Implement public client application global cache

Author: cheenamalhotra

src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/ActiveDirectoryAuthenticationProvider.cs

@@ -3,6 +3,8 @@
 // See the LICENSE file in the project root for more information.
 
 using System;
+using System.Collections.Concurrent;
+using System.Collections.Generic;
 using System.Linq;
 using System.Security;
 using System.Threading;
@@ -15,6 +17,9 @@ namespace Microsoft.Data.SqlClient
     /// <include file='../../../../../../doc/snippets/Microsoft.Data.SqlClient/ActiveDirectoryAuthenticationProvider.xml' path='docs/members[@name="ActiveDirectoryAuthenticationProvider"]/ActiveDirectoryAuthenticationProvider/*'/>
     public sealed class ActiveDirectoryAuthenticationProvider : SqlAuthenticationProvider
     {
+        private static ConcurrentDictionary<PublicClientAppKey, IPublicClientApplication> s_pcaMap
+            = new ConcurrentDictionary<PublicClientAppKey, IPublicClientApplication>();
+        private static readonly string s_nativeClientRedirectUri = "https://login.microsoftonline.com/common/oauth2/nativeclient";
         private static readonly string s_defaultScopeSuffix = "/.default";
         private readonly string _type = typeof(ActiveDirectoryAuthenticationProvider).Name;
         private readonly SqlClientLogger _logger = new SqlClientLogger();
@@ -67,10 +72,10 @@ public override void BeforeUnload(SqlAuthenticationMethod authentication)
         }
 
 #if NETSTANDARD
-        private Func<object> parentActivityOrWindowFunc = null;
+        private Func<object> _parentActivityOrWindowFunc = null;
 
         /// <include file='../../../../../../doc/snippets/Microsoft.Data.SqlClient/ActiveDirectoryAuthenticationProvider.xml' path='docs/members[@name="ActiveDirectoryAuthenticationProvider"]/SetParentActivityOrWindowFunc/*'/>
-        public void SetParentActivityOrWindowFunc(Func<object> parentActivityOrWindowFunc) => this.parentActivityOrWindowFunc = parentActivityOrWindowFunc;
+        public void SetParentActivityOrWindowFunc(Func<object> parentActivityOrWindowFunc) => this._parentActivityOrWindowFunc = parentActivityOrWindowFunc;
 #endif
 
 #if NETFRAMEWORK
@@ -108,51 +113,24 @@ public override Task<SqlAuthenticationToken> AcquireTokenAsync(SqlAuthentication
              *
              * https://docs.microsoft.com/en-us/azure/active-directory/develop/scenario-desktop-app-registration#redirect-uris
              */
-            string redirectURI = "https://login.microsoftonline.com/common/oauth2/nativeclient";
+            string redirectUri = s_nativeClientRedirectUri;
 
 #if NETCOREAPP
             if (parameters.AuthenticationMethod != SqlAuthenticationMethod.ActiveDirectoryDeviceCodeFlow)
             {
-                redirectURI = "http://localhost";
-            }
-#endif
-            IPublicClientApplication app;
-
-#if NETSTANDARD
-            if (parentActivityOrWindowFunc != null)
-            {
-                app = PublicClientApplicationBuilder.Create(_applicationClientId)
-                .WithAuthority(parameters.Authority)
-                .WithClientName(Common.DbConnectionStringDefaults.ApplicationName)
-                .WithClientVersion(Common.ADP.GetAssemblyVersion().ToString())
-                .WithRedirectUri(redirectURI)
-                .WithParentActivityOrWindow(parentActivityOrWindowFunc)
-                .Build();
+                redirectUri = "http://localhost";
             }
 #endif
+            PublicClientAppKey pcaKey = new PublicClientAppKey(parameters.Authority, redirectUri, _applicationClientId
 #if NETFRAMEWORK
-            if (_iWin32WindowFunc != null)
-            {
-                app = PublicClientApplicationBuilder.Create(_applicationClientId)
-                .WithAuthority(parameters.Authority)
-                .WithClientName(Common.DbConnectionStringDefaults.ApplicationName)
-                .WithClientVersion(Common.ADP.GetAssemblyVersion().ToString())
-                .WithRedirectUri(redirectURI)
-                .WithParentActivityOrWindow(_iWin32WindowFunc)
-                .Build();
-            }
+            , _iWin32WindowFunc
 #endif
-#if !NETCOREAPP
-            else
+#if NETSTANDARD
+            , _parentActivityOrWindowFunc
 #endif
-            {
-                app = PublicClientApplicationBuilder.Create(_applicationClientId)
-                .WithAuthority(parameters.Authority)
-                .WithClientName(Common.DbConnectionStringDefaults.ApplicationName)
-                .WithClientVersion(Common.ADP.GetAssemblyVersion().ToString())
-                .WithRedirectUri(redirectURI)
-                .Build();
-            }
+                );
+
+            IPublicClientApplication app = GetPublicClientAppInstance(pcaKey);
 
