Add onGetUsbPrinterInfoRequested event to printerProvider API.

extensions/browser/api/printer_provider/printer_provider_api.cc

Index: extensions/browser/api/printer_provider/printer_provider_api.cc
diff --git a/extensions/browser/api/printer_provider/printer_provider_api.cc b/extensions/browser/api/printer_provider/printer_provider_api.cc
index cf1fda6ed4e7fde4a6d74c021b97c39b830ad54b..4d298e5f80b8fea6cde90dded690fc40fa998a13 100644
--- a/extensions/browser/api/printer_provider/printer_provider_api.cc
+++ b/extensions/browser/api/printer_provider/printer_provider_api.cc
@@ -18,6 +18,10 @@
 #include "base/strings/string16.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
+#include "device/core/device_client.h"
+#include "device/usb/usb_device.h"
+#include "device/usb/usb_service.h"
+#include "extensions/browser/api/device_permissions_manager.h"
 #include "extensions/browser/api/printer_provider/printer_provider_print_job.h"
 #include "extensions/browser/api/printer_provider_internal/printer_provider_internal_api.h"
 #include "extensions/browser/api/printer_provider_internal/printer_provider_internal_api_observer.h"
@@ -25,8 +29,16 @@
 #include "extensions/browser/extension_registry.h"
 #include "extensions/browser/extension_registry_observer.h"
 #include "extensions/common/api/printer_provider.h"
+#include "extensions/common/api/printer_provider/usb_printer_manifest_data.h"
 #include "extensions/common/api/printer_provider_internal.h"
+#include "extensions/common/api/usb.h"
 #include "extensions/common/extension.h"
+#include "extensions/common/permissions/permissions_data.h"
+#include "extensions/common/value_builder.h"
+
+using device::UsbDevice;
+using device::UsbDeviceFilter;
+using device::UsbService;
 
 namespace extensions {
 
@@ -68,12 +80,13 @@ bool ParsePrinterId(const std::string& printer_id,
 class GetPrintersRequest {
  public:
   explicit GetPrintersRequest(
+      bool wait_for_usb_printers,
       const PrinterProviderAPI::GetPrintersCallback& callback);
   ~GetPrintersRequest();
 
   // Adds an extension id to the list of the extensions that need to respond
   // to the event.
-  void AddSource(const std::string& extension_id);
+  void AddSource(const std::string& extension);
 
   // Whether all extensions have responded to the event.
   bool IsDone() const;
@@ -83,6 +96,10 @@ class GetPrintersRequest {
   void ReportForExtension(const std::string& extension_id,
                           const base::ListValue& printers);
 
+  // Runs the callback for USB printers and clears the request for a list of
+  // USB printers.
+  void ReportUsbPrinters(const base::ListValue& printers);
+
  private:
   // Callback reporting event result for an extension. Called once for each
   // extension.
@@ -90,6 +107,10 @@ class GetPrintersRequest {
 
   // The list of extensions that still have to respond to the event.
   std::set<std::string> extensions_;
+
+  // Set when an extension supporting USB printers is detected and the
+  // GetPrintersRequest is not done until those devices are reported.
+  bool wait_for_usb_printers_;
 };
 
 // Keeps track of pending chrome.printerProvider.onGetPrintersRequested
@@ -101,7 +122,8 @@ class PendingGetPrintersRequests {
 
   // Adds a new request to the set of pending requests. Returns the id
   // assigned to the request.
-  int Add(const PrinterProviderAPI::GetPrintersCallback& callback);
+  int Add(bool wait_for_usb_printers,
+          const PrinterProviderAPI::GetPrintersCallback& callback);
 
   // Completes a request for an extension. It runs the request callback with
   // values reported by the extension.
@@ -114,8 +136,12 @@ class PendingGetPrintersRequests {
   // called as if the extension reported empty set of printers.
   void FailAllForExtension(const std::string& extension_id);
 
