resourceloader: Add version to ResourceLoaderImage urls for long-cache

The code previously here did not work well as it merely forwarded the
hash from the current web request. This had numerous issues:

1. It was often null because requests for stylesheets do not cary
   a version hash.
2. When requested by JavaScript, the version hash would be a
   combination-hash of many unrelated modules, thus when requested as
   part of different batches, it would produce different urls which
   is not ideal.

The impact of this is minimal currently because we basically never use
these urls, as SVGs are almost always embedded instead of ref'ed by url.
PNG urls are only generated for non-JS modules and then only used in older
browsers not supporting SVG. And, even after all that, for the edge case
of an SVG being ref'ed by url, they would be stored in LocalStorage by
mw.loader with the name+version of the module the image belonged to, not
the version hash of the batch request it came with.

Which means that, yes, localstorage key for "somemodule+someversion" would
have different values for different users, based on which batch the value
came with, because the image urls were using the version hash of the batch
request from ResourceLoaderContext. This is weird, but didn't cause bugs
or inefficiencies because the user would never be exposed to the other
possible urls for that image because we always check LocalStorage first.
It did cause fragmentation server-side in Varnish, though.

This is all fixed now by always including a version, and setting it to
the version of the module. This means there is no more Varnish fragmentation
for these. And it means that browsers are now allowed to cache the images
served from these urls for 30+ days (immutable) instead of only 5min,
which is what happened when they didn't have a version parameter (or set to
null).

Bug: T233343
Change-Id: I4af7fda03698ed4c288d154e7787fb2f3cbbe6c5

diff --git a/includes/resourceloader/ResourceLoaderImage.php b/includes/resourceloader/ResourceLoaderImage.php
index 2b0f5ed..3878205 100644 (file)
--- a/includes/resourceloader/ResourceLoaderImage.php
+++ b/includes/resourceloader/ResourceLoaderImage.php
@@ -55,8 +55,9 @@ class ResourceLoaderImage {
        private $extension;
 
        /**
-        * @param string $name Image name
-        * @param string $module Module name
+        * @param string $name Self-name of the image as known to ResourceLoaderImageModule.
+        * @param string $module Self-name of the module containing this image.
+        *  Used to find the image in the registry e.g. through a load.php url.
         * @param string|array $descriptor Path to image file, or array structure containing paths
         * @param string $basePath Directory to which paths in descriptor refer
         * @param array $variants
@@ -217,7 +218,7 @@ class ResourceLoaderImage {
         * @param string $script URL to load.php
         * @param string|null $variant Variant to get the URL for
         * @param string $format Format to get the URL for, 'original' or 'rasterized'
-        * @return string
+        * @return string URL
         */
        public function getUrl( ResourceLoaderContext $context, $script, $variant, $format ) {
                $query = [
@@ -231,7 +232,8 @@ class ResourceLoaderImage {
                }
                // The following parameters are at the end to keep the original order of the parameters.
                $query['skin'] = $context->getSkin();
-               $query['version'] = $context->getVersion();
+               $rl = $context->getResourceLoader();
+               $query['version'] = $rl->makeVersionQuery( $context, [ $this->getModule() ] );
 
                return wfAppendQuery( $script, $query );
        }

diff --git a/includes/resourceloader/ResourceLoaderImageModule.php b/includes/resourceloader/ResourceLoaderImageModule.php
index 0585cfd..d46d26f 100644 (file)
--- a/includes/resourceloader/ResourceLoaderImageModule.php
+++ b/includes/resourceloader/ResourceLoaderImageModule.php
@@ -358,6 +358,10 @@ class ResourceLoaderImageModule extends ResourceLoaderModule {
        }
 
        /**
+        * This method must not be used by getDefinitionSummary as doing so would cause
+        * an infinite loop (we use ResourceLoaderImage::getUrl below which calls
+        * Module:getVersionHash, which calls Module::getDefinitionSummary).
+        *
         * @param ResourceLoaderContext $context
         * @param ResourceLoaderImage $image Image to get the style for
         * @param string $script URL to load.php

diff --git a/tests/phpunit/unit/includes/resourceloader/ResourceLoaderImageTest.php b/tests/phpunit/unit/includes/resourceloader/ResourceLoaderImageTest.php
index 5265b3e..02042b8 100644 (file)
--- a/tests/phpunit/unit/includes/resourceloader/ResourceLoaderImageTest.php
+++ b/tests/phpunit/unit/includes/resourceloader/ResourceLoaderImageTest.php
@@ -2,6 +2,7 @@
 
 /**
  * @group ResourceLoader
+ * @covers ResourceLoaderImage
  */
 class ResourceLoaderImageTest extends MediaWikiUnitTestCase {
 
@@ -53,7 +54,6 @@ class ResourceLoaderImageTest extends MediaWikiUnitTestCase {
        }
 
        /**
-        * @covers ResourceLoaderImage::getPath
         * @dataProvider provideGetPath
         */
        public function testGetPath( $imageName, $languageCode, $path ) {
@@ -84,10 +84,6 @@ class ResourceLoaderImageTest extends MediaWikiUnitTestCase {
                $this->assertEquals( $image->getPath( $context ), $this->imagesPath . '/' . $path );
        }
 
-       /**
-        * @covers ResourceLoaderImage::getExtension
-        * @covers ResourceLoaderImage::getMimeType
-        */
        public function testGetExtension() {
                $image = $this->getTestImage( 'def' );
                $this->assertEquals( $image->getExtension(), 'svg' );
@@ -99,11 +95,6 @@ class ResourceLoaderImageTest extends MediaWikiUnitTestCase {
                $this->assertEquals( $image->getExtension( 'rasterized' ), 'gif' );
        }
 
-       /**
-        * @covers ResourceLoaderImage::getImageData
-        * @covers ResourceLoaderImage::variantize
-        * @covers ResourceLoaderImage::massageSvgPathdata
-        */
        public function testGetImageData() {
                $context = $this->createMock( ResourceLoaderContext::class );
 
@@ -124,9 +115,6 @@ class ResourceLoaderImageTest extends MediaWikiUnitTestCase {
                $this->assertEquals( $image->getImageData( $context, null, 'rasterized' ), $data );
        }
 
-       /**
-        * @covers ResourceLoaderImage::massageSvgPathdata
-        */
        public function testMassageSvgPathdata() {
                $image = $this->getTestImage( 'ghi' );
                $data = file_get_contents( $this->imagesPath . '/ghi.svg' );