fix(notifications): title customization (#1219)

docs/notifications.md

@@ -28,6 +28,8 @@ comma-separated list of values to the `--notifications` option
 -   `--notifications-hostname` (env. `WATCHTOWER_NOTIFICATIONS_HOSTNAME`): Custom hostname specified in subject/title. Useful to override the operating system hostname.
 -   `--notifications-delay` (env. `WATCHTOWER_NOTIFICATION_DELAY`): Delay before sending notifications expressed in seconds.
 -   Watchtower will post a notification every time it is started. This behavior [can be changed](https://containrrr.github.io/watchtower/arguments/#without_sending_a_startup_message) with an argument.
+-   `notification-title-tag` (env. `WATCHTOWER_NOTIFICATION_TITLE_TAG`): Prefix to include in the title. Useful when running multiple watchtowers.
+-   `notification-skip-title` (env. `WATCHTOWER_NOTIFICATION_SKIP_TITLE`): Do not pass the title param to notifications. This will not pass a dynamic title override to notification services. If no title is configured for the service, it will remove the title all together.
 
 ## Available services
 
@@ -43,7 +45,7 @@ To receive notifications by email, the following command-line options, or their
 -   `--notification-email-server-user` (env. `WATCHTOWER_NOTIFICATION_EMAIL_SERVER_USER`): The username to authenticate with the SMTP server with.
 -   `--notification-email-server-password` (env. `WATCHTOWER_NOTIFICATION_EMAIL_SERVER_PASSWORD`): The password to authenticate with the SMTP server with. Can also reference a file, in which case the contents of the file are used.
 -   `--notification-email-delay` (env. `WATCHTOWER_NOTIFICATION_EMAIL_DELAY`): Delay before sending notifications expressed in seconds.
--   `--notification-email-subjecttag` (env. `WATCHTOWER_NOTIFICATION_EMAIL_SUBJECTTAG`): Prefix to include in the subject tag. Useful when running multiple watchtowers.
+-   `--notification-email-subjecttag` (env. `WATCHTOWER_NOTIFICATION_EMAIL_SUBJECTTAG`): Prefix to include in the subject tag. Useful when running multiple watchtowers. **NOTE:** This will affect all notification types.
 
 Example:
 

internal/flags/flags.go

@@ -326,6 +326,16 @@ Should only be used for testing.`)
 		viper.GetBool("WATCHTOWER_NOTIFICATION_REPORT"),
 		"Use the session report as the notification template data")
 
+	flags.StringP(
+		"notification-title-tag",
+		"",
+		viper.GetString("WATCHTOWER_NOTIFICATION_TITLE_TAG"),
+		"Title prefix tag for notifications")
+
+	flags.Bool("notification-skip-title",
+		viper.GetBool("WATCHTOWER_NOTIFICATION_SKIP_TITLE"),
+		"Do not pass the title param to notifications")
+
 	flags.String(
 		"warn-on-head-failure",
 		viper.GetString("WATCHTOWER_WARN_ON_HEAD_FAILURE"),

pkg/notifications/notifier.go

@@ -2,6 +2,7 @@ package notifications
 
 import (
 	"os"
+	"strings"
 	"time"
 
 	ty "github.com/containrrr/watchtower/pkg/types"
@@ -30,10 +31,10 @@ func NewNotifier(c *cobra.Command) ty.Notifier {
 	tplString, _ := f.GetString("notification-template")
 	urls, _ := f.GetStringArray("notification-url")
 
-	hostname := GetHostname(c)
-	urls, delay := AppendLegacyUrls(urls, c, GetTitle(hostname))
+	data := GetTemplateData(c)
+	urls, delay := AppendLegacyUrls(urls, c, data.Title)
 
-	return newShoutrrrNotifier(tplString, acceptedLogLevels, !reportTemplate, hostname, delay, urls...)
+	return newShoutrrrNotifier(tplString, acceptedLogLevels, !reportTemplate, data, delay, urls...)
 }
 
 // AppendLegacyUrls creates shoutrrr equivalent URLs from legacy notification flags
@@ -99,28 +100,50 @@ func GetDelay(c *cobra.Command, legacyDelay time.Duration) time.Duration {
 	return time.Duration(0)
 }
 
