Updated the cachedEncodedPublicKey to be Atomic

Added the Atomic wrapper for thread safe variables

Session.xcodeproj/project.pbxproj

@@ -787,6 +787,7 @@
 		FD88BAD927A7439C00BBC442 /* MessageRequestsCell.swift in Sources */ = {isa = PBXBuildFile; fileRef = FD88BAD827A7439C00BBC442 /* MessageRequestsCell.swift */; };
 		FD88BADB27A750F200BBC442 /* MessageRequestsMigration.swift in Sources */ = {isa = PBXBuildFile; fileRef = FD88BADA27A750F200BBC442 /* MessageRequestsMigration.swift */; };
 		FDC4389E27BA2B8A00C60D73 /* SessionUtilitiesKit.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = C3C2A679255388CC00C340D1 /* SessionUtilitiesKit.framework */; };
+		FDFD645827EC1F4000808CA1 /* Atomic.swift in Sources */ = {isa = PBXBuildFile; fileRef = FDFD645727EC1F4000808CA1 /* Atomic.swift */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXContainerItemProxy section */
@@ -1829,6 +1830,7 @@
 		FD88BAD827A7439C00BBC442 /* MessageRequestsCell.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MessageRequestsCell.swift; sourceTree = "<group>"; };
 		FD88BADA27A750F200BBC442 /* MessageRequestsMigration.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MessageRequestsMigration.swift; sourceTree = "<group>"; };
 		FD9039443F7CB729CF71350E /* Pods-GlobalDependencies-FrameworkAndExtensionDependencies-SessionNotificationServiceExtension.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-GlobalDependencies-FrameworkAndExtensionDependencies-SessionNotificationServiceExtension.debug.xcconfig"; path = "Pods/Target Support Files/Pods-GlobalDependencies-FrameworkAndExtensionDependencies-SessionNotificationServiceExtension/Pods-GlobalDependencies-FrameworkAndExtensionDependencies-SessionNotificationServiceExtension.debug.xcconfig"; sourceTree = "<group>"; };
+		FDFD645727EC1F4000808CA1 /* Atomic.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Atomic.swift; sourceTree = "<group>"; };
 		FEDBAE1B98C49BBE8C87F575 /* Pods-GlobalDependencies-FrameworkAndExtensionDependencies-ExtendedDependencies-SessionUtilitiesKit.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-GlobalDependencies-FrameworkAndExtensionDependencies-ExtendedDependencies-SessionUtilitiesKit.debug.xcconfig"; path = "Pods/Target Support Files/Pods-GlobalDependencies-FrameworkAndExtensionDependencies-ExtendedDependencies-SessionUtilitiesKit/Pods-GlobalDependencies-FrameworkAndExtensionDependencies-ExtendedDependencies-SessionUtilitiesKit.debug.xcconfig"; sourceTree = "<group>"; };
 		FF9BA33D021B115B1F5B4E46 /* Pods-SessionMessagingKit.app store release.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-SessionMessagingKit.app store release.xcconfig"; path = "Pods/Target Support Files/Pods-SessionMessagingKit/Pods-SessionMessagingKit.app store release.xcconfig"; sourceTree = "<group>"; };
 /* End PBXFileReference section */
@@ -2339,6 +2341,7 @@
 				C33FDB8A255A581200E217F9 /* AppContext.h */,
 				C33FDB85255A581100E217F9 /* AppContext.m */,
 				C3C2A5D12553860800C340D1 /* Array+Utilities.swift */,
+				FDFD645727EC1F4000808CA1 /* Atomic.swift */,
 				C33FDAA8255A57FF00E217F9 /* BuildConfiguration.swift */,
 				B8F5F58225EC94A6003BF8D4 /* Collection+Subscripting.swift */,
 				B8AE75A325A6C6A6001A84D2 /* Data+Trimming.swift */,
@@ -4680,6 +4683,7 @@
 				C32C5DDB256DD9FF003C73A2 /* ContentProxy.swift in Sources */,
 				C3A71F892558BA9F0043A11F /* Mnemonic.swift in Sources */,
 				B8F5F58325EC94A6003BF8D4 /* Collection+Subscripting.swift in Sources */,
+				FDFD645827EC1F4000808CA1 /* Atomic.swift in Sources */,
 				C33FDEF8255A656D00E217F9 /* Promise+Delaying.swift in Sources */,
 				B8BC00C0257D90E30032E807 /* General.swift in Sources */,
 				C32C5A24256DB7DB003C73A2 /* SNUserDefaults.swift in Sources */,