-  // Adds an extension id to the list of the extensions that need to respond
-  // to the event.
+  // Completes a request for all USB printers associated with registered
+  // extensions.
+  void CompleteUsbPrinters(int request_id, const base::ListValue& result);
+
+  // Adds an extension to the list of the extensions that need to respond to the
+  // event.
   bool AddSource(int request_id, const std::string& extension_id);
 
  private:
@@ -149,7 +175,7 @@ class PendingGetCapabilityRequests {
   std::map<int, PrinterProviderAPI::GetCapabilityCallback> pending_requests_;
 };
 
-// Keeps track of pending chrome.printerProvider.ontPrintRequested requests
+// Keeps track of pending chrome.printerProvider.onPrintRequested requests
 // for an extension.
 class PendingPrintRequests {
  public:
@@ -182,6 +208,31 @@ class PendingPrintRequests {
   std::map<int, PrintRequest> pending_requests_;
 };
 
+// Keeps track of pending chrome.printerProvider.onUsbAccessGranted requests
+// for an extension.
+class PendingUsbPrinterInfoRequests {
+ public:
+  PendingUsbPrinterInfoRequests();
+  ~PendingUsbPrinterInfoRequests();
+
+  // Adds a new request to the set. Only information needed is the callback
+  // associated with the request. Returns the id assigned to the request.
+  int Add(const PrinterProviderAPI::UsbAccessGrantedCallback& callback);
+
+  // Completes the request with the provided request id. It runs the request
+  // callback and removes the request from the set.
+  void Complete(int request_id,
+                const core_api::printer_provider::PrinterInfo* printer_info);
+
+  // Runs all pending callbacks with empty capability value and clears the
+  // set of pending requests.
+  void FailAll();
+
+ private:
+  int last_request_id_ = 0;
+  std::map<int, PrinterProviderAPI::UsbAccessGrantedCallback> pending_requests_;
+};
+
 // Implements chrome.printerProvider API events.
 class PrinterProviderAPIImpl : public PrinterProviderAPI,
                                public PrinterProviderInternalAPIObserver,
@@ -202,6 +253,10 @@ class PrinterProviderAPIImpl : public PrinterProviderAPI,
       const PrinterProviderAPI::PrintCallback& callback) override;
   const PrinterProviderPrintJob* GetPrintJob(const Extension* extension,
                                              int request_id) const override;
+  void DispatchGrantUsbPrinterAccess(
+      const std::string& extension_id,
+      int device_id,
+      const PrinterProviderAPI::UsbAccessGrantedCallback& callback) override;
 
   // PrinterProviderInternalAPIObserver implementation:
   void OnGetPrintersResult(
@@ -216,6 +271,10 @@ class PrinterProviderAPIImpl : public PrinterProviderAPI,
       const Extension* extension,
       int request_id,
       core_api::printer_provider_internal::PrintError error) override;
+  void OnUsbAccessGrantedResult(
+      const Extension* extension,
+      int request_id,
+      const core_api::printer_provider::PrinterInfo* printer_info) override;
 
   // ExtensionRegistryObserver implementation:
   void OnExtensionUnloaded(content::BrowserContext* browser_context,
@@ -232,6 +291,10 @@ class PrinterProviderAPIImpl : public PrinterProviderAPI,
                            const Extension* extension,
                            base::ListValue* args);
 
+  void OnUsbDevicesEnumerated(
+      int request_id,
+      const std::vector<scoped_refptr<UsbDevice>>& devices);
+
   content::BrowserContext* browser_context_;
 
   PendingGetPrintersRequests pending_get_printers_requests_;
@@ -241,18 +304,24 @@ class PrinterProviderAPIImpl : public PrinterProviderAPI,
   std::map<std::string, PendingGetCapabilityRequests>
       pending_capability_requests_;
 
+  std::map<std::string, PendingUsbPrinterInfoRequests>
+      pending_usb_printer_info_requests_;
+
   ScopedObserver<PrinterProviderInternalAPI, PrinterProviderInternalAPIObserver>
       internal_api_observer_;
 
   ScopedObserver<ExtensionRegistry, ExtensionRegistryObserver>
       extension_registry_observer_;
 
