New architecture of the activity logging: Policies for summarization (and compression)

chrome/browser/extensions/activity_log/activity_log_policy.h

+// Copyright $YEAR 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 CHROME_BROWSER_EXTENSIONS_ACTIVITY_LOG_ACTIVITY_LOG_POLICY_H_
+#define CHROME_BROWSER_EXTENSIONS_ACTIVITY_LOG_ACTIVITY_LOG_POLICY_H_
+
+#include <string>
+#include <vector>
+
+#include "base/bind.h"
+#include "base/bind_helpers.h"
+#include "base/callback.h"
+#include "base/files/file_path.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/timer.h"
+#include "base/values.h"
+#include "content/public/browser/browser_thread.h"
+#include "chrome/browser/extensions/activity_log/activity_actions.h"
+#include "googleurl/src/gurl.h"
+
+class Profile;
+class GURL;
+
+namespace extensions {
+
+class Extension;
+
+// Abstract class for summarizing data and storing it into the database.  Any
+// subclass should implement the following functionality:
+//
+// (1) Summarization (and possibly) compression of data
+// (2) Periodical saving of the in-memory state with the database
+// (3) Periodical database cleanup
+//
+// Since every policy implementation might summarize data differently, the
+// database implementation is policy-specific and therefore completely
+// encapsulated in the policy class.
+class ActivityLogPolicy {

[felt, 2013/05/24 18:43:38]

Can you please specify that all of these methods can be called on the UI thread,
because all DB operations are dispatched via the ActivityDatabase.

[dbabic, 2013/05/28 21:11:49]

Done.

+  public:
+    enum PolicyType {
+      POLICY_FULLSTREAM,
+      POLICY_NOARGS,
+    };
+
+    enum ActionType {
+      ACTION_API,
+      ACTION_EVENT,
+      ACTION_BLOCKED,
+      ACTION_DOM,
+      ACTION_WEB_REQUEST,
+    };
+
+    // For all subclasses, add all the key types they might support here.
+    // The actual key is returned by calling GetKey(KeyType).  The subclasses
+    // are free to return an empty string for keys they don't support.
+    // For every key added here, you should update the GetKey member function
+    // for at least one policy.
+    enum KeyType {
+      PARAM_KEY_REASON,     // Why an action was blocked
+      PARAM_KEY_DOM_ACTION, // Getter, Setter, Method,...
+      PARAM_KEY_URL_TITLE,
+      PARAM_KEY_DETAILS_STRING,
+    };
+
+    explicit ActivityLogPolicy(Profile* profile,
+                               content::BrowserThread::ID thread_id);
+    virtual ~ActivityLogPolicy();
+
+    // Updates the internal state of the model summarizing actions and possibly
+    // writes to the database.  Implements the default policy storing internal
+    // state to memory every 5 min.
+    virtual void ProcessAction(
+        ActionType action_type,
+        const Extension& extension,
+        const std::string& name,              // action name
+        const GURL* gurl,                     // target URL
+        const base::ListValue* args,          // arguments
+        const base::DictionaryValue* details  // details
+    ) = 0;
+
+    // Saves the internal state in the memory into the database.  Must be
+    // written so as to be thread-safe, as it can be called from a timer that
+    // saves state periodically and explicitly.
+    virtual void SaveState() { }
+
+    // Pass the parameters as a set of key-value pairs and return data back via
+    // a callback passing results as a set of key-value pairs.  The keys are
+    // policy-specific.
+    virtual void ReadData(
+        const base::DictionaryValue& parameters,
+        const base::Callback<void(scoped_ptr<base::DictionaryValue>)>& callback)
+        const {}
+
+    // TODO(felt,dbabic) This is overly specific to the current implementation
+    // of the FullStreamUIPolicy.  We should refractor it to use the above

[felt, 2013/05/24 18:43:38]

"refractor" -> "refactor"

[dbabic, 2013/05/28 21:11:49]

Done.

+    // more general member function.
+    virtual void ReadData(
+        const std::string& extension_id,
+        const int day,
+        const base::Callback<void(
+            scoped_ptr<std::vector<scoped_refptr<Action> > >)>& callback)
+        const {}
+
+    // For testing purposes --- disables periodic state saving, making the
+    // behavior reproducible.
+    void SetSaveStateOnRequestOnly();
+
+    virtual void GetKey(KeyType key_id, std::string& key_string) const;
+
+  protected:
+    // The Schedule methods dispatch the calls to the database on a
+    // separate thread. We dispatch to the UI thread if the DB thread doesn't
+    // exist, which should only happen in tests where there is no DB thread.
+    template<typename DatabaseType, typename DatabaseFunc>
+    void ScheduleAndForget(DatabaseType db, DatabaseFunc func) {
+      content::BrowserThread::PostTask(
+          dispatch_thread_,
+          FROM_HERE,
+          base::Bind(func, base::Unretained(db)));
+    }
+
+    template<typename DatabaseType, typename DatabaseFunc, typename ArgA>
+    void ScheduleAndForget(DatabaseType db, DatabaseFunc func, ArgA a) {
+      content::BrowserThread::PostTask(
+          dispatch_thread_,
+          FROM_HERE,
+          base::Bind(func, base::Unretained(db), a));
+    }
+
+    template<typename DatabaseType, typename DatabaseFunc,
+        typename ArgA, typename ArgB>
+    void ScheduleAndForget(DatabaseType db, DatabaseFunc func, ArgA a, ArgB b) {
+      content::BrowserThread::PostTask(
+          dispatch_thread_,
+          FROM_HERE,
+          base::Bind(func, base::Unretained(db), a, b));
+    }
+
+    base::FilePath profile_base_path_;
+    base::RepeatingTimer<ActivityLogPolicy> timer_;
+    // Normally the DB thread. In some cases (tests), it might not exist
+    // we dispatch to the UI thread.
+    content::BrowserThread::ID dispatch_thread_;
+};
+
+} // End of the extensions namespace
+
+#endif  // CHROME_BROWSER_EXTENSIONS_ACTIVITY_LOG_ACTIVITY_LOG_POLICY_H_