Merge branch 'add-chained-error-pr'

3 files changed, 82 insertions, 1 deletions

diff --git a/ios/MullvadVPN.xcodeproj/project.pbxproj b/ios/MullvadVPN.xcodeproj/project.pbxproj
index 3797d9e87d..fed0afca2b 100644
--- a/ios/MullvadVPN.xcodeproj/project.pbxproj
+++ b/ios/MullvadVPN.xcodeproj/project.pbxproj
@@ -3,7 +3,7 @@
 	archiveVersion = 1;
 	classes = {
 	};
-	objectVersion = 50;
+	objectVersion = 52;
 	objects = {
 
 /* Begin PBXBuildFile section */
@@ -99,6 +99,7 @@
 		58B0A2AD238EE6EC00BC001D /* MullvadEndpoint.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5840250322B11AB700E4CFEC /* MullvadEndpoint.swift */; };
 		58B8743222B25A7600015324 /* WireguardAssociatedAddresses.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58B8743122B25A7600015324 /* WireguardAssociatedAddresses.swift */; };
 		58B8743B22B788D200015324 /* PacketTunnelSettingsGenerator.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58B8743722B25EAB00015324 /* PacketTunnelSettingsGenerator.swift */; };
+		58B9EB152489139B00095626 /* DisplayChainedError.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58B9EB142489139B00095626 /* DisplayChainedError.swift */; };
 		58BA692E23E99EFF009DC256 /* Locking.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58BA692D23E99EFF009DC256 /* Locking.swift */; };
 		58BA692F23E99F5B009DC256 /* Locking.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58BA692D23E99EFF009DC256 /* Locking.swift */; };
 		58BA693123EADA6A009DC256 /* SimulatorTunnelProvider.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58BA693023EADA6A009DC256 /* SimulatorTunnelProvider.swift */; };
@@ -139,6 +140,8 @@
 		58F19E35228C15BA00C7710B /* SpinnerActivityIndicatorView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58F19E34228C15BA00C7710B /* SpinnerActivityIndicatorView.swift */; };
 		58F840AF2464382C0044E708 /* KeychainItemRevision.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58F840AE2464382C0044E708 /* KeychainItemRevision.swift */; };
 		58F840B02464382C0044E708 /* KeychainItemRevision.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58F840AE2464382C0044E708 /* KeychainItemRevision.swift */; };
+		58F840B22464491D0044E708 /* ChainedError.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58F840B12464491D0044E708 /* ChainedError.swift */; };
+		58F840B32464491D0044E708 /* ChainedError.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58F840B12464491D0044E708 /* ChainedError.swift */; };
 		58FAEDEF245069C700CB0F5B /* KeychainAttributes.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58FAEDEB245059F000CB0F5B /* KeychainAttributes.swift */; };
 		58FAEDF1245069CA00CB0F5B /* KeychainAttributes.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58FAEDEB245059F000CB0F5B /* KeychainAttributes.swift */; };
 		58FAEDF4245088B300CB0F5B /* KeychainError.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58AEEF642344A36000C9BBD5 /* KeychainError.swift */; };
@@ -264,6 +267,7 @@
 		58B0A2A4238EE67E00BC001D /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
 		58B8743122B25A7600015324 /* WireguardAssociatedAddresses.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = WireguardAssociatedAddresses.swift; sourceTree = "<group>"; };
 		58B8743722B25EAB00015324 /* PacketTunnelSettingsGenerator.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PacketTunnelSettingsGenerator.swift; sourceTree = "<group>"; };
+		58B9EB142489139B00095626 /* DisplayChainedError.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = DisplayChainedError.swift; sourceTree = "<group>"; };
 		58BA692D23E99EFF009DC256 /* Locking.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Locking.swift; sourceTree = "<group>"; };
 		58BA693023EADA6A009DC256 /* SimulatorTunnelProvider.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SimulatorTunnelProvider.swift; sourceTree = "<group>"; };
 		58BFA5C522A7C97F00A6173D /* RelayCache.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = RelayCache.swift; sourceTree = "<group>"; };
@@ -300,6 +304,7 @@
 		58ECD29123F178FD004298B6 /* Screenshots.xcconfig */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.xcconfig; path = Screenshots.xcconfig; sourceTree = "<group>"; };
 		58F19E34228C15BA00C7710B /* SpinnerActivityIndicatorView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SpinnerActivityIndicatorView.swift; sourceTree = "<group>"; };
 		58F840AE2464382C0044E708 /* KeychainItemRevision.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = KeychainItemRevision.swift; sourceTree = "<group>"; };
+		58F840B12464491D0044E708 /* ChainedError.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ChainedError.swift; sourceTree = "<group>"; };
 		58FAEDEB245059F000CB0F5B /* KeychainAttributes.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = KeychainAttributes.swift; sourceTree = "<group>"; };
