Added actor Json marshal

actor.go

@@ -1,6 +1,7 @@
 package activitypub
 
 import (
+	"bytes"
 	"errors"
 	"github.com/buger/jsonparser"
 	"time"
@@ -209,6 +210,36 @@ func (p *PublicKey) UnmarshalJSON(data []byte) error {
 	}
 	return nil
 }
+
+func (p PublicKey) MarshalJSON() ([]byte, error) {
+	b := bytes.Buffer{}
+	writeComma := func() { b.WriteString(",") }
+	writeCommaIfNotEmpty := func(notEmpty bool) {
+		if notEmpty {
+			writeComma()
+		}
+	}
+	notEmpty := true
+	b.Write([]byte{'{'})
+	if v, err := p.ID.MarshalJSON(); err == nil && len(v) > 0 {
+		notEmpty = !writeProp(&b, "id", v)
+	}
+	if p.Owner != nil {
+		writeCommaIfNotEmpty(notEmpty)
+		notEmpty = writeIRIProp(&b, "owner", p.Owner) || notEmpty
+	}
+	if len(p.PublicKeyPem) > 0 {
+		writeCommaIfNotEmpty(notEmpty)
+		notEmpty = writeIRIProp(&b, "publicKeyPem", p.Owner) || notEmpty
+	}
+
+	if notEmpty {
+		b.Write([]byte{'}'})
+		return b.Bytes(), nil
+	}
+	return nil, nil
+}
+
 type (
 	// Application describes a software application.
 	Application = Actor
@@ -364,6 +395,65 @@ func (a *Actor) UnmarshalJSON(data []byte) error {
 	return nil
 }
 
+func (a Actor) MarshalJSON() ([]byte, error) {
+	b := bytes.Buffer{}
+	notEmpty := false
+	b.Write([]byte{'{'})
+
+	OnObject(a, func(o *Object) error {
+		notEmpty = writeObject(&b, *o)
+		return nil
+	})
+	writeComma := func() { b.WriteString(",") }
+	writeCommaIfNotEmpty := func(notEmpty bool) {
+		if notEmpty {
+			writeComma()
+		}
+	}
+	if a.Inbox != nil {
+		writeCommaIfNotEmpty(notEmpty)
+		notEmpty = writeItemProp(&b, "inbox", a.Inbox) || notEmpty
+	}
+	if a.Outbox != nil {
+		writeCommaIfNotEmpty(notEmpty)
+		notEmpty = writeItemProp(&b, "outbox", a.Outbox) || notEmpty
+	}
+	if a.Following != nil {
+		writeCommaIfNotEmpty(notEmpty)
+		notEmpty = writeItemProp(&b, "following", a.Following) || notEmpty
+	}
+	if a.Followers != nil {
+		writeCommaIfNotEmpty(notEmpty)
+		notEmpty = writeItemProp(&b, "followers", a.Followers) || notEmpty
+	}
+	if a.Liked != nil {
+		writeCommaIfNotEmpty(notEmpty)
+		notEmpty = writeItemProp(&b, "liked", a.Liked) || notEmpty
+	}
+	if a.Endpoints != nil {
+		writeCommaIfNotEmpty(notEmpty)
+		if v, err := a.Endpoints.MarshalJSON(); err == nil && len(v) > 0 {
+			notEmpty = writeProp(&b, "endpoints", v) || notEmpty
+		}
+	}
+	if len(a.Streams) > 0 {
+		writeCommaIfNotEmpty(notEmpty)
+		writePropName(&b, "streams")
+		lNotEmpty := true
+		for _, ss := range a.Streams {
+			writeCommaIfNotEmpty(lNotEmpty)
+			lNotEmpty = writeItemCollection(&b, ss) || lNotEmpty
+		}
+		notEmpty = lNotEmpty || notEmpty
+	}
+
+	if notEmpty {
+		b.Write([]byte{'}'})
+		return b.Bytes(), nil
+	}
+	return nil, nil
+}
+
 // Endpoints a json object which maps additional (typically server/domain-wide)
 // endpoints which may be useful either for this actor or someone referencing this actor.
 // This mapping may be nested inside the actor document as the value or may be a link to
@@ -402,6 +492,49 @@ func (e *Endpoints) UnmarshalJSON(data []byte) error {
 	return nil
 }
 
