refactor(updater): smart message generation (part 3 of shoutrrr suppo…

…rt) (#762)

cmd/ddns/ddns.go

@@ -55,11 +55,8 @@ func initConfig(ctx context.Context, ppfmt pp.PP) (*config.Config, setter.Setter
 
 func stopUpdating(ctx context.Context, ppfmt pp.PP, c *config.Config, s setter.Setter) {
 	if c.DeleteOnStop {
-		if ok, msg := updater.DeleteIPs(ctx, ppfmt, c, s); ok {
-			monitor.LogAll(ctx, ppfmt, msg, c.Monitors)
-		} else {
-			monitor.FailureAll(ctx, ppfmt, msg, c.Monitors)
-		}
+		resp := updater.DeleteIPs(ctx, ppfmt, c, s)
+		monitor.SendAll(ctx, ppfmt, c.Monitors, resp)
 	}
 }
 
@@ -94,10 +91,10 @@ func realMain() int { //nolint:funlen
 	// Read the config and get the handler and the setter
 	c, s, configOk := initConfig(ctx, ppfmt)
 	// Ping the monitor regardless of whether initConfig succeeded
-	monitor.StartAll(ctx, ppfmt, formatName(), c.Monitors)
+	monitor.StartAll(ctx, ppfmt, c.Monitors, formatName())
 	// Bail out now if initConfig failed
 	if !configOk {
-		monitor.ExitStatusAll(ctx, ppfmt, 1, "Config errors", c.Monitors)
+		monitor.ExitStatusAll(ctx, ppfmt, c.Monitors, 1, "Config errors")
 		ppfmt.Infof(pp.EmojiBye, "Bye!")
 		return 1
 	}
@@ -121,13 +118,10 @@ func realMain() int { //nolint:funlen
 
 		// Update the IP addresses
 		if first && !c.UpdateOnStart {
-			monitor.SuccessAll(ctx, ppfmt, "Started (no action)", c.Monitors)
+			monitor.SuccessAll(ctx, ppfmt, c.Monitors, "Started (no action)")
 		} else {
-			if ok, msg := updater.UpdateIPs(ctxWithSignals, ppfmt, c, s); ok {
-				monitor.SuccessAll(ctx, ppfmt, msg, c.Monitors)
-			} else {
-				monitor.FailureAll(ctx, ppfmt, msg, c.Monitors)
-			}
+			resp := updater.UpdateIPs(ctxWithSignals, ppfmt, c, s)
+			monitor.SendAll(ctx, ppfmt, c.Monitors, resp)
 		}
 
 		// Check if cron was disabled
@@ -142,7 +136,7 @@ func realMain() int { //nolint:funlen
 		if next.IsZero() {
 			ppfmt.Errorf(pp.EmojiUserError, "No scheduled updates in near future")
 			stopUpdating(ctx, ppfmt, c, s)
-			monitor.ExitStatusAll(ctx, ppfmt, 1, "No scheduled updates", c.Monitors)
+			monitor.ExitStatusAll(ctx, ppfmt, c.Monitors, 1, "No scheduled updates")
 			ppfmt.Infof(pp.EmojiBye, "Bye!")
 			return 1
 		}
@@ -153,7 +147,7 @@ func realMain() int { //nolint:funlen
 		// Wait for the next signal or the alarm, whichever comes first
 		if !sig.SleepUntil(ppfmt, next) {
 			stopUpdating(ctx, ppfmt, c, s)
-			monitor.ExitStatusAll(ctx, ppfmt, 0, "Terminated", c.Monitors)
+			monitor.ExitStatusAll(ctx, ppfmt, c.Monitors, 0, "Terminated")
 			ppfmt.Infof(pp.EmojiBye, "Bye!")
 			return 0
 		}

internal/monitor/base.go

@@ -3,8 +3,10 @@ package monitor
 
 import (
 	"context"
+	"strings"
 
 	"github.com/favonia/cloudflare-ddns/internal/pp"
+	"github.com/favonia/cloudflare-ddns/internal/response"
 )
 
