Google je predstavio novi alat koji omogućava testiranje i daje preporuke za unapređenje performansi, SEO optimizacije, bezbednosti, primene najboljih praksi i pristupačnosti web stranica.
Nedavno je Google lansirao Lighthouse, alat otvorenog koda koji služi za ručnu i automatizovanu reviziju web lokacija.
Koje metrike testira Google Lighthouse?
Sistem testira više od 75 različitih metrika i daje ukupnu ocenu. Za vlasnike sajtova, SEO analitičare i webmastere, neke od najvažnijih metrika su:
- Performanse – vreme do interaktivnosti, kašnjenje, indeks brzine, optimizacija resursa, TTFB, isporuka sadržaja, vreme izvršavanja skripti, veličina DOM-a, itd.
- SEO – prilagođenost mobilnim uređajima, meta podaci, indeksiranje, kanonski URL-ovi, struktura, itd.
- Najbolje prakse – optimizacija slika, JS biblioteke, prijavljivanje grešaka u pregledaču, dostupnost putem HTTPS-a, poznate JS ranjivosti, itd.
- Pristupačnost – elementi stranice, jezik, ARIA atributi, itd.
- PWA (progresivna web aplikacija) – preusmeravanje HTTP na HTTPS, ispravan kod odgovora, brzo učitavanje na 3G mreži, početni ekran, viewport, itd.
Ovaj alat je izuzetno koristan i može se upotrebljavati na različite načine.
Programeri mogu koristiti Node.js za pokretanje testova programski. Na tržištu već postoji nekoliko alata koji koriste Lighthouse za kontinuirano praćenje performansi sajtova.
Saznajmo kako se izvodi testiranje pomoću Lighthouse-a na vašoj web lokaciji.
Počnimo sa najjednostavnijom metodom.
Merenje pomoću web.dev
Google je pre nekoliko meseci objavio web.dev, koji je brzo stekao popularnost. Online testiranje je veoma jednostavno.
Posetite stranicu za merenje i unesite URL web stranice koju želite analizirati. Nakon nekoliko sekundi, pojaviće se detaljan izveštaj sa ukupnim rezultatom.
Rezultati pokazuju i metrike uspeha za obavljene revizije, kao i stavke na koje treba obratiti posebnu pažnju.
Ne fokusirajte se previše na postizanje maksimalnog rezultata. Čak i Google-ovi sajtovi ne ostvaruju savršen rezultat.
Ove rezultate treba smatrati smernicama i potruditi se da unapredite sajt koliko god je to moguće.
Napomena: web.dev emulira testiranje na mobilnom uređaju i trenutno ne postoji opcija za testiranje na desktop računarima.
Chrome
Da li ste znali da je Lighthouse dostupan u vašem Chrome pretraživaču? Odlična vest je da možete birati da li ćete testirati mobilnu ili desktop verziju sajta, a opcija se nalazi u alatkama za programere.
- Otvorite Chrome pretraživač
- Pristupite web lokaciji koju želite testirati
- Otvorite alatke za programere (pritisnite F12 na Windows-u) ili kliknite desnim tasterom miša na stranicu i odaberite „Inspect“.
- Idite na karticu „Audits“.
Kao što vidite, imate opciju da izaberete koje metrike želite da testirate. Ovo je korisno ako želite da se fokusirate na određeni cilj i brže dobijete rezultate.
Izgled i osećaj rezultata su slični onima sa web.dev.
Međutim, ako bolje pogledate, ovde postoji još jedna grupa metrika – progresivna web aplikacija. To je još jedan razlog da koristite Chrome za reviziju.
Geekflare Lighthouse API
Podatke o performansama sajta možete dobiti i putem Geekflare Lighthouse API-ja. On izdvaja Lighthouse metrike za mobilne ili desktop uređaje jednim klikom u HTML, JSON ili CSV formatu.
Izveštaj možete prilagoditi promenom izlaznog formata i/ili fokusiranjem na određenu metriku, poput SEO optimizacije.
{
"parameters": [
"--output=html",
"--only-categories=seo",
],
"url": "example.com"
}
Postoji besplatna verzija koja omogućava 3000 API poziva mesečno. Plaćene verzije nude podršku za više lokacija, rezidencijalne proksi servere i veću brzinu zahteva, po ceni od samo 5 dolara mesečno.
Node.js
Lighthouse je dostupan i kao Node modul. Možete ga instalirati na server i koristiti programski ili putem komandne linije. Pogledajmo kako instalirati Lighthouse i pokrenuti testove.
Instaliranje Lighthouse-a na Ubuntu 18.x
Testiranje je vršeno na DigitalOcean serveru. Lighthouse zahteva Node LTS 8.9 ili noviji, pretpostavljamo da ga već imate instaliranog. Ako ne, pogledajte ovaj vodič za instalaciju Node.js.
Biće vam potreban i Chromium pretraživač instaliran na serveru. Uputstva za instalaciju su navedena ovde.
Instalacija Lighthouse-a je jednostavna, kao i kod drugih modula.
- Prijavite se na svoj server.
- Pokrenite sledeću komandu za instalaciju:
npm install -g lighthouse
Koristi se -g da se instalira kao globalni modul.
[email protected]:~# npm install -g lighthouse /usr/bin/lighthouse -> /usr/lib/node_modules/lighthouse/lighthouse-cli/index.js /usr/bin/chrome-debug -> /usr/lib/node_modules/lighthouse/lighthouse-core/scripts/manual-chrome-launcher.js > [email protected] postinstall /usr/lib/node_modules/lighthouse/node_modules/axe-core > node build/utils/postinstall.js + [email protected] added 179 packages from 119 contributors in 10.094s [email protected]:~#
Nakon instalacije, pokrenite Lighthouse komandu da biste bili sigurni da je pravilno instaliran.
