Read platform kernel blob from asset directory instead of FLX

assets/directory_asset_bundle.h

@@ -19,9 +19,9 @@ class DirectoryAssetBundle {
 
   bool GetAsBuffer(const std::string& asset_name, std::vector<uint8_t>* data);
 
- private:
   std::string GetPathForAsset(const std::string& asset_name);
 
+ private:
   const std::string directory_;
 
   FXL_DISALLOW_COPY_AND_ASSIGN(DirectoryAssetBundle);

runtime/dart_init.cc

@@ -14,6 +14,7 @@
 #include <utility>
 #include <vector>
 
+#include "flutter/assets/directory_asset_bundle.h"
 #include "flutter/assets/unzipper_provider.h"
 #include "flutter/assets/zip_asset_store.h"
 #include "flutter/common/settings.h"
@@ -27,6 +28,7 @@
 #include "flutter/runtime/start_up.h"
 #include "lib/fxl/arraysize.h"
 #include "lib/fxl/build_config.h"
+#include "lib/fxl/files/path.h"
 #include "lib/fxl/logging.h"
 #include "lib/fxl/time/time_delta.h"
 #include "lib/tonic/converter/dart_converter.h"
@@ -265,6 +267,16 @@ Dart_Isolate ServiceIsolateCreateCallback(const char* script_uri,
 #endif  // FLUTTER_RUNTIME_MODE
 }
 
+static bool GetAssetAsBuffer(
+    const std::string& name,
+    std::vector<uint8_t>* data,
+    std::unique_ptr<DirectoryAssetBundle>& directory_asset_bundle,
+    fxl::RefPtr<ZipAssetStore>& asset_store) {
+  return (directory_asset_bundle &&
+          directory_asset_bundle->GetAsBuffer(name, data)) ||
+         (asset_store && asset_store->GetAsBuffer(name, data));
+}
+
 Dart_Isolate IsolateCreateCallback(const char* script_uri,
                                    const char* main,
                                    const char* package_root,
@@ -296,11 +308,30 @@ Dart_Isolate IsolateCreateCallback(const char* script_uri,
     if (!running_from_source) {
       // Attempt to copy the snapshot from the asset bundle.
       const std::string& bundle_path = entry_path;
-      fxl::RefPtr<ZipAssetStore> zip_asset_store =
-          fxl::MakeRefCounted<ZipAssetStore>(
-              GetUnzipperProviderForPath(std::move(bundle_path)));
-      zip_asset_store->GetAsBuffer(kKernelAssetKey, &kernel_data);
-      zip_asset_store->GetAsBuffer(kSnapshotAssetKey, &snapshot_data);
+
+      struct stat stat_result = {};
+      if (::stat(bundle_path.c_str(), &stat_result) == 0) {
+        std::unique_ptr<DirectoryAssetBundle> directory_asset_bundle;
+        // TODO(zarah): Remove usage of zip_asset_store once app.flx is removed.
+        fxl::RefPtr<ZipAssetStore> zip_asset_store;
+        // bundle_path is either the path to app.flx or the flutter assets
+        // directory.
+        std::string flx_path = bundle_path;
+        if (S_ISDIR(stat_result.st_mode)) {
+          directory_asset_bundle =
+              std::make_unique<DirectoryAssetBundle>(bundle_path);
+          flx_path = files::GetDirectoryName(bundle_path) + "/app.flx";
+        }
+
+        if (access(flx_path.c_str(), R_OK) == 0) {
+          zip_asset_store = fxl::MakeRefCounted<ZipAssetStore>(
+              GetUnzipperProviderForPath(flx_path));
+        }
+        GetAssetAsBuffer(kKernelAssetKey, &kernel_data, directory_asset_bundle,
+                         zip_asset_store);
+        GetAssetAsBuffer(kSnapshotAssetKey, &snapshot_data,
+                         directory_asset_bundle, zip_asset_store);
+      }
     }
   }
 