             if (parameters.AuthenticationMethod == SqlAuthenticationMethod.ActiveDirectoryIntegrated)
             {
@@ -320,5 +298,168 @@ private class CustomWebUi : ICustomWebUi
             public Task<Uri> AcquireAuthorizationCodeAsync(Uri authorizationUri, Uri redirectUri, CancellationToken cancellationToken)
                 => _acquireAuthorizationCodeAsyncCallback.Invoke(authorizationUri, redirectUri, cancellationToken);
         }
+
+        private IPublicClientApplication GetPublicClientAppInstance(PublicClientAppKey publicClientAppKey)
+        {
+            IPublicClientApplication clientApplicationInstance;
+
+            if (s_pcaMap.ContainsKey(publicClientAppKey))
+            {
+                s_pcaMap.TryGetValue(publicClientAppKey, out clientApplicationInstance);
+            }
+            else
+            {
+                clientApplicationInstance = CreateClientAppInstance(publicClientAppKey);
+                s_pcaMap.TryAdd(publicClientAppKey, clientApplicationInstance);
+            }
+            return clientApplicationInstance;
+        }
+
+        private IPublicClientApplication CreateClientAppInstance(PublicClientAppKey publicClientAppKey)
+        {
+            IPublicClientApplication publicClientApplication;
+
+#if NETSTANDARD
+            if (_parentActivityOrWindowFunc != null)
+            {
+                publicClientApplication = PublicClientApplicationBuilder.Create(publicClientAppKey._applicationClientId)
+                .WithAuthority(publicClientAppKey._authority)
+                .WithClientName(Common.DbConnectionStringDefaults.ApplicationName)
+                .WithClientVersion(Common.ADP.GetAssemblyVersion().ToString())
+                .WithRedirectUri(publicClientAppKey._redirectUri)
+                .WithParentActivityOrWindow(_parentActivityOrWindowFunc)
+                .Build();
+            }
+#endif
+#if NETFRAMEWORK
+            if (_iWin32WindowFunc != null)
+            {
+                publicClientApplication = PublicClientApplicationBuilder.Create(publicClientAppKey._applicationClientId)
+                .WithAuthority(publicClientAppKey._authority)
+                .WithClientName(Common.DbConnectionStringDefaults.ApplicationName)
+                .WithClientVersion(Common.ADP.GetAssemblyVersion().ToString())
+                .WithRedirectUri(publicClientAppKey._redirectUri)
+                .WithParentActivityOrWindow(_iWin32WindowFunc)
+                .Build();
+            }
+#endif
+#if !NETCOREAPP
+            else
+#endif
+            {
+                publicClientApplication = PublicClientApplicationBuilder.Create(publicClientAppKey._applicationClientId)
+                .WithAuthority(publicClientAppKey._authority)
+                .WithClientName(Common.DbConnectionStringDefaults.ApplicationName)
+                .WithClientVersion(Common.ADP.GetAssemblyVersion().ToString())
+                .WithRedirectUri(publicClientAppKey._redirectUri)
+                .Build();
+            }
+
+            return publicClientApplication;
+        }
+
+        internal class PublicClientAppKey
+        {
+            public readonly string _authority;
+            public readonly string _redirectUri;
+            public readonly string _applicationClientId;
+#if NETFRAMEWORK
+            public readonly Func<System.Windows.Forms.IWin32Window> _iWin32WindowFunc;
+#endif
+#if NETSTANDARD
+            public readonly Func<object> _parentActivityOrWindowFunc;
+#endif
+            private int _hashValue;
+
+            public PublicClientAppKey(string authority, string redirectUri, string applicationClientId
+#if NETFRAMEWORK
+            , Func<System.Windows.Forms.IWin32Window> iWin32WindowFunc
+#endif
+#if NETSTANDARD
+            , Func<object> parentActivityOrWindowFunc
+#endif
+                )
+            {
+                _authority = authority;
+                _redirectUri = redirectUri;
+                _applicationClientId = applicationClientId;
+#if NETFRAMEWORK
+                _iWin32WindowFunc = iWin32WindowFunc;
+#endif
+#if NETSTANDARD
+                _parentActivityOrWindowFunc = parentActivityOrWindowFunc;
+#endif
+            }
+
+            public override bool Equals(object obj)
+            {
+                if (obj == null)
+                {
+                    return false;
+                }
+
+                PublicClientAppKey pcaKey = obj as PublicClientAppKey;
+                return (string.CompareOrdinal(_authority, pcaKey._authority) == 0
+                  && string.CompareOrdinal(_redirectUri, pcaKey._redirectUri) == 0
+                  && string.CompareOrdinal(_applicationClientId, pcaKey._applicationClientId) == 0
+#if NETFRAMEWORK
+                  && pcaKey._iWin32WindowFunc == _iWin32WindowFunc
+#endif
+#if NETSTANDARD
+                  && pcaKey._parentActivityOrWindowFunc == _parentActivityOrWindowFunc
+#endif
+                  );
+            }
+
+            public override int GetHashCode()
+            {
+                return _hashValue;
+            }
+
+            private void CalculateHashCode()
+            {
+                _hashValue = base.GetHashCode();
+
+                if (_authority != null)
+                {
+                    unchecked
+                    {
+                        _hashValue = _hashValue * 17 + _authority.GetHashCode();
+                    }
+                }
+                if (_redirectUri != null)
+                {
+                    unchecked
+                    {
+                        _hashValue = _hashValue * 17 + _redirectUri.GetHashCode();
+                    }
+                }
+                if (_applicationClientId != null)
+                {
+                    unchecked
+                    {
+                        _hashValue = _hashValue * 17 + _applicationClientId.GetHashCode();
+                    }
+                }
+#if NETFRAMEWORK
+                if (_iWin32WindowFunc != null)
+                {
+                    unchecked
+                    {
+                        _hashValue = _hashValue * 17 + _iWin32WindowFunc.GetHashCode();
+                    }
+                }
+#endif
+#if NETSTANDARD
+                if (_parentActivityOrWindowFunc != null)
+                {
+                    unchecked
+                    {
+                        _hashValue = _hashValue * 17 + _parentActivityOrWindowFunc.GetHashCode();
+                    }
+                }
+#endif
+            }
+        }
     }
 }