[feature] serdes for moved/also_known_as (#2600)

* [feature] serdes for moved/also_known_as

* document `alsoKnownAs` and `movedTo` properties

* only implicitly populate AKA uris from DB for local accounts

* don't let remotes store more than 20 AKA uris to avoid shenanigans

4 files changed, 110 insertions, 2 deletions

diff --git a/internal/typeutils/astointernal.go b/internal/typeutils/astointernal.go
index fa2ae6a62..b262030de 100644
--- a/internal/typeutils/astointernal.go
+++ b/internal/typeutils/astointernal.go
@@ -198,7 +198,25 @@ func (c *Converter) ASRepresentationToAccount(ctx context.Context, accountable a
 
 	// TODO: FeaturedTagsURI
 
-	// TODO: alsoKnownAs
+	// Moved and AlsoKnownAsURIs,
+	// needed for account migrations.
+	movedToURI := ap.GetMovedTo(accountable)
+	if movedToURI != nil {
+		acct.MovedToURI = movedToURI.String()
+	}
+
+	alsoKnownAsURIs := ap.GetAlsoKnownAs(accountable)
+	for i, uri := range alsoKnownAsURIs {
+		// Don't store more than
+		// 20 AKA URIs for remotes,
+		// to prevent people playing
+		// silly buggers.
+		if i >= 20 {
+			break
+		}
+
+		acct.AlsoKnownAsURIs = append(acct.AlsoKnownAsURIs, uri.String())
+	}
 
 	// Extract account public key and verify ownership to account.
 	pkey, pkeyURL, pkeyOwnerID, err := ap.ExtractPublicKey(accountable)
diff --git a/internal/typeutils/astointernal_test.go b/internal/typeutils/astointernal_test.go
index 627f9cac7..fc8cd19a0 100644
--- a/internal/typeutils/astointernal_test.go
+++ b/internal/typeutils/astointernal_test.go
@@ -146,6 +146,7 @@ func (suite *ASToInternalTestSuite) TestParseGargron() {
 	acct, err := suite.typeconverter.ASRepresentationToAccount(context.Background(), rep, "")
 	suite.NoError(err)
 	suite.Equal("https://mastodon.social/inbox", *acct.SharedInboxURI)
+	suite.Equal([]string{"https://tooting.ai/users/Gargron"}, acct.AlsoKnownAsURIs)
 	suite.Equal(int64(1458086400), acct.CreatedAt.Unix())
 }
 
diff --git a/internal/typeutils/internaltoas.go b/internal/typeutils/internaltoas.go
index dc25babaa..a795541d0 100644
--- a/internal/typeutils/internaltoas.go
+++ b/internal/typeutils/internaltoas.go
@@ -171,7 +171,30 @@ func (c *Converter) AccountToAS(ctx context.Context, a *gtsmodel.Account) (vocab
 
 	// alsoKnownAs
 	// Required for Move activity.
-	// TODO: NOT IMPLEMENTED **YET** -- this needs to be added as an activitypub extension to https://github.com/go-fed/activity, see https://github.com/go-fed/activity/tree/master/astool
+	if l := len(a.AlsoKnownAsURIs); l != 0 {
+		alsoKnownAsURIs := make([]*url.URL, l)
+		for i, rawURL := range a.AlsoKnownAsURIs {
+			uri, err := url.Parse(rawURL)
+			if err != nil {
+				return nil, err
+			}
+
+			alsoKnownAsURIs[i] = uri
+		}
+
+		ap.SetAlsoKnownAs(person, alsoKnownAsURIs)
+	}
+
+	// movedTo
+	// Required for Move activity.
+	if a.MovedToURI != "" {
+		movedTo, err := url.Parse(a.MovedToURI)
+		if err != nil {
+			return nil, err
+		}
+
+		ap.SetMovedTo(person, movedTo)
+	}
 
 	// publicKey
 	// Required for signatures.
diff --git a/internal/typeutils/internaltoas_test.go b/internal/typeutils/internaltoas_test.go
index cbeaf3c8c..740938220 100644
--- a/internal/typeutils/internaltoas_test.go
+++ b/internal/typeutils/internaltoas_test.go
@@ -138,6 +138,72 @@ func (suite *InternalToASTestSuite) TestAccountToASWithFields() {
 }`, trimmed)
 }
 
