commit 067df2781ede4416a335aed0e36a5765bccc337a
parent a2afd88a0b68ac666df7ddc44625149adc7454f1
Author: Randell Jesup <rjesup@mozilla.com>
Date: Thu, 4 Dec 2025 14:47:48 +0000
Bug 2003981: test decodedBodySize for performanceResourceTiming r=necko-reviewers,valentin
Differential Revision: https://phabricator.services.mozilla.com/D275033
Diffstat:
1 file changed, 186 insertions(+), 0 deletions(-)
diff --git a/testing/web-platform/tests/resource-timing/decoded-body-size-compressed.https.html b/testing/web-platform/tests/resource-timing/decoded-body-size-compressed.https.html
@@ -0,0 +1,186 @@
+<!DOCTYPE html>
+<html>
+<head>
+ <meta charset="utf-8">
+ <meta name="timeout" content="long"/>
+ <title>PerformanceResourceTiming.decodedBodySize for compressed resources</title>
+ <link rel="help" href="https://www.w3.org/TR/resource-timing-2/#dom-performanceresourcetiming-decodedbodysize" />
+ <script src="/resources/testharness.js"></script>
+ <script src="/resources/testharnessreport.js"></script>
+ <script src="/fetch/compression-dictionary/resources/compression-dictionary-util.sub.js"></script>
+ <script>
+ const waitForResourceTiming = (url) => {
+ return new Promise(resolve => {
+ const observer = new PerformanceObserver((list) => {
+ const entries = list.getEntries();
+ for (const entry of entries) {
+ if (entry.name.includes(url)) {
+ observer.disconnect();
+ resolve(entry);
+ }
+ }
+ });
+ observer.observe({ entryTypes: ["resource"] });
+ });
+ };
+
+ promise_test(async (t) => {
+ const url = "/resource-timing/resources/gzip_xml.py";
+ const expectedDecodedSize = 125;
+
+ const timingPromise = waitForResourceTiming(url);
+ const response = await fetch(url);
+ await response.text();
+ const entry = await timingPromise;
+
+ assert_equals(entry.decodedBodySize, expectedDecodedSize,
+ "decodedBodySize should match the uncompressed XML file size");
+ assert_greater_than(entry.encodedBodySize, 0,
+ "encodedBodySize should be non-zero");
+ }, "decodedBodySize for gzip-compressed XML resource");
+
+ promise_test(async (t) => {
+ const url = "/resource-timing/resources/foo.text.br";
+ const expectedDecodedSize = 10500;
+ const expectedEncodedSize = 15;
+
+ const timingPromise = waitForResourceTiming(url);
+ const response = await fetch(url);
+ await response.text();
+ const entry = await timingPromise;
+
+ assert_equals(entry.decodedBodySize, expectedDecodedSize,
+ "decodedBodySize should match the uncompressed brotli file size");
+ assert_equals(entry.encodedBodySize, expectedEncodedSize,
+ "encodedBodySize should match the compressed brotli file size");
+ }, "decodedBodySize for brotli-compressed text resource");
+
+ promise_test(async (t) => {
+ const url = "/resource-timing/resources/foo.text.gz";
+ const expectedDecodedSize = 10500;
+ const expectedEncodedSize = 57;
+
+ const timingPromise = waitForResourceTiming(url);
+ const response = await fetch(url);
+ await response.text();
+ const entry = await timingPromise;
+
+ assert_equals(entry.decodedBodySize, expectedDecodedSize,
+ "decodedBodySize should match the uncompressed gzip file size");
+ assert_equals(entry.encodedBodySize, expectedEncodedSize,
+ "encodedBodySize should match the compressed gzip file size");
+ }, "decodedBodySize for gzip-compressed text resource");
+
+ promise_test(async (t) => {
+ const url = "/resource-timing/resources/compressed-js.py?content_encoding=gzip";
+ const expectedDecodedSize = 53;
+
+ const timingPromise = waitForResourceTiming(url);
+ const response = await fetch(url);
+ await response.text();
+ const entry = await timingPromise;
+
+ assert_equals(entry.decodedBodySize, expectedDecodedSize,
+ "decodedBodySize should match the uncompressed JS file size");
+ assert_not_equals(entry.encodedBodySize, entry.decodedBodySize,
+ "encodedBodySize should differ from decodedBodySize for gzip-compressed JS");
+ assert_greater_than(entry.encodedBodySize, 0,
+ "encodedBodySize should be non-zero");
+ }, "decodedBodySize for dynamically gzip-compressed JS resource");
+
+ promise_test(async (t) => {
