Support for primary and fallback download client

frontend/src/Settings/DownloadClients/DownloadClients/DownloadClient.js

@@ -54,7 +54,8 @@ class DownloadClient extends Component {
     const {
       id,
       name,
-      enable
+      enable,
+      priority
     } = this.props;
 
     return (
@@ -80,6 +81,16 @@ class DownloadClient extends Component {
                 Disabled
               </Label>
           }
+
+          {
+            priority > 1 &&
+              <Label
+                kind={kinds.DISABLED}
+                outline={true}
+              >
+                Priority: {priority}
+              </Label>
+          }
         </div>
 
         <EditDownloadClientModalConnector
@@ -107,6 +118,7 @@ DownloadClient.propTypes = {
   id: PropTypes.number.isRequired,
   name: PropTypes.string.isRequired,
   enable: PropTypes.bool.isRequired,
+  priority: PropTypes.number.isRequired,
   onConfirmDeleteDownloadClient: PropTypes.func.isRequired
 };
 

frontend/src/Settings/DownloadClients/DownloadClients/EditDownloadClientModalContent.js

@@ -44,6 +44,7 @@ class EditDownloadClientModalContent extends Component {
       implementationName,
       name,
       enable,
+      priority,
       fields,
       message
     } = item;
@@ -115,6 +116,23 @@ class EditDownloadClientModalContent extends Component {
                   })
                 }
 
+                <FormGroup
+                  advancedSettings={advancedSettings}
+                  isAdvanced={true}
+                >
+                  <FormLabel>Client Priority</FormLabel>
+
+                  <FormInputGroup
+                    type={inputTypes.NUMBER}
+                    name="priority"
+                    helpText="Prioritize multiple Download Clients. Round-Robin is used for clients with the same priority."
+                    min={1}
+                    max={50}
+                    {...priority}
+                    onChange={onInputChange}
+                  />
+                </FormGroup>
+
               </Form>
           }
         </ModalBody>

src/Lidarr.Api.V1/DownloadClient/DownloadClientResource.cs

@@ -7,6 +7,7 @@ namespace Lidarr.Api.V1.DownloadClient
     {
         public bool Enable { get; set; }
         public DownloadProtocol Protocol { get; set; }
+        public int Priority { get; set; }
     }
 
     public class DownloadClientResourceMapper : ProviderResourceMapper<DownloadClientResource, DownloadClientDefinition>
@@ -19,6 +20,7 @@ namespace Lidarr.Api.V1.DownloadClient
 
             resource.Enable = definition.Enable;
             resource.Protocol = definition.Protocol;
+            resource.Priority = definition.Priority;
 
             return resource;
         }
@@ -31,6 +33,7 @@ namespace Lidarr.Api.V1.DownloadClient
 
             definition.Enable = resource.Enable;
             definition.Protocol = resource.Protocol;
+            definition.Priority = resource.Priority;
 
             return definition;
         }

src/NzbDrone.Core.Test/Datastore/Migration/036_add_download_client_priorityFixture.cs