+func (suite *InternalToASTestSuite) TestAccountToASAliasedAndMoved() {
+	testAccount := &gtsmodel.Account{}
+	*testAccount = *suite.testAccounts["local_account_1"] // take zork for this test
+
+	ctx := context.Background()
+
+	// Suppose zork has moved account to turtle.
+	testAccount.AlsoKnownAsURIs = []string{"http://localhost:8080/users/1happyturtle"}
+	testAccount.MovedToURI = "http://localhost:8080/users/1happyturtle"
+	if err := suite.state.DB.UpdateAccount(ctx,
+		testAccount,
+		"also_known_as_uris",
+		"moved_to_uri",
+	); err != nil {
+		suite.FailNow(err.Error())
+	}
+
+	asPerson, err := suite.typeconverter.AccountToAS(context.Background(), testAccount)
+	suite.NoError(err)
+
+	ser, err := ap.Serialize(asPerson)
+	suite.NoError(err)
+
+	bytes, err := json.MarshalIndent(ser, "", "  ")
+	suite.NoError(err)
+
+	// trim off everything up to 'alsoKnownAs';
+	// this is necessary because the order of multiple 'context' entries is not determinate
+	trimmed := strings.Split(string(bytes), "\"alsoKnownAs\"")[1]
+
+	suite.Equal(`: [
+    "http://localhost:8080/users/1happyturtle"
+  ],
+  "discoverable": true,
+  "featured": "http://localhost:8080/users/the_mighty_zork/collections/featured",
+  "followers": "http://localhost:8080/users/the_mighty_zork/followers",
+  "following": "http://localhost:8080/users/the_mighty_zork/following",
+  "icon": {
+    "mediaType": "image/jpeg",
+    "type": "Image",
+    "url": "http://localhost:8080/fileserver/01F8MH1H7YV1Z7D2C8K2730QBF/avatar/original/01F8MH58A357CV5K7R7TJMSH6S.jpg"
+  },
+  "id": "http://localhost:8080/users/the_mighty_zork",
+  "image": {
+    "mediaType": "image/jpeg",
+    "type": "Image",
+    "url": "http://localhost:8080/fileserver/01F8MH1H7YV1Z7D2C8K2730QBF/header/original/01PFPMWK2FF0D9WMHEJHR07C3Q.jpg"
+  },
+  "inbox": "http://localhost:8080/users/the_mighty_zork/inbox",
+  "manuallyApprovesFollowers": false,
+  "movedTo": "http://localhost:8080/users/1happyturtle",
+  "name": "original zork (he/they)",
+  "outbox": "http://localhost:8080/users/the_mighty_zork/outbox",
+  "preferredUsername": "the_mighty_zork",
+  "publicKey": {
+    "id": "http://localhost:8080/users/the_mighty_zork/main-key",
+    "owner": "http://localhost:8080/users/the_mighty_zork",
+    "publicKeyPem": "-----BEGIN PUBLIC KEY-----\nMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAwXTcOAvM1Jiw5Ffpk0qn\nr0cwbNvFe/5zQ+Tp7tumK/ZnT37o7X0FUEXrxNi+dkhmeJ0gsaiN+JQGNUewvpSk\nPIAXKvi908aSfCGjs7bGlJCJCuDuL5d6m7hZnP9rt9fJc70GElPpG0jc9fXwlz7T\nlsPb2ecatmG05Y4jPwdC+oN4MNCv9yQzEvCVMzl76EJaM602kIHC1CISn0rDFmYd\n9rSN7XPlNJw1F6PbpJ/BWQ+pXHKw3OEwNTETAUNYiVGnZU+B7a7bZC9f6/aPbJuV\nt8Qmg+UnDvW1Y8gmfHnxaWG2f5TDBvCHmcYtucIZPLQD4trAozC4ryqlmCWQNKbt\n0wIDAQAB\n-----END PUBLIC KEY-----\n"
+  },
+  "summary": "\u003cp\u003ehey yo this is my profile!\u003c/p\u003e",
+  "tag": [],
+  "type": "Person",
+  "url": "http://localhost:8080/@the_mighty_zork"
+}`, trimmed)
+}
+
 func (suite *InternalToASTestSuite) TestAccountToASWithOneField() {
 	testAccount := &gtsmodel.Account{}
 	*testAccount = *suite.testAccounts["local_account_2"]