+ const url = "/resource-timing/resources/compressed-js.py?content_encoding=deflate";
+ const expectedDecodedSize = 53;
+
+ const timingPromise = waitForResourceTiming(url);
+ const response = await fetch(url);
+ await response.text();
+ const entry = await timingPromise;
+
+ assert_equals(entry.decodedBodySize, expectedDecodedSize,
+ "decodedBodySize should match the uncompressed JS file size");
+ assert_not_equals(entry.encodedBodySize, entry.decodedBodySize,
+ "encodedBodySize should differ from decodedBodySize for deflate-compressed JS");
+ assert_greater_than(entry.encodedBodySize, 0,
+ "encodedBodySize should be non-zero");
+ }, "decodedBodySize for deflate-compressed JS resource");
+
+ promise_test(async (t) => {
+ const url = "/resource-timing/resources/compressed-js.py?content_encoding=identity";
+ const expectedSize = 53;
+
+ const timingPromise = waitForResourceTiming(url);
+ const response = await fetch(url);
+ await response.text();
+ const entry = await timingPromise;
+
+ assert_equals(entry.decodedBodySize, expectedSize,
+ "decodedBodySize should match file size for uncompressed resource");
+ assert_equals(entry.encodedBodySize, expectedSize,
+ "encodedBodySize should equal decodedBodySize for uncompressed resource");
+ }, "decodedBodySize equals encodedBodySize for uncompressed resource");
+
+ compression_dictionary_promise_test(async (t) => {
+ const registerDictionaryUrl = '/fetch/compression-dictionary/resources/register-dictionary.py';
+ const compressedDataUrl = '/fetch/compression-dictionary/resources/compressed-data.py';
+
+ const dict = await (await fetch(registerDictionaryUrl)).text();
+ assert_equals(dict, kDefaultDictionaryContent);
+
+ await new Promise(resolve => t.step_timeout(resolve, 500));
+
+ const url = `${compressedDataUrl}?content_encoding=dcb`;
+ const expectedDecodedSize = 52;
+ const expectedEncodedSize = 75;
+
+ const timingPromise = waitForResourceTiming(url);
+ const response = await fetch(url);
+ const text = await response.text();
+ assert_equals(text, kExpectedCompressedData,
+ "The resource should decompress correctly");
+ const entry = await timingPromise;
+
+ assert_equals(entry.decodedBodySize, expectedDecodedSize,
+ "decodedBodySize should match the uncompressed data size (52 bytes)");
+ assert_equals(entry.encodedBodySize, expectedEncodedSize,
+ "encodedBodySize should match the dictionary-compressed brotli size (75 bytes including dictionary hash)");
+ }, "decodedBodySize for dictionary-compressed brotli (dcb) resource");
+
+ compression_dictionary_promise_test(async (t) => {
+ const registerDictionaryUrl = '/fetch/compression-dictionary/resources/register-dictionary.py';
+ const compressedDataUrl = '/fetch/compression-dictionary/resources/compressed-data.py';
+
+ const dict = await (await fetch(registerDictionaryUrl)).text();
+ assert_equals(dict, kDefaultDictionaryContent);
+
+ await new Promise(resolve => t.step_timeout(resolve, 500));
+
+ const url = `${compressedDataUrl}?content_encoding=dcz`;
+ const expectedDecodedSize = 52;
+ const expectedEncodedSize = 83;
+
+ const timingPromise = waitForResourceTiming(url);
+ const response = await fetch(url);
+ const text = await response.text();
+ assert_equals(text, kExpectedCompressedData,
+ "The resource should decompress correctly");
+ const entry = await timingPromise;
+
+ assert_equals(entry.decodedBodySize, expectedDecodedSize,
+ "decodedBodySize should match the uncompressed data size (52 bytes)");
+ assert_equals(entry.encodedBodySize, expectedEncodedSize,
+ "encodedBodySize should match the dictionary-compressed zstd size (83 bytes including dictionary hash)");
+ }, "decodedBodySize for dictionary-compressed zstd (dcz) resource");
+
+ </script>
+</head>
+<body>
+ <h1>Description</h1>
+ <p>
+ This test validates that PerformanceResourceTiming.decodedBodySize correctly reports
+ the size of resources after removing content encoding (gzip, brotli, deflate, and
+ compression dictionaries with dcb and dcz), and that it differs from encodedBodySize
+ for compressed resources.
+ </p>
+</body>
+</html>
