Method prepare

coderd/notifications/notifier.go:227–261

prepare has two roles: 1. render the title & body templates 2. build a dispatcher from the given message, payload, and these templates - to be used for delivering the notification

(ctx context.Context, msg database.AcquireNotificationMessagesRow)

// 1. render the title & body templates
// 2. build a dispatcher from the given message, payload, and these templates - to be used for delivering the notification
func (n *notifier) prepare(ctx context.Context, msg database.AcquireNotificationMessagesRow) (dispatch.DeliveryFunc, error) {
	select {
	case <-ctx.Done():
		return nil, ctx.Err()
	default:
	}

	// NOTE: when we change the format of the MessagePayload, we have to bump its version and handle unmarshalling
	// differently here based on that version.
	var payload types.MessagePayload
	err := json.Unmarshal(msg.Payload, &payload)
	if err != nil {
		return nil, xerrors.Errorf("unmarshal payload: %w", err)
	}

	handler, ok := n.handlers[msg.Method]
	if !ok {
		return nil, xerrors.Errorf("failed to resolve handler %q", msg.Method)
	}

	helpers, err := n.fetchHelpers(ctx)
	if err != nil {
		return nil, decorateHelpersError{err}
	}

	var title, body string
	if title, err = render.GoTemplate(msg.TitleTemplate, payload, helpers); err != nil {
		return nil, xerrors.Errorf("render title: %w", err)
	}
	if body, err = render.GoTemplate(msg.BodyTemplate, payload, helpers); err != nil {
		return nil, xerrors.Errorf("render body: %w", err)
	}

	return handler.Dispatcher(payload, title, body, helpers)
}

// deliver sends a given notification message via its defined method.
// This method *only* returns an error when a context error occurs; any other error is interpreted as a failure to