AAPT2: Add a APK filtering.

Allow resource files to be removed from the final artifact based on the
density and locale configuration in the config file. The APK is split
along the density, locale and ABI axis. Each split is generated from the
original APK without modifying the original. The new resource table is
written back to the file system with unneeded assets etc removed.

Test: Unit tests
Test: Manually run optimize command against an APK and inspect results
Test: Installed split searchlite APK (after resigning) and ran on N6

Change-Id: If73597dcfd88c02d2616518585d0e25a5c6a84d1

1 files changed, 147 insertions, 0 deletions

diff --git a/tools/aapt2/optimize/MultiApkGenerator.cpp b/tools/aapt2/optimize/MultiApkGenerator.cpp
new file mode 100644
index 000000000000..f413ee960264
--- /dev/null
+++ b/tools/aapt2/optimize/MultiApkGenerator.cpp
@@ -0,0 +1,147 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "MultiApkGenerator.h"
+
+#include <algorithm>
+#include <string>
+
+#include "androidfw/StringPiece.h"
+
+#include "LoadedApk.h"
+#include "configuration/ConfigurationParser.h"
+#include "filter/AbiFilter.h"
+#include "filter/Filter.h"
+#include "flatten/Archive.h"
+#include "process/IResourceTableConsumer.h"
+#include "split/TableSplitter.h"
+#include "util/Files.h"
+
+namespace aapt {
+
+using ::aapt::configuration::Artifact;
+using ::aapt::configuration::PostProcessingConfiguration;
+using ::android::StringPiece;
+
+MultiApkGenerator::MultiApkGenerator(LoadedApk* apk, IAaptContext* context)
+    : apk_(apk), context_(context) {
+}
+
+bool MultiApkGenerator::FromBaseApk(const std::string& out_dir,
+                                    const PostProcessingConfiguration& config,
+                                    const TableFlattenerOptions& table_flattener_options) {
+  // TODO(safarmer): Handle APK version codes for the generated APKs.
+  // TODO(safarmer): Handle explicit outputs/generating an output file list for other tools.
+
+  const std::string& apk_path = apk_->GetSource().path;
+  const StringPiece ext = file::GetExtension(apk_path);
+  const std::string base_name = apk_path.substr(0, apk_path.rfind(ext.to_string()));
+
+  // For now, just write out the stripped APK since ABI splitting doesn't modify anything else.
+  for (const Artifact& artifact : config.artifacts) {
+    FilterChain filters;
+    TableSplitterOptions splits;
+    AxisConfigFilter axis_filter;
+
+    if (!artifact.name && !config.artifact_format) {
+      context_->GetDiagnostics()->Error(
+          DiagMessage() << "Artifact does not have a name and no global name template defined");
+      return false;
+    }
+
+    Maybe<std::string> artifact_name =
+        (artifact.name)
+            ? artifact.Name(base_name, ext.substr(1), context_->GetDiagnostics())
+            : artifact.ToArtifactName(config.artifact_format.value(), context_->GetDiagnostics(),
+                                      base_name, ext.substr(1));
+
+    if (!artifact_name) {
+      context_->GetDiagnostics()->Error(DiagMessage()
+                                        << "Could not determine split APK artifact name");
+      return false;
+    }
+
+    if (artifact.abi_group) {
+      const std::string& group_name = artifact.abi_group.value();
+
+      auto group = config.abi_groups.find(group_name);
+      // TODO: Remove validation when configuration parser ensures referential integrity.
+      if (group == config.abi_groups.end()) {
+        context_->GetDiagnostics()->Error(DiagMessage() << "could not find referenced ABI group '"
+                                                        << group_name << "'");
+        return false;
+      }
+      filters.AddFilter(AbiFilter::FromAbiList(group->second));
+    }
+
+    if (artifact.screen_density_group) {
+      const std::string& group_name = artifact.screen_density_group.value();
+
+      auto group = config.screen_density_groups.find(group_name);
+      // TODO: Remove validation when configuration parser ensures referential integrity.
+      if (group == config.screen_density_groups.end()) {
+        context_->GetDiagnostics()->Error(DiagMessage() << "could not find referenced group '"
+                                                        << group_name << "'");
+        return false;
+      }
+
+      const std::vector<ConfigDescription>& densities = group->second;
+      std::for_each(densities.begin(), densities.end(), [&](const ConfigDescription& c) {
+        splits.preferred_densities.push_back(c.density);
+      });
+    }
+
+    if (artifact.locale_group) {
+      const std::string& group_name = artifact.locale_group.value();
+      auto group = config.locale_groups.find(group_name);
+      // TODO: Remove validation when configuration parser ensures referential integrity.
+      if (group == config.locale_groups.end()) {
+        context_->GetDiagnostics()->Error(DiagMessage() << "could not find referenced group '"
+                                                        << group_name << "'");
+        return false;
+      }
+
+      const std::vector<ConfigDescription>& locales = group->second;
+      std::for_each(locales.begin(), locales.end(),
+                    [&](const ConfigDescription& c) { axis_filter.AddConfig(c); });
+      splits.config_filter = &axis_filter;
+    }
+
+    std::unique_ptr<ResourceTable> table = apk_->GetResourceTable()->Clone();
+
+    TableSplitter splitter{{}, splits};
+    splitter.SplitTable(table.get());
+
+    std::string out = out_dir;
+    file::AppendPath(&out, artifact_name.value());
+
+    std::unique_ptr<IArchiveWriter> writer =
+        CreateZipFileArchiveWriter(context_->GetDiagnostics(), out);
+
+    if (context_->IsVerbose()) {
+      context_->GetDiagnostics()->Note(DiagMessage() << "Writing output: " << out);
+    }
+
+    if (!apk_->WriteToArchive(context_, table.get(), table_flattener_options, &filters,
+                              writer.get())) {
+      return false;
+    }
+  }
+
+  return true;
+}
+
+}  // namespace aapt