@@ -0,0 +1,178 @@
+using System.Linq;
+using FluentAssertions;
+using Newtonsoft.Json.Linq;
+using NUnit.Framework;
+using NzbDrone.Common.Serializer;
+using NzbDrone.Core.Datastore.Migration;
+using NzbDrone.Core.Test.Framework;
+
+namespace NzbDrone.Core.Test.Datastore.Migration
+{
+    [TestFixture]
+    public class add_download_client_priorityFixture : MigrationTest<add_download_client_priority>
+    {
+        [Test]
+        public void should_set_prio_to_one()
+        {
+            var db = WithMigrationTestDb(c =>
+            {
+                c.Insert.IntoTable("DownloadClients").Row(new
+                {
+                    Enable = 1,
+                    Name = "Deluge",
+                    Implementation = "Deluge",
+                    Settings = new DelugeSettings36
+                    {
+                        Host = "127.0.0.1",
+                        MusicCategory = "abc",
+                        UrlBase = "/my/"
+                    }.ToJson(),
+                    ConfigContract = "DelugeSettings"
+                });
+            });
+
+            var items = db.Query<DownloadClientDefinition036>("SELECT * FROM DownloadClients");
+
+            items.Should().HaveCount(1);
+            items.First().Priority.Should().Be(1);
+        }
+
+        [Test]
+        public void should_renumber_prio_for_enabled_clients()
+        {
+            var db = WithMigrationTestDb(c =>
+            {
+                c.Insert.IntoTable("DownloadClients").Row(new
+                {
+                    Enable = 1,
+                    Name = "Deluge",
+                    Implementation = "Deluge",
+                    Settings = new DelugeSettings36
+                    {
+                        Host = "127.0.0.1",
+                        MusicCategory = "abc",
+                        UrlBase = "/my/"
+                    }.ToJson(),
+                    ConfigContract = "DelugeSettings"
+                }).Row(new
+                {
+                    Enable = 1,
+                    Name = "Deluge2",
+                    Implementation = "Deluge",
+                    Settings = new DelugeSettings36
+                    {
+                        Host = "127.0.0.1",
+                        MusicCategory = "abc",
+                        UrlBase = "/my/"
+                    }.ToJson(),
+                    ConfigContract = "DelugeSettings"
+                }).Row(new
+                {
+                    Enable = 1,
+                    Name = "sab",
+                    Implementation = "Sabnzbd",
+                    Settings = new SabnzbdSettings36
+                    {
+                        Host = "127.0.0.1",
+                        MusicCategory = "abc"
+                    }.ToJson(),
+                    ConfigContract = "SabnzbdSettings"
+                });
+            });
+
+            var items = db.Query<DownloadClientDefinition036>("SELECT * FROM DownloadClients");
+
+            items.Should().HaveCount(3);
+            items[0].Priority.Should().Be(1);
+            items[1].Priority.Should().Be(2);
+            items[2].Priority.Should().Be(1);
+        }
+
+        [Test]
+        public void should_not_renumber_prio_for_disabled_clients()
+        {
+            var db = WithMigrationTestDb(c =>
+            {
+                c.Insert.IntoTable("DownloadClients").Row(new
+                {
+                    Enable = 0,
+                    Name = "Deluge",
+                    Implementation = "Deluge",
+                    Settings = new DelugeSettings36
+                    {
+                        Host = "127.0.0.1",
+                        MusicCategory = "abc",
+                        UrlBase = "/my/"
+                    }.ToJson(),
+                    ConfigContract = "DelugeSettings"
+                }).Row(new
+                {
+                    Enable = 0,
+                    Name = "Deluge2",
+                    Implementation = "Deluge",
+                    Settings = new DelugeSettings36
+                    {
+                        Host = "127.0.0.1",
+                        MusicCategory = "abc",
+                        UrlBase = "/my/"
+                    }.ToJson(),
+                    ConfigContract = "DelugeSettings"
+                }).Row(new
+                {
+                    Enable = 0,
+                    Name = "sab",
+                    Implementation = "Sabnzbd",
+                    Settings = new SabnzbdSettings36
+                    {
+                        Host = "127.0.0.1",
+                        MusicCategory = "abc"
+                    }.ToJson(),
+                    ConfigContract = "SabnzbdSettings"
+                });
+            });
+
+            var items = db.Query<DownloadClientDefinition036>("SELECT * FROM DownloadClients");
+
+            items.Should().HaveCount(3);
+            items[0].Priority.Should().Be(1);
+            items[1].Priority.Should().Be(1);
+            items[1].Priority.Should().Be(1);
+        }
+    }
+
+    public class DownloadClientDefinition036
+    {
+        public int Id { get; set; }
+        public bool Enable { get; set; }
+        public int Priority { get; set; }
+        public string Name { get; set; }
+        public string Implementation { get; set; }
+        public JObject Settings { get; set; }
+        public string ConfigContract { get; set; }
+    }
+
+    public class DelugeSettings36
+    {
+        public string Host { get; set; }
+        public int Port { get; set; }
+        public string UrlBase { get; set; }
+        public string Password { get; set; }
+        public string MusicCategory { get; set; }
+        public int RecentTvPriority { get; set; }
+        public int OlderTvPriority { get; set; }
+        public bool UseSsl { get; set; }
+    }
+
+    public class SabnzbdSettings36
+    {
+        public string Host { get; set; }
+        public int Port { get; set; }
+        public string ApiKey { get; set; }
+        public string Username { get; set; }
+        public string Password { get; set; }
+        public string MusicCategory { get; set; }
+        public int RecentTvPriority { get; set; }
+        public int OlderTvPriority { get; set; }
+        public bool UseSsl { get; set; }
+    }
+}

src/NzbDrone.Core.Test/Download/DownloadClientProviderFixture.cs

@@ -35,13 +35,14 @@ namespace NzbDrone.Core.Test.Download
                   .Returns(_blockedProviders);
         }
 
-        private Mock<IDownloadClient> WithUsenetClient()
+        private Mock<IDownloadClient> WithUsenetClient(int priority = 0)
         {
             var mock = new Mock<IDownloadClient>(MockBehavior.Default);
             mock.SetupGet(s => s.Definition)
                 .Returns(Builder<DownloadClientDefinition>
                     .CreateNew()
                     .With(v => v.Id = _nextId++)
+                    .With(v => v.Priority = priority)
                     .Build());
 
             _downloadClients.Add(mock.Object);
@@ -51,13 +52,14 @@ namespace NzbDrone.Core.Test.Download
             return mock;
         }
 
-        private Mock<IDownloadClient> WithTorrentClient()
+        private Mock<IDownloadClient> WithTorrentClient(int priority = 0)
         {
             var mock = new Mock<IDownloadClient>(MockBehavior.Default);
             mock.SetupGet(s => s.Definition)
                 .Returns(Builder<DownloadClientDefinition>
                     .CreateNew()
                     .With(v => v.Id = _nextId++)
+                    .With(v => v.Priority = priority)
                     .Build());
 
