Introduce Sky packaged apps.

services/sky_packaged_app_viewer/content_handler_impl.cc

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "services/sky_packaged_app_viewer/content_handler_impl.h"
+
+#include <sstream>
+
+#include "base/bind.h"
+#include "base/files/scoped_temp_dir.h"
+#include "base/memory/scoped_vector.h"
+#include "mojo/common/data_pipe_utils.h"
+#include "mojo/public/cpp/application/connect.h"
+#include "mojo/public/cpp/bindings/strong_binding.h"
+#include "mojo/public/cpp/utility/run_loop.h"
+#include "mojo/services/http_server/public/cpp/http_server_util.h"
+#include "mojo/services/http_server/public/interfaces/http_server.mojom.h"
+#include "mojo/services/http_server/public/interfaces/http_server_factory.mojom.h"
+#include "sky/viewer/sky_loader.h"
+#include "third_party/zlib/google/zip_reader.h"
+
+namespace sky_packaged_app_viewer {
+
+class PendingRequest {
+ public:
+  PendingRequest(mojo::InterfaceRequest<mojo::ServiceProvider> services,
+                 mojo::ServiceProviderPtr exposed_services)
+      : services(services.Pass()), exposed_services(exposed_services.Pass()) {}
+
+  mojo::InterfaceRequest<mojo::ServiceProvider> services;
+  mojo::ServiceProviderPtr exposed_services;
+};
+
+class HttpHandler : public http_server::HttpHandler {
+ public:
+  HttpHandler(const base::Callback<void(uint16_t)>& handler_ready_callback,
+              base::FilePath package_root,
+              http_server::HttpServerFactoryPtr http_server_factory)
+      : binding_(this),
+        handler_ready_callback_(handler_ready_callback),
+        package_root_(package_root) {
+    http_server::HttpHandlerPtr http_handler_ptr;
+    binding_.Bind(GetProxy(&http_handler_ptr));
+
+    http_server_factory->CreateHttpServer(GetProxy(&http_server_).Pass(),
+                                          nullptr);
+    http_server_->SetHandler(
+        "/.*", http_handler_ptr.Pass(),
+        base::Bind(&HttpHandler::AddHandlerCallback, base::Unretained(this)));
+  }
+
+  ~HttpHandler() override {}
+
+  // http_server::HttpHandler:
+  void HandleRequest(http_server::HttpRequestPtr request,
+                     const mojo::Callback<void(http_server::HttpResponsePtr)>&
+                         callback) override {
+    std::string relative_path = request->relative_url.get().substr(1);
+
+    // TODO(blundell): Add logic into creating sky_packaged_applications to
+    // make it unnecessary to strip off the "packages/" prefix, namely,
+    // putting all the dependent packages under "packages/".
+    std::string packages_prefix = "packages/";
+    if (!relative_path.compare(0, packages_prefix.size(), packages_prefix))
+      relative_path.erase(0, packages_prefix.size());
+
+    base::FilePath entry_path = package_root_.Append(relative_path);
+    std::string contents;
+    if (!base::ReadFileToString(entry_path, &contents)) {
+      NOTREACHED();
+      return;
+    }
+
+    callback.Run(http_server::CreateHttpResponse(200, contents));
+  }
+
+  void AddHandlerCallback(bool result) {
+    CHECK(result);
+    http_server_->GetPort(
+        base::Bind(&HttpHandler::GetPortCallback, base::Unretained(this)));
+  }
+
+  void GetPortCallback(uint16_t port) { handler_ready_callback_.Run(port); }
+
+  mojo::Binding<http_server::HttpHandler> binding_;
+  base::Callback<void(uint16_t)> handler_ready_callback_;
+  base::FilePath package_root_;
+  http_server::HttpServerPtr http_server_;
+
+  DISALLOW_COPY_AND_ASSIGN(HttpHandler);
+};
+
+class SkyPackagedApplication : public mojo::Application {
+ public:
+  SkyPackagedApplication(mojo::InterfaceRequest<mojo::Application> application,
+                         mojo::URLResponsePtr response)
+      : binding_(this, application.Pass()),
+        initial_response_(response.Pass()) {}
+
+  void Initialize(mojo::ShellPtr shell,
+                  mojo::Array<mojo::String> args,
+                  const mojo::String& url) override {
+    shell_ = shell.Pass();
+    sky_loader_.reset(new sky::SkyLoader(shell_.get(), mojo::URLResponsePtr()));
+  }
+
+  void AcceptConnection(const mojo::String& requestor_url,
+                        mojo::InterfaceRequest<mojo::ServiceProvider> services,
+                        mojo::ServiceProviderPtr exposed_services,
+                        const mojo::String& url) override {
+    if (local_entrypoint_url_ != "") {
+      DCHECK(!initial_response_);
+      sky_loader_->LoadApplication(
+          services.Pass(), exposed_services.Pass(), local_entrypoint_url_);
+      return;
+    }
+
+    PendingRequest* request =
+        new PendingRequest(services.Pass(), exposed_services.Pass());
+    pending_requests_.push_back(request);
+
+    if (initial_response_)
+      ExtractAndSetUpSkyApplication(initial_response_.Pass());
+  }
+
+  void RequestQuit() override { mojo::RunLoop::current()->Quit(); }
+
+ private:
+  void OnHandlerReady(uint16_t port) {
+    std::stringstream ss;

