dereference remote media

internal/message/fromfederatorprocess.go

@@ -0,0 +1,145 @@
+/*
+   GoToSocial
+   Copyright (C) 2021 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 message
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/sirupsen/logrus"
+	"github.com/superseriousbusiness/gotosocial/internal/db"
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+	"github.com/superseriousbusiness/gotosocial/internal/transport"
+)
+
+func (p *processor) processFromFederator(federatorMsg gtsmodel.FromFederator) error {
+	l := p.log.WithFields(logrus.Fields{
+		"func":         "processFromFederator",
+		"federatorMsg": fmt.Sprintf("%+v", federatorMsg),
+	})
+
+	l.Debug("entering function PROCESS FROM FEDERATOR")
+
+	switch federatorMsg.APObjectType {
+	case gtsmodel.ActivityStreamsNote:
+
+		incomingStatus, ok := federatorMsg.GTSModel.(*gtsmodel.Status)
+		if !ok {
+			return errors.New("note was not parseable as *gtsmodel.Status")
+		}
+
+		l.Debug("will now derefence incoming status")
+		if err := p.dereferenceStatusFields(incomingStatus); err != nil {
+			return fmt.Errorf("error dereferencing status from federator: %s", err)
+		}
+		if err := p.db.UpdateByID(incomingStatus.ID, incomingStatus); err != nil {
+			return fmt.Errorf("error updating dereferenced status in the db: %s", err)
+		}
+
+		if err := p.notifyStatus(incomingStatus); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// dereferenceStatusFields fetches all the information we temporarily pinned to an incoming
+// federated status, back in the federating db's Create function.
+//
+// When a status comes in from the federation API, there are certain fields that
+// haven't been dereferenced yet, because we needed to provide a snappy synchronous
+// response to the caller. By the time it reaches this function though, it's being
+// processed asynchronously, so we have all the time in the world to fetch the various
+// bits and bobs that are attached to the status, and properly flesh it out, before we
+// send the status to any timelines and notify people.
+//
+// Things to dereference and fetch here:
+//
+// 1. Media attachments.
+// 2. Hashtags.
+// 3. Emojis.
+// 4. Mentions.
+// 5. Posting account.
+// 6. Replied-to-status.
+//
+// SIDE EFFECTS:
+// This function will deference all of the above, insert them in the database as necessary,
+// and attach them to the status. The status itself will not be added to the database yet,
+// that's up the caller to do.
+func (p *processor) dereferenceStatusFields(status *gtsmodel.Status) error {
+	l := p.log.WithFields(logrus.Fields{
+		"func": "dereferenceStatusFields",
+		"status": fmt.Sprintf("%+v", status),
+	})
+	l.Debug("entering function")
+
+	var t transport.Transport
+	var err error
+	var username string
+	// TODO: dereference with a user that's addressed by the status
+	t, err = p.federator.GetTransportForUser(username)
+	if err != nil {
+		return fmt.Errorf("error creating transport: %s", err)
+	}
+
+	// 1. Media attachments.
+	//
+	// At this point we should know:
+	// * the media type of the file we're looking for (a.File.ContentType)
+	// * the blurhash (a.Blurhash)
+	// * the file type (a.Type)
+	// * the remote URL (a.RemoteURL)
+	// This should be enough to pass along to the media processor.
+	attachmentIDs := []string{}
+	for _, a := range status.GTSMediaAttachments {
+		l.Debug("dereferencing attachment: %+v", a)
+
+		// it might have been processed elsewhere so check first if it's already in the database or not
+		maybeAttachment := &gtsmodel.MediaAttachment{}
+		err := p.db.GetWhere("remote_url", a.RemoteURL, maybeAttachment)
+		if err == nil {
+			// we already have it in the db, dereferenced, no need to do it again
+			l.Debugf("attachment already exists with id %s", maybeAttachment.ID)
+			attachmentIDs = append(attachmentIDs, maybeAttachment.ID)
+			continue
+		}
+		if _, ok := err.(db.ErrNoEntries); !ok {
+			// we have a real error
+			return fmt.Errorf("error checking db for existence of attachment with remote url %s: %s", a.RemoteURL, err)
+		}
+		// it just doesn't exist yet so carry on
+		l.Debug("attachment doesn't exist yet, calling ProcessRemoteAttachment", a)
+		deferencedAttachment, err := p.mediaHandler.ProcessRemoteAttachment(t, a, status.AccountID)
+		if err != nil {
+			p.log.Errorf("error dereferencing status attachment: %s", err)
+			continue
+		}
+		l.Debugf("dereferenced attachment: %+v", deferencedAttachment)
+		deferencedAttachment.StatusID = deferencedAttachment.ID
+		if err := p.db.Put(deferencedAttachment); err != nil {
+			return fmt.Errorf("error inserting dereferenced attachment with remote url %s: %s", a.RemoteURL, err)
+		}
+		deferencedAttachment.Description = a.Description
+		attachmentIDs = append(attachmentIDs, deferencedAttachment.ID)
+	}
+	status.Attachments = attachmentIDs
+
+	return nil
+}