Session/Settings/NukeDataModal.swift

@@ -128,7 +128,7 @@ final class NukeDataModal : Modal {
             appDelegate.forceSyncConfigurationNowIfNeeded().ensure(on: DispatchQueue.main) {
                 self?.dismiss(animated: true, completion: nil) // Dismiss the loader
                 UserDefaults.removeAll() // Not done in the nuke data implementation as unlinking requires this to happen later
-                General.Cache.cachedEncodedPublicKey = nil // Remove the cached key so it gets re-cached on next access
+                General.Cache.cachedEncodedPublicKey.mutate { $0 = nil } // Remove the cached key so it gets re-cached on next access
                 NotificationCenter.default.post(name: .dataNukeRequested, object: nil)
             }.retainUntilComplete()
         }
@@ -140,7 +140,7 @@ final class NukeDataModal : Modal {
                 self?.dismiss(animated: true, completion: nil) // Dismiss the loader
                 let potentiallyMaliciousSnodes = confirmations.compactMap { $0.value == false ? $0.key : nil }
                 if potentiallyMaliciousSnodes.isEmpty {
-                    General.Cache.cachedEncodedPublicKey = nil // Remove the cached key so it gets re-cached on next access
+                    General.Cache.cachedEncodedPublicKey.mutate { $0 = nil } // Remove the cached key so it gets re-cached on next access
                     UserDefaults.removeAll() // Not done in the nuke data implementation as unlinking requires this to happen later
                     NotificationCenter.default.post(name: .dataNukeRequested, object: nil)
                 } else {

SessionMessagingKit/Database/Storage+Shared.swift

@@ -40,7 +40,7 @@ extension Storage {
     }
     
     public func getUser(using transaction: YapDatabaseReadTransaction?) -> Contact? {
-        guard let userPublicKey = getUserPublicKey() else { return nil }
+        let userPublicKey = getUserHexEncodedPublicKey()
         var result: Contact?
         
         if let transaction = transaction {

SessionMessagingKit/Utilities/General.swift

@@ -2,7 +2,7 @@ import Foundation
 
 public enum General {
     public enum Cache {
-        public static var cachedEncodedPublicKey: String? = nil
+        public static var cachedEncodedPublicKey: Atomic<String?> = Atomic(nil)
     }
 }
 
@@ -14,10 +14,10 @@ public class GeneralUtilities: NSObject {
 }
 
 public func getUserHexEncodedPublicKey() -> String {
-    if let cachedKey: String = General.Cache.cachedEncodedPublicKey { return cachedKey }
+    if let cachedKey: String = General.Cache.cachedEncodedPublicKey.wrappedValue { return cachedKey }
     
     if let keyPair = OWSIdentityManager.shared().identityKeyPair() { // Can be nil under some circumstances
-        General.Cache.cachedEncodedPublicKey = keyPair.hexEncodedPublicKey
+        General.Cache.cachedEncodedPublicKey.mutate { $0 = keyPair.hexEncodedPublicKey }
         return keyPair.hexEncodedPublicKey
     }
     

SessionUtilitiesKit/General/Atomic.swift

@@ -0,0 +1,44 @@
+// Copyright © 2022 Rangeproof Pty Ltd. All rights reserved.
+import Foundation
+
+// MARK: - Atomic<Value>
+/// The `Atomic<Value>` wrapper is a generic wrapper providing a thread-safe way to get and set a value
+///
+/// A write-up on the need for this class and it's approach can be found here:
+/// https://www.vadimbulavin.com/swift-atomic-properties-with-property-wrappers/
+/// there is also another approach which can be taken but it requires separate types for collections and results in
+/// a somewhat inconsistent interface between different `Atomic` wrappers
+@propertyWrapper
+public class Atomic<Value> {
+    private let queue: DispatchQueue = DispatchQueue(label: "io.oxen.\(UUID().uuidString)")
+    private var value: Value
+
+    /// In order to change the value you **must** use the `mutate` function
+    public var wrappedValue: Value {
+        return queue.sync { return value }
+    }
+
+    /// For more information see https://github.com/apple/swift-evolution/blob/master/proposals/0258-property-wrappers.md#projections
+    public var projectedValue: Atomic<Value> {
+        return self
+    }
+
+    // MARK: - Initialization
+    public init(_ initialValue: Value) {
+        self.value = initialValue
+    }
+
+    // MARK: - Functions
+    
+    public func mutate(_ mutation: (inout Value) -> Void) {
+        return queue.sync {
+            mutation(&value)
+        }
+    }
+}
+
+extension Atomic where Value: CustomDebugStringConvertible {
+    var debugDescription: String {
+        return value.debugDescription
+    }
+}