+// MarshalJSON
+func (e Endpoints) MarshalJSON() ([]byte, error) {
+	b := bytes.Buffer{}
+	notEmpty := false
+
+	writeComma := func() { b.WriteString(",") }
+	writeCommaIfNotEmpty := func(notEmpty bool) {
+		if notEmpty {
+			writeComma()
+		}
+	}
+	b.Write([]byte{'{'})
+	if e.OauthAuthorizationEndpoint != nil {
+		writeCommaIfNotEmpty(notEmpty)
+		notEmpty = writeItemProp(&b, "oauthAuthorizationEndpoint", e.OauthAuthorizationEndpoint) || notEmpty
+	}
+	if e.OauthTokenEndpoint != nil {
+		writeCommaIfNotEmpty(notEmpty)
+		notEmpty = writeItemProp(&b, "oauthTokenEndpoint", e.OauthTokenEndpoint) || notEmpty
+	}
+	if e.ProvideClientKey != nil {
+		writeCommaIfNotEmpty(notEmpty)
+		notEmpty = writeItemProp(&b, "provideClientKey", e.ProvideClientKey) || notEmpty
+	}
+	if e.SignClientKey != nil {
+		writeCommaIfNotEmpty(notEmpty)
+		notEmpty = writeItemProp(&b, "signClientKey", e.SignClientKey) || notEmpty
+	}
+	if e.SharedInbox != nil {
+		writeCommaIfNotEmpty(notEmpty)
+		notEmpty = writeItemProp(&b, "sharedInbox", e.SharedInbox) || notEmpty
+	}
+	if e.UploadMedia != nil {
+		writeCommaIfNotEmpty(notEmpty)
+		notEmpty = writeItemProp(&b, "uploadMedia", e.UploadMedia) || notEmpty
+	}
+	if notEmpty {
+		b.Write([]byte{'}'})
+		return b.Bytes(), nil
+	}
+	return nil, nil
+}
+
 // ToActor
 func ToActor(it Item) (*Actor, error) {
 	switch i := it.(type) {
@@ -410,6 +543,8 @@ func ToActor(it Item) (*Actor, error) {
 	case Actor:
 		return &i, nil
 	case *Object:
+		// TODO(marius): this is unsafe as Actor has a different memory layout than Actor
+		//  Everything should be fine as long as you don't try to read the Actor specific collections
 		return (*Actor)(unsafe.Pointer(i)), nil
 	case Object:
 		return (*Actor)(unsafe.Pointer(&i)), nil

encoding.go

@@ -46,6 +46,9 @@ func writeNaturalLanguageProp(b *bytes.Buffer, n string, nl NaturalLanguageValue
 func writeBoolProp(b *bytes.Buffer, n string, t bool) (notEmpty bool) {
 	return writeProp(b, n, []byte(fmt.Sprintf("%t", t)))
 }
+func writeIntProp(b *bytes.Buffer, n string, d int) (notEmpty bool) {
+	return writeProp(b, n, []byte(fmt.Sprintf("%d", d)))
+}
 func writeTimeProp(b *bytes.Buffer, n string, t time.Time) (notEmpty bool) {
 	if v, err := t.MarshalJSON(); err == nil {
 		return writeProp(b, n, v)
@@ -94,11 +97,20 @@ func writeItemProp(b *bytes.Buffer, n string, i Item) (notEmpty bool) {
 	return notEmpty
 }
 
-func writeItemCollectionProp(b *bytes.Buffer, n string, col ItemCollection) (notEmpty bool) {
+func writeString(b *bytes.Buffer, s string) (notEmpty bool) {
+	if len(s) == 0 {
+		return false
+	}
+	b.Write([]byte{'"'})
+	b.WriteString(s)
+	b.Write([]byte{'"'})
+	return true
+}
+
+func writeItemCollection(b *bytes.Buffer, col ItemCollection) (notEmpty bool) {
 	if len(col) == 0 {
 		return notEmpty
 	}
-	writePropName(b, n)
 	writeComma := func() { b.WriteString(",") }
 	writeCommaIfNotEmpty := func(notEmpty bool) {
 		if notEmpty {
@@ -125,6 +137,13 @@ func writeItemCollectionProp(b *bytes.Buffer, n string, col ItemCollection) (not
 	b.Write([]byte{']'})
 	return notEmpty
 }
+func writeItemCollectionProp(b *bytes.Buffer, n string, col ItemCollection) (notEmpty bool) {
+	if len(col) == 0 {
+		return notEmpty
+	}
+	writePropName(b, n)
+	return writeItemCollection(b, col)
+}
 
 func writeObject(b *bytes.Buffer, o Object) (notEmpty bool) {
 	writeComma := func() { b.WriteString(",") }

object.go

@@ -112,9 +112,7 @@ func (a ActivityVocabularyType) MarshalJSON() ([]byte, error) {
 		return nil, nil
 	}
 	b := bytes.Buffer{}
-	b.Write([]byte{'"'})
-	b.WriteString(string(a))
-	b.Write([]byte{'"'})
+	writeString(&b, string(a))
 	return b.Bytes(), nil
 }
 
@@ -374,14 +372,12 @@ func (c *MimeType) UnmarshalJSON(data []byte) error {
 }
 
 // MarshalJSON
-func (c MimeType) MarshalJSON() ([]byte, error) {
-	if len(c) == 0 {
+func (m MimeType) MarshalJSON() ([]byte, error) {
+	if len(m) == 0 {
 		return nil, nil
 	}
 	b := bytes.Buffer{}
-	b.Write([]byte{'"'})
-	b.WriteString(string(c))
-	b.Write([]byte{'"'})
+	writeString(&b, string(m))
 	return b.Bytes(), nil
 }