HassClient

A Home Assistant .NET client using Web Socket API.

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Sample Usage

HassWSApi provides access to Web Socket communication and a multitude of common operations:

Connection

To start using the Web Socket API client, it should be connected to a Home Assistant instance.

The method ConnectAsync with ConnectionParameters will be used:

• Using Instance base URL: Connects using the Home Assistant instance base address (e.g. "http://localhost:8123") and a valid token. You can obtain a token ("Long-Lived Access Token") by logging into the frontend using a web browser, and going to your profile http://IP_ADDRESS:8123/profile.

var hassWSApi = new HassWSApi();
var connectionParameters = ConnectionParameters.CreateFromInstanceBaseUrl("http://localhost:8123", "HASS_TOKEN");
await hassWSApi.ConnectAsync(connectionParameters);

• Within an Add-on: Connects to a Home Assistant instance using the add-ons internal proxy.

var hassWSApi = new HassWSApi();
var connectionParameters = ConnectionParameters.CreateForAddonConnection();
await hassWSApi.ConnectAsync(connectionParameters);

Services

The KnownDomains and KnownServices enums are available to reduce the use of strings.

// Fetch all available services in the Home Assistant instance.
IEnumerable<ServiceDomain> serviceDomains = await hassWSApi.Services.ListAsync();

// This will call a service from the Home Assistant instance.
await hassWSApi.Services.CallAsync("homeassistant", "check_config");

// Optional data can be passed to the call operation.
await hassWSApi.Services.CallAsync(KnownDomains.Light, KnownServices.TurnOn, data: new { entity_id = "light.my_light", brightness_pct = 20});

// When only entity_id is needed for the invocation this overload can be used.
await hassWSApi.Services.CallForEntitiesAsync(KnownDomains.Light, KnownServices.Toggle, "light.my_light1", "light.my_light2");

Fetching states

# Gets a collection with the state of every registered entity in the Home Assistant instance.
IEnumerable<StateModel> states = await hassWSApi.ListStatesAsync();

An event is produced by the Home Assistant instance every time a change_state occurs. To simplify the subscription to these events the StateChangedEventListener can be used:

public void Subscribe()
{
    // Subscribe to changes of a specific entity.
    hassWSApi.StateChangedEventListener.SubscribeEntityStatusChanged("light.my_light1", this.my_light1_StateChanged);
}

private void my_light1_StateChanged(object sender, StateChangedEvent stateChangedArgs)
{
    Debug.WriteLine($"my_light1_StateChanged {stateChangedArgs.EntityId} is now {stateChangedArgs.NewState.State}");
}

public void Subscribe()
{   
   // Subscribe to changes by domain.
   hassWSApi.StateChangedEventListener.SubscribeDomainStatusChanged("switch", this.Switch_StateChanged);
}

private void Switch_StateChanged(object sender, StateChangedEvent stateChangedArgs)
{
   Debug.WriteLine($"Switch_StateChanged {stateChangedArgs.EntityId} is now {stateChangedArgs.NewState.State}");
}

Fetching other data

// Fetch current Home Assistant instance configuration.
ConfigurationModel config = await hassWSApi.GetConfigurationAsync();

// Fetch current registered panels in Home Assistant instance.
IEnumerable<PanelInfo> panels = await hassWSApi.ListPanelsAsync();

Event subscription

The WS Client provides some methods to subscribe and unsubscribe to Home Assistant events.

Even any eventType can be specified as a string. The KnownEventTypes enum is available to reduce the use of strings.

public async Task MyMethod()
{
   // Subscribe to every event type
   await hassWSApi.AddEventHandlerSubscriptionAsync(this.WS_OnEvent);

   // Subscribe to specific event type
   await hassWSApi.AddEventHandlerSubscriptionAsync(this.WS_OnEvent, KnownEventTypes.PanelsUpdated);

   // Unsubscribe using the same event type from subscription
   await hassWSApi.RemoveEventHandlerSubscriptionAsync(this.WS_OnEvent, KnownEventTypes.PanelsUpdated);
}

private void WS_OnEvent(object sender, EventResultInfo eventResultInfo)
{
   Debug.WriteLine($"WS_OnEvent {eventResultInfo} => {eventResultInfo.Data}");
}

Render Template

Render a Home Assistant template. See template docs for more information.

string result = await hassWSApi.RenderTemplateAsync("Paulus is at {{ states('sun.sun') }} {{ states('binary_sensor.is_rainy') }}!");

RegistryEntry Collections

Home Assistant defines a Registry Collection as a registry of items identified by a unique id. Some common operations like list, create, update and delete are exposed through the Web Socket API and can be consumed using this client.

The following registry entries are supported:

• Area
• Category
• Device
• EntityRegistryEntry
• Floor
• Label
• User
• Zone

// List
IEnumerable<Area> areas = await hassWSApi.Areas.ListAsync();

// Create
var hallArea = new Area("Hall");
bool createResult = await hassWSApi.Areas.CreateAsync(hallArea);

// Update
hallArea.Name = "Hall_1";
hallArea.Labels.Add("ground_floor");
bool updateResult = await hassWSApi.Areas.UpdateAsync(hallArea);

// Pending changes
bool hasChanges = hallArea.HasPendingChanges;
hallArea.DiscardPendingChanges();

// Delete
bool deleteResult = await hassWSApi.Areas.DeleteAsync(hallArea);

Storage Collections

A Storage Collection contains a special registry entry type to store entities. The Web Socket API exposes four methods to list, create, update and delete these types of entries.

At the moment only InputBoolean, Person, and Zone entity models are defined.

// List
IEnumerable<InputBoolean> inputBooleans = await hassWSApi.StorageEntities.ListAsync<InputBoolean>();

// Create
var alarmInputBoolean = new InputBoolean("Alarm");
bool createResult = await hassWSApi.StorageEntities.CreateAsync(alarmInputBoolean);

// Update
alarmInputBoolean.Name = "Alarm_1";
alarmInputBoolean.Icon = "mdi:alarm";
bool updateResult = await hassWSApi.StorageEntities.UpdateAsync(alarmInputBoolean);

// Pending changes
bool hasChanges = alarmInputBoolean.HasPendingChanges;
alarmInputBoolean.DiscardPendingChanges();

// Delete
bool deleteResult = await hassWSApi.StorageEntities.DeleteAsync(alarmInputBoolean);

Key features of registry entries:

• Pending Changes: All registry entries track their modifications through the HasPendingChanges property
• Force Update: The update methods support a forceUpdate parameter to update all properties, not just the modified ones
• Discard Changes: You can revert pending changes using the DiscardPendingChanges() method
• Property Tracking: Properties like Name, Icon, Aliases, Labels, etc. are automatically tracked for changes

Search related

All data stored in Home Assistant is interconnected, making it a graph. The client allows searching related items for a given ItemTypes and itemId.

SearchRelatedResponse result = await hassWSApi.SearchRelatedAsync(ItemTypes.Entity, "weather.home");

Raw Commands

Even though many commands are implemented natively by this API client, some may not. For this purpose, a raw command API is available to send custom commands and receive raw results.

// Send raw command message with raw result
RawCommandResult rawResult = await hassWSApi.SendRawCommandWithResultAsync(new RawCommandMessage("get_config"));

// Send raw command message with success result
bool success = await hassWSApi.SendRawCommandWithSuccessAsync(new RawCommandMessage("get_config"));