Add support for updates from GitHub

Common.csproj

@@ -170,6 +170,7 @@
     <Compile Include="Trace\Tracer.cs" />
     <Compile Include="Settings\Extensions.cs" />
     <Compile Include="Settings\GenericSettingsProvider.cs" />
+    <Compile Include="Update\GitHubRelease.cs" />
     <Compile Include="Update\UpdateCheck.cs" />
     <Compile Include="Update\VersionInfo.cs" />
     <Compile Include="Xml\XmlExtensions.cs" />
@@ -219,6 +220,11 @@
     <None Include="LICENSE.md" />
     <None Include="README.md" />
   </ItemGroup>
+  <ItemGroup>
+    <PackageReference Include="Newtonsoft.Json">
+      <Version>11.0.2</Version>
+    </PackageReference>
+  </ItemGroup>
   <Import Project="$(MSBuildBinPath)\Microsoft.CSHARP.Targets" />
   <ProjectExtensions>
     <VisualStudio>

Update/GitHubRelease.cs

@@ -0,0 +1,177 @@
+using Newtonsoft.Json;
+using Newtonsoft.Json.Converters;
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+
+namespace Common.Update
+{
+    public partial class GitHubRelease
+    {
+        [JsonProperty("url")]
+        public string Url { get; set; }
+
+        [JsonProperty("assets_url")]
+        public string AssetsUrl { get; set; }
+
+        [JsonProperty("upload_url")]
+        public string UploadUrl { get; set; }
+
+        [JsonProperty("html_url")]
+        public string HtmlUrl { get; set; }
+
+        [JsonProperty("id")]
+        public long Id { get; set; }
+
+        [JsonProperty("tag_name")]
+        public string TagName { get; set; }
+
+        [JsonProperty("target_commitish")]
+        public string TargetCommitish { get; set; }
+
+        [JsonProperty("name")]
+        public string Name { get; set; }
+
+        [JsonProperty("draft")]
+        public bool Draft { get; set; }
+
+        [JsonProperty("author")]
+        public Uploader Author { get; set; }
+
+        [JsonProperty("prerelease")]
+        public bool Prerelease { get; set; }
+
+        [JsonProperty("created_at")]
+        public DateTimeOffset CreatedAt { get; set; }
+
+        [JsonProperty("published_at")]
+        public DateTimeOffset PublishedAt { get; set; }
+
+        [JsonProperty("assets")]
+        public List<Asset> Assets { get; set; }
+
+        [JsonProperty("tarball_url")]
+        public string TarballUrl { get; set; }
+
+        [JsonProperty("zipball_url")]
+        public string ZipballUrl { get; set; }
+
+        [JsonProperty("body")]
+        public string Body { get; set; }
+    }
+
+    public class Asset
+    {
+        [JsonProperty("url")]
+        public string Url { get; set; }
+
+        [JsonProperty("id")]
+        public long Id { get; set; }
+
+        [JsonProperty("name")]
+        public string Name { get; set; }
+
+        [JsonProperty("label")]
+        public string Label { get; set; }
+
+        [JsonProperty("uploader")]
+        public Uploader Uploader { get; set; }
+
+        [JsonProperty("content_type")]
+        public string ContentType { get; set; }
+
+        [JsonProperty("state")]
+        public string State { get; set; }
+
+        [JsonProperty("size")]
+        public long Size { get; set; }
+
+        [JsonProperty("download_count")]
+        public long DownloadCount { get; set; }
+
+        [JsonProperty("created_at")]
+        public DateTimeOffset CreatedAt { get; set; }
+
+        [JsonProperty("updated_at")]
+        public DateTimeOffset UpdatedAt { get; set; }
+
+        [JsonProperty("browser_download_url")]
+        public string BrowserDownloadUrl { get; set; }
+    }
+
+    public class Uploader
+    {
+        [JsonProperty("login")]
+        public string Login { get; set; }
+
+        [JsonProperty("id")]
+        public long Id { get; set; }
+
+        [JsonProperty("avatar_url")]
+        public string AvatarUrl { get; set; }
+
+        [JsonProperty("gravatar_id")]
+        public string GravatarId { get; set; }
+
+        [JsonProperty("url")]
+        public string Url { get; set; }
+
+        [JsonProperty("html_url")]
+        public string HtmlUrl { get; set; }
+
+        [JsonProperty("followers_url")]
+        public string FollowersUrl { get; set; }
+
+        [JsonProperty("following_url")]
+        public string FollowingUrl { get; set; }
+
+        [JsonProperty("gists_url")]
+        public string GistsUrl { get; set; }
+
+        [JsonProperty("starred_url")]
+        public string StarredUrl { get; set; }
+
+        [JsonProperty("subscriptions_url")]
+        public string SubscriptionsUrl { get; set; }
+
+        [JsonProperty("organizations_url")]
+        public string OrganizationsUrl { get; set; }
+
+        [JsonProperty("repos_url")]
+        public string ReposUrl { get; set; }
+
+        [JsonProperty("events_url")]
+        public string EventsUrl { get; set; }
+
+        [JsonProperty("received_events_url")]
+        public string ReceivedEventsUrl { get; set; }
+
+        [JsonProperty("type")]
+        public string Type { get; set; }
+
+        [JsonProperty("site_admin")]
+        public bool SiteAdmin { get; set; }
+    }
+
+    public partial class GitHubRelease
+    {
+        public static GitHubRelease FromJson(string json) => JsonConvert.DeserializeObject<GitHubRelease>(json, Converter.Settings);
+    }
+
+    public static class Serialize
+    {
+        public static string ToJson(this GitHubRelease self) => JsonConvert.SerializeObject(self, Converter.Settings);
+    }
+
+    internal class Converter
+    {
+        public static readonly JsonSerializerSettings Settings = new JsonSerializerSettings
+        {
+            MetadataPropertyHandling = MetadataPropertyHandling.Ignore,
+            DateParseHandling = DateParseHandling.None,
+            Converters = {
+                new IsoDateTimeConverter { DateTimeStyles = DateTimeStyles.AssumeUniversal }
+            },
+        };
+    }
+}

