io.pedestal.service.websocket — io.pedestal/pedestal.service 0.8.0-alpha-1

WebSocket support abstracted away from the Servlet API.

InitializeWebSocket clj protocol

Converts a native value (supplied by the network connector) into a WebSocketChannel. Expects the native value to be stored in the Ring request map under key :websocket-channel-source.

initialize-websocket clj

(initialize-websocket source context ws-opts)

Passed the native channel (specific to the network connector), the context, and options.

Performs initialization to initialize a WebSocketChannel, and performs any modification to the context needed, including setting the :websocket-channel key to the WebSocketChannel instance.

start-ws-connection clj

(start-ws-connection ws-channel opts)

Starts a simple WebSocket connection around a WebSocketChannel. The connection allows the server to asyncronously send messages to the client.

Returns a core.async channel used to send messages to the client.

Closing the channel will close the WebSocketChannel.

Writing a value to the channel will send a message to the client. A value is either the message (as a String, ByteBuffer, InputStream, or byte array) or a tuple of the message and a response channel.

When the response channel is provided, the result of sending the message is written to it: Either the keyword :success, :closed, or an Exception thrown when attempting to send the message.

Message delivery is sequential, not parallel.

Options:

:send-buffer-or-n : Used to create the channel, defaults to 10

upgrade-request-to-websocket clj

(upgrade-request-to-websocket context ws-opts)

Initializes a WebSocketChannel for the request stored in the context.

Returns a modified context map.

ws-opts:

:on-open - callback passed the WebSocketChannel and the request map, returns a process object.

:on-close - callback passed the WebSocketChannel, the process object, and the close reason; return value is ignored.

The close reason is a keyword, but the values vary slightly between network connectors.

:on-text callback passed the WebSocketChannel, the process object, and a String; return value is ignored.

:on-binary callback passed the WebSocketChannel, the process object, and the binary data (as a ByteBuffer); return value is ignored.

Note that in order to override the type of binary data passed to the callback, you must make use of [[on-binary]] from your :on-open callback.

websocket-interceptor clj

(websocket-interceptor interceptor-name ws-opts)

Creates and returns an interceptor as a wrapper around upgrade-request-to-websocket.

WebSocketChannel clj protocol

Defines the behavior of an asynchronous WebSocket connection capable of sending and receiving messages.

close! clj

(close! this)

Closes the channel, preventing further sends or receives. Returns nil.

on-binary clj

(on-binary this format callback)

Sets up a callback for received binary messages.

The format may be :bytes, :byte-buffer, or :input-stream.

The callback receives the channel, the process object, and the binary message (in the chosen format). The return value is ignored.

May only be called once. Returns nil.

on-text clj

(on-text this callback)

Sets up a callback for received text messages.

The callback receives the channel, the process object, and message. The return value is ignored.

May only be called once. Returns nil.

send-binary! clj

(send-binary! this data)

Sends the given binary data to the channel as either a byte array or an InputStream.

Returns true on success, false if the channel has closed.

send-text! clj

(send-text! this string)

Sends the given string to the channel as a text frame.

Returns true on success, false if the channel has closed.