From 52b8a0db689c2df968776a1f369ea6a6db245d39 Mon Sep 17 00:00:00 2001 From: Tim Zallmann Date: Mon, 24 Jul 2017 17:36:52 +0000 Subject: [PATCH] Resolve "Lazy load images on the Frontend" --- app/assets/javascripts/copy_as_gfm.js | 10 ++- app/assets/javascripts/lazy_loader.js | 76 +++++++++++++++++++ app/assets/javascripts/main.js | 6 ++ app/assets/stylesheets/framework/avatar.scss | 2 + .../stylesheets/framework/typography.scss | 11 ++- .../stylesheets/framework/variables.scss | 4 +- app/helpers/avatars_helper.rb | 9 +-- app/helpers/emails_helper.rb | 4 +- app/helpers/lazy_image_tag_helper.rb | 24 ++++++ app/helpers/version_check_helper.rb | 2 +- app/models/concerns/cache_markdown_field.rb | 2 +- .../projects/blob/viewers/_image.html.haml | 2 +- .../projects/diffs/viewers/_image.html.haml | 14 ++-- ...34361-lazy-load-images-on-the-frontend.yml | 4 + doc/development/fe_guide/performance.md | 12 +++ features/steps/project/wiki.rb | 2 +- lib/banzai/filter/gollum_tags_filter.rb | 2 +- lib/banzai/filter/image_lazy_load_filter.rb | 16 ++++ lib/banzai/filter/image_link_filter.rb | 2 +- lib/banzai/filter/relative_link_filter.rb | 1 + lib/banzai/pipeline/gfm_pipeline.rb | 1 + spec/features/admin/admin_appearance_spec.rb | 4 +- spec/features/markdown_spec.rb | 2 +- .../user_uploads_avatar_to_group_spec.rb | 2 +- .../user_uploads_avatar_to_profile_spec.rb | 2 +- spec/helpers/application_helper_spec.rb | 7 +- spec/helpers/avatars_helper_spec.rb | 48 +++++------- spec/javascripts/lazy_loader_spec.js | 57 ++++++++++++++ .../banzai/filter/gollum_tags_filter_spec.rb | 4 +- .../filter/image_lazy_load_filter_spec.rb | 19 +++++ spec/support/matchers/markdown_matchers.rb | 4 +- 31 files changed, 287 insertions(+), 68 deletions(-) create mode 100644 app/assets/javascripts/lazy_loader.js create mode 100644 app/helpers/lazy_image_tag_helper.rb create mode 100644 changelogs/unreleased/34361-lazy-load-images-on-the-frontend.yml create mode 100644 lib/banzai/filter/image_lazy_load_filter.rb create mode 100644 spec/javascripts/lazy_loader_spec.js create mode 100644 spec/lib/banzai/filter/image_lazy_load_filter_spec.rb diff --git a/app/assets/javascripts/copy_as_gfm.js b/app/assets/javascripts/copy_as_gfm.js index ba9d9a3e1f7..54257531284 100644 --- a/app/assets/javascripts/copy_as_gfm.js +++ b/app/assets/javascripts/copy_as_gfm.js @@ -1,6 +1,7 @@ /* eslint-disable class-methods-use-this, object-shorthand, no-unused-vars, no-use-before-define, no-new, max-len, no-restricted-syntax, guard-for-in, no-continue */ import './lib/utils/common_utils'; +import { placeholderImage } from './lazy_loader'; const gfmRules = { // The filters referenced in lib/banzai/pipeline/gfm_pipeline.rb convert @@ -56,6 +57,11 @@ const gfmRules = { return text; }, }, + ImageLazyLoadFilter: { + 'img'(el, text) { + return `![${el.getAttribute('alt')}](${el.getAttribute('src')})`; + }, + }, VideoLinkFilter: { '.video-container'(el) { const videoEl = el.querySelector('video'); @@ -163,7 +169,9 @@ const gfmRules = { return text.trim().split('\n').map(s => `> ${s}`.trim()).join('\n'); }, 'img'(el) { - return `![${el.getAttribute('alt')}](${el.getAttribute('src')})`; + const imageSrc = el.src; + const imageUrl = imageSrc && imageSrc !