// Copyright (c) 2012 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_OMNIBOX_OMNIBOX_FIELD_TRIAL_H_
#define CHROME_BROWSER_OMNIBOX_OMNIBOX_FIELD_TRIAL_H_
#include <map>
#include <set>
#include <string>
#include <vector>
#include "base/basictypes.h"
#include "base/gtest_prod_util.h"
#include "chrome/browser/autocomplete/autocomplete_input.h"
#include "chrome/common/autocomplete_match_type.h"
namespace base {
class TimeDelta;
}
// The set of parameters customizing the HUP scoring.
struct HUPScoringParams {
// A set of parameters describing how to cap a given count score. First,
// we apply a half-life based decay of the given count and then find the
// maximum relevance score in the corresponding bucket list.
class ScoreBuckets {
public:
// (decayed_count, max_relevance) pair.
typedef std::pair<double, int> CountMaxRelevance;
ScoreBuckets();
~ScoreBuckets();
// Computes a half-life time decay given the |elapsed_time|.
double HalfLifeTimeDecay(const base::TimeDelta& elapsed_time) const;
int relevance_cap() const { return relevance_cap_; }
void set_relevance_cap(int relevance_cap) {
relevance_cap_ = relevance_cap;
}
int half_life_days() const { return half_life_days_; }
void set_half_life_days(int half_life_days) {
half_life_days_ = half_life_days;
}
std::vector<CountMaxRelevance>& buckets() { return buckets_; }
const std::vector<CountMaxRelevance>& buckets() const { return buckets_; }
private:
// History matches with relevance score greater or equal to |relevance_cap_|
// are not affected by this experiment.
// Set to -1, if there is no relevance cap in place and all matches are
// subject to demotion.
int relevance_cap_;
// Half life time for a decayed count as measured since the last visit.
// Set to -1 if not used.
int half_life_days_;
// The relevance score caps for given decayed count values.
// Each pair (decayed_count, max_score) indicates what the maximum relevance
// score is of a decayed count equal or greater than decayed_count.
//
// Consider this example:
// [(1, 1000), (0.5, 500), (0, 100)]
// If decayed count is 2 (which is >= 1), the corresponding match's maximum
// relevance will be capped at 1000. In case of 0.5, the score is capped
// at 500. Anything below 0.5 is capped at 100.
//
// This list is sorted by the pair's first element in descending order.
std::vector<CountMaxRelevance> buckets_;
};
HUPScoringParams() : experimental_scoring_enabled(false) {}
bool experimental_scoring_enabled;
ScoreBuckets typed_count_buckets;
// Used only when the typed count is 0.
ScoreBuckets visited_count_buckets;
};
// This class manages the Omnibox field trials.
class OmniboxFieldTrial {
public:
// A mapping that contains multipliers indicating that matches of the
// specified type should have their relevance score multiplied by the
// given number. Omitted types are assumed to have multipliers of 1.0.
typedef std::map<AutocompleteMatchType::Type, float> DemotionMultipliers;
// A set of types that should not be demoted when they are the top match.
typedef std::set<AutocompleteMatchType::Type> UndemotableTopMatchTypes;
// Creates the static field trial groups.
// *** MUST NOT BE CALLED MORE THAN ONCE. ***
static void ActivateStaticTrials();
// Activates all dynamic field trials. The main difference between
// the autocomplete dynamic and static field trials is that the former
// don't require any code changes on the Chrome side as they are controlled
// on the server side. Chrome binary simply propagates all necessary
// information through the X-Client-Data header.
// This method, unlike ActivateStaticTrials(), may be called multiple times.
static void ActivateDynamicTrials();
// Returns a bitmap containing AutocompleteProvider::Type values
// that should be disabled in AutocompleteController.
// This method simply goes over all autocomplete dynamic field trial groups
// and looks for group names like "ProvidersDisabled_NNN" where NNN is
// an integer corresponding to a bitmap mask. All extracted bitmaps
// are OR-ed together and returned as the final result.
static int GetDisabledProviderTypes();
// Returns whether the user is in any dynamic field trial where the
// group has a the prefix |group_prefix|.
static bool HasDynamicFieldTrialGroupPrefix(const char *group_prefix);
// ---------------------------------------------------------
// For the suggest field trial.
// Populates |field_trial_hash| with hashes of the active suggest field trial
// names, if any.
static void GetActiveSuggestFieldTrialHashes(
std::vector<uint32>* field_trial_hash);
// ---------------------------------------------------------
// For the HistoryURL provider disable culling redirects field trial.
