
+		Topic:   "alerts",
+		Message: "A simple message",
+	})
+	expected := `Content-Type: text/plain; charset="utf-8"
+From: "ntfy.sh/alerts" <ntfy@ntfy.sh>
+To: phil@example.com
+Subject: A simple message
+
+A simple message
+
+--
+This message was sent by 1.2.3.4 at Fri, 24 Dec 2021 21:43:24 UTC via https://ntfy.sh/alerts`
+	require.Equal(t, expected, actual)
+}
+
+func TestFormatMail_JustEmojis(t *testing.T) {
+	actual, _ := formatMail("https://ntfy.sh", "1.2.3.4", "ntfy@ntfy.sh", "phil@example.com", &message{
+		ID:      "abc",
+		Time:    1640382204,
+		Event:   "message",
+		Topic:   "alerts",
+		Message: "A simple message",
+		Tags:    []string{"grinning"},
+	})
+	expected := `Content-Type: text/plain; charset="utf-8"
+From: "ntfy.sh/alerts" <ntfy@ntfy.sh>
+To: phil@example.com
+Subject: 😀 A simple message
+
+A simple message
+
+--
+This message was sent by 1.2.3.4 at Fri, 24 Dec 2021 21:43:24 UTC via https://ntfy.sh/alerts`
+	require.Equal(t, expected, actual)
+}
+
+func TestFormatMail_JustOtherTags(t *testing.T) {
+	actual, _ := formatMail("https://ntfy.sh", "1.2.3.4", "ntfy@ntfy.sh", "phil@example.com", &message{
+		ID:      "abc",
+		Time:    1640382204,
+		Event:   "message",
+		Topic:   "alerts",
+		Message: "A simple message",
+		Tags:    []string{"not-an-emoji"},
+	})
+	expected := `Content-Type: text/plain; charset="utf-8"
+From: "ntfy.sh/alerts" <ntfy@ntfy.sh>
+To: phil@example.com
+Subject: A simple message
+
+A simple message
+
+Tags: not-an-emoji
+
+--
+This message was sent by 1.2.3.4 at Fri, 24 Dec 2021 21:43:24 UTC via https://ntfy.sh/alerts`
+	require.Equal(t, expected, actual)
+}
+
+func TestFormatMail_JustPriority(t *testing.T) {
+	actual, _ := formatMail("https://ntfy.sh", "1.2.3.4", "ntfy@ntfy.sh", "phil@example.com", &message{
+		ID:       "abc",
+		Time:     1640382204,
+		Event:    "message",
+		Topic:    "alerts",
+		Message:  "A simple message",
+		Priority: 2,
+	})
+	expected := `Content-Type: text/plain; charset="utf-8"
+From: "ntfy.sh/alerts" <ntfy@ntfy.sh>
+To: phil@example.com
+Subject: A simple message
+
+A simple message
+
+Priority: low
+
+--
+This message was sent by 1.2.3.4 at Fri, 24 Dec 2021 21:43:24 UTC via https://ntfy.sh/alerts`
+	require.Equal(t, expected, actual)
+}
+
+func TestFormatMail_UTF8Subject(t *testing.T) {
+	actual, _ := formatMail("https://ntfy.sh", "1.2.3.4", "ntfy@ntfy.sh", "phil@example.com", &message{
+		ID:      "abc",
+		Time:    1640382204,
+		Event:   "message",
+		Topic:   "alerts",
+		Message: "A simple message",
+		Title:   " :: A not so simple title öäüß ¡Hola, señor!",
+	})
+	expected := `Content-Type: text/plain; charset="utf-8"
+From: "ntfy.sh/alerts" <ntfy@ntfy.sh>
+To: phil@example.com
+Subject:  :: A not so simple title öäüß ¡Hola, señor!
+
+A simple message
+
+--
+This message was sent by 1.2.3.4 at Fri, 24 Dec 2021 21:43:24 UTC via https://ntfy.sh/alerts`
+	require.Equal(t, expected, actual)
+}
+
+func TestFormatMail_WithAllTheThings(t *testing.T) {
+	actual, _ := formatMail("https://ntfy.sh", "1.2.3.4", "ntfy@ntfy.sh", "phil@example.com", &message{
+		ID:       "abc",
+		Time:     1640382204,
+		Event:    "message",
+		Topic:    "alerts",
+		Priority: 5,
+		Tags:     []string{"warning", "skull", "tag123", "other"},
+		Title:    "Oh no 🙈\nThis is a message across\nmultiple lines",
+		Message:  "A message that contains monkeys 🙉\nNo really, though. Monkeys!",
+	})
+	expected := `Content-Type: text/plain; charset="utf-8"
+From: "ntfy.sh/alerts" <ntfy@ntfy.sh>
+To: phil@example.com
+Subject: ⚠️ 💀 Oh no 🙈 This is a message across multiple lines
+
+A message that contains monkeys 🙉
+No really, though. Monkeys!
+
+Tags: tag123, other
+Priority: max
+
+--
+This message was sent by 1.2.3.4 at Fri, 24 Dec 2021 21:43:24 UTC via https://ntfy.sh/alerts`
+	require.Equal(t, expected, actual)
+}