Update/UpdateCheck.cs

@@ -8,6 +8,12 @@ using System.Threading.Tasks;
 
 namespace Common.Update
 {
+    public enum ServerType
+    {
+        Generic,
+        GitHub
+    }
+
     public static class UpdateCheck
     {
         public delegate void ApplicationShutdownDelegate();
@@ -18,6 +24,7 @@ namespace Common.Update
         public static ApplicationCurrentMessageDelegate ApplicationCurrentMessage = null;
         public static ApplicationUpdateMessageDelegate ApplicationUpdateMessage = null;
 
+        public static ServerType UpdateServerType;
         public static string UpdateServer;
         public static string UpdateFile;
         public static string ApplicationName { get; set; }
@@ -26,14 +33,11 @@ namespace Common.Update
         public static string LocalInstallFile { get; private set; }
         public static bool UpdateAvailable { get; private set; }
 
-        public static Version LocalVersion
+        public static Version LocalVersion => Assembly.GetEntryAssembly().GetName().Version;
-        {
-            get { return Assembly.GetEntryAssembly().GetName().Version; }
-        }
 
         public static bool CheckForUpdate()
         {
-            RemoteVersion = VersionInfo.Load(UpdateServer, UpdateFile);
+            RemoteVersion = VersionInfo.Load(UpdateServerType, UpdateServer, UpdateFile);
 
             if (RemoteVersion == null)
                 return false;

Update/VersionInfo.cs

@@ -1,5 +1,6 @@
 using Common.Debug;
 using System;
+using System.Net;
 using System.Xml.Linq;
 
 namespace Common.Update
@@ -10,7 +11,20 @@ namespace Common.Update
         public string InstallFile { get; set; }
         public DateTime InstallCreated { get; set; }
 
-        public static VersionInfo Load(string server, string file)
+        public static VersionInfo Load(ServerType updateServerType, string server, string file)
+        {
+            switch (updateServerType)
+            {
+                case ServerType.Generic:
+                    return LoadFile(server, file);
+                case ServerType.GitHub:
+                    return LoadGitHub(server);
+            }
+
+            return null;
+        }
+
+        private static VersionInfo LoadFile(string server, string file)
         {
             try
             {
@@ -44,5 +58,38 @@ namespace Common.Update
                 return null;
             }
         }
+
+        private static VersionInfo LoadGitHub(string server)
+        {
+            try
+            {
+                ServicePointManager.Expect100Continue = true;
+                ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;
+
+                using (var webClient = new WebClient())
+                {
+                    webClient.Headers.Add("User-Agent", UpdateCheck.ApplicationName);
+
+                    var json = webClient.DownloadString(server);
+
+                    var release = GitHubRelease.FromJson(json);
+
+                    var versionInfo = new VersionInfo
+                    {
+                        Version = Version.Parse(release.TagName),
+                        InstallFile = release.Assets[0].BrowserDownloadUrl,
+                        InstallCreated = release.Assets[0].CreatedAt.LocalDateTime
+                    };
+
+                    return versionInfo;
+                }
+            }
+            catch (Exception exception)
+            {
+                Tracer.WriteException(exception);
+
+                return null;
+            }
+        }
     }
 }