speechmatics.client

Wrapper library to interface with Real-time ASR v2 API. Based on http://asyncio.readthedocs.io/en/latest/producer_consumer.html

class speechmatics.client.WebsocketClient(connection_settings)[source]

Manage a transcription session with the server.

The best way to interact with this library is to instantiate this client and then add a set of handlers to it. Handlers respond to particular types of messages received from the server.

Parameters

connection_settings (speechmatics.models.ConnectionSettings) – Settings for the WebSocket connection, including the URL of the server.

add_event_handler(event_name, event_handler)[source]

Add an event handler (callback function) to handle an incoming message from the server. Event handlers are passed a copy of the incoming message from the server. If event_name is set to ‘all’ then the handler will be added for every event.

For example, a simple handler that just prints out the speechmatics.models.ServerMessageType.AddTranscript messages received:

>>> client = WebsocketClient(
        ConnectionSettings(url="wss://localhost:9000"))
>>> handler = lambda msg: print(msg)
>>> client.add_event_handler(ServerMessageType.AddTranscript, handler)
Parameters
  • event_name (str) – The name of the message for which a handler is being added. Refer to speechmatics.models.ServerMessageType for a list of the possible message types.

  • event_handler (Callable[[dict], None]) – A function to be called when a message of the given type is received.

Raises

ValueError – If the given event name is not valid.

add_middleware(event_name, middleware)[source]

Add a middleware to handle outgoing messages sent to the server. Middlewares are passed a reference to the outgoing message, which they may alter. If event_name is set to ‘all’ then the handler will be added for every event.

Parameters
  • event_name (str) – The name of the message for which a middleware is being added. Refer to the V2 API docs for a list of the possible message types.

  • middleware (Callable[[dict, bool], None]) – A function to be called to process an outgoing message of the given type. The function receives the message as the first argument and a second, boolean argument indicating whether or not the message is binary data (which implies it is an AddAudio message).

Raises

ValueError – If the given event name is not valid.

get_language_pack_info() dict[source]

Get the language_pack_info which is a subset of information from the manifest in the language pack which we expose to end users.

Can be None if this field has not yet been set - i.e. if the RecognitionStarted message has not been received yet.

async run(stream, transcription_config, audio_settings)[source]

Begin a new recognition session. This will run asynchronously. Most callers may prefer to use run_synchronously() which will block until the session is finished.

Parameters
Raises

Exception – Can raise any exception returned by the consumer/producer tasks.

run_synchronously(*args, timeout=None, **kwargs)[source]

Run the transcription synchronously. :raises asyncio.TimeoutError: If the given timeout is exceeded.

stop()[source]

Indicates that the recognition session should be forcefully stopped. Only used in conjunction with run. You probably don’t need to call this if you’re running the client via run_synchronously().

update_transcription_config(new_transcription_config)[source]

Updates the transcription config used for the session. This results in a SetRecognitionConfig message sent to the server.

Parameters

new_transcription_config (speechmatics.models.TranscriptionConfig) – The new config object.