Hide ProtocolHandler implementation

Move ProtocolHandler implementation and fields into DBusProtocolHandler
and extract a ProtocolHandler interface.

Bug: 25932908
Test: `mmma -j16 system/webservd`

Change-Id: I9100387f331e899da9bf44202ce2becf5fad4895
diff --git a/libwebserv/protocol_handler.cc b/libwebserv/protocol_handler.cc
index 8c50d47..b4e54b4 100644
--- a/libwebserv/protocol_handler.cc
+++ b/libwebserv/protocol_handler.cc
@@ -12,303 +12,11 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#include "libwebserv/protocol_handler.h"
-
-#include <tuple>
-
-#include <base/logging.h>
-#include <brillo/map_utils.h>
-#include <brillo/streams/file_stream.h>
-#include <brillo/streams/stream_utils.h>
-
-#include "dbus_bindings/org.chromium.WebServer.RequestHandler.h"
-#include "libwebserv/dbus_server.h"
-#include "libwebserv/request.h"
-#include "libwebserv/request_handler_callback.h"
-#include "libwebserv/response_impl.h"
-#include "webservd/dbus-proxies.h"
+#include <libwebserv/protocol_handler.h>
 
 namespace libwebserv {
 
-namespace {
-
-// Dummy callback for async D-Bus errors.
-void IgnoreDBusError(brillo::Error* error) {}
-
-// Copies the data from |src_stream| to the destination stream represented
-// by a file descriptor |fd|.
-void WriteResponseData(brillo::StreamPtr src_stream,
-                       const dbus::FileDescriptor& fd) {
-  int dupfd = dup(fd.value());
-  auto dest_stream =
-      brillo::FileStream::FromFileDescriptor(dupfd, true, nullptr);
-  CHECK(dest_stream);
-  // Dummy callbacks for success/error of data-copy operation. We ignore both
-  // notifications here.
-  auto on_success = [](brillo::StreamPtr, brillo::StreamPtr, uint64_t) {};
-  auto on_error = [](brillo::StreamPtr, brillo::StreamPtr,
-                     const brillo::Error*) {};
-  brillo::stream_utils::CopyData(
-      std::move(src_stream), std::move(dest_stream), base::Bind(on_success),
-      base::Bind(on_error));
-}
-
-}  // anonymous namespace
-
-const char ProtocolHandler::kHttp[] = "http";
+const char ProtocolHandler::kHttp[] =  "http";
 const char ProtocolHandler::kHttps[] = "https";
 
