Bug 1821189 - Associate provenance attribution with installation.first_seen event r=nalexander

We can't add the provenance data to the `installation.first_seen` extra data because it is already at its maximum number of keys. So instead we will add the `installation.first_seen_prov_ext` event which will be sent at the same time as `installation.first_seen` and will contain provenance attribution data in its extras object.

Differential Revision: https://phabricator.services.mozilla.com/D172520

browser/components/attribution/ProvenanceData.sys.mjs

@@ -441,6 +441,15 @@ export var ProvenanceData = {
   /**
    * Only submits telemetry once, no matter how many times it is called.
    * Has no effect on OSs where provenance data is not supported.
+   *
+   * @returns An object indicating the values submitted. Keys may not match the
+   *          Scalar names since the returned object is intended to be suitable
+   *          for use as a Telemetry Event's `extra` object, which has shorter
+   *          limits for extra key names than the limits for Scalar names.
+   *          Values will be converted to strings since Telemetry Event's
+   *          `extra` objects must have string values.
+   *          On platforms that do not support provenance data, this will always
+   *          return an empty object.
    */
   async submitProvenanceTelemetry() {
     if (gTelemetryPromise) {
@@ -448,21 +457,31 @@ export var ProvenanceData = {
     }
     gTelemetryPromise = (async () => {
       const errorValue = "error";
+
+      let extra = {};
+
       let provenance = await this.readZoneIdProvenanceFile();
       if (!provenance) {
-        return;
+        return extra;
       }
 
-      Services.telemetry.scalarSet(
+      let setTelemetry = (scalarName, extraKey, value) => {
+        Services.telemetry.scalarSet(scalarName, value);
+        extra[extraKey] = value.toString();
+      };
+
+      setTelemetry(
         "attribution.provenance.data_exists",
+        "data_exists",
         !provenance.readProvenanceError
       );
       if (provenance.readProvenanceError) {
-        return;
+        return extra;
       }
 
-      Services.telemetry.scalarSet(
+      setTelemetry(
         "attribution.provenance.file_system",
+        "file_system",
         provenance.fileSystem ?? errorValue
       );
 
@@ -475,42 +494,50 @@ export var ProvenanceData = {
           provenance.readZoneIdError == "openFile" &&
           provenance.readZoneIdErrorCode == ERROR_FILE_NOT_FOUND
         );
-      Services.telemetry.scalarSet(
+      setTelemetry(
         "attribution.provenance.ads_exists",
+        "ads_exists",
         ads_exists
       );
       if (!ads_exists) {
-        return;
+        return extra;
       }
 
-      Services.telemetry.scalarSet(
+      setTelemetry(
         "attribution.provenance.security_zone",
+        "security_zone",
         "zoneId" in provenance ? provenance.zoneId.toString() : errorValue
       );
 
       let haveReferrerUrl = URL.isInstance(provenance.referrerUrl);
-      Services.telemetry.scalarSet(
+      setTelemetry(
         "attribution.provenance.referrer_url_exists",
+        "refer_url_exist",
         haveReferrerUrl
       );
       if (haveReferrerUrl) {
-        Services.telemetry.scalarSet(
+        setTelemetry(
           "attribution.provenance.referrer_url_is_mozilla",
+          "refer_url_moz",
           provenance.referrerUrlIsMozilla
         );
       }
 
       let haveHostUrl = URL.isInstance(provenance.hostUrl);
-      Services.telemetry.scalarSet(
+      setTelemetry(
         "attribution.provenance.host_url_exists",
+        "host_url_exist",
         haveHostUrl
       );
       if (haveHostUrl) {
-        Services.telemetry.scalarSet(
+        setTelemetry(
           "attribution.provenance.host_url_is_mozilla",
+          "host_url_moz",
           provenance.hostUrlIsMozilla
         );
       }
+
+      return extra;
     })();
     return gTelemetryPromise;
   },

browser/components/attribution/test/xpcshell/test_zoneId_parsing.js

@@ -27,6 +27,20 @@ add_setup(function setup() {
 // If `iniFileContents` is passed as `null`, we will simulate an error reading
 // the INI.
 async function testProvenance(iniFileContents, testFn, telemetryTestFn) {
+  // The extra data returned by `ProvenanceData.submitProvenanceTelemetry` uses
+  // names that don't actually match the scalar names due to name length
+  // restrictions.
+  let scalarToExtraKeyMap = {
+    "attribution.provenance.data_exists": "data_exists",
+    "attribution.provenance.file_system": "file_system",
+    "attribution.provenance.ads_exists": "ads_exists",
+    "attribution.provenance.security_zone": "security_zone",
+    "attribution.provenance.referrer_url_exists": "refer_url_exist",
+    "attribution.provenance.referrer_url_is_mozilla": "refer_url_moz",
+    "attribution.provenance.host_url_exists": "host_url_exist",
+    "attribution.provenance.host_url_is_mozilla": "host_url_moz",
+  };
+
   if (iniFileContents == null) {
     AttributionIOUtils.readUTF8 = async path => {
       throw new Error("test error: simulating provenance file read error");
@@ -40,13 +54,15 @@ async function testProvenance(iniFileContents, testFn, telemetryTestFn) {
   }
   if (telemetryTestFn) {
     Services.telemetry.clearScalars();
-    await ProvenanceData.submitProvenanceTelemetry();
+    let extras = await ProvenanceData.submitProvenanceTelemetry();
     let scalars = Services.telemetry.getSnapshotForScalars(
       "new-profile",
       false /* aClear */
     ).parent;
     let checkScalar = (scalarName, expectedValue) => {
       TelemetryTestUtils.assertScalar(scalars, scalarName, expectedValue);
+      let extraKey = scalarToExtraKeyMap[scalarName];
+      Assert.equal(extras[extraKey], expectedValue.toString());
     };
     telemetryTestFn(checkScalar);
   }