Web socket client

Connects to a remote WebSocket server, sends every input record as a message and emits every message received from the server. One connection per component, kept open while the flow runs.

Pins

Pin	Kind	Types	Description
Input	input	Viaducta.Plugins.Http.Types.WebSocketMessage, Viaducta.Plugins.TextPlugin.Types.TextRecord	Message to send. Connects first if needed.
Output	output	Viaducta.Plugins.Http.Types.WebSocketMessage	Called for every message received from the server.
Start	start		Opens the connection. Called by the system at flow start when unconnected.
OnConnect	on connect	Viaducta.Plugins.Http.Types.WebSocketMessage	Called (with an empty message) after each successful (re)connect, e.g. to send a subscribe message.

Configuration

Field	Type	Default	Description
Uri	string		Server URL, ws://host:port/path or wss://....
AuthType	dropdown: 0 None, 1 Basic, 2 Digest, 3 NTLM, 4 Bearer, 5 Jwt, 6 OAuth1, 7 OAuth2, 8 Other, 9 ClientCertificate	0	Authentication of the opening HTTP handshake.
Domain	string		Windows domain (AuthType 3).
Username	string		User name (AuthType 1, 2, 3).
Password	password		Password (AuthType 1, 2, 3).
Bearer	string		Written as-is into the Authorization header (AuthType 4, 5, 7), so include the scheme: Bearer eyJ....
ConsumerKey	string		OAuth 1.0a consumer key (AuthType 6), signed as GET on Uri.
ConsumerSecret	string		OAuth 1.0a consumer secret (AuthType 6).
AccessToken	string		OAuth 1.0a access token (AuthType 6).
TokenSecret	string		OAuth 1.0a token secret (AuthType 6).
Authorization	string		Complete Authorization header value (AuthType 8).
ClientCertificate	certificate		Name of a certificate object in the repository (AuthType 9).
MaxMessageSize	integer	1048576	Max size of a received message in bytes.
IgnoreCertificate	boolean	false	Broken, see Notes. Leave false.
Headers	dictionary (JSON object)		Headers for the opening handshake only, e.g. {"X-Client":"viaducta"}.
TimeOutMs	integer	30000	Ignored.

Behaviour

• The connection is opened on Start or on the first input. If it is closed (by the server or a network error), the next input or Start call reconnects; there is no automatic reconnect in between.
• Sending: TextRecord → text message with Value. WebSocketMessage → ContentByte is sent if set, otherwise ContentString (UTF-8); MessageType 0 = text, 1 = binary. Sends are serialized.
• Receiving: each complete message is emitted on Output with ContentByte, ContentString (UTF-8 decoding of the bytes), MessageType and SessionId (a random id of this component instance, not from the server). Each message gets new, empty metadata, so responses can't be correlated to the input record via metadata.
• A message bigger than MaxMessageSize closes the connection (MessageTooBig). The plugin keeps the flow running and closes the socket when the flow stops.

Notes

• IgnoreCertificate = true makes every wss:// connection fail: the code rejects all server certificates instead of accepting them.
• TimeOutMs is not used; connect and send have no timeout of their own.
• When forwarding a received WebSocketMessage with a changed ContentString, clear ContentByte, otherwise the old bytes are sent.
• Errors while processing received messages are only logged.

Example

{ "Uri": "wss://stream.example.com/ws", "AuthType": 4, "Bearer": "=Secrets.StreamToken" }

Script (subscribe message) → Web socket client (OnConnect → Script) → Output → Json deserializer → ...