// Returns whether the user is in any group for this field trial.
// (Should always be true unless initialization went wrong.)
static bool InHUPCullRedirectsFieldTrial();
// Returns whether we should disable culling of redirects in
// HistoryURL provider.
static bool InHUPCullRedirectsFieldTrialExperimentGroup();
// ---------------------------------------------------------
// For the HistoryURL provider disable creating a shorter match
// field trial.
// Returns whether the user is in any group for this field trial.
// (Should always be true unless initialization went wrong.)
static bool InHUPCreateShorterMatchFieldTrial();
// Returns whether we should disable creating a shorter match in
// HistoryURL provider.
static bool InHUPCreateShorterMatchFieldTrialExperimentGroup();
// ---------------------------------------------------------
// For the AutocompleteController "stop timer" field trial.
// Returns the duration to be used for the AutocompleteController's stop
// timer. Returns the default value of 1.5 seconds if the stop timer
// override experiment isn't active or if parsing the experiment-provided
// duration fails.
static base::TimeDelta StopTimerFieldTrialDuration();
// ---------------------------------------------------------
// For the ZeroSuggestProvider field trial.
// Returns whether the user is in any field trial where the
// ZeroSuggestProvider should be used to get suggestions when the
// user clicks on the omnibox but has not typed anything yet.
static bool InZeroSuggestFieldTrial();
// Returns whether the user is in a ZeroSuggest field trial, but should
// show most visited URL instead. This is used to compare metrics of
// ZeroSuggest and most visited suggestions.
static bool InZeroSuggestMostVisitedFieldTrial();
// Returns whether the user is in a ZeroSuggest field trial and URL-based
// suggestions can continue to appear after the user has started typing.
static bool InZeroSuggestAfterTypingFieldTrial();
// Returns whether the user is in a ZeroSuggest field trial, but should
// show recently searched-for queries instead.
static bool InZeroSuggestPersonalizedFieldTrial();
// ---------------------------------------------------------
// For the ShortcutsScoringMaxRelevance experiment that's part of the
// bundled omnibox field trial.
// If the user is in an experiment group that, given the provided
// |current_page_classification| context, changes the maximum relevance
// ShortcutsProvider::CalculateScore() is supposed to assign, extract
// that maximum relevance score and put in in |max_relevance|. Returns
// true on a successful extraction. CalculateScore()'s return value is
// a product of this maximum relevance score and some attenuating factors
// that are all between 0 and 1. (Note that Shortcuts results may have
// their scores reduced later if the assigned score is higher than allowed
// for non-inlineable results. Shortcuts results are not allowed to be
// inlined.)
static bool ShortcutsScoringMaxRelevance(
AutocompleteInput::PageClassification current_page_classification,
int* max_relevance);
// ---------------------------------------------------------
// For the SearchHistory experiment that's part of the bundled omnibox
// field trial.
// Returns true if the user is in the experiment group that, given the
// provided |current_page_classification| context, scores search history
// query suggestions less aggressively so that they don't inline.
static bool SearchHistoryPreventInlining(
AutocompleteInput::PageClassification current_page_classification);
// Returns true if the user is in the experiment group that, given the
// provided |current_page_classification| context, disables all query
// suggestions from search history.
static bool SearchHistoryDisable(
AutocompleteInput::PageClassification current_page_classification);
// ---------------------------------------------------------
// For the DemoteByType experiment that's part of the bundled omnibox field
// trial.
// If the user is in an experiment group that, in the provided
// |current_page_classification| context, demotes the relevance scores
// of certain types of matches, populates the |demotions_by_type| map
// appropriately. Otherwise, sets |demotions_by_type| to its default
// value based on the context.
static void GetDemotionsByType(
AutocompleteInput::PageClassification current_page_classification,
DemotionMultipliers* demotions_by_type);
// Get the set of types that should not be demoted if they are the top
// match.
static UndemotableTopMatchTypes GetUndemotableTopTypes(
AutocompleteInput::PageClassification current_page_classification);
// ---------------------------------------------------------
// For the ReorderForLegalDefaultMatch experiment that's part of the
// bundled omnibox field trial.
// Returns true if the omnibox will reorder matches, in the provided
// |current_page_classification| context so that a match that's allowed to
// be the default match will appear first. This means AutocompleteProviders
// can score matches however they desire without regard to making sure the
// top match when all the matches from all providers are merged is a legal
// default match.
static bool ReorderForLegalDefaultMatch(
AutocompleteInput::PageClassification current_page_classification);
// ---------------------------------------------------------
// For the HistoryURL provider new scoring experiment that is part of the
// bundled omnibox field trial.