== placeholderImage ? imageSrc : (el.dataset.src || ''); + return `![${el.getAttribute('alt')}](${imageUrl})`; }, 'a.anchor'(el, text) { // Don't render a Markdown link for the anchor link inside a heading diff --git a/app/assets/javascripts/lazy_loader.js b/app/assets/javascripts/lazy_loader.js new file mode 100644 index 00000000000..3d64b121fa7 --- /dev/null +++ b/app/assets/javascripts/lazy_loader.js @@ -0,0 +1,76 @@ +/* eslint-disable one-export, one-var, one-var-declaration-per-line */ + +import _ from 'underscore'; + +export const placeholderImage = 'data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw=='; +const SCROLL_THRESHOLD = 300; + +export default class LazyLoader { + constructor(options = {}) { + this.lazyImages = []; + this.observerNode = options.observerNode || '#content-body'; + + const throttledScrollCheck = _.throttle(() => this.scrollCheck(), 300); + const debouncedElementsInView = _.debounce(() => this.checkElementsInView(), 300); + + window.addEventListener('scroll', throttledScrollCheck); + window.addEventListener('resize', debouncedElementsInView); + + const scrollContainer = options.scrollContainer || window; + scrollContainer.addEventListener('load', () => this.loadCheck()); + } + searchLazyImages() { + this.lazyImages = [].slice.call(document.querySelectorAll('.lazy')); + this.checkElementsInView(); + } + startContentObserver() { + const contentNode = document.querySelector(this.observerNode) || document.querySelector('body'); + + if (contentNode) { + const observer = new MutationObserver(() => this.searchLazyImages()); + + observer.observe(contentNode, { + childList: true, + subtree: true, + }); + } + } + loadCheck() { + this.searchLazyImages(); + this.startContentObserver(); + } + scrollCheck() { + requestAnimationFrame(() => this.checkElementsInView()); + } + checkElementsInView() { + const scrollTop = pageYOffset; + const visHeight = scrollTop + innerHeight + SCROLL_THRESHOLD; + let imgBoundRect, imgTop, imgBound; + + // Loading Images which are in the current viewport or close to them + this.lazyImages = this.lazyImages.filter((selectedImage) => { + if (selectedImage.getAttribute('data-src')) { + imgBoundRect = selectedImage.getBoundingClientRect(); + + imgTop = scrollTop + imgBoundRect.top; + imgBound = imgTop + imgBoundRect.height; + + if (scrollTop < imgBound && visHeight > imgTop) { + LazyLoader.loadImage(selectedImage); + return false; + } + + return true; + } + return false; + }); + } + static loadImage(img) { + if (img.getAttribute('data-src')) { + img.setAttribute('src', img.getAttribute('data-src')); + img.removeAttribute('data-src'); + img.classList.remove('lazy'); + img.classList.add('js-lazy-loaded'); + } + } +} diff --git a/app/assets/javascripts/main.js b/app/assets/javascripts/main.js index 26c67fb721c..44b502cdab3 100644 --- a/app/assets/javascripts/main.js +++ b/app/assets/javascripts/main.js @@ -109,6 +109,7 @@ import './label_manager'; import './labels'; import './labels_select'; import './layout_nav'; +import LazyLoader from './lazy_loader'; import './line_highlighter'; import './logo'; import './member_expiration_date'; @@ -166,6 +167,11 @@ window.addEventListener('load', function onLoad() { gl.utils.handleLocationHash(); }, false); +gl.lazyLoader = new LazyLoader({ + scrollContainer: window, + observerNode: '#content-body' +}); + $(function () { var $body = $('body'); var $document = $(document); diff --git a/app/assets/stylesheets/framework/avatar.scss b/app/assets/stylesheets/framework/avatar.scss index 06f7af33f94..0dfa7a31d31 100644 --- a/app/assets/stylesheets/framework/avatar.scss +++ b/app/assets/stylesheets/framework/avatar.scss @@ -35,6 +35,8 @@ width: 40px; height: 40px; padding: 0; + background: $avatar-background; + overflow: hidden; &.avatar-inline { float: none; diff --git a/app/assets/stylesheets/framework/typography.scss b/app/assets/stylesheets/framework/typography.scss index 8a58c1ed567..befd8133be0 100644 --- a/app/assets/stylesheets/framework/typography.scss +++ b/app/assets/stylesheets/framework/typography.scss @@ -11,8 +11,17 @@ } img { - max-width: 100%; + /*max-width: 100%;*/ margin: 0 0 8px; + min-width: 200px; + min-height: 100px; + background-color: $gray-lightest; + } + + img.js-lazy-loaded { + min-width: none; + min-height: none; + background-color: none; } p a:not(.no-attachment-icon) img { diff --git a/app/assets/stylesheets/framework/variables.scss b/app/assets/stylesheets/framework/variables.scss index 7016208f624..cf0a1ad57d0 100644 --- a/app/assets/stylesheets/framework/variables.scss +++ b/app/assets/stylesheets/framework/variables.scss @@ -379,7 +379,9 @@ $issue-boards-card-shadow: rgba(186, 186, 186, 0.5); * Avatar */ $avatar_radius: 50%; -$avatar-border: $border-color; +$avatar-border: $gray-normal; +$avatar-border-hover: $gray-darker; +$avatar-background: $gray-lightest; $gl-avatar-size: 40px; /* diff --git a/app/helpers/avatars_helper.rb b/app/helpers/avatars_helper.rb index bbe7f3c8fb4..0e068d4b51c 100644 --- a/app/helpers/avatars_helper.rb +++ b/app/helpers/avatars_helper.rb @@ -11,17 +11,12 @@ module AvatarsHelper def user_avatar_without_link(options = {}) avatar_size = options[:size] || 16 user_name = options[:user].try(:name) || options[:user_name] - css_class = options[:css_class] || '' avatar_url = options[:url] || avatar_icon(options[:user] || options[:user_email], avatar_size) data_attributes = { container: 'body' } - if options[:lazy] - data_attributes[:src] = avatar_url - end - image_tag( - options[:lazy] ? '' : avatar_url, - class: "avatar has-tooltip s#{avatar_size} #{css_class}", + avatar_url, + class: %W[avatar has-tooltip s#{avatar_size}].push(*options[:css_class]), alt: "#{user_name}'s avatar", title: user_name, data: data_attributes diff --git a/app/helpers/emails_helper.rb b/app/helpers/emails_helper.rb index fdbca789d21..5f11fe62030 100644 --- a/app/helpers/emails_helper.rb +++ b/app/helpers/emails_helper.rb @@ -61,8 +61,8 @@ module EmailsHelper else image_tag( image_url('mailers/gitlab_header_logo.gif'), - size: "55x50", - alt: "GitLab" + size: '55x50', + alt: 'GitLab' ) end end diff --git a/app/helpers/lazy_image_tag_helper.rb b/app/helpers/lazy_image_tag_helper.rb new file mode 100644 index 00000000000..2c5619ac41b --- /dev/null +++ b/app/helpers/lazy_image_tag_helper.rb @@ -0,0 +1,24 @@ +module LazyImageTagHelper + def placeholder_image + "data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==" + end + + # Override the default ActionView `image_tag` helper to support lazy-loading + def image_tag(source, options = {}) + options = options.symbolize_keys + + unless options.delete(:lazy) == false + options[:data] ||= {} + options[:data][:src] = path_to_image(source) + options[:class] ||= "" + options[:class] << " lazy" + + source = placeholder_image + end + + super(source, options) + end + + # Required for Banzai::Filter::ImageLazyLoadFilter + module_function :placeholder_image +end diff --git a/app/helpers/version_check_helper.rb b/app/helpers/version_check_helper.rb index 456598b4c28..3b175251446 100644 --- a/app/helpers/version_check_helper.rb +++ b/app/helpers/version_check_helper.rb @@ -2,7 +2,7 @@ module VersionCheckHelper def version_status_badge if Rails.env.production? && current_application_settings.version_check_enabled image_url = VersionCheck.new.url - image_tag image_url, class: 'js-version-status-badge' + image_tag image_url, class: 'js-version-status-badge', lazy: false end end end diff --git a/app/models/concerns/cache_markdown_field.rb b/app/models/concerns/cache_markdown_field.rb index 95152dcd68c..48547a938fc 100644 --- a/app/models/concerns/cache_markdown_field.rb +++ b/app/models/concerns/cache_markdown_field.rb @@ -11,7 +11,7 @@ module CacheMarkdownField extend ActiveSupport::Concern # Increment this number every time the renderer changes its output - CACHE_VERSION = 1 + CACHE_VERSION = 2 # changes to these attributes cause the cache to be invalidates INVALIDATED_BY = %w[author project].freeze diff --git a/app/views/projects/blob/viewers/_image.html.haml b/app/views/projects/blob/viewers/_image.html.haml index 640d59b3174..1650aa8197f 100644 --- a/app/views/projects/blob/viewers/_image.html.haml +++ b/app/views/projects/blob/viewers/_image.html.haml @@ -1,2 +1,2 @@ .file-content.image_file - %img{ src: blob_raw_url, alt: viewer.blob.name } + %img{ 'data-src': blob_raw_url, alt: viewer.blob.name } diff --git a/app/views/projects/diffs/viewers/_image.html.haml b/app/views/projects/diffs/viewers/_image.html.haml index 33d3dcbeafa..05877ceed3d 100644 --- a/app/views/projects/diffs/viewers/_image.html.haml +++ b/app/views/projects/diffs/viewers/_image.html.haml @@ -8,7 +8,7 @@ .image %span.wrap .frame{ class: (diff_file.deleted_file? ? 'deleted' : 'added') } - %img{ src: blob_raw_path, alt: diff_file.file_path } + %img{ 'data-src': blob_raw_path, alt: diff_file.file_path } %p.image-info= number_to_human_size(blob.size) - else .image @@ -16,7 +16,7 @@ %span.wrap .frame.deleted %a{ href: project_blob_path(@project, tree_join(diff_file.old_content_sha, diff_file.old_path)) } - %img{ src: old_blob_raw_path, alt: diff_file.old_path } + %img{ 'data-src': old_blob_raw_path, alt: diff_file.old_path } %p.image-info.hide %span.meta-filesize= number_to_human_size(old_blob.size) | @@ -28,7 +28,7 @@ %span.wrap .frame.added %a{ href: project_blob_path(@project, tree_join(diff_file.content_sha, diff_file.new_path)) } - %img{ src: blob_raw_path, alt: diff_file.new_path } + %img{ 'data-src': blob_raw_path, alt: diff_file.new_path } %p.image-info.hide %span.meta-filesize= number_to_human_size(blob.size) | @@ -41,10 +41,10 @@ .swipe.view.hide .swipe-frame .frame.deleted - %img{ src: old_blob_raw_path, alt: diff_file.old_path } + %img{ 'data-src': old_blob_raw_path, alt: diff_file.old_path } .swipe-wrap .frame.added - %img{ src: blob_raw_path, alt: diff_file.new_path } + %img{ 'data-src': blob_raw_path, alt: diff_file.new_path } %span.swipe-bar %span.top-handle %span.bottom-handle @@ -52,9 +52,9 @@ .onion-skin.view.hide .onion-skin-frame .frame.deleted - %img{ src: old_blob_raw_path, alt: diff_file.old_path } + %img{ 'data-src': old_blob_raw_path, alt: diff_file.old_path } .frame.added - %img{ src: blob_raw_path, alt: diff_file.new_path } + %img{ 'data-src': blob_raw_path, alt: diff_file.new_path } .controls .transparent .drag-track diff --git a/changelogs/unreleased/34361-lazy-load-images-on-the-frontend.yml b/changelogs/unreleased/34361-lazy-load-images-on-the-frontend.yml new file mode 100644 index 00000000000..d188a558d38 --- /dev/null +++ b/changelogs/unreleased/34361-lazy-load-images-on-the-frontend.yml @@ -0,0 +1,4 @@ +--- +title: Lazy load images for better Frontend performance +merge_request: 12503 +author: diff --git a/doc/development/fe_guide/performance.md b/doc/development/fe_guide/performance.md index 2ddcbe13afa..f25313d6cff 100644 --- a/doc/development/fe_guide/performance.md +++ b/doc/development/fe_guide/performance.md @@ -23,6 +23,18 @@ controlled by the server. 