@@ -561,9 +592,10 @@ void InitDartVM(const uint8_t* vm_snapshot_data,
 #endif
 
   if (!bundle_path.empty()) {
-    auto zip_asset_store = fxl::MakeRefCounted<ZipAssetStore>(
-        GetUnzipperProviderForPath(std::move(bundle_path)));
-    zip_asset_store->GetAsBuffer(kPlatformKernelAssetKey, &platform_data);
+    std::unique_ptr<DirectoryAssetBundle> directory_asset_bundle =
+        std::make_unique<DirectoryAssetBundle>(bundle_path);
+    directory_asset_bundle->GetAsBuffer(kPlatformKernelAssetKey,
+                                        &platform_data);
     if (!platform_data.empty()) {
       kernel_platform = Dart_ReadKernelBinary(
           platform_data.data(), platform_data.size(), ReleaseFetchedBytes);

runtime/dart_init.h

@@ -15,13 +15,13 @@
 
 namespace blink {
 
-// Name of the kernel blob asset within the FLX bundle.
+// Name of the kernel blob asset within the asset directory.
 extern const char kKernelAssetKey[];
 
-// Name of the snapshot blob asset within the FLX bundle.
+// Name of the snapshot blob asset within the asset directory.
 extern const char kSnapshotAssetKey[];
 
-// Name of the platform kernel blob asset within the FLX bundle.
+// Name of the platform kernel blob asset within the asset directory.
 extern const char kPlatformKernelAssetKey[];
 
 bool IsRunningPrecompiledCode();

shell/common/engine.cc

@@ -201,9 +201,17 @@ void Engine::Init(const std::string& bundle_path) {
 #error Unknown OS
 #endif
 
+  std::string flx_path = bundle_path;
+  struct stat stat_result = {};
+  if (::stat(flx_path.c_str(), &stat_result) == 0) {
+    if (S_ISDIR(stat_result.st_mode)) {
+      flx_path = files::GetDirectoryName(bundle_path) + "/app.flx";
+    }
+  }
+
   blink::InitRuntime(vm_snapshot_data, vm_snapshot_instr,
                      default_isolate_snapshot_data,
-                     default_isolate_snapshot_instr, bundle_path);
+                     default_isolate_snapshot_instr, flx_path);
 }
 
 const std::string Engine::main_entrypoint_ = "main";
@@ -485,18 +493,18 @@ void Engine::ConfigureAssetBundle(const std::string& path) {
     return;
   }
 
+  std::string flx_path;
   if (S_ISDIR(stat_result.st_mode)) {
     directory_asset_bundle_ =
         std::make_unique<blink::DirectoryAssetBundle>(path);
-    return;
+    flx_path = files::GetDirectoryName(path) + "/app.flx";
+  } else if (S_ISREG(stat_result.st_mode)) {
+    flx_path = path;
   }
 
-  if (S_ISREG(stat_result.st_mode)) {
+  if (PathExists(flx_path)) {
     asset_store_ = fxl::MakeRefCounted<blink::ZipAssetStore>(
-        blink::GetUnzipperProviderForPath(path));
-    directory_asset_bundle_ = std::make_unique<blink::DirectoryAssetBundle>(
-        files::GetDirectoryName(path));
-    return;
+        blink::GetUnzipperProviderForPath(flx_path));
   }
 }
 
@@ -595,12 +603,9 @@ void Engine::HandleAssetPlatformMessage(
   const auto& data = message->data();
   std::string asset_name(reinterpret_cast<const char*>(data.data()),
                          data.size());
-  std::vector<uint8_t> asset_data;
-  if (GetAssetAsBuffer(asset_name, &asset_data)) {
-    response->Complete(std::move(asset_data));
-  } else {
-    response->CompleteEmpty();
-  }
+  std::string asset_path = directory_asset_bundle_->GetPathForAsset(asset_name);
+  response->Complete(
+      std::vector<uint8_t>(asset_path.begin(), asset_path.end()));
 }
 
 bool Engine::GetAssetAsBuffer(const std::string& name,

shell/common/engine.h

@@ -116,7 +116,7 @@ class Engine : public blink::RuntimeDelegate {
   std::string country_code_;
   std::string user_settings_data_;
   bool semantics_enabled_ = false;
-  // TODO(abarth): Unify these two behind a common interface.
+  // TODO(zarah): Remove usage of asset_store_ once app.flx is removed.
   fxl::RefPtr<blink::ZipAssetStore> asset_store_;
   std::unique_ptr<blink::DirectoryAssetBundle> directory_asset_bundle_;
   // TODO(eseidel): This should move into an AnimatorStateMachine.

