Add Promises for EME (Chromium side)

media/base/media_keys.h

 // Copyright 2013 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.
 
 #ifndef MEDIA_BASE_MEDIA_KEYS_H_
 #define MEDIA_BASE_MEDIA_KEYS_H_
 
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 #include "media/base/media_export.h"
 #include "url/gurl.h"
 
 namespace media {
 
 class Decryptor;
 
+template <typename T>
+class CdmPromiseTemplate;
+
+typedef CdmPromiseTemplate<std::string> NewSessionCdmPromise;
+typedef CdmPromiseTemplate<void> SimpleCdmPromise;
+
 // Performs media key operations.
 //
 // All key operations are called on the renderer thread. Therefore, these calls
 // should be fast and nonblocking; key events should be fired asynchronously.
 class MEDIA_EXPORT MediaKeys {
  public:
   // Reported to UMA, so never reuse a value!
   // Must be kept in sync with blink::WebMediaPlayerClient::MediaKeyErrorCode
   // (enforced in webmediaplayer_impl.cc).
+  // TODO(jrummell): Can this be moved to proxy_decryptor as it should only be
+  // used by the prefixed EME code?
   enum KeyError {
     kUnknownError = 1,
     kClientError,
     // The commented v0.1b values below have never been used.
     // kServiceError,
     kOutputError = 4,
     // kHardwareChangeError,
     // kDomainError,
     kMaxKeyError  // Must be last and greater than any legit value.
   };
 
+  // Must be a superset of cdm::MediaKeyException.
+  enum Exception {
+    NOT_SUPPORTED_ERROR,
+    INVALID_STATE_ERROR,
+    INVALID_ACCESS_ERROR,
+    QUOTA_EXCEEDED_ERROR,
+    UNKNOWN_ERROR,
+    CLIENT_ERROR,
+    OUTPUT_ERROR
+  };
+
+  // Type of license required when creating/loading a session.
+  // Must be consistent with the values specified in the spec:
+  // https://dvcs.w3.org/hg/html-media/raw-file/default/encrypted-media/encrypted-media.html#extensions
+  enum SessionType {
+    TEMPORARY_SESSION,
+    PERSISTENT_SESSION
+  };
+
   const static uint32 kInvalidSessionId = 0;
 
   MediaKeys();
   virtual ~MediaKeys();
 
-  // Creates a session with the |content_type| and |init_data| provided.
-  // Returns true if a session is successfully created, false otherwise.
+  // Creates a session with the |init_data_type|, |init_data| and |session_type|
+  // provided.
   // Note: UpdateSession() and ReleaseSession() should only be called after
-  // SessionCreatedCB is fired.
-  // TODO(jrummell): Remove return value when prefixed API is removed.
-  // See http://crbug.com/342510
-  virtual bool CreateSession(uint32 session_id,
-                             const std::string& content_type,
+  // |promise| is resolved.
+  virtual void CreateSession(const std::string& init_data_type,
                              const uint8* init_data,
-                             int init_data_length) = 0;
+                             int init_data_length,
+                             SessionType session_type,
+                             scoped_ptr<NewSessionCdmPromise> promise) = 0;
 
   // Loads a session with the |web_session_id| provided.
   // Note: UpdateSession() and ReleaseSession() should only be called after
-  // SessionCreatedCB is fired.
-  virtual void LoadSession(uint32 session_id,
-                           const std::string& web_session_id) = 0;
+  // |promise| is resolved.
+  virtual void LoadSession(const std::string& web_session_id,
+                           scoped_ptr<NewSessionCdmPromise> promise) = 0;
 
-  // Updates a session specified by |session_id| with |response|.
-  virtual void UpdateSession(uint32 session_id,
+  // Updates a session specified by |web_session_id| with |response|.
+  virtual void UpdateSession(const std::string& web_session_id,
                              const uint8* response,
-                             int response_length) = 0;
+                             int response_length,
+                             scoped_ptr<SimpleCdmPromise> promise) = 0;
 
-  // Releases the session specified by |session_id|.
-  virtual void ReleaseSession(uint32 session_id) = 0;
+  // Releases the session specified by |web_session_id|.
+  virtual void ReleaseSession(const std::string& web_session_id,
+                              scoped_ptr<SimpleCdmPromise> promise) = 0;
 
   // Gets the Decryptor object associated with the MediaKeys. Returns NULL if
   // no Decryptor object is associated. The returned object is only guaranteed
   // to be valid during the MediaKeys' lifetime.
   virtual Decryptor* GetDecryptor();
 
  private:
   DISALLOW_COPY_AND_ASSIGN(MediaKeys);
 };
 
 // Key event callbacks. See the spec for details:
 // https://dvcs.w3.org/hg/html-media/raw-file/default/encrypted-media/encrypted-media.html#event-summary
-typedef base::Callback<
-    void(uint32 session_id, const std::string& web_session_id)>
-    SessionCreatedCB;
-
-typedef base::Callback<void(uint32 session_id,
+typedef base::Callback<void(const std::string& web_session_id,
                             const std::vector<uint8>& message,
                             const GURL& destination_url)> SessionMessageCB;
 
-typedef base::Callback<void(uint32 session_id)> SessionReadyCB;
+typedef base::Callback<void(const std::string& web_session_id)> SessionReadyCB;
 
-typedef base::Callback<void(uint32 session_id)> SessionClosedCB;
+typedef base::Callback<void(const std::string& web_session_id)> SessionClosedCB;
 
-typedef base::Callback<void(uint32 session_id,
-                            media::MediaKeys::KeyError error_code,
-                            uint32 system_code)> SessionErrorCB;
+typedef base::Callback<void(const std::string& web_session_id,
+                            MediaKeys::Exception exception_code,
+                            uint32 system_code,
+                            const std::string& error_message)> SessionErrorCB;
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_MEDIA_KEYS_H_