Create variations target that depends on base.

components/variations/variations_seed_processor.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 COMPONENTS_VARIATIONS_VARIATIONS_SEED_PROCESSOR_H_
+#define COMPONENTS_VARIATIONS_VARIATIONS_SEED_PROCESSOR_H_
+
+#include <string>
+
+#include "base/compiler_specific.h"
+#include "base/gtest_prod_util.h"
+#include "base/metrics/field_trial.h"
+#include "base/time/time.h"
+#include "base/version.h"
+#include "components/variations/proto/study.pb.h"
+#include "components/variations/proto/trials_seed.pb.h"
+
+namespace chrome_variations {
+
+// Helper class to instantiate field trials from a variations seed.
+class VariationsSeedProcessor {
+ public:
+  VariationsSeedProcessor();
+  virtual ~VariationsSeedProcessor();
+
+  // Creates field trials from the specified variations |seed|, based on the
+  // specified configuration (locale, current date, version and channel).
+  void CreateTrialsFromSeed(const TrialsSeed& seed,
+                            const std::string& locale,
+                            const base::Time& reference_date,
+                            const base::Version& version,
+                            Study_Channel channel);
+
+ private:
+  FRIEND_TEST_ALL_PREFIXES(VariationsSeedProcessorTest, CheckStudyChannel);
+  FRIEND_TEST_ALL_PREFIXES(VariationsSeedProcessorTest, CheckStudyLocale);
+  FRIEND_TEST_ALL_PREFIXES(VariationsSeedProcessorTest, CheckStudyPlatform);
+  FRIEND_TEST_ALL_PREFIXES(VariationsSeedProcessorTest, CheckStudyStartDate);
+  FRIEND_TEST_ALL_PREFIXES(VariationsSeedProcessorTest, CheckStudyVersion);
+  FRIEND_TEST_ALL_PREFIXES(VariationsSeedProcessorTest,
+                           CheckStudyVersionWildcards);
+  FRIEND_TEST_ALL_PREFIXES(VariationsSeedProcessorTest, ForceGroupWithFlag1);
+  FRIEND_TEST_ALL_PREFIXES(VariationsSeedProcessorTest, ForceGroupWithFlag2);
+  FRIEND_TEST_ALL_PREFIXES(VariationsSeedProcessorTest,
+                           ForceGroup_ChooseFirstGroupWithFlag);
+  FRIEND_TEST_ALL_PREFIXES(VariationsSeedProcessorTest,
+                           ForceGroup_DontChooseGroupWithFlag);
+  FRIEND_TEST_ALL_PREFIXES(VariationsSeedProcessorTest, IsStudyExpired);
+  FRIEND_TEST_ALL_PREFIXES(VariationsSeedProcessorTest, ValidateStudy);
+  FRIEND_TEST_ALL_PREFIXES(VariationsSeedProcessorTest, VariationParams);
+
+  // Checks whether a study is applicable for the given |channel| per |filter|.
+  bool CheckStudyChannel(const Study_Filter& filter, Study_Channel channel);
+
+  // Checks whether a study is applicable for the given |locale| per |filter|.
+  bool CheckStudyLocale(const Study_Filter& filter, const std::string& locale);
+
+  // Checks whether a study is applicable for the given |platform| per |filter|.
+  bool CheckStudyPlatform(const Study_Filter& filter, Study_Platform platform);
+
+  // Checks whether a study is applicable for the given date/time per |filter|.
+  bool CheckStudyStartDate(const Study_Filter& filter,
+                           const base::Time& date_time);
+
+  // Checks whether a study is applicable for the given version per |filter|.
+  bool CheckStudyVersion(const Study_Filter& filter,
+                         const base::Version& version);
+
+  // Creates and registers a field trial from the |study| data. Disables the
+  // trial if |is_expired| is true.
+  void CreateTrialFromStudy(const Study& study, bool is_expired);
+
+  // Checks whether |study| is expired using the given date/time.
+  bool IsStudyExpired(const Study& study, const base::Time& date_time);
+
+  // Returns whether |study| should be disabled according to its restriction
+  // parameters. Uses |version_info| for min / max version checks,
+  // |reference_date| for the start date check and |channel| for channel
+  // checks.
+  bool ShouldAddStudy(const Study& study,
+                      const std::string& locale,
+                      const base::Time& reference_date,
+                      const base::Version& version,
+                      Study_Channel channel);
+
+  // Validates the sanity of |study| and computes the total probability.
+  bool ValidateStudyAndComputeTotalProbability(
+      const Study& study,
+      base::FieldTrial::Probability* total_probability);
+
+  DISALLOW_COPY_AND_ASSIGN(VariationsSeedProcessor);
+};
+
+}  // namespace chrome_variations
+
+#endif  // COMPONENTS_VARIATIONS_VARIATIONS_SEED_PROCESSOR_H_