Add log viewer to watch app

openHAB.xcodeproj/project.pbxproj

@@ -79,6 +79,7 @@
 		DA0776F0234788010086C685 /* UserData.swift in Sources */ = {isa = PBXBuildFile; fileRef = DA0776EF234788010086C685 /* UserData.swift */; };
 		DA0F37D023D4ACC7007EAB48 /* SliderRow.swift in Sources */ = {isa = PBXBuildFile; fileRef = DA0F37CF23D4ACC7007EAB48 /* SliderRow.swift */; };
 		DA15BFBD23C6726400BD8ADA /* ObservableOpenHABDataObject.swift in Sources */ = {isa = PBXBuildFile; fileRef = DA15BFBC23C6726400BD8ADA /* ObservableOpenHABDataObject.swift */; };
+		DA162BEC2CD3B53E0040DAE5 /* LogsViewer.swift in Sources */ = {isa = PBXBuildFile; fileRef = DA162BEB2CD3B53E0040DAE5 /* LogsViewer.swift */; };
 		DA19E25B22FD801D002F8F2F /* OpenHABGeneralTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = DA19E25A22FD801D002F8F2F /* OpenHABGeneralTests.swift */; };
 		DA21EAE22339621C001AB415 /* Throttler.swift in Sources */ = {isa = PBXBuildFile; fileRef = DA21EAE12339621C001AB415 /* Throttler.swift */; };
 		DA242C622C83588600AFB10D /* SettingsView.swift in Sources */ = {isa = PBXBuildFile; fileRef = DA242C612C83588600AFB10D /* SettingsView.swift */; };
@@ -346,6 +347,7 @@
 		DA0776EF234788010086C685 /* UserData.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = UserData.swift; sourceTree = "<group>"; };
 		DA0F37CF23D4ACC7007EAB48 /* SliderRow.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = SliderRow.swift; sourceTree = "<group>"; };
 		DA15BFBC23C6726400BD8ADA /* ObservableOpenHABDataObject.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ObservableOpenHABDataObject.swift; sourceTree = "<group>"; };
+		DA162BEB2CD3B53E0040DAE5 /* LogsViewer.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LogsViewer.swift; sourceTree = "<group>"; };
 		DA19E25A22FD801D002F8F2F /* OpenHABGeneralTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = OpenHABGeneralTests.swift; sourceTree = "<group>"; };
 		DA1C2E4B230DC28F00FACFB0 /* Appfile */ = {isa = PBXFileReference; lastKnownFileType = text; path = Appfile; sourceTree = "<group>"; };
 		DA1C2E4C230DC28F00FACFB0 /* SnapshotHelper.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SnapshotHelper.swift; sourceTree = "<group>"; };
@@ -775,6 +777,7 @@
 			isa = PBXGroup;
 			children = (
 				DA0775262346705F0086C685 /* ContentView.swift */,
+				DA162BEB2CD3B53E0040DAE5 /* LogsViewer.swift */,
 				DAC6608C236F771600F4501E /* PreferencesSwiftUIView.swift */,
 				DAF457A323DB7A820018B495 /* Rows */,
 				DAF457A723DBA2C40018B495 /* Utils */,
@@ -1460,6 +1463,7 @@
 				DA32D1B42C8C98C40018D974 /* IconWithAction.swift in Sources */,
 				DA07764A234683BC0086C685 /* SwitchRow.swift in Sources */,
 				DA2E0AA423DC96E9009B0A99 /* ImageWithAction.swift in Sources */,
+				DA162BEC2CD3B53E0040DAE5 /* LogsViewer.swift in Sources */,
 				DAF4578723D798A50018B495 /* TextLabelView.swift in Sources */,
 				DA0749DE23E0B5950057FA83 /* ColorPickerRow.swift in Sources */,
 				DA7224D223828D3400712D20 /* PreviewConstants.swift in Sources */,

openHABWatch/OpenHABWatch.swift

@@ -32,6 +32,10 @@ struct OpenHABWatch: App {
                     .tabItem {
                         Label("Preferences", systemSymbol: .circleFill)
                     }
+                LogsViewer()
+                    .tabItem {
+                        Label("Debug", systemSymbol: .circleFill)
+                    }
             }
             .tabViewStyle(.page)
             .environmentObject(settings)

openHABWatch/Views/LogsViewer.swift

@@ -0,0 +1,111 @@
+//
+//  LogView.swift
+//  openHABWatch
+//
+//  Created by Tim Müller-Seydlitz on 31.10.24.
+//  Copyright © 2024 openHAB e.V. All rights reserved.
+//
+
+import Foundation
+import OSLog
+import SwiftUI
+
+// Thanks to https://useyourloaf.com/blog/fetching-oslog-messages-in-swift/
+
+extension OSLogEntryLog.Level {
+  fileprivate var description: String {
+    switch self {
+    case .undefined: "undefined"
+    case .debug: "debug"
+    case .info: "info"
+    case .notice: "notice"
+    case .error: "error"
+    case .fault: "fault"
+    @unknown default: "default"
+    }
+  }
+}
+
+extension Logger {
+  static public func fetch(since date: Date,
+    predicateFormat: String) async throws -> [String] {
+    let store = try OSLogStore(scope: .currentProcessIdentifier)
+    let position = store.position(date: date)
+    let predicate = NSPredicate(format: predicateFormat)
+    let entries = try store.getEntries(
+        at: position,
+        matching: predicate
+    )
+
+    let dateFormatter = DateFormatter()
+    dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss"
+
+    var logs: [String] = []
+    for entry in entries {
+      try Task.checkCancellation()
+      if let log = entry as? OSLogEntryLog {
+        var attributedMessage = AttributedString(dateFormatter.string(from: entry.date))
+        attributedMessage.font = .headline
+
+        logs.append("""
+          \(dateFormatter.string(from: entry.date)): \
+          \(log.category):\(log.level.description): \
+          \(entry.composedMessage)\n
+          """)
+      } else {
+        logs.append("\(entry.date): \(entry.composedMessage)\n")
+      }
+    }
+
+    if logs.isEmpty { logs = ["Nothing found"] }
+    return logs
+  }
+}
+
+struct LogsViewer: View {
+    @State private var text = "Loading..."
+
+    static private let template = NSPredicate(format:
+      "(subsystem BEGINSWITH $PREFIX)")
+
+    let myFont = Font
+            .system(size: 10)
+            .monospaced()
+
+    private func fetchLogs() async -> String {
+        let calendar = Calendar.current
+        guard let dayAgo = calendar.date(byAdding: .day,
+          value: -1, to: Date.now) else {
+          return "Invalid calendar"
+        }
+
+        do {
+            let predicate = Self.template.withSubstitutionVariables(
+            [
+                "PREFIX": "org.openhab"
+            ])
+
+          let logs = try await Logger.fetch(since: dayAgo,
+            predicateFormat: predicate.predicateFormat)
+          return logs.joined()
+        } catch {
+          return error.localizedDescription
+        }
+      }
+
+    var body: some View {
+
+        ScrollView {
+          Text(text)
+            .font(myFont)
+            .padding()
+        }
+        .task {
+          text = await fetchLogs()
+        }
+    }
+}
+
+#Preview {
+    LogsViewer()
+}