Method handleParameterWebsocket

coderd/parameters.go:131–205

(rw http.ResponseWriter, r *http.Request, initial codersdk.DynamicParametersRequest, render dynamicparameters.Renderer)

}

func (api *API) handleParameterWebsocket(rw http.ResponseWriter, r *http.Request, initial codersdk.DynamicParametersRequest, render dynamicparameters.Renderer) {
	ctx, cancel := context.WithTimeout(r.Context(), 30*time.Minute)
	defer cancel()

	conn, err := websocket.Accept(rw, r, nil)
	if err != nil {
		httpapi.Write(ctx, rw, http.StatusUpgradeRequired, codersdk.Response{
			Message: "Failed to accept WebSocket.",
			Detail:  err.Error(),
		})
		return
	}
	go httpapi.HeartbeatClose(ctx, api.Logger, cancel, conn)

	stream := wsjson.NewStream[codersdk.DynamicParametersRequest, codersdk.DynamicParametersResponse](
		conn,
		websocket.MessageText,
		websocket.MessageText,
		api.Logger,
	)

	// Send an initial form state, computed without any user input.
	result, diagnostics := render.Render(ctx, initial.OwnerID, initial.Inputs)
	response := codersdk.DynamicParametersResponse{
		ID:          -1, // Always start with -1.
		Diagnostics: db2sdk.HCLDiagnostics(diagnostics),
	}
	if result != nil {
		response.Parameters = slice.List(result.Parameters, db2sdk.PreviewParameter)
	}
	err = stream.Send(response)
	if err != nil {
		stream.Drop()
		return
	}

	// As the user types into the form, reprocess the state using their input,
	// and respond with updates.
	updates := stream.Chan()
	ownerID := initial.OwnerID
	for {
		select {
		case <-ctx.Done():
			stream.Close(websocket.StatusGoingAway)
			return
		case update, ok := <-updates:
			if !ok {
				// The connection has been closed, so there is no one to write to
				return
			}

			// Take a nil uuid to mean the previous owner ID.
			// This just removes the need to constantly send who you are.
			if update.OwnerID == uuid.Nil {
				update.OwnerID = ownerID
			}

			ownerID = update.OwnerID