-ProtocolHandler::ProtocolHandler(const std::string& name, DBusServer* server)
-    : name_{name}, server_{server} {
-}
-
-ProtocolHandler::~ProtocolHandler() {
-  // Remove any existing handlers, so the web server knows that we don't
-  // need them anymore.
-
-  // We need to get a copy of the map keys since removing the handlers will
-  // modify the map in the middle of the loop and that's not a good thing.
-  auto handler_ids = brillo::GetMapKeys(request_handlers_);
-  for (int handler_id : handler_ids) {
-    RemoveHandler(handler_id);
-  }
-}
-
-std::string ProtocolHandler::GetName() const {
-  return name_;
-}
-
-std::set<uint16_t> ProtocolHandler::GetPorts() const {
-  std::set<uint16_t> ports;
-  for (const auto& pair : proxies_)
-    ports.insert(pair.second->port());
-  return ports;
-}
-
-std::set<std::string> ProtocolHandler::GetProtocols() const {
-  std::set<std::string> protocols;
-  for (const auto& pair : proxies_)
-    protocols.insert(pair.second->protocol());
-  return protocols;
-}
-
-brillo::Blob ProtocolHandler::GetCertificateFingerprint() const {
-  brillo::Blob fingerprint;
-  for (const auto& pair : proxies_) {
-    fingerprint = pair.second->certificate_fingerprint();
-    if (!fingerprint.empty())
-      break;
-  }
-  return fingerprint;
-}
-
-int ProtocolHandler::AddHandler(
-    const std::string& url,
-    const std::string& method,
-    std::unique_ptr<RequestHandlerInterface> handler) {
-  request_handlers_.emplace(
-      ++last_handler_id_,
-      HandlerMapEntry{url, method,
-                      std::map<ProtocolHandlerProxyInterface*, std::string>{},
-                      std::move(handler)});
-  // For each instance of remote protocol handler object sharing the same name,
-  // add the request handler.
-  for (const auto& pair : proxies_) {
-    pair.second->AddRequestHandlerAsync(
-        url,
-        method,
-        server_->service_name_,
-        base::Bind(&ProtocolHandler::AddHandlerSuccess,
-                   weak_ptr_factory_.GetWeakPtr(),
-                   last_handler_id_,
-                   pair.second),
-        base::Bind(&ProtocolHandler::AddHandlerError,
-                   weak_ptr_factory_.GetWeakPtr(),
-                   last_handler_id_));
-  }
-  return last_handler_id_;
-}
-
-int ProtocolHandler::AddHandlerCallback(
-    const std::string& url,
-    const std::string& method,
-    const base::Callback<RequestHandlerInterface::HandlerSignature>&
-        handler_callback) {
-  std::unique_ptr<RequestHandlerInterface> handler{
-      new RequestHandlerCallback{handler_callback}};
-  return AddHandler(url, method, std::move(handler));
-}
-
-bool ProtocolHandler::RemoveHandler(int handler_id) {
-  auto p = request_handlers_.find(handler_id);
-  if (p == request_handlers_.end())
-    return false;
-
-  for (const auto& pair : p->second.remote_handler_ids) {
-    pair.first->RemoveRequestHandlerAsync(
-        pair.second,
-        base::Bind(&base::DoNothing),
-        base::Bind(&IgnoreDBusError));
-  }
-
-  request_handlers_.erase(p);
-  return true;
-}
-
-void ProtocolHandler::Connect(ProtocolHandlerProxyInterface* proxy) {
-  proxies_.emplace(proxy->GetObjectPath(), proxy);
-  for (const auto& pair : request_handlers_) {
-    proxy->AddRequestHandlerAsync(
-        pair.second.url,
-        pair.second.method,
-        server_->service_name_,
-        base::Bind(&ProtocolHandler::AddHandlerSuccess,
-                   weak_ptr_factory_.GetWeakPtr(),
-                   pair.first,
-                   proxy),
-        base::Bind(&ProtocolHandler::AddHandlerError,
-                   weak_ptr_factory_.GetWeakPtr(),
-                   pair.first));
-  }
-}
-
-void ProtocolHandler::Disconnect(const dbus::ObjectPath& object_path) {
-  proxies_.erase(object_path);
-  if (proxies_.empty())
-    remote_handler_id_map_.clear();
-  for (auto& pair : request_handlers_)
-    pair.second.remote_handler_ids.clear();
-}
-
-void ProtocolHandler::AddHandlerSuccess(int handler_id,
-                                        ProtocolHandlerProxyInterface* proxy,
-                                        const std::string& remote_handler_id) {
-  auto p = request_handlers_.find(handler_id);
-  CHECK(p != request_handlers_.end());
-  p->second.remote_handler_ids.emplace(proxy, remote_handler_id);
-
-  remote_handler_id_map_.emplace(remote_handler_id, handler_id);
-}
-
-void ProtocolHandler::AddHandlerError(int handler_id, brillo::Error* error) {
-  // Nothing to do at the moment.
-}
-
-bool ProtocolHandler::ProcessRequest(const std::string& protocol_handler_id,
-                                     const std::string& remote_handler_id,
-                                     const std::string& request_id,
