Specify trigger-data matching

index.bs

@@ -744,6 +744,21 @@ It has the following constraints:
 * Every element's [=report window/start=] is equal to the previous element's [=report window/end=], if it exists.
 * There is at least one element in the list.
 
+<h3 id="trigger-data-matching-mode-header">Trigger-data matching mode</h3>
+
+A <dfn>trigger-data matching mode</dfn> is one of the following:
+
+<dl dfn-for="trigger-data matching mode">
+: "<dfn><code>exact</code></dfn>"
+:: [=event-level trigger configuration/Trigger data=] must be less than the
+    [=default trigger data cardinality=]. Otherwise, no event-level attribution
+    takes place.
+: "<dfn><code>modulus</code></dfn>"
+:: [=event-level trigger configuration/Trigger data=] is taken modulo the
+    [=default trigger data cardinality=].
+
+</dl>
+
 <h3 dfn-type=dfn>Attribution source</h3>
 
 An attribution source is a [=struct=] with the following items:
@@ -798,6 +813,8 @@ An attribution source is a [=struct=] with the following items:
 :: A [=boolean=].
 : <dfn>number of aggregatable reports</dfn>
 :: Number of [=aggregatable reports=] created for this [=attribution source=].
+: <dfn>trigger-data matching mode</dfn>
+:: A [=trigger-data matching mode=].
 
 </dl>
 
@@ -1059,6 +1076,7 @@ Possible values are:
 <li>"<dfn><code>trigger-event-excessive-reports</code></dfn>"
 <li>"<dfn><code>trigger-event-low-priority</code></dfn>"
 <li>"<dfn><code>trigger-event-no-matching-configurations</code></dfn>"
+<li>"<dfn><code>trigger-event-no-matching-trigger-data</code></dfn>"
 <li>"<dfn><code>trigger-event-noise</code></dfn>"
 <li>"<dfn><code>trigger-event-report-window-not-started</code></dfn>"
 <li>"<dfn><code>trigger-event-report-window-passed</code></dfn>"
@@ -1965,7 +1983,11 @@ To <dfn noexport>parse source-registration JSON</dfn> given a [=byte sequence=]
 1. Let |epsilon| be the user agent's [=randomized response epsilon=].
 1. If the result of [=computing the channel capacity of a source=] with |randomizedResponseConfig| and |epsilon| is greater than
     [=max event-level channel capacity per source=][|sourceType|], return null.
-
+1. Let |triggerDataMatchingMode| be "<code>[=trigger-data matching mode/modulus=]</code>".
+1. If |value|["`trigger_data_matching`"] [=map/exists=]:
+    1. If |value|["`trigger_data_matching`"] is not a [=string=], return null.
+    1. If |value|["`trigger_data_matching`"] is not a [=trigger-data matching mode=], return null.
+    1. Set |triggerDataMatchingMode| to |value|["`trigger_data_matching`"].
 1. Let |source| be a new [=attribution source=] struct whose items are:
 
     : [=attribution source/source identifier=]
@@ -2006,6 +2028,8 @@ To <dfn noexport>parse source-registration JSON</dfn> given a [=byte sequence=]
     :: 0
     : [=attribution source/debug reporting enabled=]
     :: |debugReportingEnabled|
+    : [=attribution source/trigger-data matching mode=]
+    :: |triggerDataMatchingMode|
 1. Return |source|.
 
 Issue: Determine proper charset-handling for the JSON header value.
@@ -2102,6 +2126,7 @@ a [=trigger state=] |triggerState|:
     :: "<code>[=aggregatable source registration time configuration/exclude=]</code>"
 1. Let |fakeReport| be the result of running [=obtain an event-level report=] with |source|,
     |fakeTrigger|, and |fakeConfig|.
+1. [=Assert=]: |fakeReport| is not null.
 1. Set |fakeReport|'s [=event-level report/report time=] to the result of
     running [=obtain the report time at a window=] with |source| and
     |triggerState|'s [=trigger state/report window=].
@@ -2760,6 +2785,11 @@ To <dfn>trigger event-level attribution</dfn> given an [=attribution trigger=] |
     return it.
 1. Let |report| be the result of running [=obtain an event-level report=] with |sourceToAttribute|, |trigger|,
     and |matchedConfig|.
+1. If |report| is null:
+    1. Let |debugData| be the result of running [=obtain debug data on trigger registration=]
+        with "<code>[=trigger debug data type/trigger-event-no-matching-trigger-data=]</code>", |trigger|, |sourceToAttribute| and
+        [=obtain debug data on trigger registration/report=] set to null.
+    1. Return the [=triggering result=] ("<code>[=triggering status/dropped=]</code>", |debugData|).
 1. If |sourceToAttribute|'s [=attribution source/event-level attributable=] value
     is false:
      1. Let |debugData| be the result of running [=obtain debug data on trigger registration=]
@@ -3020,15 +3050,23 @@ To <dfn>obtain an aggregatable report delivery time</dfn> given a [=moment=]
 To <dfn>obtain an event-level report</dfn> given an [=attribution source=] |source|, an [=attribution trigger=]
 |trigger|, and an [=event-level trigger configuration=] |config|:
 
+1. Let |triggerData| be |config|'s [=event-level trigger configuration/trigger data=].
 1. Let |triggerDataCardinality| be the user agent's [=default trigger data cardinality=][|source|'s [=attribution source/source type=]].
+1. If |source|'s [=attribution source/trigger-data matching mode=] is:
+    <dl class="switch">
+    : "<code>[=trigger-data matching mode/exact=]</code>":
+    :: If |triggerData| is greater than or equal to |triggerDataCardinality|, return null.
+    : "<code>[=trigger-data matching mode/modulus=]</code>":
+    :: Set |triggerData| to the remainder when dividing |triggerData| by |triggerDataCardinality|.
+
+    </dl>
 1. Let |reportTime| be the result of running [=obtain an event-level report delivery time=] with |source| and |trigger|'s [=attribution trigger/trigger time=].
 1. Let |report| be a new [=event-level report=] struct whose items are:
 
     : [=event-level report/event ID=]
     :: |source|'s [=attribution source/event ID=].
     : [=event-level report/trigger data=]
-    :: The remainder when dividing |config|'s [=event-level trigger configuration/trigger data=] by
-        |triggerDataCardinality|.
+    :: |triggerData|
     : [=event-level report/randomized trigger rate=]
     :: |source|'s [=attribution source/randomized trigger rate=].
     : [=event-level report/reporting origin=]