Tolgee implementation for LocalizationServiceProvider

.clang-format

@@ -32,7 +32,7 @@ BreakBeforeBraces: Custom
 BinPackArguments: false
 BinPackParameters: false
 BreakConstructorInitializers: AfterColon
-ColumnLimit: 200 
+ColumnLimit: 1000 
 IncludeBlocks: Regroup
 IncludeCategories:
   - Regex: '.*\.generated\.h'

Source/Tolgee/Private/Tolgee.cpp

@@ -1,4 +1,4 @@
-// Copyright (c) Tolgee 2022-2023. All Rights Reserved.
+// Copyright (c) Tolgee 2022-2025. All Rights Reserved.
 
 #include "Tolgee.h"
 

Source/Tolgee/Private/TolgeeCdnFetcherSubsystem.cpp

@@ -0,0 +1,118 @@
+// Copyright (c) Tolgee 2022-2025. All Rights Reserved.
+
+#include "TolgeeCdnFetcherSubsystem.h"
+
+#include <HttpModule.h>
+#include <Interfaces/IHttpResponse.h>
+#include <Kismet/KismetInternationalizationLibrary.h>
+
+#include "TolgeeRuntimeSettings.h"
+#include "TolgeeLog.h"
+
+void UTolgeeCdnFetcherSubsystem::OnGameInstanceStart(UGameInstance* GameInstance)
+{
+	const UTolgeeRuntimeSettings* Settings = GetDefault<UTolgeeRuntimeSettings>();
+	if (Settings->CdnAddresses.IsEmpty())
+	{
+		UE_LOG(LogTolgee, Display, TEXT("No CDN addresses configured. Packaged builds will only use static data."));
+		return;
+	}
+	if (GIsEditor && !Settings->bUseCdnInEditor)
+	{
+		UE_LOG(LogTolgee, Display, TEXT("CDN was disabled for editor but it will be used in the final game."));
+		return;
+	}
+
+	FetchAllCdns();
+}
+
+void UTolgeeCdnFetcherSubsystem::OnGameInstanceEnd(bool bIsSimulating)
+{
+	ResetData();
+
+	LastModifiedDates.Empty();
+}
+
+TMap<FString, TArray<FTolgeeTranslationData>> UTolgeeCdnFetcherSubsystem::GetDataToInject() const
+{
+	return CachedTranslations;
+}
+
+void UTolgeeCdnFetcherSubsystem::FetchAllCdns()
+{
+	const UTolgeeRuntimeSettings* Settings = GetDefault<UTolgeeRuntimeSettings>();
+
+	for (const FString& CdnAddress : Settings->CdnAddresses)
+	{
+		TArray<FString> Cultures = UKismetInternationalizationLibrary::GetLocalizedCultures();
+		for (const FString& Culture : Cultures)
+		{
+			const FString DownloadUrl = FString::Printf(TEXT("%s/%s.po"), *CdnAddress, *Culture);
+
+			UE_LOG(LogTolgee, Display, TEXT("Fetching localization data for culture: %s from CDN: %s"), *Culture, *DownloadUrl);
+			FetchFromCdn(Culture, DownloadUrl);
+		}
+	};
+
+}
+
+void UTolgeeCdnFetcherSubsystem::FetchFromCdn(const FString& Culture, const FString& DownloadUrl)
+{
+	const FString* LastModifiedDate = LastModifiedDates.Find(DownloadUrl);
+
+	const FHttpRequestRef HttpRequest = FHttpModule::Get().CreateRequest();
+	HttpRequest->SetVerb("GET");
+	HttpRequest->SetURL(DownloadUrl);
+	HttpRequest->SetHeader(TEXT("accept"), TEXT("application/json"));
+
+	if (LastModifiedDate)
+	{
+		HttpRequest->SetHeader(TEXT("If-Modified-Since"), *LastModifiedDate);
+	}
+
+	HttpRequest->OnProcessRequestComplete().BindUObject(this, &ThisClass::OnFetchedFromCdn, Culture);
+	HttpRequest->ProcessRequest();
+
+	NumRequestsSent++;
+}
+
+void UTolgeeCdnFetcherSubsystem::OnFetchedFromCdn(FHttpRequestPtr Request, FHttpResponsePtr Response, bool bWasSuccessful, FString InCutlure)
+{
+	if (bWasSuccessful && Response.IsValid() && EHttpResponseCodes::IsOk(Response->GetResponseCode()))
+	{
+		UE_LOG(LogTolgee, Display, TEXT("Fetch successfully for %s to %s."), *InCutlure, *Request->GetURL());
+
+		TArray<FTolgeeTranslationData> Translations = ExtractTranslationsFromPO(Response->GetContentAsString());
+		CachedTranslations.Emplace(InCutlure, Translations);
+
+		const FString LastModified = Response->GetHeader(TEXT("Last-Modified"));
+		if (!LastModified.IsEmpty())
+		{
+			LastModifiedDates.Emplace(Request->GetURL(), LastModified);
+		}
+	}
+	else if (Response.IsValid() && Response->GetResponseCode() == EHttpResponseCodes::NotModified)
+	{
+		UE_LOG(LogTolgee, Display, TEXT("No new data for %s to %s."), *InCutlure, *Request->GetURL());
+	}
+	else
+	{
+		UE_LOG(LogTolgee, Error, TEXT("Request for %s to %s failed."), *InCutlure, *Request->GetURL());
+	}
+
+	NumRequestsCompleted++;
+
+	if (NumRequestsCompleted == NumRequestsSent)
+	{
+		UE_LOG(LogTolgee, Display, TEXT("All requests completed. Refreshing translation data."));
+		RefreshTranslationDataAsync();
+	}
+}
+
+void UTolgeeCdnFetcherSubsystem::ResetData()
+{
+	NumRequestsSent = 0;
+	NumRequestsCompleted = 0;
+
+	CachedTranslations.Empty();
+}