server/server.go

@@ -3,7 +3,7 @@ package server
 import (
 	"bytes"
 	"context"
-	"embed" // required for go:embed
+	"embed"
 	"encoding/json"
 	firebase "firebase.google.com/go"
 	"firebase.google.com/go/messaging"
@@ -33,6 +33,7 @@ type Server struct {
 	topics      map[string]*topic
 	visitors    map[string]*visitor
 	firebase    subscriber
+	mailer      mailer
 	messages    int64
 	cache       cache
 	closeChan   chan bool
@@ -110,6 +111,7 @@ var (
 
 const (
 	firebaseControlTopic = "~control" // See Android if changed
+	emptyMessageBody     = "triggered"
 )
 
 // New instantiates a new Server. It creates the cache and adds a Firebase
@@ -123,6 +125,10 @@ func New(conf *Config) (*Server, error) {
 			return nil, err
 		}
 	}
+	var mailer mailer
+	if conf.SMTPAddr != "" {
+		mailer = &smtpMailer{config: conf}
+	}
 	cache, err := createCache(conf)
 	if err != nil {
 		return nil, err
@@ -135,6 +141,7 @@ func New(conf *Config) (*Server, error) {
 		config:   conf,
 		cache:    cache,
 		firebase: firebaseSubscriber,
+		mailer:   mailer,
 		topics:   topics,
 		visitors: make(map[string]*visitor),
 	}, nil
@@ -296,7 +303,7 @@ func (s *Server) handleDocs(w http.ResponseWriter, r *http.Request) error {
 	return nil
 }
 
-func (s *Server) handlePublish(w http.ResponseWriter, r *http.Request, _ *visitor) error {
+func (s *Server) handlePublish(w http.ResponseWriter, r *http.Request, v *visitor) error {
 	t, err := s.topicFromPath(r.URL.Path)
 	if err != nil {
 		return err
@@ -307,12 +314,20 @@ func (s *Server) handlePublish(w http.ResponseWriter, r *http.Request, _ *visito
 		return err
 	}
 	m := newDefaultMessage(t.ID, strings.TrimSpace(string(b)))
-	cache, firebase, err := s.parseParams(r, m)
+	cache, firebase, email, err := s.parseParams(r, m)
 	if err != nil {
 		return err
 	}
+	if email != "" {
+		if err := v.EmailAllowed(); err != nil {
+			return err
+		}
+	}
+	if s.mailer == nil && email != "" {
+		return errHTTPBadRequest
+	}
 	if m.Message == "" {
-		m.Message = "triggered"
+		m.Message = emptyMessageBody
 	}
 	delayed := m.Time > time.Now().Unix()
 	if !delayed {
@@ -327,6 +342,13 @@ func (s *Server) handlePublish(w http.ResponseWriter, r *http.Request, _ *visito
 			}
 		}()
 	}
+	if s.mailer != nil && email != "" && !delayed {
+		go func() {
+			if err := s.mailer.Send(v.ip, email, m); err != nil {
+				log.Printf("Unable to send email: %v", err.Error())
+			}
+		}()
+	}
 	if cache {
 		if err := s.cache.AddMessage(m); err != nil {
 			return err
@@ -341,9 +363,10 @@ func (s *Server) handlePublish(w http.ResponseWriter, r *http.Request, _ *visito
 	return nil
 }
 
