[PM-336] Nullable Platform & Unowned Services (#5646)

* Nullable Platform & Unowned Services

* Fix build errors

* Format

src/Core/Utilities/CoreHelpers.cs

@@ -1,4 +1,7 @@
-using System.Globalization;
+#nullable enable
+
+using System.Diagnostics.CodeAnalysis;
+using System.Globalization;
 using System.Reflection;
 using System.Security.Cryptography;
 using System.Security.Cryptography.X509Certificates;
@@ -116,11 +119,11 @@ public static class CoreHelpers
         return Regex.Replace(thumbprint, @"[^\da-fA-F]", string.Empty).ToUpper();
     }
 
-    public static X509Certificate2 GetCertificate(string thumbprint)
+    public static X509Certificate2? GetCertificate(string thumbprint)
     {
         thumbprint = CleanCertificateThumbprint(thumbprint);
 
-        X509Certificate2 cert = null;
+        X509Certificate2? cert = null;
         var certStore = new X509Store(StoreName.My, StoreLocation.CurrentUser);
         certStore.Open(OpenFlags.ReadOnly);
         var certCollection = certStore.Certificates.Find(X509FindType.FindByThumbprint, thumbprint, false);
@@ -141,7 +144,7 @@ public static class CoreHelpers
     public async static Task<X509Certificate2> GetEmbeddedCertificateAsync(string file, string password)
     {
         var assembly = typeof(CoreHelpers).GetTypeInfo().Assembly;
-        using (var s = assembly.GetManifestResourceStream($"Bit.Core.{file}"))
+        using (var s = assembly.GetManifestResourceStream($"Bit.Core.{file}")!)
         using (var ms = new MemoryStream())
         {
             await s.CopyToAsync(ms);
@@ -153,14 +156,14 @@ public static class CoreHelpers
     {
         var assembly = Assembly.GetCallingAssembly();
         var resourceName = assembly.GetManifestResourceNames().Single(n => n.EndsWith(file));
-        using (var stream = assembly.GetManifestResourceStream(resourceName))
+        using (var stream = assembly.GetManifestResourceStream(resourceName)!)
         using (var reader = new StreamReader(stream))
         {
             return reader.ReadToEnd();
         }
     }
 
-    public async static Task<X509Certificate2> GetBlobCertificateAsync(string connectionString, string container, string file, string password)
+    public async static Task<X509Certificate2?> GetBlobCertificateAsync(string connectionString, string container, string file, string password)
     {
         try
         {
@@ -233,7 +236,7 @@ public static class CoreHelpers
             throw new ArgumentOutOfRangeException(nameof(length), "length cannot be less than zero.");
         }
 
-        if ((characters?.Length ?? 0) == 0)
+        if (string.IsNullOrEmpty(characters))
         {
             throw new ArgumentOutOfRangeException(nameof(characters), "characters invalid.");
         }
@@ -346,10 +349,10 @@ public static class CoreHelpers
     /// </summary>
     public static T CloneObject<T>(T obj)
     {
-        return JsonSerializer.Deserialize<T>(JsonSerializer.Serialize(obj));
+        return JsonSerializer.Deserialize<T>(JsonSerializer.Serialize(obj))!;
     }
 
-    public static bool SettingHasValue(string setting)
+    public static bool SettingHasValue([NotNullWhen(true)] string? setting)
     {
         var normalizedSetting = setting?.ToLowerInvariant();
         return !string.IsNullOrWhiteSpace(normalizedSetting) && !normalizedSetting.Equals("secret") &&
@@ -448,7 +451,8 @@ public static class CoreHelpers
         return output;
     }
 
-    public static string PunyEncode(string text)
+    [return: NotNullIfNotNull(nameof(text))]
+    public static string? PunyEncode(string? text)
     {
         if (text == "")
         {
@@ -473,21 +477,21 @@ public static class CoreHelpers
         }
     }
 
-    public static string FormatLicenseSignatureValue(object val)
+    public static string? FormatLicenseSignatureValue(object val)
     {
         if (val == null)
         {
             return string.Empty;
         }
 
-        if (val.GetType() == typeof(DateTime))
+        if (val is DateTime dateTimeVal)
         {
-            return ToEpocSeconds((DateTime)val).ToString();
+            return ToEpocSeconds(dateTimeVal).ToString();
         }
 
-        if (val.GetType() == typeof(bool))
+        if (val is bool boolVal)
         {
-            return val.ToString().ToLowerInvariant();
+            return boolVal.ToString().ToLowerInvariant();
         }
 
         if (val is PlanType planType)
@@ -625,7 +629,7 @@ public static class CoreHelpers
         return subName;
     }
 
-    public static string GetIpAddress(this Microsoft.AspNetCore.Http.HttpContext httpContext,
+    public static string? GetIpAddress(this Microsoft.AspNetCore.Http.HttpContext httpContext,
         GlobalSettings globalSettings)
     {
         if (httpContext == null)
@@ -652,7 +656,7 @@ public static class CoreHelpers
             (!globalSettings.SelfHosted && origin == "https://bitwarden.com");
     }
 
-    public static X509Certificate2 GetIdentityServerCertificate(GlobalSettings globalSettings)
+    public static X509Certificate2? GetIdentityServerCertificate(GlobalSettings globalSettings)
     {
         if (globalSettings.SelfHosted &&
             SettingHasValue(globalSettings.IdentityServer.CertificatePassword)
@@ -804,14 +808,16 @@ public static class CoreHelpers
     /// <param name="jsonData">The JSON data</param>
     /// <typeparam name="T">The type to deserialize into</typeparam>
     /// <returns></returns>
-    public static T LoadClassFromJsonData<T>(string jsonData) where T : new()
+    public static T LoadClassFromJsonData<T>(string? jsonData) where T : new()
     {
         if (string.IsNullOrWhiteSpace(jsonData))
         {
             return new T();
         }
 
+#nullable disable // TODO: Remove this and fix any callee warnings.
         return System.Text.Json.JsonSerializer.Deserialize<T>(jsonData, _jsonSerializerOptions);
+#nullable enable
     }
 
     public static string ClassToJsonData<T>(T data)
@@ -829,7 +835,7 @@ public static class CoreHelpers
         return list;
     }
 
-    public static string DecodeMessageText(this QueueMessage message)
+    public static string? DecodeMessageText(this QueueMessage message)
     {
         var text = message?.MessageText;
         if (string.IsNullOrWhiteSpace(text))
@@ -852,7 +858,7 @@ public static class CoreHelpers
             Encoding.UTF8.GetBytes(input1), Encoding.UTF8.GetBytes(input2));
     }
 
-    public static string ObfuscateEmail(string email)
+    public static string? ObfuscateEmail(string email)
     {
         if (email == null)
         {
@@ -886,7 +892,7 @@ public static class CoreHelpers
 
     }
 
-    public static string GetEmailDomain(string email)
+    public static string? GetEmailDomain(string email)
     {
         if (!string.IsNullOrWhiteSpace(email))
         {
@@ -906,7 +912,7 @@ public static class CoreHelpers
         return _whiteSpaceRegex.Replace(input, newValue);
     }
 
-    public static string RedactEmailAddress(string email)
+    public static string? RedactEmailAddress(string email)
     {
         if (string.IsNullOrWhiteSpace(email))
         {