Fixed: Validate calibre connection before saving root folder

src/NzbDrone.Core/RootFolders/RootFolderService.cs

@@ -2,11 +2,15 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
+using System.Net;
 using System.Threading.Tasks;
 using NLog;
 using NzbDrone.Common;
 using NzbDrone.Common.Disk;
 using NzbDrone.Common.Extensions;
+using NzbDrone.Common.Http;
+using NzbDrone.Core.Books.Calibre;
+using NzbDrone.Core.Exceptions;
 using NzbDrone.Core.MediaFiles;
 using NzbDrone.Core.MediaFiles.Commands;
 using NzbDrone.Core.Messaging.Commands;
@@ -30,16 +34,19 @@ namespace NzbDrone.Core.RootFolders
     {
         private readonly IRootFolderRepository _rootFolderRepository;
         private readonly IDiskProvider _diskProvider;
+        private readonly ICalibreProxy _calibreProxy;
         private readonly IManageCommandQueue _commandQueueManager;
         private readonly Logger _logger;
 
         public RootFolderService(IRootFolderRepository rootFolderRepository,
+                                 ICalibreProxy calibreProxy,
                                  IDiskProvider diskProvider,
                                  IManageCommandQueue commandQueueManager,
                                  Logger logger)
         {
             _rootFolderRepository = rootFolderRepository;
             _diskProvider = diskProvider;
+            _calibreProxy = calibreProxy;
             _commandQueueManager = commandQueueManager;
             _logger = logger;
         }
@@ -91,6 +98,12 @@ namespace NzbDrone.Core.RootFolders
             {
                 throw new UnauthorizedAccessException(string.Format("Root folder path '{0}' is not writable by user '{1}'", rootFolder.Path, Environment.UserName));
             }
+
+            if (rootFolder.IsCalibreLibrary)
+            {
+                // This will throw on failure
+                _calibreProxy.GetLibraryInfo(rootFolder.CalibreSettings);
+            }
         }
 
         public RootFolder Add(RootFolder rootFolder)