Harmony.NET is an API that enables local-network websocket communication with Logitech Harmony Hubs. Harmony.NET makes it easy to start and stop activities, press remote buttons, and more in .NET. Built with .NET Standard 2.0, compatible with .NET Core.

To quickly get started, install the package and head down to the quickstart below.

The easiest way to install Harmony.NET is via NuGet:

Install-Package Harmony.NET

To build from source, clone the repository and build HarmonyHub.sln in Visual Studio. The output files will be located in \HarmonyHub\HarmonyHub\bin\(Debug/Release)\netstandard2.0\Harmony.dll

Start by importing the library at the top of your file:

using Harmony;

From there, the first step is to get a reference to a Hub. This can be done in three ways

1. Using a DiscoveryService

   This is the best method to use if you don't know the Hub's IP address beforehand. A DiscoveryService broadcasts a probe over UDP every 5 seconds by default to discover Hubs on the network.

   First, define a new instance of the DiscoveryService:

   DiscoveryService Service = new DiscoveryService();

   Then, subscribe to the event listener HubFound on the service, which is called every time a new Hub is found:

   Service.HubFound += Service_HubFound;

   Finally, start discovery:

   Service.StartDiscovery();

   The event listener will be passed HubFoundEventArgs, which contains a HubInfo property which can be used to create a Hub

   private static async void HubFound(object sender, HubFoundEventArgs e) {
   			Hub Hub = new Hub(e.HubInfo);
   			. . .
   }

2. Using the Hub's IP Address and ID

   Another way to create a Hub is by using its IP Address and Remote ID.

   These properties can be retrieved from an existing Hub via:

   string IP = Hub.Info.IP;
   string RemoteID = Hub.Info.RemoteId;

   Or HubInfo via:

   string IP = HubInfo.IP;
   string RemoteID = HubInfo.RemoteId;

   To create the Hub, use the constructor:

   Hub Hub = new Hub(IP, RemoteID);

3. Saving and restoring the Hub with JSON

   You can also save the Hub's state to JSON:

   string Json = Hub.ToJson();

   Then, restore the state using that JSON:

   Hub Hub = Hub.FromJson(Json);

Harmony requires that each client provide a unique ID to communicate with it. The easiest way to get one of these is like so:

DeviceID ClientID = DeviceID.GetDeviceDefault();

However, it is also possible to create a completely custom Device ID just by using its constructor:

DeviceID ClientID = new DeviceID(
	deviceUUID: Guid.NewGuid().ToString("N"),
	deviceProductName: "lg-joan",
	deviceModelName: "lge-h8930"
);

The first step after obtaining a Hub instance is to connect to it using the DeviceID from earlier:

await Hub.ConnectAsync(ClientID);

Note: ConnectAsync, like most methods in Harmony.NET, is asynchronous. This means you should probably await it in an async function for best performance.

Next, you'll want to retrieve the list of devices and activities on this hub, which can be done using SyncConfigurationAsync:

await Hub.SyncConfigurationAsync();

Note: SyncConfigurationAsync does not return anything, it only updates the Hub itself. To access the raw data, use the Hub.Sync property. It is also unnecessary to call this often. Once every app launch should do.

1. Getting a device

   There are a few ways to grab an individual Device.

   The first is to look up a device by its model:

   Device Xbox = Hub.GetDeviceByModel("Xbox One", "Microsoft");
   
   // including the manufacturer is not always necessary
   Device Xbox = Hub.GetDeviceByModel("Xbox One");

   The second is to use a known device id:

   // getting the id
   string ID = MyDevice.ID;
   . . .
   // using the id
   Device MyDevice = Hub.GetDeviceById(ID);

   Finally, you can also use the Devices array on a Hub and any LINQ expressions to find exactly what you are looking for.

   Device Newest = Hub.Devices.OrderByDescending(device => device.AddedDate).First();

2. Controlling a device

   Devices are controlled via functions, akin to buttons on remotes. These Functions can be passed into various methods in the Hub to execute them:

   Function MyFunction = . . .; // see below for details on getting functions
   await Hub.PressButtonAsync(MyFunction);
   
   // hold button for two seconds
   Hub.StartHolding(MyFunction);
   await Task.Delay(2000);
   Hub.StopHolding();

While all activities are in the Activities array on a Hub, the easiest way to get a reference to one is by using its label or id:

Activity WatchTV = Hub.GetActivityById("12345678");
Activity WatchTV = Hub.GetActivityByLabel("Watch TV");

From there, starting and stopping the activity is trivial:

await Hub.StartActivity(WatchTV);
. . .
await Hub.StopActivity(); // stops the currently running activity, throws if there isn't one

Optionally, if you want to track the progress of stopping or stopping an activity, subscribe to Hub.ActivityProgress:

Hub.ActivityProgress += (sender, e) => {
	// e.progress is a double between 0 and 1
	Console.WriteLine("Starting activity. {0}% done.", Math.Floor(e.Progress * 100));
};

To control an activity, see the section below on retrieving functions

The easiest way to get a function is by using a Device Wrapper. A device wrapper provides easy access to commonly used functions.

Note: Despite the name, device wrappers can be used with both activities and devices.

There are currently three wrappers:

• The simplest one, DeviceWrapper provides power on, off, and toggle power.