1. The backend code will most likely be using etags. You do not and should not check for status `304 Not Modified`. The browser will transform it for you. +### Lazy Loading + +To improve the time to first render we are using lazy loading for images. This works by setting +the actual image source on the `data-src` attribute. After the HTML is rendered and JavaScript is loaded, +the value of `data-src` will be moved to `src` automatically if the image is in the current viewport. + +* Prepare images in HTML for lazy loading by renaming the `src` attribute to `data-src` +* If you are using the Rails `image_tag` helper, all images will be lazy-loaded by default unless `lazy: false` is provided. + +If you are asynchronously adding content which contains lazy images then you need to call the function +`gl.lazyLoader.searchLazyImages()` which will search for lazy images and load them if needed. + ## Reducing Asset Footprint ### Page-specific JavaScript diff --git a/features/steps/project/wiki.rb b/features/steps/project/wiki.rb index a2f5d2e1515..9d38939378d 100644 --- a/features/steps/project/wiki.rb +++ b/features/steps/project/wiki.rb @@ -114,7 +114,7 @@ class Spinach::Features::ProjectWiki < Spinach::FeatureSteps end step 'Image should be shown on the page' do - expect(page).to have_xpath("//img[@src=\"image.jpg\"]") + expect(page).to have_xpath("//img[@data-src=\"image.jpg\"]") end step 'I click on image link' do diff --git a/lib/banzai/filter/gollum_tags_filter.rb b/lib/banzai/filter/gollum_tags_filter.rb index 0ea4eeaed5b..2e259904673 100644 --- a/lib/banzai/filter/gollum_tags_filter.rb +++ b/lib/banzai/filter/gollum_tags_filter.rb @@ -118,7 +118,7 @@ module Banzai end if path - content_tag(:img, nil, src: path, class: 'gfm') + content_tag(:img, nil, data: { src: path }, class: 'gfm') end end diff --git a/lib/banzai/filter/image_lazy_load_filter.rb b/lib/banzai/filter/image_lazy_load_filter.rb new file mode 100644 index 00000000000..7a81d583b82 --- /dev/null +++ b/lib/banzai/filter/image_lazy_load_filter.rb @@ -0,0 +1,16 @@ +module Banzai + module Filter + # HTML filter that moves the value of the src attribute to the data-src attribute so it can be lazy loaded + class ImageLazyLoadFilter < HTML::Pipeline::Filter + def call + doc.xpath('descendant-or-self::img').each do |img| + img['class'] ||= '' << 'lazy' + img['data-src'] = img['src'] + img['src'] = LazyImageTagHelper.placeholder_image + end + + doc + end + end + end +end diff --git a/lib/banzai/filter/image_link_filter.rb b/lib/banzai/filter/image_link_filter.rb index 123c92fd250..f318c425962 100644 --- a/lib/banzai/filter/image_link_filter.rb +++ b/lib/banzai/filter/image_link_filter.rb @@ -10,7 +10,7 @@ module Banzai link = doc.document.create_element( 'a', class: 'no-attachment-icon', - href: img['src'], + href: img['data-src'] || img['src'], target: '_blank', rel: 'noopener noreferrer' ) diff --git a/lib/banzai/filter/relative_link_filter.rb b/lib/banzai/filter/relative_link_filter.rb index 9e23c8f8c55..c2fed57a0d8 100644 --- a/lib/banzai/filter/relative_link_filter.rb +++ b/lib/banzai/filter/relative_link_filter.rb @@ -22,6 +22,7 @@ module Banzai doc.css('img, video').each do |el| process_link_attr el.attribute('src') + process_link_attr el.attribute('data-src') end doc diff --git a/lib/banzai/pipeline/gfm_pipeline.rb b/lib/banzai/pipeline/gfm_pipeline.rb index bd4d1aa9ff8..3208abfc538 100644 --- a/lib/banzai/pipeline/gfm_pipeline.rb +++ b/lib/banzai/pipeline/gfm_pipeline.rb @@ -16,6 +16,7 @@ module Banzai Filter::MathFilter, Filter::UploadLinkFilter, Filter::VideoLinkFilter, + Filter::ImageLazyLoadFilter, Filter::ImageLinkFilter, Filter::EmojiFilter, Filter::TableOfContentsFilter, diff --git a/spec/features/admin/admin_appearance_spec.rb b/spec/features/admin/admin_appearance_spec.rb index b9e361328df..2f90f668e89 100644 --- a/spec/features/admin/admin_appearance_spec.rb +++ b/spec/features/admin/admin_appearance_spec.rb @@ -63,11 +63,11 @@ feature 'Admin Appearance', feature: true do end def logo_selector - '//img[@src^="/uploads/-/system/appearance/logo"]' + '//img[data-src^="/uploads/-/system/appearance/logo"]' end def header_logo_selector - '//img[@src^="/uploads/-/system/appearance/header_logo"]' + '//img[data-src^="/uploads/-/system/appearance/header_logo"]' end def logo_fixture diff --git a/spec/features/markdown_spec.rb b/spec/features/markdown_spec.rb index 534be3ab5a7..1aca3e3a9fd 100644 --- a/spec/features/markdown_spec.rb +++ b/spec/features/markdown_spec.rb @@ -100,7 +100,7 @@ describe 'GitLab Markdown', feature: true do end it 'permits img elements' do - expect(doc).to have_selector('img[src*="smile.png"]') + expect(doc).to have_selector('img[data-src*="smile.png"]') end it 'permits br elements' do diff --git a/spec/features/uploads/user_uploads_avatar_to_group_spec.rb b/spec/features/uploads/user_uploads_avatar_to_group_spec.rb index 5843f18d89f..8188d4c79f4 100644 --- a/spec/features/uploads/user_uploads_avatar_to_group_spec.rb +++ b/spec/features/uploads/user_uploads_avatar_to_group_spec.rb @@ -18,7 +18,7 @@ feature 'User uploads avatar to group', feature: true do visit group_path(group) - expect(page).to have_selector(%Q(img[src$="/uploads/-/system/group/avatar/#{group.id}/dk.png"])) + expect(page).to have_selector(%Q(img[data-src$="/uploads/-/system/group/avatar/#{group.id}/dk.png"])) # Cheating here to verify something that isn't user-facing, but is important expect(group.reload.avatar.file).to exist diff --git a/spec/features/uploads/user_uploads_avatar_to_profile_spec.rb b/spec/features/uploads/user_uploads_avatar_to_profile_spec.rb index e8171dcaeb0..2628508afe8 100644 --- a/spec/features/uploads/user_uploads_avatar_to_profile_spec.rb +++ b/spec/features/uploads/user_uploads_avatar_to_profile_spec.rb @@ -16,7 +16,7 @@ feature 'User uploads avatar to profile', feature: true do visit user_path(user) - expect(page).to have_selector(%Q(img[src$="/uploads/-/system/user/avatar/#{user.id}/dk.png"])) + expect(page).to have_selector(%Q(img[data-src$="/uploads/-/system/user/avatar/#{user.id}/dk.png"])) # Cheating here to verify something that isn't user-facing, but is important expect(user.reload.avatar.file).to exist diff --git a/spec/helpers/application_helper_spec.rb b/spec/helpers/application_helper_spec.rb index f5e139685e8..ac5a58ac189 100644 --- a/spec/helpers/application_helper_spec.rb +++ b/spec/helpers/application_helper_spec.rb @@ -62,13 +62,13 @@ describe ApplicationHelper do avatar_url = "/uploads/-/system/project/avatar/#{project.id}/banana_sample.gif" expect(helper.project_icon(project.full_path).to_s) - .to eq "\"Banana" + .to eq "" allow(ActionController::Base).to receive(:asset_host).and_return(gitlab_host) avatar_url = "#{gitlab_host}/uploads/-/system/project/avatar/#{project.id}/banana_sample.gif" expect(helper.project_icon(project.full_path).to_s) - .to eq "\"Banana" + .to eq "" end it 'gives uploaded icon when present' do @@ -77,7 +77,8 @@ describe ApplicationHelper do allow_any_instance_of(Project).to receive(:avatar_in_git).and_return(true) avatar_url = "#{gitlab_host}#{project_avatar_path(project)}" - expect(helper.project_icon(project.full_path).to_s).to match(image_tag(avatar_url)) + expect(helper.project_icon(project.full_path).to_s) + .to eq "" end end diff --git a/spec/helpers/avatars_helper_spec.rb b/spec/helpers/avatars_helper_spec.rb index 049475a5408..d16fcf21e45 100644 --- a/spec/helpers/avatars_helper_spec.rb +++ b/spec/helpers/avatars_helper_spec.rb @@ -27,11 +27,11 @@ describe AvatarsHelper