 //go:generate mockgen -typed -destination=../mocks/mock_monitor.go -package=mocks . Monitor
@@ -33,3 +35,12 @@ type Monitor interface {
 	// ExitStatus records the exit status (as an integer in the POSIX style).
 	ExitStatus(ctx context.Context, ppfmt pp.PP, code int, message string) bool
 }
+
+func Send(ctx context.Context, ppfmt pp.PP, m Monitor, r response.Response) bool {
+	msg := strings.Join(r.MonitorMessages, "\n")
+	if r.Ok {
+		return m.Log(ctx, ppfmt, msg)
+	} else {
+		return m.Failure(ctx, ppfmt, msg)
+	}
+}

internal/monitor/composite.go

@@ -4,6 +4,7 @@ import (
 	"context"
 
 	"github.com/favonia/cloudflare-ddns/internal/pp"
+	"github.com/favonia/cloudflare-ddns/internal/response"
 )
 
 // DescribeAll calls [Monitor.Describe] for each monitor in the group with the callback.
@@ -14,7 +15,7 @@ func DescribeAll(callback func(service, params string), ms []Monitor) {
 }
 
 // SuccessAll calls [Monitor.Success] for each monitor in the group.
-func SuccessAll(ctx context.Context, ppfmt pp.PP, message string, ms []Monitor) bool {
+func SuccessAll(ctx context.Context, ppfmt pp.PP, ms []Monitor, message string) bool {
 	ok := true
 	for _, m := range ms {
 		if !m.Success(ctx, ppfmt, message) {
@@ -25,7 +26,7 @@ func SuccessAll(ctx context.Context, ppfmt pp.PP, message string, ms []Monitor)
 }
 
 // StartAll calls [Monitor.Start] for each monitor in ms.
-func StartAll(ctx context.Context, ppfmt pp.PP, message string, ms []Monitor) bool {
+func StartAll(ctx context.Context, ppfmt pp.PP, ms []Monitor, message string) bool {
 	ok := true
 	for _, m := range ms {
 		if !m.Start(ctx, ppfmt, message) {
@@ -36,7 +37,7 @@ func StartAll(ctx context.Context, ppfmt pp.PP, message string, ms []Monitor) bo
 }
 
 // FailureAll calls [Monitor.Failure] for each monitor in ms.
-func FailureAll(ctx context.Context, ppfmt pp.PP, message string, ms []Monitor) bool {
+func FailureAll(ctx context.Context, ppfmt pp.PP, ms []Monitor, message string) bool {
 	ok := true
 	for _, m := range ms {
 		if !m.Failure(ctx, ppfmt, message) {
@@ -47,7 +48,7 @@ func FailureAll(ctx context.Context, ppfmt pp.PP, message string, ms []Monitor)
 }
 
 // LogAll calls [Monitor.Log] for each monitor in ms.
-func LogAll(ctx context.Context, ppfmt pp.PP, message string, ms []Monitor) bool {
+func LogAll(ctx context.Context, ppfmt pp.PP, ms []Monitor, message string) bool {
 	ok := true
 	for _, m := range ms {
 		if !m.Log(ctx, ppfmt, message) {
@@ -58,7 +59,7 @@ func LogAll(ctx context.Context, ppfmt pp.PP, message string, ms []Monitor) bool
 }
 
 // ExitStatusAll calls [Monitor.ExitStatus] for each monitor in ms.
-func ExitStatusAll(ctx context.Context, ppfmt pp.PP, code int, message string, ms []Monitor) bool {
+func ExitStatusAll(ctx context.Context, ppfmt pp.PP, ms []Monitor, code int, message string) bool {
 	ok := true
 	for _, m := range ms {
 		if !m.ExitStatus(ctx, ppfmt, code, message) {
@@ -67,3 +68,14 @@ func ExitStatusAll(ctx context.Context, ppfmt pp.PP, code int, message string, m
 	}
 	return ok
 }
+
+// SendAll calls [Send] for each monitor in ms.
+func SendAll(ctx context.Context, ppfmt pp.PP, ms []Monitor, resp response.Response) bool {
+	ok := true
+	for _, m := range ms {
+		if !Send(ctx, ppfmt, m, resp) {
+			ok = false
+		}
+	}
+	return ok
+}

internal/monitor/composite_test.go

@@ -2,12 +2,14 @@ package monitor_test
 
 import (
 	"context"
+	"strings"
 	"testing"
 
 	"go.uber.org/mock/gomock"
 
 	"github.com/favonia/cloudflare-ddns/internal/mocks"
 	"github.com/favonia/cloudflare-ddns/internal/monitor"
+	"github.com/favonia/cloudflare-ddns/internal/response"
 )
 
 func TestDescribeAll(t *testing.T) {
@@ -43,7 +45,7 @@ func TestSuccessAll(t *testing.T) {
 		ms = append(ms, m)
 	}
 
