Notifications (#34)

Notifications working for:

* Mentions
* Faves
* New follow requests
* New followers

internal/federation/federatingdb/liked.go

@@ -0,0 +1,26 @@
+package federatingdb
+
+import (
+	"context"
+	"net/url"
+
+	"github.com/go-fed/activity/streams/vocab"
+	"github.com/sirupsen/logrus"
+)
+
+// Liked obtains the Liked Collection for an actor with the
+// given id.
+//
+// If modified, the library will then call Update.
+//
+// The library makes this call only after acquiring a lock first.
+func (f *federatingDB) Liked(c context.Context, actorIRI *url.URL) (liked vocab.ActivityStreamsCollection, err error) {
+	l := f.log.WithFields(
+		logrus.Fields{
+			"func":     "Liked",
+			"actorIRI": actorIRI.String(),
+		},
+	)
+	l.Debugf("entering LIKED function with actorIRI %s", actorIRI.String())
+	return nil, nil
+}