+  base::WeakPtrFactory<PrinterProviderAPIImpl> weak_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(PrinterProviderAPIImpl);
 };
 
 GetPrintersRequest::GetPrintersRequest(
+    bool wait_for_usb_printers,
     const PrinterProviderAPI::GetPrintersCallback& callback)
-    : callback_(callback) {
+    : callback_(callback), wait_for_usb_printers_(wait_for_usb_printers) {
 }
 
 GetPrintersRequest::~GetPrintersRequest() {
@@ -263,7 +332,7 @@ void GetPrintersRequest::AddSource(const std::string& extension_id) {
 }
 
 bool GetPrintersRequest::IsDone() const {
-  return extensions_.empty();
+  return extensions_.empty() && !wait_for_usb_printers_;
 }
 
 void GetPrintersRequest::ReportForExtension(const std::string& extension_id,
@@ -272,6 +341,12 @@ void GetPrintersRequest::ReportForExtension(const std::string& extension_id,
     callback_.Run(printers, IsDone());
 }
 
+void GetPrintersRequest::ReportUsbPrinters(const base::ListValue& printers) {
+  DCHECK(wait_for_usb_printers_);
+  wait_for_usb_printers_ = false;
+  callback_.Run(printers, IsDone());
+}
+
 PendingGetPrintersRequests::PendingGetPrintersRequests() : last_request_id_(0) {
 }
 
@@ -279,9 +354,10 @@ PendingGetPrintersRequests::~PendingGetPrintersRequests() {
 }
 
 int PendingGetPrintersRequests::Add(
+    bool wait_for_usb_printers,
     const PrinterProviderAPI::GetPrintersCallback& callback) {
-  pending_requests_.insert(
-      std::make_pair(++last_request_id_, GetPrintersRequest(callback)));
+  pending_requests_.insert(std::make_pair(
+      ++last_request_id_, GetPrintersRequest(wait_for_usb_printers, callback)));
   return last_request_id_;
 }
 
@@ -312,6 +388,20 @@ void PendingGetPrintersRequests::FailAllForExtension(
   }
 }
 
+void PendingGetPrintersRequests::CompleteUsbPrinters(
+    int request_id,
+    const base::ListValue& result) {
+  auto it = pending_requests_.find(request_id);
+  if (it == pending_requests_.end()) {
+    return;
+  }
+
+  it->second.ReportUsbPrinters(result);
+  if (it->second.IsDone()) {
+    pending_requests_.erase(it);
+  }
+}
+
 bool PendingGetPrintersRequests::AddSource(int request_id,
                                            const std::string& extension_id) {
   auto it = pending_requests_.find(request_id);
@@ -401,11 +491,49 @@ void PendingPrintRequests::FailAll() {
   pending_requests_.clear();
 }
 
+PendingUsbPrinterInfoRequests::PendingUsbPrinterInfoRequests() {
+}
+
+PendingUsbPrinterInfoRequests::~PendingUsbPrinterInfoRequests() {
+}
+
+int PendingUsbPrinterInfoRequests::Add(
+    const PrinterProviderAPI::UsbAccessGrantedCallback& callback) {
+  pending_requests_[++last_request_id_] = callback;
+  return last_request_id_;
+}
+
+void PendingUsbPrinterInfoRequests::Complete(
+    int request_id,
+    const core_api::printer_provider::PrinterInfo* printer_info) {
+  auto it = pending_requests_.find(request_id);
+  if (it == pending_requests_.end()) {
+    return;
+  }
+
+  PrinterProviderAPI::UsbAccessGrantedCallback callback = it->second;
+  pending_requests_.erase(it);
+
+  if (printer_info) {
+    callback.Run(*printer_info->ToValue().get());
+  } else {
+    callback.Run(base::DictionaryValue());
+  }
+}
+
+void PendingUsbPrinterInfoRequests::FailAll() {
+  for (auto& request : pending_requests_) {
+    request.second.Run(base::DictionaryValue());
+  }
+  pending_requests_.clear();
+}
+
 PrinterProviderAPIImpl::PrinterProviderAPIImpl(
     content::BrowserContext* browser_context)
     : browser_context_(browser_context),
       internal_api_observer_(this),
-      extension_registry_observer_(this) {
+      extension_registry_observer_(this),
+      weak_factory_(this) {
   internal_api_observer_.Add(
       PrinterProviderInternalAPI::GetFactoryInstance()->Get(browser_context));
   extension_registry_observer_.Add(ExtensionRegistry::Get(browser_context));
@@ -423,10 +551,21 @@ void PrinterProviderAPIImpl::DispatchGetPrintersRequested(
     return;
   }
 
