Log Preview Eligibility Reasons in UKM

Only non-ALLOWED values are logged.

Bug: 955472
Change-Id: I7480df4ce7597319fc6cbd18bc23da8e7c46625f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1597688Reviewed-by: Ryan Sturm <ryansturm@chromium.org>
Reviewed-by: Robert Kaplow <rkaplow@chromium.org>
Reviewed-by: Doug Arnett <dougarnett@chromium.org>
Commit-Queue: Robert Ogden <robertogden@chromium.org>
Cr-Commit-Position: refs/heads/master@{#658548}

chrome/browser/page_load_metrics/observers/previews_ukm_observer.cc

@@ -37,6 +37,16 @@ namespace {
 
 const char kOfflinePreviewsMimeType[] = "multipart/related";
 
+bool ShouldOptionalEligibilityReasonBeRecorded(
+    base::Optional<previews::PreviewsEligibilityReason> reason) {
+  if (!reason.has_value())
+    return false;
+
+  // Do not record ALLOWED values since we are only interested in recording
+  // reasons why a preview was not eligible to be shown.
+  return reason.value() != previews::PreviewsEligibilityReason::ALLOWED;
+}
+
 }  // namespace
 
 PreviewsUKMObserver::PreviewsUKMObserver()
@@ -106,16 +116,30 @@ PreviewsUKMObserver::OnCommit(content::NavigationHandle* navigation_handle,
                             previews::PreviewsType::RESOURCE_LOADING_HINTS) {
     resource_loading_hints_seen_ = true;
   }
-  if (previews_user_data &&
-      previews_user_data->cache_control_no_transform_directive()) {
+  if (previews_user_data->cache_control_no_transform_directive()) {
     origin_opt_out_occurred_ = true;
   }
-  if (previews_user_data && previews_user_data->server_lite_page_info()) {
+  if (previews_user_data->server_lite_page_info()) {
     navigation_restart_penalty_ =
         navigation_handle->NavigationStart() -
         previews_user_data->server_lite_page_info()->original_navigation_start;
   }
 
+  lite_page_eligibility_reason_ =
+      previews_user_data->EligibilityReasonForPreview(
+          previews::PreviewsType::LITE_PAGE);
+  lite_page_redirect_eligibility_reason_ =
+      previews_user_data->EligibilityReasonForPreview(
+          previews::PreviewsType::LITE_PAGE_REDIRECT);
+  noscript_eligibility_reason_ =
+      previews_user_data->EligibilityReasonForPreview(
+          previews::PreviewsType::NOSCRIPT);
+  resource_loading_hints_eligibility_reason_ =
+      previews_user_data->EligibilityReasonForPreview(
+          previews::PreviewsType::RESOURCE_LOADING_HINTS);
+  offline_eligibility_reason_ = previews_user_data->EligibilityReasonForPreview(
+      previews::PreviewsType::OFFLINE);
+
   return CONTINUE_OBSERVING;
 }
 
@@ -219,6 +243,30 @@ void PreviewsUKMObserver::RecordPreviewsTypes(
     builder.Setnavigation_restart_penalty(
         navigation_restart_penalty_->InMilliseconds());
   }
+
+  if (ShouldOptionalEligibilityReasonBeRecorded(
+          lite_page_eligibility_reason_)) {
+    builder.Setproxy_lite_page_eligibility_reason(
+        static_cast<int>(lite_page_eligibility_reason_.value()));
+  }
+  if (ShouldOptionalEligibilityReasonBeRecorded(
+          lite_page_redirect_eligibility_reason_)) {
+    builder.Setlite_page_redirect_eligibility_reason(
+        static_cast<int>(lite_page_redirect_eligibility_reason_.value()));
+  }
+  if (ShouldOptionalEligibilityReasonBeRecorded(noscript_eligibility_reason_)) {
+    builder.Setnoscript_eligibility_reason(
+        static_cast<int>(noscript_eligibility_reason_.value()));
+  }
+  if (ShouldOptionalEligibilityReasonBeRecorded(
+          resource_loading_hints_eligibility_reason_)) {
+    builder.Setresource_loading_hints_eligibility_reason(
+        static_cast<int>(resource_loading_hints_eligibility_reason_.value()));
+  }
+  if (ShouldOptionalEligibilityReasonBeRecorded(offline_eligibility_reason_)) {
+    builder.Setoffline_eligibility_reason(
+        static_cast<int>(offline_eligibility_reason_.value()));
+  }
   builder.Record(ukm::UkmRecorder::Get());
 }
 

