Add self-update mechanism (fixes #3)

.gitignore

@@ -22,6 +22,7 @@
 .db
 Thumbs.db
 /.idea
+/.vscode
 /results.xml
 
 /Assets/UPackages.meta

Assets/Plugins/Editor/Uplift/Initialize.cs

@@ -26,11 +26,13 @@
 using UnityEngine;
 using Uplift.Common;
 using Uplift.Schemas;
+using Uplift.Updating;
 using System;
 
 namespace Uplift
 {
     [InitializeOnLoad]
+    [ExecuteInEditMode]
     public class Initialize : MonoBehaviour
     {
         private static readonly string env_variable = "UPLIFT_INSTALLATION_DONE";
@@ -48,6 +50,8 @@ static Initialize()
                 UpliftManager.Instance().InstallDependencies(strategy: UpliftManager.InstallStrategy.ONLY_LOCKFILE, refresh: true);
                 MarkAsInitialized();
             }
+
+            Updater.CheckForUpdate();
         }
 
         private static bool IsInitialized()

Assets/Plugins/Editor/Uplift/MenuItems.cs

@@ -29,6 +29,7 @@
 using Uplift.Schemas;
 using Uplift.Packages;
 using Uplift.Common;
+using Uplift.Updating;
 using System.Linq;
 
 using Uplift.Export;
@@ -179,5 +180,11 @@ private static void AboutUplift()
         {
             EditorWindow.GetWindow(typeof(AboutWindow));
         }
+
+        [MenuItem("Tools/Uplift/Try to update Uplift", false, 2001)]
+        private static void TryUpdateUplift()
+        {
+            Updater.CheckForUpdate(true);
+        }
     }
 }

