core(lantern): refactor Trace Engine specific code to file

GoogleChrome · Jun 10, 2024 · 2bf6074 · 2bf6074
1 parent f8063f8
commit 2bf6074
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Showing 6 changed files with 474 additions and 455 deletions.
diff --git a/core/computed/metrics/lantern-metric.js b/core/computed/metrics/lantern-metric.js
@@ -10,7 +10,7 @@ import {LoadSimulator} from '../load-simulator.js';
 import {ProcessedNavigation} from '../processed-navigation.js';
 import {PageDependencyGraph} from '../page-dependency-graph.js';
 import {TraceEngineResult} from '../trace-engine-result.js';
-import {createProcessedNavigation} from '../../lib/lantern/lantern.js';
+import {createProcessedNavigation} from '../../lib/lantern/trace-engine-computation-data.js';
 
 /**
  * @param {LH.Artifacts.MetricComputationDataInput} data

diff --git a/core/computed/page-dependency-graph.js b/core/computed/page-dependency-graph.js
@@ -10,6 +10,7 @@ import {NetworkRequest} from '../lib/network-request.js';
 import {ProcessedTrace} from './processed-trace.js';
 import {NetworkRecords} from './network-records.js';
 import {TraceEngineResult} from './trace-engine-result.js';
+import * as TraceEngineComputationData from '../lib/lantern/trace-engine-computation-data.js';
 
 /** @typedef {import('../lib/lantern/base-node.js').Node<LH.Artifacts.NetworkRequest>} Node */
 
@@ -28,8 +29,9 @@ class PageDependencyGraph {
 
     if (data.fromTrace) {
       const traceEngineResult = await TraceEngineResult.request({trace}, context);
-      const {graph} = await LanternPageDependencyGraph.createGraphFromTrace(
-        trace, traceEngineResult, URL);
+      const requests = TraceEngineComputationData.createNetworkRequests(trace, traceEngineResult);
+      const graph =
+        TraceEngineComputationData.createGraph(requests, trace, traceEngineResult, URL);
       return graph;
     }
 

diff --git a/core/lib/lantern/lantern.js b/core/lib/lantern/lantern.js
@@ -4,11 +4,6 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-import * as Lantern from './types/lantern.js';
-
-/** @typedef {import('@paulirish/trace_engine/models/trace/handlers/PageLoadMetricsHandler.js').MetricName} MetricName */
-/** @typedef {import('@paulirish/trace_engine/models/trace/handlers/PageLoadMetricsHandler.js').MetricScore} MetricScore */
-
 /** @type {LH.Util.SelfMap<LH.Crdp.Network.ResourceType>} */
 const NetworkRequestTypes = {
   XHR: 'XHR',
@@ -31,48 +26,6 @@ const NetworkRequestTypes = {
   Prefetch: 'Prefetch',
 };
 
-/**
- * @param {LH.Artifacts.TraceEngineResult} traceEngineResult
- * @return {Lantern.Simulation.ProcessedNavigation}
- */
-function createProcessedNavigation(traceEngineResult) {
-  const Meta = traceEngineResult.data.Meta;
-  const frameId = Meta.mainFrameId;
-  const scoresByNav = traceEngineResult.data.PageLoadMetrics.metricScoresByFrameId.get(frameId);
-  if (!scoresByNav) {
-    throw new Error('missing metric scores for main frame');
-  }
-
-  const lastNavigationId = Meta.mainFrameNavigations.at(-1)?.args.data?.navigationId;
-  const scores = lastNavigationId && scoresByNav.get(lastNavigationId);
-  if (!scores) {
-    throw new Error('missing metric scores for specified navigation');
-  }
-
-  /** @param {MetricName} metric */
-  const getTimestampOrUndefined = metric => {
-    const metricScore = scores.get(metric);
-    if (!metricScore?.event) return;
-    return metricScore.event.ts;
-  };
-  /** @param {MetricName} metric */
-  const getTimestamp = metric => {
-    const metricScore = scores.get(metric);
-    if (!metricScore?.event) throw new Error(`missing metric: ${metric}`);
-    return metricScore.event.ts;
-  };
-  // TODO: should use `MetricName.LCP`, but it is a const enum.
-  const FCP = /** @type {MetricName} */('FCP');
-  const LCP = /** @type {MetricName} */('LCP');
-  return {
-    timestamps: {
-      firstContentfulPaint: getTimestamp(FCP),
-      largestContentfulPaint: getTimestampOrUndefined(LCP),
-    },
-  };
-}
-
 export {
   NetworkRequestTypes,
-  createProcessedNavigation,
 };