-                                     std::unique_ptr<Request> request,
-                                     brillo::ErrorPtr* error) {
-  request_id_map_.emplace(request_id, protocol_handler_id);
-  auto id_iter = remote_handler_id_map_.find(remote_handler_id);
-  if (id_iter == remote_handler_id_map_.end()) {
-    brillo::Error::AddToPrintf(error, FROM_HERE,
-                               brillo::errors::dbus::kDomain,
-                               DBUS_ERROR_FAILED,
-                               "Unknown request handler '%s'",
-                               remote_handler_id.c_str());
-    return false;
-  }
-  auto handler_iter = request_handlers_.find(id_iter->second);
-  if (handler_iter == request_handlers_.end()) {
-    brillo::Error::AddToPrintf(error, FROM_HERE,
-                               brillo::errors::dbus::kDomain,
-                               DBUS_ERROR_FAILED,
-                               "Handler # %d is no longer available",
-                               id_iter->second);
-    return false;
-  }
-  handler_iter->second.handler->HandleRequest(
-      std::move(request),
-      std::unique_ptr<Response>{new ResponseImpl{this, request_id}});
-  return true;
-}
-
-void ProtocolHandler::CompleteRequest(
-    const std::string& request_id,
-    int status_code,
-    const std::multimap<std::string, std::string>& headers,
-    brillo::StreamPtr data_stream) {
-  ProtocolHandlerProxyInterface* proxy =
-      GetRequestProtocolHandlerProxy(request_id);
-  if (!proxy)
-    return;
-
-  std::vector<std::tuple<std::string, std::string>> header_list;
-  header_list.reserve(headers.size());
-  for (const auto& pair : headers)
-    header_list.emplace_back(pair.first, pair.second);
-
-  int64_t data_size = -1;
-  if (data_stream->CanGetSize())
-    data_size = data_stream->GetRemainingSize();
-  proxy->CompleteRequestAsync(
-      request_id, status_code, header_list, data_size,
-      base::Bind(&WriteResponseData, base::Passed(&data_stream)),
-      base::Bind(&IgnoreDBusError));
-}
-
-void ProtocolHandler::GetFileData(
-    const std::string& request_id,
-    int file_id,
-    const base::Callback<void(brillo::StreamPtr)>& success_callback,
-    const base::Callback<void(brillo::Error*)>& error_callback) {
-  ProtocolHandlerProxyInterface* proxy =
-      GetRequestProtocolHandlerProxy(request_id);
-  CHECK(proxy);
-
-  // Store the success/error callback in a shared object so it can be referenced
-  // by the two wrapper callbacks. Since the original callbacks MAY contain
-  // move-only types, copying the base::Callback object is generally unsafe and
-  // may destroy the source object of the copy (despite the fact that it is
-  // constant). So, here we move both callbacks to |Callbacks| structure and
-  // use a shared pointer to it in both success and error callback wrappers.
-  struct Callbacks {
-    base::Callback<void(brillo::StreamPtr)> on_success;
-    base::Callback<void(brillo::Error*)> on_error;
-  };
-  auto callbacks = std::make_shared<Callbacks>();
-  callbacks->on_success = success_callback;
-  callbacks->on_error = error_callback;
-
-  auto on_success = [callbacks](const dbus::FileDescriptor& fd) {
-    brillo::ErrorPtr error;
-    // Unfortunately there is no way to take ownership of the file descriptor
-    // since |fd| is a const reference, so duplicate the descriptor.
-    int dupfd = dup(fd.value());
-    auto stream = brillo::FileStream::FromFileDescriptor(dupfd, true, &error);
-    if (!stream)
-      return callbacks->on_error.Run(error.get());
-    callbacks->on_success.Run(std::move(stream));
-  };
-  auto on_error = [callbacks](brillo::Error* error) {
-    callbacks->on_error.Run(error);
-  };
-
-  proxy->GetRequestFileDataAsync(request_id, file_id, base::Bind(on_success),
-                                 base::Bind(on_error));
-}
-
-ProtocolHandler::ProtocolHandlerProxyInterface*
-ProtocolHandler::GetRequestProtocolHandlerProxy(
-    const std::string& request_id) const {
-  auto iter = request_id_map_.find(request_id);
-  if (iter == request_id_map_.end()) {
-    LOG(ERROR) << "Can't find pending request with ID " << request_id;
-    return nullptr;
-  }
-  std::string handler_id = iter->second;
-  auto find_proxy_by_id = [handler_id](decltype(*proxies_.begin()) pair) {
-    return pair.second->id() == handler_id;
-  };
-  auto proxy_iter = std::find_if(proxies_.begin(), proxies_.end(),
-                                 find_proxy_by_id);
-  if (proxy_iter == proxies_.end()) {
-    LOG(WARNING) << "Completing a request after the handler proxy is removed";
-    return nullptr;
-  }
-  return proxy_iter->second;
-}
-
-
 }  // namespace libwebserv