-// GetTitle returns a common notification title with hostname appended
-func GetTitle(hostname string) string {
-	title := "Watchtower updates"
+// GetTitle formats the title based on the passed hostname and tag
+func GetTitle(hostname string, tag string) string {
+	tb := strings.Builder{}
+
+	if tag != "" {
+		tb.WriteRune('[')
+		tb.WriteString(tag)
+		tb.WriteRune(']')
+		tb.WriteRune(' ')
+	}
+
+	tb.WriteString("Watchtower updates")
+
 	if hostname != "" {
-		title += " on " + hostname
+		tb.WriteString(" on ")
+		tb.WriteString(hostname)
 	}
-	return title
-}
 
-// GetHostname returns the hostname as set by args or resolved from OS
-func GetHostname(c *cobra.Command) string {
+	return tb.String()
+}
 
+// GetTemplateData populates the static notification data from flags and environment
+func GetTemplateData(c *cobra.Command) StaticData {
 	f := c.PersistentFlags()
+
 	hostname, _ := f.GetString("notifications-hostname")
+	if hostname == "" {
+		hostname, _ = os.Hostname()
+	}
 
-	if hostname != "" {
-		return hostname
-	} else if hostname, err := os.Hostname(); err == nil {
-		return hostname
+	title := ""
+	if skip, _ := f.GetBool("notification-skip-title"); !skip {
+		tag, _ := f.GetString("notification-title-tag")
+		if tag == "" {
+			// For legacy email support
+			tag, _ = f.GetString("notification-email-subjecttag")
+		}
+		title = GetTitle(hostname, tag)
 	}
 
-	return ""
+	return StaticData{
+		Host:  hostname,
+		Title: title,
+	}
 }
 
 // ColorHex is the default notification color used for services that support it (formatted as a CSS hex string)

pkg/notifications/notifier_test.go

@@ -39,17 +39,58 @@ var _ = Describe("notifications", func() {
 					"test.host",
 				})
 				Expect(err).NotTo(HaveOccurred())
-				hostname := notifications.GetHostname(command)
-				title := notifications.GetTitle(hostname)
+				data := notifications.GetTemplateData(command)
+				title := data.Title
 				Expect(title).To(Equal("Watchtower updates on test.host"))
 			})
 		})
 		When("no hostname can be resolved", func() {
 			It("should use the default simple title", func() {
-				title := notifications.GetTitle("")
+				title := notifications.GetTitle("", "")
 				Expect(title).To(Equal("Watchtower updates"))
 			})
 		})
+		When("title tag is set", func() {
+			It("should use the prefix in the title", func() {
+				command := cmd.NewRootCommand()
+				flags.RegisterNotificationFlags(command)
+
+				Expect(command.ParseFlags([]string{
+					"--notification-title-tag",
+					"PREFIX",
+				})).To(Succeed())
+
+				data := notifications.GetTemplateData(command)
+				Expect(data.Title).To(HavePrefix("[PREFIX]"))
+			})
+		})
+		When("legacy email tag is set", func() {
+			It("should use the prefix in the title", func() {
+				command := cmd.NewRootCommand()
+				flags.RegisterNotificationFlags(command)
+
+				Expect(command.ParseFlags([]string{
+					"--notification-email-subjecttag",
+					"PREFIX",
+				})).To(Succeed())
+
+				data := notifications.GetTemplateData(command)
+				Expect(data.Title).To(HavePrefix("[PREFIX]"))
+			})
+		})
+		When("the skip title flag is set", func() {
+			It("should return an empty title", func() {
+				command := cmd.NewRootCommand()
+				flags.RegisterNotificationFlags(command)
+
+				Expect(command.ParseFlags([]string{
+					"--notification-skip-title",
+				})).To(Succeed())
+
+				data := notifications.GetTemplateData(command)
+				Expect(data.Title).To(BeEmpty())
+			})
+		})
 		When("no delay is defined", func() {
 			It("should use the default delay", func() {
 				command := cmd.NewRootCommand()
@@ -106,8 +147,8 @@ var _ = Describe("notifications", func() {
 			channel := "123456789"
 			token := "abvsihdbau"
 			color := notifications.ColorInt
-			hostname := notifications.GetHostname(command)
-			title := url.QueryEscape(notifications.GetTitle(hostname))
+			data := notifications.GetTemplateData(command)
+			title := url.QueryEscape(data.Title)
 			expected := fmt.Sprintf("discord://%s@%s?color=0x%x&colordebug=0x0&colorerror=0x0&colorinfo=0x0&colorwarn=0x0&title=%s&username=watchtower", token, channel, color, title)
 			buildArgs := func(url string) []string {
 				return []string{
@@ -135,8 +176,8 @@ var _ = Describe("notifications", func() {
 			tokenB := "BBBBBBBBB"
 			tokenC := "123456789123456789123456"
 			color := url.QueryEscape(notifications.ColorHex)
-			hostname := notifications.GetHostname(command)
-			title := url.QueryEscape(notifications.GetTitle(hostname))
+			data := notifications.GetTemplateData(command)
+			title := url.QueryEscape(data.Title)
 			iconURL := "https://containrrr.dev/watchtower-sq180.png"
 			iconEmoji := "whale"
 
