Merge pull request #422 from anyproto/go-5297-push-service-1st-iteration

GO-5297: add FirstMetadataKey function to AclState

commonspace/object/acl/list/aclstate.go

@@ -165,6 +165,13 @@ func (st *AclState) CurrentMetadataKey() (crypto.PubKey, error) {
 	return curKeys.MetadataPubKey, nil
 }
 
+func (st *AclState) FirstMetadataKey() (crypto.PrivKey, error) {
+	if firstKey, ok := st.keys[st.id]; ok && firstKey.MetadataPrivKey != nil {
+		return firstKey.MetadataPrivKey, nil
+	}
+	return nil, ErrNoMetadataKey
+}
+
 func (st *AclState) Keys() map[string]AclKeys {
 	return st.keys
 }

commonspace/object/acl/list/aclstate_test.go

@@ -1,8 +1,11 @@
 package list
 
 import (
+	"crypto/rand"
 	"testing"
 
+	"github.com/anyproto/any-sync/util/crypto"
+
 	"github.com/stretchr/testify/require"
 )
 
@@ -68,3 +71,43 @@ func TestAclStateIsEmpty(t *testing.T) {
 		require.True(t, st.IsEmpty())
 	})
 }
+
+func TestAclState_FirstMetadataKey(t *testing.T) {
+	t.Run("returns first metadata key successfully", func(t *testing.T) {
+		privKey, _, err := crypto.GenerateEd25519Key(rand.Reader)
+		require.NoError(t, err)
+		pubKey := privKey.GetPublic()
+		readKey := crypto.NewAES()
+		state := &AclState{
+			id: "recordId",
+			keys: map[string]AclKeys{
+				"recordId": {
+					ReadKey:         readKey,
+					MetadataPrivKey: privKey,
+					MetadataPubKey:  pubKey,
+				},
+			},
+		}
+		key, err := state.FirstMetadataKey()
+		require.NoError(t, err)
+		require.Equal(t, privKey, key)
+	})
+	t.Run("first metadata is nil", func(t *testing.T) {
+		state := &AclState{
+			id: "recordId",
+			keys: map[string]AclKeys{
+				"recordId": {
+					ReadKey: crypto.NewAES(),
+				},
+			},
+		}
+		key, err := state.FirstMetadataKey()
+		require.ErrorIs(t, err, ErrNoMetadataKey)
+		require.Nil(t, key)
+	})
+	t.Run("returns error when no read key changes", func(t *testing.T) {
+		state := &AclState{}
+		_, err := state.FirstMetadataKey()
+		require.ErrorIs(t, err, ErrNoMetadataKey)
+	})
+}