             _downloadClients.Add(mock.Object);
@@ -181,5 +183,47 @@ namespace NzbDrone.Core.Test.Download
             client3.Definition.Id.Should().Be(4);
             client4.Definition.Id.Should().Be(2);
         }
+
+        [Test]
+        public void should_skip_secondary_prio_torrent_client()
+        {
+            WithUsenetClient();
+            WithTorrentClient(2);
+            WithTorrentClient();
+            WithTorrentClient();
+
+            var client1 = Subject.GetDownloadClient(DownloadProtocol.Torrent);
+            var client2 = Subject.GetDownloadClient(DownloadProtocol.Torrent);
+            var client3 = Subject.GetDownloadClient(DownloadProtocol.Torrent);
+            var client4 = Subject.GetDownloadClient(DownloadProtocol.Torrent);
+            var client5 = Subject.GetDownloadClient(DownloadProtocol.Torrent);
+
+            client1.Definition.Id.Should().Be(3);
+            client2.Definition.Id.Should().Be(4);
+            client3.Definition.Id.Should().Be(3);
+            client4.Definition.Id.Should().Be(4);
+        }
+
+        [Test]
+        public void should_not_skip_secondary_prio_torrent_client_if_primary_blocked()
+        {
+            WithUsenetClient();
+            WithTorrentClient(2);
+            WithTorrentClient(2);
+            WithTorrentClient();
+
+            GivenBlockedClient(4);
+
+            var client1 = Subject.GetDownloadClient(DownloadProtocol.Torrent);
+            var client2 = Subject.GetDownloadClient(DownloadProtocol.Torrent);
+            var client3 = Subject.GetDownloadClient(DownloadProtocol.Torrent);
+            var client4 = Subject.GetDownloadClient(DownloadProtocol.Torrent);
+            var client5 = Subject.GetDownloadClient(DownloadProtocol.Torrent);
+
+            client1.Definition.Id.Should().Be(2);
+            client2.Definition.Id.Should().Be(3);
+            client3.Definition.Id.Should().Be(2);
+            client4.Definition.Id.Should().Be(3);
+        }
     }
 }

src/NzbDrone.Core/Datastore/Migration/036_add_download_client_priority.cs

@@ -0,0 +1,56 @@
+using System.Collections.Generic;
+using System.Data;
+using FluentMigrator;
+using NzbDrone.Core.Datastore.Migration.Framework;
+
+namespace NzbDrone.Core.Datastore.Migration
+{
+    [Migration(036)]
+    public class add_download_client_priority : NzbDroneMigrationBase
+    {
+        // Need snapshot in time without having to instantiate.
+        private static HashSet<string> _usenetImplementations = new HashSet<string>
+        {
+            "Sabnzbd", "NzbGet", "NzbVortex", "UsenetBlackhole", "UsenetDownloadStation"
+        };
+
+        protected override void MainDbUpgrade()
+        {
+            Alter.Table("DownloadClients").AddColumn("Priority").AsInt32().WithDefaultValue(1);
+            Execute.WithConnection(InitPriorityForBackwardCompatibility);
+
+        }
+
+        private void InitPriorityForBackwardCompatibility(IDbConnection conn, IDbTransaction tran)
+        {
+            using (var cmd = conn.CreateCommand())
+            {
+                cmd.Transaction = tran;
+                cmd.CommandText = "SELECT Id, Implementation FROM DownloadClients WHERE Enable = 1";
+
+                using (var reader = cmd.ExecuteReader())
+                {
+                    int nextUsenet = 1;
+                    int nextTorrent = 1;
+                    while (reader.Read())
+                    {
+                        var id = reader.GetInt32(0);
+                        var implName = reader.GetString(1);
+
+                        var isUsenet = _usenetImplementations.Contains(implName);
+
+                        using (var updateCmd = conn.CreateCommand())
+                        {
+                            updateCmd.Transaction = tran;
+                            updateCmd.CommandText = "UPDATE DownloadClients SET Priority = ? WHERE Id = ?";
+                            updateCmd.AddParameter(isUsenet ? nextUsenet++ : nextTorrent++);
+                            updateCmd.AddParameter(id);
+
+                            updateCmd.ExecuteNonQuery();
+                        }
+                    }
+                }
+            }
+        }
+    }
+}

src/NzbDrone.Core/Download/DownloadClientDefinition.cs

@@ -6,5 +6,6 @@ namespace NzbDrone.Core.Download
     public class DownloadClientDefinition : ProviderDefinition
     {
         public DownloadProtocol Protocol { get; set; }
+        public int Priority { get; set; } = 1;
     }
 }

src/NzbDrone.Core/Download/DownloadClientProvider.cs

@@ -50,6 +50,11 @@ namespace NzbDrone.Core.Download
                 }
             }
 
+            // Use the first priority clients first
+            availableProviders = availableProviders.GroupBy(v => (v.Definition as DownloadClientDefinition).Priority)
+                                                   .OrderBy(v => v.Key)
+                                                   .First().OrderBy(v => v.Definition.Id).ToList();
+
             var lastId = _lastUsedDownloadClient.Find(downloadProtocol.ToString());
 
             var provider = availableProviders.FirstOrDefault(v => v.Definition.Id > lastId) ?? availableProviders.First();