Source/Tolgee/Private/TolgeeLocalizationInjectorSubsystem.cpp

@@ -0,0 +1,124 @@
+// Copyright (c) Tolgee 2022-2025. All Rights Reserved.
+
+#include "TolgeeLocalizationInjectorSubsystem.h"
+
+#include <Async/Async.h>
+#include <Engine/World.h>
+#include <Internationalization/TextLocalizationResource.h>
+
+#if WITH_LOCALIZATION_MODULE
+#include <PortableObjectFormatDOM.h>
+#include <PortableObjectPipeline.h>
+#endif
+
+#include "TolgeeLog.h"
+#include "TolgeeTextSource.h"
+
+void UTolgeeLocalizationInjectorSubsystem::OnGameInstanceStart(UGameInstance* GameInstance)
+{
+}
+
+void UTolgeeLocalizationInjectorSubsystem::OnGameInstanceEnd(bool bIsSimulating)
+{
+}
+
+void UTolgeeLocalizationInjectorSubsystem::GetLocalizedResources(const ELocalizationLoadFlags InLoadFlags, TArrayView<const FString> InPrioritizedCultures, FTextLocalizationResource& InOutNativeResource, FTextLocalizationResource& InOutLocalizedResource) const
+{
+	TMap<FString, TArray<FTolgeeTranslationData>> DataToInject = GetDataToInject();
+	for (const TPair<FString, TArray<FTolgeeTranslationData>>& CachedTranslation : DataToInject)
+	{
+		if (!InPrioritizedCultures.Contains(CachedTranslation.Key))
+		{
+			continue;
+		}
+
+		for (const FTolgeeTranslationData& TranslationData : CachedTranslation.Value)
+		{
+			const FTextKey InNamespace = TranslationData.ParsedNamespace;
+			const FTextKey InKey = TranslationData.ParsedKey;
+			const FString InLocalizedString = TranslationData.Translation;
+
+			if (FTextLocalizationResource::FEntry* ExistingEntry = InOutLocalizedResource.Entries.Find(FTextId(InNamespace, InKey)))
+			{
+				//NOTE: -1 is a higher than usual priority, meaning this entry will override any existing one. See FTextLocalizationResource::ShouldReplaceEntry 
+				InOutLocalizedResource.AddEntry(InNamespace, InKey, ExistingEntry->SourceStringHash, InLocalizedString, -1);
+			}
+			else
+			{
+				UE_LOG(LogTolgee, Warning, TEXT("Failed to inject translation for %s:%s. Default entry not found."), *InNamespace.ToString(), *InKey.ToString());
+			}
+		}
+	}
+}
+
+TMap<FString, TArray<FTolgeeTranslationData>> UTolgeeLocalizationInjectorSubsystem::GetDataToInject() const
+{
+	return {};
+}
+
+void UTolgeeLocalizationInjectorSubsystem::Initialize(FSubsystemCollectionBase& Collection)