do it 'displays user avatar' do is_expected.to eq image_tag( - avatar_icon(user, 16), - class: 'avatar has-tooltip s16 ', + LazyImageTagHelper.placeholder_image, + class: 'avatar has-tooltip s16 lazy', alt: "#{user.name}'s avatar", title: user.name, - data: { container: 'body' } + data: { container: 'body', src: avatar_icon(user, 16) } ) end @@ -40,22 +40,8 @@ describe AvatarsHelper do it 'uses provided css_class' do is_expected.to eq image_tag( - avatar_icon(user, 16), - class: "avatar has-tooltip s16 #{options[:css_class]}", - alt: "#{user.name}'s avatar", - title: user.name, - data: { container: 'body' } - ) - end - end - - context 'with lazy parameter' do - let(:options) { { user: user, lazy: true } } - - it 'uses data-src instead of src' do - is_expected.to eq image_tag( - '', - class: 'avatar has-tooltip s16 ', + LazyImageTagHelper.placeholder_image, + class: "avatar has-tooltip s16 #{options[:css_class]} lazy", alt: "#{user.name}'s avatar", title: user.name, data: { container: 'body', src: avatar_icon(user, 16) } @@ -68,11 +54,11 @@ describe AvatarsHelper do it 'uses provided size' do is_expected.to eq image_tag( - avatar_icon(user, options[:size]), - class: "avatar has-tooltip s#{options[:size]} ", + LazyImageTagHelper.placeholder_image, + class: "avatar has-tooltip s#{options[:size]} lazy", alt: "#{user.name}'s avatar", title: user.name, - data: { container: 'body' } + data: { container: 'body', src: avatar_icon(user, options[:size]) } ) end end @@ -82,11 +68,11 @@ describe AvatarsHelper do it 'uses provided url' do is_expected.to eq image_tag( - options[:url], - class: 'avatar has-tooltip s16 ', + LazyImageTagHelper.placeholder_image, + class: 'avatar has-tooltip s16 lazy', alt: "#{user.name}'s avatar", title: user.name, - data: { container: 'body' } + data: { container: 'body', src: options[:url] } ) end end @@ -99,22 +85,22 @@ describe AvatarsHelper do it 'prefers user parameter' do is_expected.to eq image_tag( - avatar_icon(user, 16), - class: 'avatar has-tooltip s16 ', + LazyImageTagHelper.placeholder_image, + class: 'avatar has-tooltip s16 lazy', alt: "#{user.name}'s avatar", title: user.name, - data: { container: 'body' } + data: { container: 'body', src: avatar_icon(user, 16) } ) end end it 'uses user_name and user_email parameter if user is not present' do is_expected.to eq image_tag( - avatar_icon(options[:user_email], 16), - class: 'avatar has-tooltip s16 ', + LazyImageTagHelper.placeholder_image, + class: 'avatar has-tooltip s16 lazy', alt: "#{options[:user_name]}'s avatar", title: options[:user_name], - data: { container: 'body' } + data: { container: 'body', src: avatar_icon(options[:user_email], 16) } ) end end diff --git a/spec/javascripts/lazy_loader_spec.js b/spec/javascripts/lazy_loader_spec.js new file mode 100644 index 00000000000..1d81e4e2d1a --- /dev/null +++ b/spec/javascripts/lazy_loader_spec.js @@ -0,0 +1,57 @@ +import LazyLoader from '~/lazy_loader'; + +let lazyLoader = null; + +describe('LazyLoader', function () { + preloadFixtures('issues/issue_with_comment.html.raw'); + + beforeEach(function () { + loadFixtures('issues/issue_with_comment.html.raw'); + lazyLoader = new LazyLoader({ + observerNode: 'body', + }); + // Doing everything that happens normally in onload + lazyLoader.loadCheck(); + }); + describe('behavior', function () { + it('should copy value from data-src to src for img 1', function (done) { + const img = document.querySelectorAll('img[data-src]')[0]; + const originalDataSrc = img.getAttribute('data-src'); + img.scrollIntoView(); + + setTimeout(() => { + expect(img.getAttribute('src')).toBe(originalDataSrc); + expect(document.getElementsByClassName('js-lazy-loaded').length).toBeGreaterThan(0); + done(); + }, 