chrome/browser/page_load_metrics/observers/previews_ukm_observer.h

@@ -10,6 +10,7 @@
 #include "base/sequence_checker.h"
 #include "base/time/time.h"
 #include "chrome/browser/page_load_metrics/page_load_metrics_observer.h"
+#include "components/previews/core/previews_black_list.h"
 #include "components/previews/core/previews_experiments.h"
 
 namespace content {
@@ -73,6 +74,16 @@ class PreviewsUKMObserver : public page_load_metrics::PageLoadMetricsObserver {
   bool origin_opt_out_occurred_ = false;
   bool save_data_enabled_ = false;
   bool previews_likely_ = false;
+  base::Optional<previews::PreviewsEligibilityReason>
+      lite_page_eligibility_reason_ = base::nullopt;
+  base::Optional<previews::PreviewsEligibilityReason>
+      lite_page_redirect_eligibility_reason_ = base::nullopt;
+  base::Optional<previews::PreviewsEligibilityReason>
+      noscript_eligibility_reason_ = base::nullopt;
+  base::Optional<previews::PreviewsEligibilityReason>
+      resource_loading_hints_eligibility_reason_ = base::nullopt;
+  base::Optional<previews::PreviewsEligibilityReason>
+      offline_eligibility_reason_ = base::nullopt;
   CoinFlipHoldbackResult coin_flip_result_ = CoinFlipHoldbackResult::kNotSet;
   base::Optional<base::TimeDelta> navigation_restart_penalty_ = base::nullopt;
 

tools/metrics/ukm/ukm.xml

@@ -5562,6 +5562,14 @@ be describing additional metrics about the same event.
       Set to 1 when a user is shown a lite page redirect in page load.
     </summary>
   </metric>
+  <metric name="lite_page_redirect_eligibility_reason">
+    <summary>
+      Set to the value of the last known reason a Lite Page Redirect preview was
+      not eligible on this page load. The value of this metric corresponds to
+      the PreviewsEligibilityReason enum. This metric is only set when it is
+      non-zero.
+    </summary>
+  </metric>
   <metric name="navigation_restart_penalty">
     <summary>
       Set to the number of milliseconds spent restarting navigations when a Lite
@@ -5574,6 +5582,22 @@ be describing additional metrics about the same event.
       Set to 1 when a user is shown a NoScript preview on a page load.
     </summary>
   </metric>
+  <metric name="noscript_eligibility_reason">
+    <summary>
+      Set to the value of the last known reason a NoScript preview was not
+      eligible on this page load. The value of this metric corresponds to the
+      PreviewsEligibilityReason enum. This metric is only set when it is
+      non-zero.
+    </summary>
+  </metric>
+  <metric name="offline_eligibility_reason">
+    <summary>
+      Set to the value of the last known reason an Offline preview was not
+      eligible on this page load. The value of this metric corresponds to the
+      PreviewsEligibilityReason enum. This metric is only set when it is
+      non-zero.
+    </summary>
+  </metric>
   <metric name="offline_preview">
     <summary>
       Set to 1 when a user is shown an offline preview page in page load.
@@ -5603,12 +5627,28 @@ be describing additional metrics about the same event.
       is impacted by the coin flip holdback.
     </summary>
   </metric>
+  <metric name="proxy_lite_page_eligibility_reason">
+    <summary>
+      Set to the value of the last known reason a Data Reduction Proxy Lite Page
+      preview was not eligible on this page load. The value of this metric
+      corresponds to the PreviewsEligibilityReason enum. This metric is only set
+      when it is non-zero.
+    </summary>
+  </metric>
   <metric name="resource_loading_hints">
     <summary>
       Set to 1 when a user is shown a resource loading hints based preview on a
       page load.
     </summary>
   </metric>
+  <metric name="resource_loading_hints_eligibility_reason">
+    <summary>
+      Set to the value of the last known reason a Resource Loading Hints preview
+      was not eligible on this page load. The value of this metric corresponds
+      to the PreviewsEligibilityReason enum. This metric is only set when it is
+      non-zero.
+    </summary>
+  </metric>
   <metric name="save_data_enabled">
     <summary>
       Set to 1 if the data saver feature was enabled in Chrome at the time of