-func (s *Server) parseParams(r *http.Request, m *message) (cache bool, firebase bool, err error) {
+func (s *Server) parseParams(r *http.Request, m *message) (cache bool, firebase bool, email string, err error) {
 	cache = readParam(r, "x-cache", "cache") != "no"
 	firebase = readParam(r, "x-firebase", "firebase") != "no"
+	email = readParam(r, "x-email", "x-e-mail", "email", "e-mail", "mail", "e")
 	m.Title = readParam(r, "x-title", "title", "t")
 	messageStr := readParam(r, "x-message", "message", "m")
 	if messageStr != "" {
@@ -351,7 +374,7 @@ func (s *Server) parseParams(r *http.Request, m *message) (cache bool, firebase
 	}
 	m.Priority, err = util.ParsePriority(readParam(r, "x-priority", "priority", "prio", "p"))
 	if err != nil {
-		return false, false, errHTTPBadRequest
+		return false, false, "", errHTTPBadRequest
 	}
 	tagsStr := readParam(r, "x-tags", "tags", "tag", "ta")
 	if tagsStr != "" {
@@ -363,19 +386,22 @@ func (s *Server) parseParams(r *http.Request, m *message) (cache bool, firebase
 	delayStr := readParam(r, "x-delay", "delay", "x-at", "at", "x-in", "in")
 	if delayStr != "" {
 		if !cache {
-			return false, false, errHTTPBadRequest
+			return false, false, "", errHTTPBadRequest
+		}
+		if email != "" {
+			return false, false, "", errHTTPBadRequest // we cannot store the email address (yet)
 		}
 		delay, err := util.ParseFutureTime(delayStr, time.Now())
 		if err != nil {
-			return false, false, errHTTPBadRequest
+			return false, false, "", errHTTPBadRequest
 		} else if delay.Unix() < time.Now().Add(s.config.MinDelay).Unix() {
-			return false, false, errHTTPBadRequest
+			return false, false, "", errHTTPBadRequest
 		} else if delay.Unix() > time.Now().Add(s.config.MaxDelay).Unix() {
-			return false, false, errHTTPBadRequest
+			return false, false, "", errHTTPBadRequest
 		}
 		m.Time = delay.Unix()
 	}
-	return cache, firebase, nil
+	return cache, firebase, email, nil
 }
 
 func readParam(r *http.Request, names ...string) string {
@@ -714,6 +740,7 @@ func (s *Server) sendDelayedMessages() error {
 					log.Printf("unable to publish to Firebase: %v", err.Error())
 				}
 			}
+			// TODO delayed email sending
 		}
 		if err := s.cache.MarkPublished(m); err != nil {
 			return err
@@ -745,7 +772,7 @@ func (s *Server) visitor(r *http.Request) *visitor {
 	}
 	v, exists := s.visitors[ip]
 	if !exists {
-		s.visitors[ip] = newVisitor(s.config)
+		s.visitors[ip] = newVisitor(s.config, ip)
 		return s.visitors[ip]
 	}
 	v.Keepalive()

server/server.yml

@@ -1,8 +1,12 @@
 # ntfy server config file
 
+# Public facing base URL of the service (e.g. https://ntfy.sh or https://ntfy.example.com)
+# This setting is currently only used by the e-mail feature.
+#
+# base-url:
+
 # Listen address for the HTTP & HTTPS web server. If "listen-https" is set, you must also
-# set "key-file" and "cert-file".
+# set "key-file" and "cert-file". Format: <hostname>:<port>
-# Format: <hostname>:<port>
 #
 # listen-http: ":80"
 # listen-https:
@@ -34,6 +38,27 @@
 #
 # cache-duration: 12h
 
+# If set, the X-Forwarded-For header is used to determine the visitor IP address
+# instead of the remote address of the connection.
+#
+# WARNING: If you are behind a proxy, you must set this, otherwise all visitors are rate limited
+#          as if they are one.
+#
+# behind-proxy: false
+
+# If enabled, allow e-mail notifications via the 'X-Email' header. As of today, only SMTP servers
+# with plain text auth and STARTLS are supported. Please also refer to the rate limiting settings
+# below (visitor-email-limit-burst & visitor-email-limit-burst).
+#
+# - smtp-addr is the hostname:port of the SMTP server
+# - smtp-user/smtp-pass are the username and password of the SMTP user
+# - smtp-from is the e-mail address of the sender
+#
+# smtp-addr:
+# smtp-user:
+# smtp-pass:
+# smtp-from:
+
 # Interval in which keepalive messages are sent to the client. This is to prevent
 # intermediaries closing the connection for inactivity.
 #
@@ -61,10 +86,9 @@
 # visitor-request-limit-burst: 60
 # visitor-request-limit-replenish: 10s
 