shell/common/switches.h

@@ -62,6 +62,9 @@ DEF_SWITCH(EnableTxt,
            "enable-txt",
            "Enable libtxt as the text shaping library instead of Blink.")
 DEF_SWITCH(FLX, "flx", "Specify the FLX path.")
+DEF_SWITCH(FlutterAssetsDir,
+           "flutter-assets-dir",
+           "Path to the Flutter assets directory.")
 DEF_SWITCH(Help, "help", "Display this help text.")
 DEF_SWITCH(LogTag, "log-tag", "Tag associated with log messages.")
 DEF_SWITCH(MainDartFile, "dart-main", "The path to the main Dart file.")

shell/platform/android/io/flutter/view/FlutterMain.java

@@ -38,6 +38,7 @@ public class FlutterMain {
     private static final String AOT_ISOLATE_SNAPSHOT_INSTR_KEY = "isolate-snapshot-instr";
     private static final String FLX_KEY = "flx";
     private static final String SNAPSHOT_BLOB_KEY = "snapshot-blob";
+    private static final String FLUTTER_ASSETS_DIR_KEY = "flutter-assets-dir";
 
     // XML Attribute keys supported in AndroidManifest.xml
     public static final String PUBLIC_AOT_AOT_SHARED_LIBRARY_PATH =
@@ -54,6 +55,8 @@ public class FlutterMain {
         FlutterMain.class.getName() + '.' + FLX_KEY;
     public static final String PUBLIC_SNAPSHOT_BLOB_KEY =
         FlutterMain.class.getName() + '.' + SNAPSHOT_BLOB_KEY;
+    public static final String PUBLIC_FLUTTER_ASSETS_DIR_KEY =
+        FlutterMain.class.getName() + '.' + FLUTTER_ASSETS_DIR_KEY;
 
     // Resource names used for components of the precompiled snapshot.
     private static final String DEFAULT_AOT_SHARED_LIBRARY_PATH= "app.so";
@@ -63,6 +66,7 @@ public class FlutterMain {
     private static final String DEFAULT_AOT_ISOLATE_SNAPSHOT_INSTR = "isolate_snapshot_instr";
     private static final String DEFAULT_FLX = "app.flx";
     private static final String DEFAULT_SNAPSHOT_BLOB = "snapshot_blob.bin";
+    private static final String DEFAULT_FLUTTER_ASSETS_DIR = "flutter_assets";
 
     private static final String MANIFEST = "flutter.yaml";
 
@@ -79,6 +83,7 @@ public class FlutterMain {
     private static String sAotIsolateSnapshotInstr = DEFAULT_AOT_ISOLATE_SNAPSHOT_INSTR;
     private static String sFlx = DEFAULT_FLX;
     private static String sSnapshotBlob = DEFAULT_SNAPSHOT_BLOB;
+    private static String sFlutterAssetsDir = DEFAULT_FLUTTER_ASSETS_DIR;
 
     private static boolean sInitialized = false;
     private static ResourceExtractor sResourceExtractor;
@@ -239,6 +244,7 @@ private static void initResources(Context applicationContext) {
         sResourceExtractor = new ResourceExtractor(context)
             .addResources(SKY_RESOURCES)
             .addResource(sFlx);
+            .addResource(sFlutterAssetsDir)
         if (sIsPrecompiledAsSharedLibrary) {
           sResourceExtractor
             .addResource(sAotSharedLibraryPath);
@@ -290,7 +296,7 @@ public static boolean isRunningPrecompiledCode() {
 
     public static String findAppBundlePath(Context applicationContext) {
         String dataDirectory = PathUtils.getDataDirectory(applicationContext);
-        File appBundle = new File(dataDirectory, sFlx);
+        File appBundle = new File(dataDirectory, sFlutterAssetsDir);
         return appBundle.exists() ? appBundle.getPath() : null;
     }
 }

shell/platform/android/io/flutter/view/ResourceExtractor.java

@@ -17,8 +17,10 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
+import java.util.Arrays;
 import java.util.Collection;
 import java.util.HashSet;
+import java.util.LinkedList;
 import java.util.concurrent.CancellationException;
 import java.util.concurrent.ExecutionException;
 