-	monitor.SuccessAll(context.Background(), mockPP, message, ms)
+	monitor.SuccessAll(context.Background(), mockPP, ms, message)
 }
 
 func TestStartAll(t *testing.T) {
@@ -62,7 +64,7 @@ func TestStartAll(t *testing.T) {
 		ms = append(ms, m)
 	}
 
-	monitor.StartAll(context.Background(), mockPP, message, ms)
+	monitor.StartAll(context.Background(), mockPP, ms, message)
 }
 
 func TestFailureAll(t *testing.T) {
@@ -81,7 +83,7 @@ func TestFailureAll(t *testing.T) {
 		ms = append(ms, m)
 	}
 
-	monitor.FailureAll(context.Background(), mockPP, message, ms)
+	monitor.FailureAll(context.Background(), mockPP, ms, message)
 }
 
 func TestLogAll(t *testing.T) {
@@ -100,10 +102,10 @@ func TestLogAll(t *testing.T) {
 		ms = append(ms, m)
 	}
 
-	monitor.LogAll(context.Background(), mockPP, message, ms)
+	monitor.LogAll(context.Background(), mockPP, ms, message)
 }
 
-func TestMonitorsExitStatus(t *testing.T) {
+func TestExitStatusAll(t *testing.T) {
 	t.Parallel()
 
 	ms := make([]monitor.Monitor, 0, 5)
@@ -119,5 +121,45 @@ func TestMonitorsExitStatus(t *testing.T) {
 		ms = append(ms, m)
 	}
 
-	monitor.ExitStatusAll(context.Background(), mockPP, 42, message, ms)
+	monitor.ExitStatusAll(context.Background(), mockPP, ms, 42, message)
+}
+
+func TestSendAll(t *testing.T) {
+	t.Parallel()
+
+	monitorMessages := []string{"forest", "grass"}
+	monitorMessage := strings.Join(monitorMessages, "\n")
+	notifierMessages := []string{"ocean"}
+
+	for name, tc := range map[string]struct {
+		ok bool
+	}{
+		"ok":    {true},
+		"notok": {false},
+	} {
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			ms := make([]monitor.Monitor, 0, 5)
+			mockCtrl := gomock.NewController(t)
+			mockPP := mocks.NewMockPP(mockCtrl)
+
+			for range 5 {
+				m := mocks.NewMockMonitor(mockCtrl)
+				if tc.ok {
+					m.EXPECT().Log(context.Background(), mockPP, monitorMessage)
+				} else {
+					m.EXPECT().Failure(context.Background(), mockPP, monitorMessage)
+				}
+				ms = append(ms, m)
+			}
+
+			resp := response.Response{
+				Ok:               tc.ok,
+				MonitorMessages:  monitorMessages,
+				NotifierMessages: notifierMessages,
+			}
+			monitor.SendAll(context.Background(), mockPP, ms, resp)
+		})
+	}
 }

internal/response/response.go

@@ -0,0 +1,35 @@
+package response
+
+type Response struct {
+	Ok               bool
+	MonitorMessages  []string
+	NotifierMessages []string
+}
+
+func NewEmpty() Response {
+	return Response{
+		Ok:               true,
+		MonitorMessages:  nil,
+		NotifierMessages: nil,
+	}
+}
+
+func Merge(rs ...Response) Response {
+	var (
+		allOk               = true
+		allMonitorMessages  = map[bool][]string{true: {}, false: {}}
+		allNotifierMessages = []string{}
+	)
+
+	for _, r := range rs {
+		allOk = allOk && r.Ok
+		allMonitorMessages[r.Ok] = append(allMonitorMessages[r.Ok], r.MonitorMessages...)
+		allNotifierMessages = append(allNotifierMessages, r.NotifierMessages...)
+	}
+
+	return Response{
+		Ok:               allOk,
+		MonitorMessages:  allMonitorMessages[allOk],
+		NotifierMessages: allNotifierMessages,
+	}
+}

internal/setter/base.go

@@ -17,18 +17,6 @@ import (
 
 //go:generate mockgen -typed -destination=../mocks/mock_setter.go -package=mocks . Setter
 