-# If set, the X-Forwarded-For header is used to determine the visitor IP address
+# Rate limiting: Allowed emails per visitor:
-# instead of the remote address of the connection.
+# - visitor-email-limit-burst is the initial bucket of emails each visitor has
+# - visitor-email-limit-replenish is the rate at which the bucket is refilled
 #
-# WARNING: If you are behind a proxy, you must set this, otherwise all visitors are rate limited
+# visitor-email-limit-burst: 16
-#          as if they are one.
+# visitor-email-limit-replenish: 1h
-#
-# behind-proxy: false

server/server_test.go

@@ -11,6 +11,7 @@ import (
 	"os"
 	"path/filepath"
 	"strings"
+	"sync"
 	"testing"
 	"time"
 )
@@ -508,6 +509,79 @@ func TestServer_Curl_Publish_Poll(t *testing.T) {
 }
 */
 
+type testMailer struct {
+	count int
+	mu    sync.Mutex
+}
+
+func (t *testMailer) Send(from, to string, m *message) error {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	t.count++
+	return nil
+}
+
+func TestServer_PublishTooManyEmails_Defaults(t *testing.T) {
+	s := newTestServer(t, newTestConfig(t))
+	s.mailer = &testMailer{}
+	for i := 0; i < 16; i++ {
+		response := request(t, s, "PUT", "/mytopic", fmt.Sprintf("message %d", i), map[string]string{
+			"E-Mail": "test@example.com",
+		})
+		require.Equal(t, 200, response.Code)
+	}
+	response := request(t, s, "PUT", "/mytopic", "one too many", map[string]string{
+		"E-Mail": "test@example.com",
+	})
+	require.Equal(t, 429, response.Code)
+}
+
+func TestServer_PublishTooManyEmails_Replenish(t *testing.T) {
+	c := newTestConfig(t)
+	c.VisitorEmailLimitReplenish = 500 * time.Millisecond
+	s := newTestServer(t, c)
+	s.mailer = &testMailer{}
+	for i := 0; i < 16; i++ {
+		response := request(t, s, "PUT", "/mytopic", fmt.Sprintf("message %d", i), map[string]string{
+			"E-Mail": "test@example.com",
+		})
+		require.Equal(t, 200, response.Code)
+	}
+	response := request(t, s, "PUT", "/mytopic", "one too many", map[string]string{
+		"E-Mail": "test@example.com",
+	})
+	require.Equal(t, 429, response.Code)
+
+	time.Sleep(510 * time.Millisecond)
+	response = request(t, s, "PUT", "/mytopic", "this should be okay again too many", map[string]string{
+		"E-Mail": "test@example.com",
+	})
+	require.Equal(t, 200, response.Code)
+
+	response = request(t, s, "PUT", "/mytopic", "and bad again", map[string]string{
+		"E-Mail": "test@example.com",
+	})
+	require.Equal(t, 429, response.Code)
+}
+
+func TestServer_PublishDelayedEmail_Fail(t *testing.T) {
+	s := newTestServer(t, newTestConfig(t))
+	s.mailer = &testMailer{}
+	response := request(t, s, "PUT", "/mytopic", "fail", map[string]string{
+		"E-Mail": "test@example.com",
+		"Delay":  "20 min",
+	})
+	require.Equal(t, 400, response.Code)
+}
+
+func TestServer_PublishEmailNoMailer_Fail(t *testing.T) {
+	s := newTestServer(t, newTestConfig(t))
+	response := request(t, s, "PUT", "/mytopic", "fail", map[string]string{
+		"E-Mail": "test@example.com",
+	})
+	require.Equal(t, 400, response.Code)
+}
+
 func newTestConfig(t *testing.T) *Config {
 	conf := NewConfig()
 	conf.CacheFile = filepath.Join(t.TempDir(), "cache.db")

server/visitor.go

@@ -8,29 +8,47 @@ import (
 )
 
 const (
-	visitorExpungeAfter = 30 * time.Minute
+	// visitorExpungeAfter defines how long a visitor is active before it is removed from memory. This number
+	// has to be very high to prevent e-mail abuse, but it doesn't really affect the other limits anyway, since
+	// they are replenished faster (typically).
+	visitorExpungeAfter = 24 * time.Hour
 )
 