@@ -48,37 +50,40 @@ private void extractResources() {
             try {
                 byte[] buffer = null;
                 final String[] assets = manager.list("");
-                for (String asset : assets) {
+                LinkedList<String> assetList = new LinkedList<>(Arrays.asList(assets));
+                while(!assetList.isEmpty()) {
+                    String asset = assetList.pop();
                     if (!mResources.contains(asset))
                         continue;
+
+		    if (manager.list(asset).length > 0) {
+			// The asset is a directory
+			for (String a: manager.list(asset)) {
+			    assetList.add(asset + File.separator + a);
+			    mResources.add(asset + File.separator + a);
+			}
+			continue;
+		    }
+
                     final File output = new File(dataDir, asset);
                     if (output.exists())
                         continue;
-                    InputStream is = null;
-                    OutputStream os = null;
-                    try {
-                        is = manager.open(asset);
-                        os = new FileOutputStream(output);
-                        if (buffer == null) {
-                            buffer = new byte[BUFFER_SIZE];
-                        }
-
-                        int count = 0;
-                        while ((count = is.read(buffer, 0, BUFFER_SIZE)) != -1) {
-                            os.write(buffer, 0, count);
-                        }
-                        os.flush();
-                    } finally {
-                        try {
-                            if (is != null) {
-                                is.close();
-                            }
-                        } finally {
-                            if (os != null) {
-                                os.close();
-                            }
-                        }
+                    if (output.getParentFile() != null) {
+                        output.getParentFile().mkdirs();
                     }
+                    try (InputStream is = manager.open(asset)) {
+                        try (OutputStream os = new FileOutputStream(output)) {
+                            if (buffer == null) {
+                                buffer = new byte[BUFFER_SIZE];
+                             }
+
+                            int count = 0;
+                            while ((count = is.read(buffer, 0, BUFFER_SIZE)) != -1) {
+                                os.write(buffer, 0, count);
+                            }
+                            os.flush();
+			}
+		    }
                 }
             } catch (IOException e) {
                 Log.w(TAG, "Exception unpacking resources: " + e.getMessage());
@@ -179,10 +184,18 @@ public boolean accept(File dir, String name) {
 
     private void deleteFiles() {
         final File dataDir = new File(PathUtils.getDataDirectory(mContext));
-        for (String resource : mResources) {
+        LinkedList<String> files = new LinkedList<>(mResources);
+        while (!files.isEmpty()) {
+            String resource = files.pop();
             final File file = new File(dataDir, resource);
             if (file.exists()) {
-                file.delete();
+                if (file.isFile()) {
+                    file.delete();
+                } else {
+		    for (String f : file.list()) {
+			files.add(resource + File.separator + f);
+		    }
+                }
             }
         }
         for (String timestamp : getExistingTimestamps(dataDir)) {

shell/platform/darwin/ios/framework/Headers/FlutterDartProject.h

@@ -20,6 +20,13 @@ FLUTTER_EXPORT
 
 - (instancetype)initWithFLXArchiveWithScriptSnapshot:(NSURL*)archiveURL NS_DESIGNATED_INITIALIZER;
 
+- (instancetype)initWithFlutterAssets:(NSURL*)archiveURL
+                             dartMain:(NSURL*)dartMainURL
+                             packages:(NSURL*)dartPackages NS_DESIGNATED_INITIALIZER;
+
+- (instancetype)initWithFlutterAssetsWithScriptSnapshot:(NSURL*)archiveURL
+    NS_DESIGNATED_INITIALIZER;
+
 - (instancetype)initFromDefaultSourceForConfiguration;
 
 @end