Assets/Plugins/Editor/Uplift/UpdateTool/Updater.cs

@@ -0,0 +1,303 @@
+// --- BEGIN LICENSE BLOCK ---
+/*
+ * Copyright (c) 2017-present WeWantToKnow AS
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+// --- END LICENSE BLOCK ---
+
+using UnityEngine;
+using UnityEditor;
+using System.IO;
+using System.Collections;
+using System.Collections.Generic;
+using Uplift.Common;
+using Uplift.GitHubModule;
+using Uplift.Windows;
+using System.Net;
+using System.Linq;
+using System;
+using System.Globalization;
+using System.Net.Security;
+using System.Security.Cryptography.X509Certificates;
+using System.Text;
+
+namespace Uplift.Updating
+{
+    public class Updater : MonoBehaviour
+    {
+        private static readonly string dateFormat = @"MM\/dd\/yyyy HH:mm";
+        private static readonly CultureInfo provider = CultureInfo.InvariantCulture;
+        private static readonly string lastUpdateCheckKey = "UpliftLastUpdateCheck";
+        private static IEnumerator updateCoroutine;
+        private static readonly string[] githubCertificatesString = new string[]
+        {
+// github.com
+@"-----BEGIN CERTIFICATE-----
+MIIHeTCCBmGgAwIBAgIQC/20CQrXteZAwwsWyVKaJzANBgkqhkiG9w0BAQsFADB1
+MQswCQYDVQQGEwJVUzEVMBMGA1UEChMMRGlnaUNlcnQgSW5jMRkwFwYDVQQLExB3
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+-----END CERTIFICATE-----
+",
+// DigiCert High Assurance EV Root CA
+@"-----BEGIN CERTIFICATE-----
+MIIDxTCCAq2gAwIBAgIQAqxcJmoLQJuPC3nyrkYldzANBgkqhkiG9w0BAQUFADBs
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+-----END CERTIFICATE-----
+",
+// DigiCert SHA2 Extended Validation Server CA
+@"-----BEGIN CERTIFICATE-----
+MIIEtjCCA56gAwIBAgIQDHmpRLCMEZUgkmFf4msdgzANBgkqhkiG9w0BAQsFADBs
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+8TUoE6smftX3eg==
+-----END CERTIFICATE-----
+",
+// Amazon S3 (provider for the release download) *.s3.amazonaws.com
+@"-----BEGIN CERTIFICATE-----
+MIIFWjCCBEKgAwIBAgIQBVG1kvpTzyBSuLcPJ1zBWTANBgkqhkiG9w0BAQsFADBk
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+zSJW0aSi1DadkZsifpr65AwgSuN5uGEhQas0glsN
+-----END CERTIFICATE-----
+"
+        };
+        private static bool trustUnknown;
+
+        public static void UpdateUplift(string url)
+        {
+            trustUnknown = UpliftPreferences.TrustUnknownCertificates();
+            string unitypackageName = url.Split('/').Last();
+            DirectoryInfo assetsPath = new DirectoryInfo(Application.dataPath);
+            string destination = Path.Combine(assetsPath.Parent.FullName, unitypackageName);
+
+            ServicePointManager.ServerCertificateValidationCallback = CertificateValidationCallback;
+            using (var client = new WebClient())
+            {
+                client.DownloadFile(url, destination);
+            }
+
+            AssetDatabase.ImportPackage(destination, false);
+        }
+
+        public static void CheckForUpdate(bool forceCheck = false)
+        {
+            if(forceCheck || ShouldCheck())
+            {
+                EditorApplication.update += EditorUpdate;
+                updateCoroutine = CheckForUpdateRoutine();
+            }
+        }
+
+        private static void EditorUpdate()
+        {
+            updateCoroutine.MoveNext();
+        }
+
+        private static bool ShouldCheck()
+        {
+            string lastCheck = EditorPrefs.GetString(lastUpdateCheckKey);
+            if(string.IsNullOrEmpty(lastCheck)) return true;
+
+            try
+            {
+                TimeSpan timeFromLastCheck = DateTime.UtcNow - DateTime.ParseExact(lastCheck, dateFormat, provider);
+                return timeFromLastCheck > TimeSpan.FromDays(1);
+            }
+            catch(FormatException e)
+            {
+                Debug.LogErrorFormat("The date stored for the last check of Uplift ({0}) is not in the correct format:\n{1}", lastCheck, e);
+            }
+            return true;
+        }
+
+        private static IEnumerator CheckForUpdateRoutine() {
+            IEnumerator e = GitHub.LoadReleases("https://api.github.com/repos/DragonBox/uplift/releases");
+            while (e.MoveNext()) yield return e.Current;
+
+            GitHubRelease[] releases = (GitHubRelease[]) e.Current;
+
+            if (releases == null)
+            {
+                Debug.LogError ("Unable to check for Uplift updates");
+            }
+            else if(!releases.Any(release => VersionParser.GreaterThan(release.tag, About.Version)))
+            {
+                Debug.Log("No udpate for Uplift available");
+            }
+            else
+            {
+                UpdatePopup popup = EditorWindow.GetWindow(typeof(UpdatePopup), true) as UpdatePopup;
+                popup.SetReleases(releases.Where(release => VersionParser.GreaterThan(release.tag, About.Version)).ToArray());
+            }
+            EditorApplication.update -= EditorUpdate;
+            EditorPrefs.SetString(
+                lastUpdateCheckKey,
+                DateTime.UtcNow.ToString(dateFormat, provider)
+            );
+        }
+
+        private static bool CertificateValidationCallback(
+            System.Object sender,
+            X509Certificate certificate,
+            X509Chain chain,
+            SslPolicyErrors sslPolicyErrors
+        )
+        {
+            bool correct = true;
+            if(sslPolicyErrors == SslPolicyErrors.None) return true;
+
+            X509Certificate[] githubCertificates = new X509Certificate[githubCertificatesString.Length];
+            for(int i = 0; i < githubCertificatesString.Length; i++)
+            {
+                githubCertificates[i] = new X509Certificate();
+                githubCertificates[i].Import(Encoding.ASCII.GetBytes(githubCertificatesString[i]));
+            }            
+
+            if(!(githubCertificates.Any(cert => cert.GetCertHashString() == certificate.GetCertHashString()) || trustUnknown))
+            {
+                Debug.LogErrorFormat("The received certificate ({0}) is not known by Uplift. We cannot download the update package. You could update Uplift manually, or go to Preferences and set 'Trust unknown certificates' to true.", certificate.GetCertHashString());
+                Debug.Log("Known certificates are:");
+                foreach(X509Certificate cert in githubCertificates)
+                    Debug.Log(" -- " + cert.GetCertHashString());
+                return false;
+            }
+
+            for (int i=0; i < chain.ChainStatus.Length; i++) {
+                if (chain.ChainStatus[i].Status == X509ChainStatusFlags.RevocationStatusUnknown) {
+                    continue;
+                }
+                chain.ChainPolicy.RevocationFlag = X509RevocationFlag.EntireChain;
+                chain.ChainPolicy.RevocationMode = X509RevocationMode.Online;
+                chain.ChainPolicy.UrlRetrievalTimeout = new TimeSpan (0, 1, 0);
+                chain.ChainPolicy.VerificationFlags = X509VerificationFlags.AllFlags;
+                bool chainIsValid = chain.Build ((X509Certificate2)certificate);
+                if (!chainIsValid) {
+                    correct = false;
+                    break;
+                }
+            }
+
+            return correct;
+        }
+    }
+}