100); + }); + + it('should lazy load dynamically added data-src images', function (done) { + const newImg = document.createElement('img'); + const testPath = '/img/testimg.png'; + newImg.className = 'lazy'; + newImg.setAttribute('data-src', testPath); + document.body.appendChild(newImg); + newImg.scrollIntoView(); + + setTimeout(() => { + expect(newImg.getAttribute('src')).toBe(testPath); + expect(document.getElementsByClassName('js-lazy-loaded').length).toBeGreaterThan(0); + done(); + }, 100); + }); + + it('should not alter normal images', function (done) { + const newImg = document.createElement('img'); + const testPath = '/img/testimg.png'; + newImg.setAttribute('src', testPath); + document.body.appendChild(newImg); + newImg.scrollIntoView(); + + setTimeout(() => { + expect(newImg).not.toHaveClass('js-lazy-loaded'); + done(); + }, 100); + }); + }); +}); diff --git a/spec/lib/banzai/filter/gollum_tags_filter_spec.rb b/spec/lib/banzai/filter/gollum_tags_filter_spec.rb index 082c0d4dd0d..cbb2808c6bb 100644 --- a/spec/lib/banzai/filter/gollum_tags_filter_spec.rb +++ b/spec/lib/banzai/filter/gollum_tags_filter_spec.rb @@ -22,7 +22,7 @@ describe Banzai::Filter::GollumTagsFilter, lib: true do tag = '[[images/image.jpg]]' doc = filter("See #{tag}", project_wiki: project_wiki) - expect(doc.at_css('img')['src']).to eq "#{project_wiki.wiki_base_path}/images/image.jpg" + expect(doc.at_css('img')['data-src']).to eq "#{project_wiki.wiki_base_path}/images/image.jpg" end it 'does not creates img tag if image does not exist' do @@ -40,7 +40,7 @@ describe Banzai::Filter::GollumTagsFilter, lib: true do tag = '[[http://example.com/image.jpg]]' doc = filter("See #{tag}", project_wiki: project_wiki) - expect(doc.at_css('img')['src']).to eq "http://example.com/image.jpg" + expect(doc.at_css('img')['data-src']).to eq "http://example.com/image.jpg" end it 'does not creates img tag for invalid URL' do diff --git a/spec/lib/banzai/filter/image_lazy_load_filter_spec.rb b/spec/lib/banzai/filter/image_lazy_load_filter_spec.rb new file mode 100644 index 00000000000..c19de7b784a --- /dev/null +++ b/spec/lib/banzai/filter/image_lazy_load_filter_spec.rb @@ -0,0 +1,19 @@ +require 'spec_helper' + +describe Banzai::Filter::ImageLazyLoadFilter, lib: true do + include FilterSpecHelper + + def image(path) + %() + end + + it 'transforms the image src to a data-src' do + doc = filter(image('/uploads/e90decf88d8f96fe9e1389afc2e4a91f/test.jpg')) + expect(doc.at_css('img')['data-src']).to eq '/uploads/e90decf88d8f96fe9e1389afc2e4a91f/test.jpg' + end + + it 'works with external images' do + doc = filter(image('https://i.imgur.com/DfssX9C.jpg')) + expect(doc.at_css('img')['data-src']).to eq 'https://i.imgur.com/DfssX9C.jpg' + end +end diff --git a/spec/support/matchers/markdown_matchers.rb b/spec/support/matchers/markdown_matchers.rb index bbbbaf4c5e8..7afa57fb76b 100644 --- a/spec/support/matchers/markdown_matchers.rb +++ b/spec/support/matchers/markdown_matchers.rb @@ -17,7 +17,7 @@ module MarkdownMatchers image = actual.at_css('img[alt="Relative Image"]') expect(link['href']).to end_with('master/doc/README.md') - expect(image['src']).to end_with('master/app/assets/images/touch-icon-ipad.png') + expect(image['data-src']).to end_with('master/app/assets/images/touch-icon-ipad.png') end end @@ -70,7 +70,7 @@ module MarkdownMatchers # GollumTagsFilter matcher :parse_gollum_tags do def have_image(src) - have_css("img[src$='#{src}']") + have_css("img[data-src$='#{src}']") end prefix = '/namespace1/gitlabhq/wikis'