 		58FAEDF6245088E100CB0F5B /* Keychain.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Keychain.swift; sourceTree = "<group>"; };
 		58FAEDFC24533A5500CB0F5B /* KeychainMatchLimit.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = KeychainMatchLimit.swift; sourceTree = "<group>"; };
@@ -418,11 +423,13 @@
 				589AB4F6227B64450039131E /* BasicTableViewCell.swift */,
 				58EC4E6B23915325003F5C5B /* Bundle+MullvadVersion.swift */,
 				584E96B9240D791E00D3334F /* CancellableDelayPublisher.swift */,
+				58F840B12464491D0044E708 /* ChainedError.swift */,
 				58A1AA8B23F5584B009F7EA6 /* ConnectionPanelView.swift */,
 				58CCA00F224249A1004F3011 /* ConnectViewController.swift */,
 				58A99ED2240014A0006599E9 /* ConsentViewController.swift */,
 				582BB1B0229569620055B6EF /* CustomNavigationBar.swift */,
 				58C6B35D22BBBFE3003C19AD /* Data+HexCoding.swift */,
+				58B9EB142489139B00095626 /* DisplayChainedError.swift */,
 				5873884C239E6D7E00E96C4E /* EmbeddedViewContainerView.swift */,
 				58FD5BF32428C67600112C88 /* InAppPurchaseButton.swift */,
 				58CE5E6F224146210008646E /* Info.plist */,
@@ -855,6 +862,7 @@
 				58CCA01222424D11004F3011 /* SettingsViewController.swift in Sources */,
 				58FD5BF42428C67600112C88 /* InAppPurchaseButton.swift in Sources */,
 				589AB4F7227B64450039131E /* BasicTableViewCell.swift in Sources */,
+				58B9EB152489139B00095626 /* DisplayChainedError.swift in Sources */,
 				5888AD7F2279B6BF0051EB06 /* RelayStatusIndicatorView.swift in Sources */,
 				5867A51C2248F26A005513C0 /* SegueIdentifier.swift in Sources */,
 				58CCA01E2242787B004F3011 /* AccountTextField.swift in Sources */,
@@ -872,6 +880,7 @@
 				58FD5BF22424F7D700112C88 /* UserInterfaceInteractionRestriction.swift in Sources */,
 				5811DE50239014550011EB53 /* NEVPNStatus+Debug.swift in Sources */,
 				58C3A4B222456F1B00340BDB /* AccountInputGroupView.swift in Sources */,
+				58F840B22464491D0044E708 /* ChainedError.swift in Sources */,
 				58FAEDFF24533A7000CB0F5B /* KeychainReturn.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
@@ -915,6 +924,7 @@
 				584E96BD240FD4DA00D3334F /* Location.swift in Sources */,
 				58FAEDF8245088E100CB0F5B /* Keychain.swift in Sources */,
 				58C6B36122C0EC82003C19AD /* AnyIPEndpoint+DNS64.swift in Sources */,
+				58F840B32464491D0044E708 /* ChainedError.swift in Sources */,
 				58C6B36722C106FC003C19AD /* WireguardCommand.swift in Sources */,
 				58561C9A239A5D1500BD6B5E /* IPEndpoint.swift in Sources */,
 				588534BF246193D90018B744 /* AutomaticKeyRotationManager.swift in Sources */,
diff --git a/ios/MullvadVPN/ChainedError.swift b/ios/MullvadVPN/ChainedError.swift
new file mode 100644
index 0000000000..71e0fff44d
--- /dev/null
+++ b/ios/MullvadVPN/ChainedError.swift
@@ -0,0 +1,58 @@
+//
+//  ErrorChain.swift
+//  MullvadVPN
+//
+//  Created by pronebird on 07/05/2020.
+//  Copyright © 2020 Mullvad VPN AB. All rights reserved.
+//
+
+import Foundation
+import os
+
+/// A protocol describing errors that can be chained together
+protocol ChainedError: LocalizedError {
+    /// A source error when available
+    var source: Error? { get }
+}
+
+extension ChainedError {
+
+    var source: Error? {
+        let reflection = Mirror(reflecting: self)
+
+        if case .enum = reflection.displayStyle {
+            for child in reflection.children {
+                if let associatedError = child.value as? Error {
+                    return associatedError
+                }
+            }
+        }
+
+        return nil
+    }
+
+    /// Creates a string representation of the entire error chain.
+    /// An extra `message` is added at the start of the chain when given
+    func displayChain(message: String? = nil) -> String {
+        var s = message.map { "Error: \($0)\nCaused by: \(self.localizedDescription)" }
+            ?? "Error: \(self.localizedDescription)"
+
+        for sourceError in makeChainIterator() {
+            s.append("\nCaused by: \(sourceError.localizedDescription)")
+        }
+
+        return s
+    }
+
+    func logChain(message: String? = nil, log: OSLog = .default) {
+        os_log(.error, log: log, "%{public}s", displayChain(message: message))
+    }
+
+    private func makeChainIterator() -> AnyIterator<Error> {
+        var current: Error? = self
+        return AnyIterator { () -> Error? in
+            current = (current as? ChainedError)?.source
+            return current
+        }
+    }
+}
diff --git a/ios/MullvadVPN/DisplayChainedError.swift b/ios/MullvadVPN/DisplayChainedError.swift
new file mode 100644
index 0000000000..7f67e8102f
--- /dev/null
+++ b/ios/MullvadVPN/DisplayChainedError.swift
@@ -0,0 +1,13 @@
+//
+//  DisplayChainedError.swift
+//  MullvadVPN
+//
+//  Created by pronebird on 04/06/2020.
+//  Copyright © 2020 Mullvad VPN AB. All rights reserved.
+//
+
+import Foundation
+
+protocol DisplayChainedError {
+    var errorChainDescription: String? { get }
+}