[chore] Deinterface processor and subprocessors (#1501)

* [chore] Deinterface processor and subprocessors

* expose subprocessors via function calls

* missing license header

internal/processing/stream/notification.go

@@ -0,0 +1,38 @@
+/*
+   GoToSocial
+   Copyright (C) 2021-2023 GoToSocial Authors admin@gotosocial.org
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Affero General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Affero General Public License for more details.
+
+   You should have received a copy of the GNU Affero General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package stream
+
+import (
+	"encoding/json"
+	"fmt"
+
+	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+	"github.com/superseriousbusiness/gotosocial/internal/stream"
+)
+
+// Notify streams the given notification to any open, appropriate streams belonging to the given account.
+func (p *Processor) Notify(n *apimodel.Notification, account *gtsmodel.Account) error {
+	bytes, err := json.Marshal(n)
+	if err != nil {
+		return fmt.Errorf("error marshalling notification to json: %s", err)
+	}
+
+	return p.toAccount(string(bytes), stream.EventTypeNotification, []string{stream.TimelineNotifications, stream.TimelineHome}, account.ID)
+}