• NumericNavigationWrapper, which inherits from DeviceWrapper, provides the number pad and navigation functions like up, down, select, etc.

• PlaybackWrapper, which inherits from NumericNavigationWrapper, provides functions like play, skip, etc.

See the examples below for how to use a PlaybackWrapper:

using Harmony.DeviceWrappers;
. . .
PlaybackWrapper DVDWrapper = new PlaybackWrapper(DVDPlayerDevice);
await Hub.PressButtonAsync(DVDWrapper.Play);

PlaybackWrapper PlaybackControls = new PlaybackWrapper(WatchTVActivity); // you can also control activities with wrappers
await Harmony.PressButtonAsync(PlaybackControls.Left);

Alternatively, for functions not available on a wrapper, a function can be retrieved using the GetFunctionByName method on a Controllable object (Device or Activity):

await Hub.PressButtonAsync(DVDPlayerDevice.GetFunctionByName("TopMenu"));

await Hub.PressButtonAsync(WatchTVActivity.GetFunctionByName("Guide"));

Finally, all Functions are available on Controllables either as one array or sorted into ControlGroups

Function Play = Device.GetControlGroupByName("TransportBasic").GetFunctionByName("Play");

// not recommended as these can be unreliable
Function Play = Device.Functions[4]; 
Function Play = Device.ControlGroups[5].Functions[1];

Harmony supports getting information about the user's TV providers and their channels.

First, you'll need to download information about the user. This includes the user's location, and TV provider and favorite channels for particular devices.

User User = await Hub.GetUserInfo();

Next, get the TV providers for a specific device, say a DirecTV DVR, and download the main provider's channels

// Get channels on DVR TV provider
ProviderList DirecTVProviders = User.Preferences.GetProvidersForDevice(DirecTV);

// There's usually only one provider per device, so just get the default
ProviderInfo ProviderInfo =	await Hub.GetInfoForProvider(DirecTVProviders.DefaultProviderId);

Once you have the provider's channels, you can access data like channel numbers, names, and popularity. For example, here's how to tune to the most popular channel:

Channel MostPopular = ProviderInfo.PopularChannels.First();
await Hub.ChangeChannel(MostPopular);
Console.WriteLine("Tuned to channel {0}", MostPopular.Station.FullName);

Or to tune to ESPN:

Channel ESPN = ProviderInfo.GetChannelByStationShortName("ESPN");
await Hub.ChangeChannel(ESPN);

Or a favorite channel:

string FavoriteChannelId = DirecTVProviders.DefaultFavoriteChannels.StationIDs.First();
Channel Favorite = ProviderInfo.GetChannelByStationID(FavoriteChannelId);
await Hub.ChangeChannel(Favorite);

Note that if you know the channel number in advance, you don't have to go through all of the steps above to tune to it.

await Harmony.ChangeChannel("206");

Harmony has an issue (or perhaps a feature) that prevents sending commands at regular intervals. For example, the third command will not be executed in the code below:

// broken
await Hub.PressButtonAsync(Wrapper.Up);
await Task.Delay(400);
await Hub.PressButtonAsync(Wrapper.Right);
await Task.Delay(400);
await Hub.PressButtonAsync(Wrapper.Select);

To fix this issue, Hub has a method PressButtonsAsync (note the "s") which allows sending multiple commands at a semi-regular interval:

// takes either a params Function array
await Hub.PressButtonsAsync(400, Wrapper.Number0, Wrapper.Number1, Wrapper.Number2);

// or an IEnumerable<Function>
await Hub.PressButtonsAsync(400, WatchTV.Functions.Where(fn => fn.Name.StartsWith("Number")));

The example above is equivalent to the following code (400ms difference between each call):

// works!
await Hub.PressButtonAsync(Wrapper.Number0);
await Task.Delay(600);
await Hub.PressButtonAsync(Wrapper.Number1);
await Task.Delay(200);
await Hub.PressButtonAsync(Wrapper.Number2);

This +/- 200ms adjustment can be changed by setting Hub.RepeatedCommandAdjustment to any ms value. Setting it to 0 will disable this feature.

This quickstart demonstrates discovering a hub, starting an activity, and tuning to a channel

DiscoveryService Service = new DiscoveryService();
Service.HubFound += async (sender, e) => {
	// stop discovery once we've found one hub
	Service.StopDiscovery();

	Hub Harmony = new Hub(e.HubInfo);
	await Harmony.ConnectAsync(DeviceID.GetDeviceDefault());
	await Harmony.SyncConfigurationAsync();

	// start activity watch tv
	Activity WatchTV = Harmony.GetActivityByLabel("Watch TV");
	await Harmony.StartActivity(WatchTV);

	// tune to ESPN
	await Harmony.ChangeChannel("206");
	PlaybackWrapper PlaybackControls = new PlaybackWrapper(WatchTV);

	// wait for channel to switch, and pause
	await Task.Delay(1000);
	await Harmony.PressButtonAsync(PlaybackControls.Pause);
};
Service.StartDiscovery();

If you have any problems or features you'd like to see me add to Harmony.NET, I'd be happy to hear about them. Please make a new issue

This project is licensed under the MIT License. See more information in the LICENSE file.

Copyright 2018 (c) John Lynch