@@ -194,8 +235,8 @@ var _ = Describe("notifications", func() {
 
 				token := "aaa"
 				host := "shoutrrr.local"
-				hostname := notifications.GetHostname(command)
-				title := url.QueryEscape(notifications.GetTitle(hostname))
+				data := notifications.GetTemplateData(command)
+				title := url.QueryEscape(data.Title)
 
 				expectedOutput := fmt.Sprintf("gotify://%s/%s?title=%s", host, token, title)
 
@@ -223,8 +264,8 @@ var _ = Describe("notifications", func() {
 				tokenB := "33333333012222222222333333333344"
 				tokenC := "44444444-4444-4444-8444-cccccccccccc"
 				color := url.QueryEscape(notifications.ColorHex)
-				hostname := notifications.GetHostname(command)
-				title := url.QueryEscape(notifications.GetTitle(hostname))
+				data := notifications.GetTemplateData(command)
+				title := url.QueryEscape(data.Title)
 
 				hookURL := fmt.Sprintf("https://outlook.office.com/webhook/%s/IncomingWebhook/%s/%s", tokenA, tokenB, tokenC)
 				expectedOutput := fmt.Sprintf("teams://%s/%s/%s?color=%s&title=%s", tokenA, tokenB, tokenC, color, title)
@@ -319,14 +360,10 @@ func testURL(args []string, expectedURL string, expectedDelay time.Duration) {
 	command := cmd.NewRootCommand()
 	flags.RegisterNotificationFlags(command)
 
-	err := command.ParseFlags(args)
-	Expect(err).NotTo(HaveOccurred())
+	Expect(command.ParseFlags(args)).To(Succeed())
 
-	hostname := notifications.GetHostname(command)
-	title := notifications.GetTitle(hostname)
-	urls, delay := notifications.AppendLegacyUrls([]string{}, command, title)
-
-	Expect(err).NotTo(HaveOccurred())
+	data := notifications.GetTemplateData(command)
+	urls, delay := notifications.AppendLegacyUrls([]string{}, command, data.Title)
 
 	Expect(urls).To(ContainElement(expectedURL))
 	Expect(delay).To(Equal(expectedDelay))

pkg/notifications/shoutrrr.go

@@ -58,7 +58,7 @@ type shoutrrrTypeNotifier struct {
 	done           chan bool
 	legacyTemplate bool
 	params         *types.Params
-	hostname       string
+	data           StaticData
 }
 
 // GetScheme returns the scheme part of a Shoutrrr URL
@@ -79,11 +79,9 @@ func (n *shoutrrrTypeNotifier) GetNames() []string {
 	return names
 }
 
-func newShoutrrrNotifier(tplString string, acceptedLogLevels []log.Level, legacy bool, hostname string, delay time.Duration, urls ...string) t.Notifier {
+func newShoutrrrNotifier(tplString string, acceptedLogLevels []log.Level, legacy bool, data StaticData, delay time.Duration, urls ...string) t.Notifier {
 
-	notifier := createNotifier(urls, acceptedLogLevels, tplString, legacy)
-	notifier.hostname = hostname
-	notifier.params = &types.Params{"title": GetTitle(hostname)}
+	notifier := createNotifier(urls, acceptedLogLevels, tplString, legacy, data)
 	log.AddHook(notifier)
 
 	// Do the sending in a separate goroutine so we don't block the main process.
@@ -92,7 +90,7 @@ func newShoutrrrNotifier(tplString string, acceptedLogLevels []log.Level, legacy
 	return notifier
 }
 
-func createNotifier(urls []string, levels []log.Level, tplString string, legacy bool) *shoutrrrTypeNotifier {
+func createNotifier(urls []string, levels []log.Level, tplString string, legacy bool, data StaticData) *shoutrrrTypeNotifier {
 	tpl, err := getShoutrrrTemplate(tplString, legacy)
 	if err != nil {
 		log.Errorf("Could not use configured notification template: %s. Using default template", err)
@@ -104,6 +102,11 @@ func createNotifier(urls []string, levels []log.Level, tplString string, legacy
 		log.Fatalf("Failed to initialize Shoutrrr notifications: %s\n", err.Error())
 	}
 
