Refreshes token for intellisense (#1476)

* check if token refresh needed

* add more checks

* simplify logic

* add summary and change to false

* wip

* wip

* add ExpiresOn field to check when token needs to be refreshed

* expired token check

* wip

* wip

* wip

* update expiresOn check

* wip

* wip

* working refresh token

* add closing tag

* fix summary

* pr comments

* add max tolerance

* refactoring

* refactoring and updating descriptions

* remove comment

* pr updates

* more pr comments

* pr comments

* wip

* pr comments - add state tracker

* update comment

* fix type

* pr comments

* fix race condition

* wip

* pr comments

* add comment

* pr comments

* nullable int

* pr comments

* remove uri from map upon disconnect

* pr comments

* remove uri from map upon editor close

* pr comments

src/Microsoft.SqlTools.ServiceLayer/Connection/ConnectionService.cs

@@ -33,6 +33,7 @@ namespace Microsoft.SqlTools.ServiceLayer.Connection
         public const string AdminConnectionPrefix = "ADMIN:";
         internal const string PasswordPlaceholder = "******";
         private const string SqlAzureEdition = "SQL Azure";
+        public const int MaxTolerance = 2 * 60; // two minutes - standard tolerance across ADS for AAD tokens
 
         /// <summary>
         /// Singleton service instance
@@ -59,6 +60,11 @@ namespace Microsoft.SqlTools.ServiceLayer.Connection
         private readonly ConcurrentDictionary<CancelTokenKey, CancellationTokenSource> cancelTupleToCancellationTokenSourceMap =
                     new ConcurrentDictionary<CancelTokenKey, CancellationTokenSource>();
 
+        /// <summary>
+        /// A map containing the uris of connections with expired tokens, these editors should have intellisense
+        /// disabled until the new refresh token is returned, upon which they will be removed from the map
+        /// </summary>
+        public readonly ConcurrentDictionary<string, Boolean> TokenUpdateUris = new ConcurrentDictionary<string, Boolean>();
         private readonly object cancellationTokenSourceLock = new object();
 
         private ConcurrentDictionary<string, IConnectedBindingQueue> connectedQueues = new ConcurrentDictionary<string, IConnectedBindingQueue>();
@@ -228,11 +234,84 @@ namespace Microsoft.SqlTools.ServiceLayer.Connection
         public virtual bool TryFindConnection(string ownerUri, out ConnectionInfo connectionInfo) => this.OwnerToConnectionMap.TryGetValue(ownerUri, out connectionInfo);
 
         /// <summary>
-        /// Validates the given ConnectParams object. 
+        /// Refreshes the auth token of a given connection, if needed
         /// </summary>
-        /// <param name="connectionParams">The params to validate</param>
-        /// <returns>A ConnectionCompleteParams object upon validation error, 
-        /// null upon validation success</returns>
+        /// <param name="ownerUri">The URI of the connection</param>
+        /// <returns> True if a refreshed was needed and requested, false otherwise </returns>
+
+        internal async Task<bool> TryRequestRefreshAuthToken(string ownerUri)
+        {
+            ConnectionInfo connInfo;
+            if (this.TryFindConnection(ownerUri, out connInfo))
+            {
+                // If not an azure connection, no need to refresh token
+                if (connInfo.ConnectionDetails.AuthenticationType != "AzureMFA")
+                {
+                    return false;
+                }
+                else
+                {
+                    // Check if token is expired or about to expire
+                    if (connInfo.ConnectionDetails.ExpiresOn - DateTimeOffset.Now.ToUnixTimeSeconds() < MaxTolerance)
+                    {
+
+                        var requestMessage = new RefreshTokenParams
+                        {
+                            AccountId = connInfo.ConnectionDetails.GetOptionValue("azureAccount", string.Empty),
+                            TenantId = connInfo.ConnectionDetails.GetOptionValue("azureTenantId", string.Empty),
+                            Provider = "Azure",
+                            Resource = "SQL",
+                            Uri = ownerUri
+                        };
+                        if (string.IsNullOrEmpty(requestMessage.TenantId))
+                        {
+                            Logger.Error("No tenant in connection details when refreshing token for connection {ownerUri}");
+                            return false;
+                        }
+                        if (string.IsNullOrEmpty(requestMessage.AccountId))
+                        {
+                            Logger.Error("No accountId in connection details when refreshing token for connection {ownerUri}");
+                            return false;
+                        }
+                        // Check if the token is updating already, in which case there is no need to request a new one, 
+                        // but still return true so that autocompletion is disabled until the token is refreshed
+                        if (!this.TokenUpdateUris.TryAdd(ownerUri, true))
+                        {
+                            return true;
+                        }
+                        await this.ServiceHost.SendEvent(RefreshTokenNotification.Type, requestMessage);
+                        return true;
+                    }
+                    else
+                    {
+                        return false;
+                    }
+                }
+            }
+            else
+            {
+                Logger.Error("Failed to find connection when refreshing token");
+                return false;
+            }
+        }
+
+        /// <summary>
+        /// Requests an update of the azure auth token
+        /// </summary>
+        /// <param name="refreshToken">The token to update</param>
+        /// <returns>true upon successful update, false if it failed to find 
+        /// the connection</returns>
+        internal void UpdateAuthToken(TokenRefreshedParams tokenRefreshedParams)
+        {
+            if (!this.TryFindConnection(tokenRefreshedParams.Uri, out ConnectionInfo connection))
+            {
+                Logger.Error($"Failed to find connection when updating refreshed token for URI {tokenRefreshedParams.Uri}");
+                return;
+            }
+            this.TokenUpdateUris.Remove(tokenRefreshedParams.Uri, out var result);
+            connection.UpdateAuthToken(tokenRefreshedParams.Token, tokenRefreshedParams.ExpiresOn);
+        }
+
         public ConnectionCompleteParams ValidateConnectParams(ConnectParams connectionParams)
         {
             string paramValidationErrorMessage;
@@ -807,6 +886,10 @@ namespace Microsoft.SqlTools.ServiceLayer.Connection
                 return false;
             }
 
+            // This clears the uri of the connection from the tokenUpdateUris map, which is used to track
+            // open editors that have requested a refreshed AAD token.
+            this.TokenUpdateUris.Remove(disconnectParams.OwnerUri, out bool result);
+
             // Call Close() on the connections we want to disconnect
             // If no connections were located, return false
             if (!CloseConnections(info, disconnectParams.Type))
@@ -1318,7 +1401,7 @@ namespace Microsoft.SqlTools.ServiceLayer.Connection
                 ConnectionInfo info;
                 SqlConnectionStringBuilder connStringBuilder;
                 try
-                {   
+                {
                     // set connection string using connection uri if connection details are undefined
                     if (connStringParams.ConnectionDetails == null)
                     {