 // visitor represents an API user, and its associated rate.Limiter used for rate limiting
 type visitor struct {
 	config        *Config
-	limiter       *rate.Limiter
+	ip            string
+	requests      *rate.Limiter
+	emails        *rate.Limiter
 	subscriptions *util.Limiter
 	seen          time.Time
 	mu            sync.Mutex
 }
 
-func newVisitor(conf *Config) *visitor {
+func newVisitor(conf *Config, ip string) *visitor {
 	return &visitor{
 		config:        conf,
-		limiter:       rate.NewLimiter(rate.Every(conf.VisitorRequestLimitReplenish), conf.VisitorRequestLimitBurst),
+		ip:            ip,
+		requests:      rate.NewLimiter(rate.Every(conf.VisitorRequestLimitReplenish), conf.VisitorRequestLimitBurst),
+		emails:        rate.NewLimiter(rate.Every(conf.VisitorEmailLimitReplenish), conf.VisitorEmailLimitBurst),
 		subscriptions: util.NewLimiter(int64(conf.VisitorSubscriptionLimit)),
 		seen:          time.Now(),
 	}
 }
 
+func (v *visitor) IP() string {
+	return v.ip
+}
+
 func (v *visitor) RequestAllowed() error {
-	if !v.limiter.Allow() {
+	if !v.requests.Allow() {
+		return errHTTPTooManyRequests
+	}
+	return nil
+}
+
+func (v *visitor) EmailAllowed() error {
+	if !v.emails.Allow() {
 		return errHTTPTooManyRequests
 	}
 	return nil

test/server.go

@@ -10,13 +10,17 @@ import (
 )
 
 func init() {
-	rand.Seed(time.Now().Unix())
+	rand.Seed(time.Now().UnixMilli())
 }
 
 // StartServer starts a server.Server with a random port and waits for the server to be up
 func StartServer(t *testing.T) (*server.Server, int) {
+	return StartServerWithConfig(t, server.NewConfig())
+}
+
+// StartServerWithConfig starts a server.Server with a random port and waits for the server to be up
+func StartServerWithConfig(t *testing.T, conf *server.Config) (*server.Server, int) {
 	port := 10000 + rand.Intn(20000)
-	conf := server.NewConfig()
 	conf.ListenHTTP = fmt.Sprintf(":%d", port)
 	s, err := server.New(conf)
 	if err != nil {

util/util.go

@@ -134,7 +134,32 @@ func ParsePriority(priority string) (int, error) {
 	}
 }
 
+// PriorityString converts a priority number to a string
+func PriorityString(priority int) (string, error) {
+	switch priority {
+	case 0:
+		return "default", nil
+	case 1:
+		return "min", nil
+	case 2:
+		return "low", nil
+	case 3:
+		return "default", nil
+	case 4:
+		return "high", nil
+	case 5:
+		return "max", nil
+	default:
+		return "", errInvalidPriority
+	}
+}
+
 // ExpandHome replaces "~" with the user's home directory
 func ExpandHome(path string) string {
 	return os.ExpandEnv(strings.ReplaceAll(path, "~", "$HOME"))
 }
+
+// ShortTopicURL shortens the topic URL to be human-friendly, removing the http:// or https://
+func ShortTopicURL(s string) string {
+	return strings.TrimPrefix(strings.TrimPrefix(s, "https://"), "http://")
+}

util/util_test.go

@@ -100,3 +100,24 @@ func TestParsePriority_Invalid(t *testing.T) {
 		require.Equal(t, errInvalidPriority, err)
 	}
 }
+
+func TestPriorityString(t *testing.T) {
+	priorities := []int{0, 1, 2, 3, 4, 5}
+	expected := []string{"default", "min", "low", "default", "high", "max"}
+	for i, priority := range priorities {
+		actual, err := PriorityString(priority)
+		require.Nil(t, err)
+		require.Equal(t, expected[i], actual)
+	}
+}
+
+func TestPriorityString_Invalid(t *testing.T) {
+	_, err := PriorityString(99)
+	require.Equal(t, err, errInvalidPriority)
+}
+
+func TestShortTopicURL(t *testing.T) {
+	require.Equal(t, "ntfy.sh/mytopic", ShortTopicURL("https://ntfy.sh/mytopic"))
+	require.Equal(t, "ntfy.sh/mytopic", ShortTopicURL("http://ntfy.sh/mytopic"))
+	require.Equal(t, "lalala", ShortTopicURL("lalala"))
+}