+	params := &types.Params{}
+	if data.Title != "" {
+		params.SetTitle(data.Title)
+	}
+
 	return &shoutrrrTypeNotifier{
 		Urls:           urls,
 		Router:         r,
@@ -112,6 +115,8 @@ func createNotifier(urls []string, levels []log.Level, tplString string, legacy
 		logLevels:      levels,
 		template:       tpl,
 		legacyTemplate: legacy,
+		data:           data,
+		params:         params,
 	}
 }
 
@@ -149,9 +154,7 @@ func (n *shoutrrrTypeNotifier) buildMessage(data Data) (string, error) {
 }
 
 func (n *shoutrrrTypeNotifier) sendEntries(entries []*log.Entry, report t.Report) {
-	title, _ := n.params.Title()
-	host := n.hostname
-	msg, err := n.buildMessage(Data{entries, report, title, host})
+	msg, err := n.buildMessage(Data{n.data, entries, report})
 
 	if msg == "" {
 		// Log in go func in case we entered from Fire to avoid stalling
@@ -240,10 +243,15 @@ func getShoutrrrTemplate(tplString string, legacy bool) (tpl *template.Template,
 	return
 }
 
+// StaticData is the part of the notification template data model set upon initialization
+type StaticData struct {
+	Title string
+	Host  string
+}
+
 // Data is the notification template data model
 type Data struct {
+	StaticData
 	Entries []*log.Entry
 	Report  t.Report
-	Title   string
-	Host    string
 }

pkg/notifications/shoutrrr_test.go

@@ -49,11 +49,14 @@ var mockDataAllFresh = Data{
 
 func mockDataFromStates(states ...s.State) Data {
 	hostname := "Mock"
+	prefix := ""
 	return Data{
 		Entries: legacyMockData.Entries,
 		Report:  mocks.CreateMockProgressReport(states...),
-		Title:   GetTitle(hostname),
-		Host:    hostname,
+		StaticData: StaticData{
+			Title: GetTitle(hostname, prefix),
+			Host:  hostname,
+		},
 	}
 }
 
@@ -77,7 +80,7 @@ var _ = Describe("Shoutrrr", func() {
 				cmd := new(cobra.Command)
 				flags.RegisterNotificationFlags(cmd)
 
-				shoutrrr := createNotifier([]string{}, logrus.AllLevels, "", true)
+				shoutrrr := createNotifier([]string{}, logrus.AllLevels, "", true, StaticData{})
 
 				entries := []*logrus.Entry{
 					{
@@ -233,7 +236,7 @@ Turns out everything is on fire
 	When("batching notifications", func() {
 		When("no messages are queued", func() {
 			It("should not send any notification", func() {
-				shoutrrr := newShoutrrrNotifier("", allButTrace, true, "", time.Duration(0), "logger://")
+				shoutrrr := newShoutrrrNotifier("", allButTrace, true, StaticData{}, time.Duration(0), "logger://")
 				shoutrrr.StartNotification()
 				shoutrrr.SendNotification(nil)
 				Consistently(logBuffer).ShouldNot(gbytes.Say(`Shoutrrr:`))
@@ -241,7 +244,7 @@ Turns out everything is on fire
 		})
 		When("at least one message is queued", func() {
 			It("should send a notification", func() {
-				shoutrrr := newShoutrrrNotifier("", allButTrace, true, "", time.Duration(0), "logger://")
+				shoutrrr := newShoutrrrNotifier("", allButTrace, true, StaticData{}, time.Duration(0), "logger://")
 				shoutrrr.StartNotification()
 				logrus.Info("This log message is sponsored by ContainrrrVPN")
 				shoutrrr.SendNotification(nil)
@@ -250,6 +253,17 @@ Turns out everything is on fire
 		})
 	})
 
+	When("the title data field is empty", func() {
+		It("should not have set the title param", func() {
+			shoutrrr := createNotifier([]string{"logger://"}, allButTrace, "", true, StaticData{
+				Host:  "test.host",
+				Title: "",
+			})
+			_, found := shoutrrr.params.Title()
+			Expect(found).ToNot(BeTrue())
+		})
+	})
+
 	When("sending notifications", func() {
 
 		It("SlowNotificationNotSent", func() {