Firebase Dynamic Links on Unity iOS says "Deep Link does not contain valid required params" - ios

Question

I'm using Firebase Dynamic Links for Unity, and I've got it working well with Android. I've even got a solution for Desktop, where the fallback link takes users to a webpage where I can provide instructions to the user for how to get their link content on Desktop.
On iOS, however, I always get errors like this when trying dynamic links:
[Firebase/Analytics][I-ACS023001] Deep Link does not contain valid required params. URL params: {
"_cpb" = 1;
"_cpt" = cpit;
"_fpb" = "CIAIEIAGGgVlbi11cw==";
"_iipp" = 1;
"_iumchkactval" = 1;
"_iumenbl" = 1;
"_osl" = "https://cgs.link/zu_tiles_hime?_iipp=1";
"_plt" = 260;
"_uit" = 1064;
apn = "com.finoldigital.cardgamesim";
cid = 8062347334713659136;
ibi = "com.finoldigital.CardGameSim";
isi = 1392877362;
link = "https://www.cardgamesimulator.com/link%%3Furl%%3Dhttps://www.cardgamesimulator.com/games/zu_tiles_hime/zu_tiles_hime.json";
sd = "Play Zu Tile: Hime on CGS!";
si = "https://www.cardgamesimulator.com/games/zu_tiles_hime/Banner.png";
st = "Card Game Simulator - Zu Tiles: Hime";
}
I saw in another issue that it could be because of ?, =, and & symbols in the link, so I url-encoded those, but I am still getting the same error.
For reference, my code for iOS is effectively:
private void Start()
{
FirebaseApp.CheckAndFixDependenciesAsync().ContinueWithOnMainThread(task =>
{
var dependencyStatus = task.Result;
if (dependencyStatus != DependencyStatus.Available)
{
Debug.LogError("Could not resolve all Firebase dependencies: " + dependencyStatus);
return;
}
DynamicLinks.DynamicLinkReceived += OnDynamicLinkReceived;
});
}
I immediately log in OnDynamicLinkReceived, so this callback is clearly never happening. Does anybody know what I am doing wrong, or what I could do to get the dynamic link received callback?

Answer 1

For anyone who runs into the same issue:
I solved this by modifying my build script to add the values for FirebaseDynamicLinksCustomDomains and FirebaseAppDelegateProxyEnabled to Info.plist as part of my build process.
PostProcess code:
var pbxProjectPath = PBXProject.GetPBXProjectPath(buildPath);
var pbxProject = new PBXProject(); pbxProject.ReadFromFile(pbxProjectPath);
const string targetName = "Unity-iPhone"; var targetGuid = pbxProject.GetUnityMainTargetGuid();
var src = AssetDatabase.GetAssetPath(file);
var fileName = Path.GetFileName(src);
var dst = buildPath + "/" + targetName + "/" + fileName;
if (!File.Exists(dst)) FileUtil.CopyFileOrDirectory(src, dst); pbxProject.AddFile(targetName + "/" + fileName, fileName);
pbxProject.AddBuildProperty(targetGuid, "CODE_SIGN_ENTITLEMENTS", targetName + "/" + fileName);
pbxProject.WriteToFile(pbxProjectPath);
var plistPath = buildPath + "/Info.plist";
var plistDocument = new PlistDocument(); plistDocument.ReadFromString(File.ReadAllText(plistPath));
var rootDict = plistDocument.root;
rootDict.SetBoolean("FirebaseAppDelegateProxyEnabled", false);
PlistElementArray customDomains = rootDict.CreateArray("FirebaseDynamicLinksCustomDomains");
customDomains.AddString("https://cgs.link");
File.WriteAllText(plistPath);