-  // |pending_get_printers_requests_| take ownership of |request| which gets
-  // NULLed out. Save the pointer before passing it to the requests, as it will
-  // be needed later on.
-  int request_id = pending_get_printers_requests_.Add(callback);
+  bool extensions_support_usb_devices = false;
+  ExtensionRegistry* registry = ExtensionRegistry::Get(browser_context_);
+  for (const auto& extension : registry->enabled_extensions()) {
+    if (UsbPrinterManifestData::Get(extension.get()) &&
+        extension->permissions_data() &&
+        extension->permissions_data()->HasAPIPermission(
+            extensions::APIPermission::kPrinterProvider) &&
+        extension->permissions_data()->HasAPIPermission(
+            extensions::APIPermission::kUsb)) {
+      extensions_support_usb_devices = true;
+    }
+  }
+
+  int request_id = pending_get_printers_requests_.Add(
+      extensions_support_usb_devices, callback);
 
   scoped_ptr<base::ListValue> internal_args(new base::ListValue);
   // Request id is not part of the public API, but it will be massaged out in
@@ -443,6 +582,17 @@ void PrinterProviderAPIImpl::DispatchGetPrintersRequested(
                  base::Unretained(this), request_id);
 
   event_router->BroadcastEvent(event.Pass());
+
+  // Start the USB device enumeration after the event has been broadcast to
+  // extensions as OnUsbDevicesEnumerated may be called synchronously and that
+  // would complete the request before extensions can be Added to it.
+  if (extensions_support_usb_devices) {
+    UsbService* service = device::DeviceClient::Get()->GetUsbService();
+    DCHECK(service);
+    service->GetDevices(
+        base::Bind(&PrinterProviderAPIImpl::OnUsbDevicesEnumerated,
+                   weak_factory_.GetWeakPtr(), request_id));
+  }
 }
 
 void PrinterProviderAPIImpl::DispatchGetCapabilityRequested(
@@ -534,6 +684,49 @@ const PrinterProviderPrintJob* PrinterProviderAPIImpl::GetPrintJob(
   return it->second.GetPrintJob(request_id);
 }
 
+void PrinterProviderAPIImpl::DispatchGrantUsbPrinterAccess(
+    const std::string& extension_id,
+    int device_id,
+    const PrinterProviderAPI::UsbAccessGrantedCallback& callback) {
+  UsbService* service = device::DeviceClient::Get()->GetUsbService();
+  DCHECK(service);
+  scoped_refptr<UsbDevice> device = service->GetDeviceById(device_id);
+  if (!device) {
+    callback.Run(base::DictionaryValue());
+    return;
+  }
+
+  DevicePermissionsManager* permissions_manager =
+      DevicePermissionsManager::Get(browser_context_);
+  DCHECK(permissions_manager);
+  permissions_manager->AllowUsbDevice(extension_id, device);
+
+  EventRouter* event_router = EventRouter::Get(browser_context_);
+  if (!event_router->ExtensionHasEventListener(
+          extension_id,
+          core_api::printer_provider::OnUsbAccessGranted::kEventName)) {
+    callback.Run(base::DictionaryValue());
+    return;
+  }
+
+  int request_id =
+      pending_usb_printer_info_requests_[extension_id].Add(callback);
+  core_api::usb::Device usb_device;
+  usb_device.device = device->unique_id();
+  usb_device.vendor_id = device->vendor_id();
+  usb_device.product_id = device->product_id();
+
+  scoped_ptr<base::ListValue> internal_args(new base::ListValue);
+  // Request id is not part of the public API and it will be massaged out in
+  // custom bindings.
+  internal_args->AppendInteger(request_id);
+  internal_args->Append(usb_device.ToValue().release());
+  scoped_ptr<Event> event(
+      new Event(core_api::printer_provider::OnUsbAccessGranted::kEventName,
+                internal_args.Pass()));
+  event_router->DispatchEventToExtension(extension_id, event.Pass());
+}
+
 void PrinterProviderAPIImpl::OnGetPrintersResult(
     const Extension* extension,
     int request_id,
@@ -590,6 +783,14 @@ void PrinterProviderAPIImpl::OnPrintResult(
       error_str);
 }
 
