Commit `7b880ea410`

7b880ea410f37a7df22594ed9b268448621db4d8

parent: 8b661d9f36

Unsigned

cmc <hello@cleberg.net> · 2026-07-20 20:33 UTC

fix: report unreachable domains instead of 'No meaningful changes'

Closes #10.

resolvedSnapshotAfterFallback replaces a failed lookup's snapshot with
the previous one, so alertDescriptor compared the old snapshot against
itself, found matching hashes, and the run reported 'No meaningful
changes' for a domain that was never actually reached. Nothing in the
UI or the monitoring log distinguished that from a genuine no-change.

MonitoringDomainResult now carries unreachableReason, set when the
fallback fires. It is Optional so already-persisted monitoring logs
still decode. The run summary reads 'Could not check — kept the previous
result' with the underlying error, and monitoringEvents emits a warning-
severity monitoringFailure so configured integrations hear about it
rather than seeing silence.

Layout: unified · split

DomainDig/DomainMonitoringService.swift +41 −2

		@@ -291,6 +291,12 @@ final class DomainMonitoringService {
291	291	previousSnapshot: previousSnapshot
292	292	)
293	293	let snapshot = Self.resolvedSnapshotAfterFallback(inspectedSnapshot, previousSnapshot: previousSnapshot)
	294	// When the fallback fires, `snapshot` is `previousSnapshot`, so
	295	// every comparison below is old-against-old and would otherwise
	296	// report "No meaningful changes" for a domain we never reached.
	297	let unreachableReason = (previousSnapshot != nil && Self.shouldFallbackToSnapshot(inspectedSnapshot))
	298	? Self.firstErrorMessage(in: inspectedSnapshot)
	299	: nil
294	300	let savedEntry: HistoryEntry?
295	301	if snapshot.statusMessage == nil {
296	302	savedEntry = persistSnapshot(
		@@ -330,14 +336,16 @@ final class DomainMonitoringService {
330	336	historyEntryID: savedEntry?.id ?? snapshot.historyEntryID,
331	337	checkedAt: now,
332	338	didChange: alertDescriptor != nil,
333		summaryMessage: snapshot.statusMessage
	339	summaryMessage: unreachableReason.map { "Could not check — kept the previous result. \($0)" }
	340	?? snapshot.statusMessage
334	341	?? alertDescriptor?.message
335	342	?? savedEntry?.changeSummary?.message
336	343	?? "No meaningful changes",
337	344	alertSeverity: alertDescriptor?.severity,
338	345	certificateWarningLevel: DomainDiffService.certificateWarningLevel(for: snapshot),
339	346	resultSource: snapshot.resultSource,
340		errorMessage: snapshot.statusMessage
	347	errorMessage: snapshot.statusMessage,
	348	unreachableReason: unreachableReason
341	349	)
342	350	results.append(result)
343	351
		@@ -397,6 +405,21 @@ final class DomainMonitoringService {
397	405	)
398	406	}
399	407
	408	if let unreachableReason = result.unreachableReason {
	409	return MonitoringEvent(
	410	type: .monitoringFailure,
	411	severity: .warning,
	412	domain: result.domain,
	413	timestamp: result.checkedAt,
	414	summary: result.summaryMessage,
	415	details: [
	416	"reason": unreachableReason,
	417	"trigger": log.trigger.rawValue,
	418	"resultSource": result.resultSource.rawValue
	419	]
	420	)
	421	}
	422
400	423	if result.certificateWarningLevel == .critical {
401	424	return MonitoringEvent(
402	425	type: .certificateExpiring,
		@@ -943,6 +966,22 @@ final class DomainMonitoringService {
943	966	)
944	967	}
945	968
	969	/// First reported error on a snapshot, used to explain a fallback. Mirrors
	970	/// the ordering `shouldFallbackToSnapshot` inspects.
	971	private static func firstErrorMessage(in snapshot: LookupSnapshot) -> String {
	972	[
	973	snapshot.dnsError,
	974	snapshot.httpHeadersError,
	975	snapshot.sslError,
	976	snapshot.ownershipError,
	977	snapshot.subdomainsError,
	978	snapshot.redirectChainError,
	979	snapshot.ipGeolocationError
	980	]
	981	.compactMap { $0 }
	982	.first ?? "The lookup could not reach the domain."
	983	}
	984
946	985	private static func shouldFallbackToSnapshot(_ snapshot: LookupSnapshot) -> Bool {
947	986	let candidateMessages = [
948	987	snapshot.dnsError,

DomainDig/Models.swift +7 −1

		@@ -1544,6 +1544,10 @@ struct MonitoringDomainResult: Codable, Identifiable, Equatable {
1544	1544	let certificateWarningLevel: CertificateWarningLevel
1545	1545	let resultSource: LookupResultSource
1546	1546	let errorMessage: String?
	1547	/// Non-nil when the lookup failed and the previous snapshot was reused, so
	1548	/// this run compared the old data against itself and cannot claim the
	1549	/// domain is unchanged. Optional so already-persisted logs still decode.
	1550	let unreachableReason: String?
1547	1551
1548	1552	init(
1549	1553	id: UUID = UUID(),
		@@ -1555,7 +1559,8 @@ struct MonitoringDomainResult: Codable, Identifiable, Equatable {
1555	1559	alertSeverity: MonitoringAlertSeverity?,
1556	1560	certificateWarningLevel: CertificateWarningLevel,
1557	1561	resultSource: LookupResultSource,
1558		errorMessage: String? = nil
	1562	errorMessage: String? = nil,
	1563	unreachableReason: String? = nil
1559	1564	) {
1560	1565	self.id = id
1561	1566	self.domain = domain
		@@ -1567,6 +1572,7 @@ struct MonitoringDomainResult: Codable, Identifiable, Equatable {
1567	1572	self.certificateWarningLevel = certificateWarningLevel
1568	1573	self.resultSource = resultSource
1569	1574	self.errorMessage = errorMessage
	1575	self.unreachableReason = unreachableReason
1570	1576	}
1571	1577	}
1572	1578

Commit 7b880ea410

Commit `7b880ea410`