From d33a2440d71d662c851d31ee96335e860f994a00 Mon Sep 17 00:00:00 2001
From: Wessie <github@wessie.info>
Date: Wed, 19 Jun 2024 23:26:35 +0100
Subject: [PATCH] rpc: make helpers handle empty-values for some types

Turns out that protobuf does not send actual nils to handlers if the
request is empty, but always atleast allocates the zero value of said
type before the call. We check for some "required" fields now to determine
if we should return nil or not from the helper
---
 rpc/helpers.go      | 6 +++---
 rpc/helpers_test.go | 8 ++++++--
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/rpc/helpers.go b/rpc/helpers.go
index cf70e40..e905582 100644
--- a/rpc/helpers.go
+++ b/rpc/helpers.go
@@ -174,7 +174,7 @@ func toProtoSongUpdate(s *radio.SongUpdate) *SongUpdate {
 }
 
 func fromProtoSongUpdate(s *SongUpdate) *radio.SongUpdate {
-	if s == nil {
+	if s == nil || (s.Song == nil && s.Info == nil) {
 		return nil
 	}
 	return &radio.SongUpdate{
@@ -214,7 +214,7 @@ func toProtoQueueID(rid radio.QueueID) *QueueID {
 }
 
 func fromProtoQueueID(id *QueueID) radio.QueueID {
-	if id == nil {
+	if id == nil || len(id.ID) == 0 {
 		return radio.QueueID{}
 	}
 
@@ -276,7 +276,7 @@ func toProtoUser(u *radio.User) *User {
 }
 
 func fromProtoUser(u *User) *radio.User {
-	if u == nil {
+	if u == nil || (u.Id == 0 && u.Username == "") {
 		return nil
 	}
 	return &radio.User{
diff --git a/rpc/helpers_test.go b/rpc/helpers_test.go
index 315604f..b78930f 100644
--- a/rpc/helpers_test.go
+++ b/rpc/helpers_test.go
@@ -17,7 +17,7 @@ func TestRoundtrip(tt *testing.T) {
 	// special generator for users since we don't actually pass all the fields
 	// over the wire for reasons
 	userGen := gen.Struct(reflect.TypeFor[radio.User](), map[string]gopter.Gen{
-		"ID":              a.GenForType(reflect.TypeFor[radio.UserID]()),
+		"ID":              a.GenForType(reflect.TypeFor[radio.UserID]()).SuchThat(func(v radio.UserID) bool { return v > 0 }),
 		"Username":        gen.AnyString(),
 		"IP":              gen.AnyString(),
 		"UpdatedAt":       a.GenForType(reflect.TypeFor[*time.Time]()),
@@ -95,7 +95,11 @@ func TestRoundtrip(tt *testing.T) {
 	p.Property("user-permissions", a.ForAll(func(in radio.UserPermissions) bool {
 		out := fromProtoUserPermissions(toProtoUserPermissions(in))
 
-		return assert.Equal(tt, in, out)
+		if len(in) == 0 {
+			return assert.Len(tt, out, 0)
+		} else {
+			return assert.Equal(tt, in, out)
+		}
 	}))
 	p.Property("dj", a.ForAll(func(in radio.DJ) bool {
 		out := fromProtoDJ(toProtoDJ(in))