-// ResponseCode encodes the minimum information to generate messages for monitors and notifiers.
-type ResponseCode int
-
-const (
-	// No updates were needed. The records were already okay.
-	ResponseNoUpdatesNeeded = iota
-	// Updates were needed and they are done.
-	ResponseUpdatesApplied
-	// Updates were needed and they did not fully complete. The records may be inconsistent.
-	ResponseUpdatesFailed
-)
-
 // Setter uses [api.Handle] to update DNS records.
 type Setter interface {
 	// Set sets a particular domain to the given IP address.

internal/setter/code.go

@@ -0,0 +1,20 @@
+package setter
+
+// ResponseCode encodes the minimum information to generate messages for monitors and notifiers.
+type ResponseCode int
+
+const (
+	// ResponseNoop means no changes were needed.
+	// The records were already updated or already deleted.
+	ResponseNoop ResponseCode = iota
+
+	// ResponseUpdated means records should be updated
+	// and we updated them, or that they should be deleted
+	// and we deleted them.
+	ResponseUpdated
+
+	// ResponseFailed means records should be updated
+	// but we failed to finish the updating, or that they
+	// should be deleted and we failed to finish the deletion.
+	ResponseFailed
+)

internal/setter/setter.go

@@ -55,7 +55,7 @@ func (s *setter) Set(ctx context.Context, ppfmt pp.PP,
 	rs, ok := s.Handle.ListRecords(ctx, ppfmt, domain, ipnet)
 	if !ok {
 		ppfmt.Errorf(pp.EmojiError, "Failed to retrieve the current %s records of %q", recordType, domainDescription)
-		return ResponseUpdatesFailed
+		return ResponseFailed
 	}
 
 	// The intention of these two lists is to find or create a good record and then delete everything else.
@@ -77,7 +77,7 @@ func (s *setter) Set(ctx context.Context, ppfmt pp.PP,
 	// If it's up to date and there are no other records, we are done!
 	if foundMatched && len(unprocessedMatched) == 0 && len(unprocessedUnmatched) == 0 {
 		ppfmt.Infof(pp.EmojiAlreadyDone, "The %s records of %q are already up to date", recordType, domainDescription)
-		return ResponseNoUpdatesNeeded
+		return ResponseNoop
 	}
 
 	// This counts the stale records that have not being deleted yet.
@@ -164,12 +164,12 @@ func (s *setter) Set(ctx context.Context, ppfmt pp.PP,
 	// Check whether we are done. It is okay to have duplicates, but it is not okay to have remaining stale records.
 	if !foundMatched || numUndeletedUnmatched > 0 {
 		ppfmt.Errorf(pp.EmojiError,
-			"Failed to complete updating of %s records of %q; records might be inconsistent",
+			"Failed to finish updating %s records of %q; records might be inconsistent",
 			recordType, domainDescription)
-		return ResponseUpdatesFailed
+		return ResponseFailed
 	}
 
-	return ResponseUpdatesApplied
+	return ResponseUpdated
 }
 
 // Delete deletes all managed DNS records.
@@ -180,7 +180,7 @@ func (s *setter) Delete(ctx context.Context, ppfmt pp.PP, domain domain.Domain,
 	rmap, ok := s.Handle.ListRecords(ctx, ppfmt, domain, ipnet)
 	if !ok {
 		ppfmt.Errorf(pp.EmojiError, "Failed to retrieve the current %s records of %q", recordType, domainDescription)
-		return ResponseUpdatesFailed
+		return ResponseFailed
 	}
 
 	// Sorting is not needed for correctness, but it will make the function deterministic.
@@ -192,7 +192,7 @@ func (s *setter) Delete(ctx context.Context, ppfmt pp.PP, domain domain.Domain,
 
 	if len(unmatchedIDs) == 0 {
 		ppfmt.Infof(pp.EmojiAlreadyDone, "The %s records of %q were already deleted", recordType, domainDescription)
-		return ResponseNoUpdatesNeeded
+		return ResponseNoop
 	}
 
 	allOk := true
@@ -206,10 +206,10 @@ func (s *setter) Delete(ctx context.Context, ppfmt pp.PP, domain domain.Domain,
 	}
 	if !allOk {
 		ppfmt.Errorf(pp.EmojiError,
-			"Failed to complete deleting of %s records of %q; records might be inconsistent",
+			"Failed to finish deleting %s records of %q; records might be inconsistent",
 			recordType, domainDescription)
-		return ResponseUpdatesFailed
+		return ResponseFailed
 	}
 
-	return ResponseUpdatesApplied
+	return ResponseUpdated
 }