Omnibox - Zero Suggest - Log When/Whether Contextual Search is Possible

components/omnibox/browser/zero_suggest_provider.cc

Index: components/omnibox/browser/zero_suggest_provider.cc
diff --git a/components/omnibox/browser/zero_suggest_provider.cc b/components/omnibox/browser/zero_suggest_provider.cc
index 1a5d022917791cebdb92f6881df8209ef52197c7..9c33a77db1fccc536ba69db45daab9c4f76e447b 100644
--- a/components/omnibox/browser/zero_suggest_provider.cc
+++ b/components/omnibox/browser/zero_suggest_provider.cc
@@ -19,6 +19,7 @@
 #include "components/data_use_measurement/core/data_use_user_data.h"
 #include "components/history/core/browser/history_types.h"
 #include "components/history/core/browser/top_sites.h"
+#include "components/metrics/proto/omnibox_event.pb.h"
 #include "components/metrics/proto/omnibox_input_type.pb.h"
 #include "components/omnibox/browser/autocomplete_classifier.h"
 #include "components/omnibox/browser/autocomplete_input.h"
@@ -43,19 +44,30 @@
 
 namespace {
 
+// Represents whether ZeroSuggestProvider is allowed to display contextual
+// suggestions on focus, and if not, why not.
+// These values are written to logs.  New enum values can be added, but existing
+// enums must never be renumbered or deleted and reused.
+enum class ZeroSuggestEligibility {
+  ELIGIBLE = 0,
+  // URL_INELIGIBLE would be ELIGIBLE except some property of the current URL
+  // itself prevents ZeroSuggest from triggering.
+  URL_INELIGIBLE = 1,
+  GENERALLY_INELIGIBLE = 2,
+  ELIGIBLE_MAX_VALUE
+};
+
 // TODO(hfung): The histogram code was copied and modified from
 // search_provider.cc.  Refactor and consolidate the code.
 // We keep track in a histogram how many suggest requests we send, how
 // many suggest requests we invalidate (e.g., due to a user typing
 // another character), and how many replies we receive.
-// *** ADD NEW ENUMS AFTER ALL PREVIOUSLY DEFINED ONES! ***
-//     (excluding the end-of-list enum value)
-// We do not want values of existing enums to change or else it screws
-// up the statistics.
+// These values are written to logs.  New enum values can be added, but existing
+// enums must never be renumbered or deleted and reused.
 enum ZeroSuggestRequestsHistogramValue {
   ZERO_SUGGEST_REQUEST_SENT = 1,
-  ZERO_SUGGEST_REQUEST_INVALIDATED,
-  ZERO_SUGGEST_REPLY_RECEIVED,
+  ZERO_SUGGEST_REQUEST_INVALIDATED = 2,
+  ZERO_SUGGEST_REPLY_RECEIVED = 3,
   ZERO_SUGGEST_MAX_REQUEST_HISTOGRAM_VALUE
 };
 
@@ -68,6 +80,9 @@ void LogOmniboxZeroSuggestRequest(
 // Relevance value to use if it was not set explicitly by the server.
 const int kDefaultZeroSuggestRelevance = 100;
 
+// Used for testing whether zero suggest is ever available.
+std::string kArbitraryInsecureUrlString = "http://www.google.com/";
+
 }  // namespace
 
 // static
@@ -101,32 +116,37 @@ void ZeroSuggestProvider::Start(const AutocompleteInput& input,
   current_query_ = input.current_url().spec();
   current_page_classification_ = input.current_page_classification();
   current_url_match_ = MatchForCurrentURL();
-  TemplateURLService* template_url_service = client()->GetTemplateURLService();
-
-  const TemplateURL* default_provider =
-      template_url_service->GetDefaultSearchProvider();
-  if (default_provider == NULL)
-    return;
 
-  base::string16 prefix;
-  TemplateURLRef::SearchTermsArgs search_term_args(prefix);
-  std::string url_string;
-  if (OmniboxFieldTrial::InZeroSuggestRedirectToChromeFieldTrial()) {
-    url_string = OmniboxFieldTrial::ZeroSuggestRedirectToChromeServerAddress();
-  } else {
-    url_string = default_provider->suggestions_url_ref().ReplaceSearchTerms(
-        search_term_args, template_url_service->search_terms_data());
-  }
+  std::string url_string = GetContextualSuggestionsUrl();
   GURL suggest_url(url_string);
-
   if (!suggest_url.is_valid())
     return;
 