[qsr, 2015/04/16 16:27:33]

Are we using stringstream anywhere in chromium? Usually, we use
base::StringPrintf

[blundell, 2015/04/16 18:07:56]

Done.

+    ss << "http://localhost:" << port << "/main.sky";
+    local_entrypoint_url_ = ss.str();
+    for (PendingRequest* pending_request : pending_requests_) {
+      sky_loader_->LoadApplication(pending_request->services.Pass(),
+                                   pending_request->exposed_services.Pass(),
+                                   local_entrypoint_url_);

[qsr, 2015/04/16 16:27:33]

I'm probably missing something, but why do we need to start a local webserver,
can't you pass a file:/// URL here?

[blundell, 2015/04/16 18:07:56]

Doing it this way enables avoiding any changes within Sky itself; see PS2 and
Eric's comments on it.

+    }
+    pending_requests_.clear();
+  }
+
+  void ConnectToSkyApplication(
+      mojo::InterfaceRequest<mojo::ServiceProvider> services,
+      mojo::ServiceProviderPtr exposed_services) {
+    sky_loader_->LoadApplication(
+        services.Pass(), exposed_services.Pass(), local_entrypoint_url_);
+  }
+
+  void ExtractAndSetUpSkyApplication(mojo::URLResponsePtr response) {
+    // Extract the application.
+    CHECK(unpacked_app_directory_.CreateUniqueTempDir());
+    ExtractApplication(response.Pass());
+    base::FilePath package_root = unpacked_app_directory_.path();
+
+    // Start up the http handler that will serve the application.
+    mojo::ServiceProviderPtr service_provider;
+    shell_->ConnectToApplication("mojo:http_server",
+                                 mojo::GetProxy(&service_provider), nullptr);
+    http_server::HttpServerFactoryPtr http_server_factory;
+    mojo::ConnectToService(service_provider.get(), &http_server_factory);
+
+    http_handler_.reset(
+        new HttpHandler(base::Bind(&SkyPackagedApplication::OnHandlerReady,
+                                   base::Unretained(this)),
+                        package_root, http_server_factory.Pass()));
+  }
+
+  // TODO(blundell): The below two functions should be moved into a utility
+  // file somewhere where they can be shared by this file, the Dart content
+  // handler, and the Python content handler.
+  void ExtractApplication(mojo::URLResponsePtr response) {
+    zip::ZipReader reader;
+    const std::string input_data = CopyToString(response->body.Pass());
+    CHECK(reader.OpenFromString(input_data));
+    base::FilePath temp_dir_path = unpacked_app_directory_.path();
+    while (reader.HasMore()) {
+      CHECK(reader.OpenCurrentEntryInZip());
+      CHECK(reader.ExtractCurrentEntryIntoDirectory(temp_dir_path));
+      CHECK(reader.AdvanceToNextEntry());
+    }
+  }
+
+  std::string CopyToString(mojo::ScopedDataPipeConsumerHandle body) {
+    std::string body_str;
+    bool result = mojo::common::BlockingCopyToString(body.Pass(), &body_str);
+    DCHECK(result);
+    return body_str;
+  }
+
+  mojo::StrongBinding<mojo::Application> binding_;
+  scoped_ptr<HttpHandler> http_handler_;
+  mojo::ShellPtr shell_;
+  mojo::URLResponsePtr initial_response_;
+  ScopedVector<PendingRequest> pending_requests_;
+  base::ScopedTempDir unpacked_app_directory_;
+  scoped_ptr<sky::SkyLoader> sky_loader_;
+  std::string local_entrypoint_url_;
+};
+
+ContentHandlerImpl::ContentHandlerImpl(
+    mojo::InterfaceRequest<mojo::ContentHandler> request)
+    : binding_(this, request.Pass()) {
+}
+
+ContentHandlerImpl::~ContentHandlerImpl() {
+}
+
+void ContentHandlerImpl::StartApplication(
+    mojo::InterfaceRequest<mojo::Application> application,
+    mojo::URLResponsePtr response) {
+  new SkyPackagedApplication(application.Pass(), response.Pass());
+}
+
+}  // namespace sky_packaged_app_viewer