// Initializes the HUP |scoring_params| based on the active HUP scoring
// experiment. If there is no such experiment, this function simply sets
// |scoring_params|->experimental_scoring_enabled to false.
static void GetExperimentalHUPScoringParams(HUPScoringParams* scoring_params);
// For the HQPBookmarkValue experiment that's part of the
// bundled omnibox field trial.
// Returns the value an untyped visit to a bookmark should receive.
// Compare this value with the default of 1 for non-bookmarked untyped
// visits to pages and the default of 20 for typed visits. Returns
// 1 if the bookmark value experiment isn't active.
static int HQPBookmarkValue();
// ---------------------------------------------------------
// For the HQPDiscountFrecencyWhenFewVisits experiment that's part of
// the bundled omnibox field trial.
// Returns whether to discount the frecency score estimates when a
// URL has fewer than ScoredHistoryMatch::kMaxVisitsToScore visits.
// See comments in scored_history_match.h for details. Returns false
// if the discount frecency experiment isn't active.
static bool HQPDiscountFrecencyWhenFewVisits();
// ---------------------------------------------------------
// For the HQPAllowMatchInTLD experiment that's part of the
// bundled omnibox field trial.
// Returns true if HQP should allow an input term to match in the
// top level domain (e.g., .com) of a URL. Returns false if the
// allow match in TLD experiment isn't active.
static bool HQPAllowMatchInTLDValue();
// ---------------------------------------------------------
// For the HQPAllowMatchInScheme experiment that's part of the
// bundled omnibox field trial.
// Returns true if HQP should allow an input term to match in the
// scheme (e.g., http://) of a URL. Returns false if the allow
// match in scheme experiment isn't active.
static bool HQPAllowMatchInSchemeValue();
// ---------------------------------------------------------
// Exposed publicly for the sake of unittests.
static const char kBundledExperimentFieldTrialName[];
// Rule names used by the bundled experiment.
static const char kShortcutsScoringMaxRelevanceRule[];
static const char kSearchHistoryRule[];
static const char kDemoteByTypeRule[];
static const char kUndemotableTopTypeRule[];
static const char kReorderForLegalDefaultMatchRule[];
static const char kHQPBookmarkValueRule[];
static const char kHQPDiscountFrecencyWhenFewVisitsRule[];
static const char kHQPAllowMatchInTLDRule[];
static const char kHQPAllowMatchInSchemeRule[];
static const char kZeroSuggestRule[];
static const char kZeroSuggestVariantRule[];
// Rule values.
static const char kReorderForLegalDefaultMatchRuleDisabled[];
// Parameter names used by the HUP new scoring experiments.
static const char kHUPNewScoringEnabledParam[];
static const char kHUPNewScoringTypedCountRelevanceCapParam[];
static const char kHUPNewScoringTypedCountHalfLifeTimeParam[];
static const char kHUPNewScoringTypedCountScoreBucketsParam[];
static const char kHUPNewScoringVisitedCountRelevanceCapParam[];
static const char kHUPNewScoringVisitedCountHalfLifeTimeParam[];
static const char kHUPNewScoringVisitedCountScoreBucketsParam[];
private:
friend class OmniboxFieldTrialTest;
// The bundled omnibox experiment comes with a set of parameters
// (key-value pairs). Each key indicates a certain rule that applies in
// a certain context. The value indicates what the consequences of
// applying the rule are. For example, the value of a SearchHistory rule
// in the context of a search results page might indicate that we should
// prevent search history matches from inlining.
//
// This function returns the value associated with the |rule| that applies
// in the current context (which currently consists of |page_classification|
// and whether Instant Extended is enabled). If no such rule exists in the
// current context, fall back to the rule in various wildcard contexts and
// return its value if found. If the rule remains unfound in the global
// context, returns the empty string. For more details, including how we
// prioritize different wildcard contexts, see the implementation. How to
// interpret the value is left to the caller; this is rule-dependent.
static std::string GetValueForRuleInContext(
const std::string& rule,
AutocompleteInput::PageClassification page_classification);
DISALLOW_IMPLICIT_CONSTRUCTORS(OmniboxFieldTrial);
};
#endif // CHROME_BROWSER_OMNIBOX_OMNIBOX_FIELD_TRIAL_H_