+{
+	Super::Initialize(Collection);
+
+	TextSource = MakeShared<FTolgeeTextSource>();
+	TextSource->GetLocalizedResources.BindUObject(this, &ThisClass::GetLocalizedResources);
+	FTextLocalizationManager::Get().RegisterTextSource(TextSource.ToSharedRef());
+
+	FWorldDelegates::OnStartGameInstance.AddUObject(this, &ThisClass::OnGameInstanceStart);
+
+#if WITH_EDITOR
+	FEditorDelegates::PrePIEEnded.AddUObject(this, &ThisClass::OnGameInstanceEnd);
+#endif
+}
+
+void UTolgeeLocalizationInjectorSubsystem::RefreshTranslationDataAsync()
+{
+	UE_LOG(LogTolgee, Verbose, TEXT("RefreshTranslationDataAsync requested."));
+
+	AsyncTask(
+		ENamedThreads::AnyHiPriThreadHiPriTask,
+		[=]()
+		{
+			TRACE_CPUPROFILER_EVENT_SCOPE(UTolgeeLocalizationInjectorSubsystem::RefreshResources)
+
+			UE_LOG(LogTolgee, Verbose, TEXT("RefreshTranslationDataAsync executing."));
+
+			FTextLocalizationManager::Get().RefreshResources();
+		}
+	);
+}
+
+TArray<FTolgeeTranslationData> UTolgeeLocalizationInjectorSubsystem::ExtractTranslationsFromPO(const FString& PoContent)
+{
+	TRACE_CPUPROFILER_EVENT_SCOPE(UTolgeeLocalizationInjectorSubsystem::ExtractTranslationsFromPO)
+
+	TArray<FTolgeeTranslationData> Result;
+
+#if WITH_LOCALIZATION_MODULE
+	FPortableObjectFormatDOM PortableObject;
+	PortableObject.FromString(PoContent);
+
+	for (auto EntryPairIter = PortableObject.GetEntriesIterator(); EntryPairIter; ++EntryPairIter)
+	{
+		auto POEntry = EntryPairIter->Value;
+		if (POEntry->MsgId.IsEmpty() || POEntry->MsgStr.Num() == 0 || POEntry->MsgStr[0].IsEmpty())
+		{
+			// We ignore the header entry or entries with no translation.
+			continue;
+		}
+
+		FTolgeeTranslationData TranslationData;
+
+		constexpr ELocalizedTextCollapseMode InTextCollapseMode = ELocalizedTextCollapseMode::IdenticalTextIdAndSource;
+		constexpr EPortableObjectFormat InPOFormat = EPortableObjectFormat::Crowdin;
+
+		PortableObjectPipeline::ParseBasicPOFileEntry(*POEntry, TranslationData.ParsedNamespace, TranslationData.ParsedKey, TranslationData.SourceText, TranslationData.Translation, InTextCollapseMode, InPOFormat);
+
+		Result.Add(TranslationData);
+	}
+#else
+	UE_LOG(LogTolgee, Error, TEXT("Localization module is not available. Cannot extract translations from PO content."));
+#endif
+
+	return Result;
+}