Support getting and deleting token for Instance ID.

google_apis/gcm/engine/unregistration_request.h

 // Copyright 2014 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 GOOGLE_APIS_GCM_ENGINE_UNREGISTRATION_REQUEST_H_
 #define GOOGLE_APIS_GCM_ENGINE_UNREGISTRATION_REQUEST_H_
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/time/time.h"
 #include "google_apis/gcm/base/gcm_export.h"
 #include "net/base/backoff_entry.h"
 #include "net/url_request/url_fetcher_delegate.h"
 #include "url/gurl.h"
 
 namespace net {
 class URLRequestContextGetter;
 }
 
 namespace gcm {
 
 class GCMStatsRecorder;
 
-// Unregistration request is used to revoke registration IDs for applications
-// that were uninstalled and should no longer receive GCM messages. In case an
-// attempt to unregister fails, it will retry using the backoff policy.
+// Encapsulates the common logic applying to both GCM unregistration requests
+// and InstanceID delete-token requests. In case an attempt fails, it will retry
+// using the backoff policy.
 // TODO(fgorski): Consider sharing code with RegistrationRequest if possible.
 class GCM_EXPORT UnregistrationRequest : public net::URLFetcherDelegate {
  public:
   // Outcome of the response parsing. Note that these enums are consumed by a
   // histogram, so ordering should not be modified.
   enum Status {
     SUCCESS,                  // Unregistration completed successfully.
     URL_FETCHING_FAILED,      // URL fetching failed.
     NO_RESPONSE_BODY,         // No response body.
     RESPONSE_PARSING_FAILED,  // Failed to parse a meaningful output from
                               // response
                               // body.
     INCORRECT_APP_ID,         // App ID returned by the fetcher does not match
                               // request.
     INVALID_PARAMETERS,       // Request parameters were invalid.
     SERVICE_UNAVAILABLE,      // Unregistration service unavailable.
     INTERNAL_SERVER_ERROR,    // Internal server error happened during request.
     HTTP_NOT_OK,              // HTTP response code was not OK.
     UNKNOWN_ERROR,            // Unknown error.
     // NOTE: Always keep this entry at the end. Add new status types only
     // immediately above this line. Make sure to update the corresponding
     // histogram enum accordingly.
     UNREGISTRATION_STATUS_COUNT,
   };
 
   // Callback completing the unregistration request.
   typedef base::Callback<void(Status success)> UnregistrationCallback;
 
-  // Details of the of the Unregistration Request. All parameters are mandatory.
+  // Defines the common info about an unregistration/token-deletion request.
+  // All parameters are mandatory.
   struct GCM_EXPORT RequestInfo {
     RequestInfo(uint64 android_id,
                 uint64 security_token,
                 const std::string& app_id);
     ~RequestInfo();
 
     // Android ID of the device.
     uint64 android_id;
     // Security token of the device.
     uint64 security_token;
     // Application ID.
     std::string app_id;
   };
 
+  // Encapsulates the custom logic that is needed to build and process the
+  // unregistration request.
+  class GCM_EXPORT CustomRequestHandler {
+   public:
+    CustomRequestHandler();
+    virtual ~CustomRequestHandler();
+
+    virtual void BuildRequestBody(std::string* body) = 0;

[Nicolas Zea, 2015/05/26 16:39:15]

Comment when these are called? (i.e. this is called after the
UnregistrationRequest BuildRequestBody)

[jianli, 2015/05/26 20:49:39]

Done.

+    virtual Status ParseResponse(const net::URLFetcher* source) = 0;
+  };
+
   // Creates an instance of UnregistrationRequest. |callback| will be called
   // once registration has been revoked or there has been an error that makes
   // further retries pointless.
   UnregistrationRequest(
       const GURL& registration_url,
       const RequestInfo& request_info,
+      scoped_ptr<CustomRequestHandler> custom_request_handler,
       const net::BackoffEntry::Policy& backoff_policy,
       const UnregistrationCallback& callback,
       scoped_refptr<net::URLRequestContextGetter> request_context_getter,
       GCMStatsRecorder* recorder);
   ~UnregistrationRequest() override;
 
   // Starts an unregistration request.
   void Start();
 
+ private:
   // URLFetcherDelegate implementation.
   void OnURLFetchComplete(const net::URLFetcher* source) override;
 
- private:
+  void BuildRequestHeaders(std::string* extra_headers);
+  void BuildRequestBody(std::string* body);
+  Status ParseResponse(const net::URLFetcher* source);
+
   // Schedules a retry attempt and informs the backoff of previous request's
   // failure, when |update_backoff| is true.
   void RetryWithBackoff(bool update_backoff);
 
   UnregistrationCallback callback_;
   RequestInfo request_info_;
+  scoped_ptr<CustomRequestHandler> custom_request_handler_;
   GURL registration_url_;
 
   net::BackoffEntry backoff_entry_;
   scoped_refptr<net::URLRequestContextGetter> request_context_getter_;
   scoped_ptr<net::URLFetcher> url_fetcher_;
   base::TimeTicks request_start_time_;
 
   // Recorder that records GCM activities for debugging purpose. Not owned.
   GCMStatsRecorder* recorder_;
 
   base::WeakPtrFactory<UnregistrationRequest> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(UnregistrationRequest);
 };
 
 }  // namespace gcm
 
 #endif  // GOOGLE_APIS_GCM_ENGINE_UNREGISTRATION_REQUEST_H_