   // No need to send the current page URL in personalized suggest or
   // most visited field trials.
-  if (CanSendURL(input.current_url(), suggest_url, default_provider,
+  const TemplateURLService* template_url_service =
+      client()->GetTemplateURLService();
+  const TemplateURL* default_provider =
+      template_url_service->GetDefaultSearchProvider();
+  const bool can_send_current_url =
+      CanSendURL(input.current_url(), suggest_url, default_provider,
                  current_page_classification_,
-                 template_url_service->search_terms_data(), client()) &&
+                 template_url_service->search_terms_data(), client());
+  GURL arbitrary_insecure_url(kArbitraryInsecureUrlString);
+  ZeroSuggestEligibility eligibility = ZeroSuggestEligibility::ELIGIBLE;
+  if (!can_send_current_url) {
+    const bool can_send_ordinary_url =
+        CanSendURL(arbitrary_insecure_url, suggest_url, default_provider,
+                   current_page_classification_,
+                   template_url_service->search_terms_data(), client());
+    eligibility = can_send_ordinary_url
+                      ? ZeroSuggestEligibility::URL_INELIGIBLE
+                      : ZeroSuggestEligibility::GENERALLY_INELIGIBLE;
+  }
+  UMA_HISTOGRAM_ENUMERATION(
+      "Omnibox.ZeroSuggest.Eligible.OnFocus", static_cast<int>(eligibility),
+      static_cast<int>(ZeroSuggestEligibility::ELIGIBLE_MAX_VALUE));
+  if (can_send_current_url &&
       !OmniboxFieldTrial::InZeroSuggestPersonalizedFieldTrial() &&
       !OmniboxFieldTrial::InZeroSuggestMostVisitedFieldTrial()) {
     // Update suggest_url to include the current_page_url.
@@ -136,6 +156,8 @@ void ZeroSuggestProvider::Start(const AutocompleteInput& input,
           OmniboxFieldTrial::ZeroSuggestRedirectToChromeAdditionalFields();
       suggest_url = GURL(url_string);
     } else {
+      base::string16 prefix;
+      TemplateURLRef::SearchTermsArgs search_term_args(prefix);
       search_term_args.current_page_url = current_query_;
       suggest_url =
           GURL(default_provider->suggestions_url_ref().ReplaceSearchTerms(
@@ -209,6 +231,23 @@ ZeroSuggestProvider::ZeroSuggestProvider(
       results_from_cache_(false),
       waiting_for_most_visited_urls_request_(false),
       weak_ptr_factory_(this) {
+  // Record whether contextual zero suggest is possible for this user / profile.
+  const TemplateURLService* template_url_service =
+      client->GetTemplateURLService();
+  // Template URL service can be null in tests.
+  if (template_url_service != nullptr) {
+    GURL suggest_url(GetContextualSuggestionsUrl());
+    // To check whether this is allowed, use an arbitrary insecure (http) URL
+    // as the URL we'd want suggestions for.  The value of OTHER as the current
+    // page classification is to correspond with that URL.
+    UMA_HISTOGRAM_BOOLEAN(
+        "Omnibox.ZeroSuggest.Eligible.OnProfileOpen",
+        suggest_url.is_valid() &&
+            CanSendURL(GURL(kArbitraryInsecureUrlString), suggest_url,
+                       template_url_service->GetDefaultSearchProvider(),
+                       metrics::OmniboxEventProto::OTHER,
+                       template_url_service->search_terms_data(), client));
+  }
 }
 
 ZeroSuggestProvider::~ZeroSuggestProvider() {
@@ -479,6 +518,24 @@ bool ZeroSuggestProvider::ShouldShowNonContextualZeroSuggest(
   return true;
 }
 
+std::string ZeroSuggestProvider::GetContextualSuggestionsUrl() const {
+  // Without a default search provider, refuse to do anything (even if the user
+  // is in the redirect-to-chrome field trial).
+  const TemplateURLService* template_url_service =
+      client()->GetTemplateURLService();
+  const TemplateURL* default_provider =
+      template_url_service->GetDefaultSearchProvider();
+  if (default_provider == nullptr)
+    return std::string();
+
+  if (OmniboxFieldTrial::InZeroSuggestRedirectToChromeFieldTrial())
+    return OmniboxFieldTrial::ZeroSuggestRedirectToChromeServerAddress();
+  base::string16 prefix;
+  TemplateURLRef::SearchTermsArgs search_term_args(prefix);
+  return default_provider->suggestions_url_ref().ReplaceSearchTerms(
+      search_term_args, template_url_service->search_terms_data());
+}
+
 void ZeroSuggestProvider::MaybeUseCachedSuggestions() {
   if (!OmniboxFieldTrial::InZeroSuggestPersonalizedFieldTrial())
     return;