+void PrinterProviderAPIImpl::OnUsbAccessGrantedResult(
+    const Extension* extension,
+    int request_id,
+    const core_api::printer_provider::PrinterInfo* printer_info) {
+  pending_usb_printer_info_requests_[extension->id()].Complete(request_id,
+                                                               printer_info);
+}
+
 void PrinterProviderAPIImpl::OnExtensionUnloaded(
     content::BrowserContext* browser_context,
     const Extension* extension,
@@ -607,6 +808,12 @@ void PrinterProviderAPIImpl::OnExtensionUnloaded(
     capability_it->second.FailAll();
     pending_capability_requests_.erase(capability_it);
   }
+
+  auto usb_it = pending_usb_printer_info_requests_.find(extension->id());
+  if (usb_it != pending_usb_printer_info_requests_.end()) {
+    usb_it->second.FailAll();
+    pending_usb_printer_info_requests_.erase(usb_it);
+  }
 }
 
 bool PrinterProviderAPIImpl::WillRequestPrinters(
@@ -626,6 +833,56 @@ bool PrinterProviderAPIImpl::WillRequestPrinters(
   return pending_get_printers_requests_.AddSource(request_id, extension->id());
 }
 
+void PrinterProviderAPIImpl::OnUsbDevicesEnumerated(
+    int request_id,
+    const std::vector<scoped_refptr<UsbDevice>>& devices) {
+  std::map<scoped_refptr<UsbDevice>,
+           std::vector<scoped_refptr<const Extension>>> result_map;
+
+  ExtensionRegistry* registry = ExtensionRegistry::Get(browser_context_);
+  for (const auto& extension : registry->enabled_extensions()) {
+    const UsbPrinterManifestData* manifest_data =
+        UsbPrinterManifestData::Get(extension.get());
+
+    if (!manifest_data || !extension->permissions_data() ||
+        !extension->permissions_data()->HasAPIPermission(
+            extensions::APIPermission::kPrinterProvider) ||
+        !extension->permissions_data()->HasAPIPermission(
+            extensions::APIPermission::kUsb)) {
+      continue;
+    }
+
+    for (const auto& device : devices) {
+      if (manifest_data->SupportsDevice(device)) {
+        result_map[device].push_back(extension);
+      }
+    }
+  }
+
+  ListBuilder printer_list;
+  for (const auto& map_entry : result_map) {
+    ListBuilder extension_list;
+    for (const scoped_refptr<const Extension>& extension : map_entry.second) {
+      extension_list.Append(DictionaryBuilder()
+                                .Set("extensionId", extension->id())
+                                .Set("extensionName", extension->name()));
+    }
+
+    const scoped_refptr<UsbDevice>& device = map_entry.first;
+    printer_list.Append(
+        DictionaryBuilder()
+            .Set("name", DevicePermissionsManager::GetPermissionMessage(
+                             device->vendor_id(), device->product_id(),
+                             device->manufacturer_string(),
+                             device->product_string(), base::string16(), false))
+            .Set("usbDevice", static_cast<int>(device->unique_id()))
+            .Set("extensions", extension_list.Pass()));
+  }
+
+  pending_get_printers_requests_.CompleteUsbPrinters(
+      request_id, *printer_list.Build().get());
+}
+
 }  // namespace
 
 // static