[email protected]:~# lighthouse Please provide a url Specify --help for available options [email protected]:~#
Lighthouse je spreman za reviziju. Isprobajmo neke opcije testiranja.
Za pokretanje testa sa pretraživačem bez glave:
lighthouse URL --chrome-flags="--headless"
Morate uneti apsolutni URL, uključujući HTTP ili HTTPS.
Primer:
[email protected]:~$ lighthouse https://techblog.co.rs.com --chrome-flags="--headless" ChromeLauncher Waiting for browser. +0ms ChromeLauncher Waiting for browser... +1ms ChromeLauncher Waiting for browser..... +511ms ChromeLauncher Waiting for browser.....✓ +2ms status Connecting to browser +176ms status Resetting state with <a href="https://techblog.co.rs.com/aboutblank-in-chrome-firefox-safari/">about:blank</a> +24ms status Benchmarking machine +30ms status Initializing… +508ms status Loading page & waiting for onload Scripts, CSSUsage, Viewport, ViewportDimensions, ThemeColor, Manifest, RuntimeExceptions, ChromeConsoleMessages, ImageUsage, Accessibility, LinkElements, AnchorsWithNoRelNoopener, AppCacheManifest, Doctype, DOMStats, JSLibraries, OptimizedImages, PasswordInputsWithPreventedPaste, ResponseCompression, TagsBlockingFirstPaint, MetaDescription, FontSize, CrawlableLinks, MetaRobots, Hreflang, EmbeddedContent, Canonical, RobotsTxt +27ms status Retrieving in-page: Scripts +2s status Retrieving in-page: CSSUsage +0ms status Retrieving in-page: Viewport +0ms status Retrieving in-page: ViewportDimensions +0ms status Retrieving in-page: ThemeColor +0ms status Retrieving in-page: Manifest +0ms status Retrieving in-page: RuntimeExceptions +0ms status Retrieving in-page: ChromeConsoleMessages +0ms status Retrieving in-page: ImageUsage +0ms status Retrieving in-page: Accessibility +0ms status Retrieving in-page: LinkElements +0ms status Retrieving in-page: AnchorsWithNoRelNoopener +1ms status Retrieving in-page: AppCacheManifest +0ms status Retrieving in-page: Doctype +0ms status Retrieving in-page: DOMStats +0ms status Retrieving in-page: JSLibraries +0ms status Retrieving in-page: OptimizedImages +0ms status Retrieving in-page: PasswordInputsWithPreventedPaste +0ms status Retrieving in-page: ResponseCompression +0ms status Retrieving in-page: TagsBlockingFirstPaint +0ms status Retrieving in-page: MetaDescription +0ms status Retrieving in-page: FontSize +0ms status Retrieving in-page: CrawlableLinks +0ms status Retrieving in-page: MetaRobots +0ms status Retrieving in-page: Hreflang +0ms status Retrieving in-page: EmbeddedContent +0ms status Retrieving in-page: Canonical +0ms status Retrieving in-page: RobotsTxt +0ms status Retrieving trace +1ms status Retrieving devtoolsLog & network records +110ms status Retrieving: Scripts +27ms status Retrieving: CSSUsage +53ms status Retrieving: Viewport +192ms status Retrieving: ViewportDimensions +5ms status Retrieving: ThemeColor +13ms status Retrieving: Manifest +2ms status Retrieving: RuntimeExceptions +295ms status Retrieving: ChromeConsoleMessages +1ms status Retrieving: ImageUsage +2ms status Retrieving: Accessibility +22ms status Retrieving: LinkElements +526ms status Retrieving: AnchorsWithNoRelNoopener +10ms status Retrieving: AppCacheManifest +6ms status Retrieving: Doctype +20ms status Retrieving: DOMStats +4ms status Retrieving: JSLibraries +50ms status Retrieving: OptimizedImages +25ms status Retrieving: PasswordInputsWithPreventedPaste +234ms status Retrieving: ResponseCompression +3ms status Retrieving: TagsBlockingFirstPaint +7ms status Retrieving: MetaDescription +6ms status Retrieving: FontSize +7ms status Retrieving: CrawlableLinks +245ms status Retrieving: MetaRobots +6ms status Retrieving: Hreflang +2ms status Retrieving: EmbeddedContent +2ms status Retrieving: Canonical +3ms status Retrieving: RobotsTxt +6ms status Resetting state with about:blank +19ms status Loading page & waiting for onload ServiceWorker, Offline, StartUrl +24ms status Retrieving in-page: ServiceWorker +59ms status Retrieving in-page: Offline +0ms status Retrieving in-page: StartUrl +1ms status Retrieving devtoolsLog & network records +0ms status Retrieving: ServiceWorker +2ms status Retrieving: Offline +1ms status Retrieving: StartUrl +1ms status Resetting state with about:blank +5ms status Loading page & waiting for onload HTTPRedirect, HTMLWithoutJavaScript +48ms status Retrieving in-page: HTTPRedirect +260ms status Retrieving in-page: HTMLWithoutJavaScript +0ms status Retrieving devtoolsLog & network records +0ms status Retrieving: HTTPRedirect +7ms status Retrieving: HTMLWithoutJavaScript +12ms status Disconnecting from browser... +7ms status Analyzing and running audits... +6ms status Evaluating: Uses HTTPS +3ms status Evaluating: Redirects HTTP traffic to HTTPS +24ms status Evaluating: Registers a service worker that controls page and start_url +1ms status Evaluating: Current page responds with a 200 when offline +0ms status Evaluating: Has a `<meta name="viewport">` tag with `width` or `initial-scale` +1ms status Evaluating: Contains some content when JavaScript is not available +1ms status Evaluating: First Contentful Paint +6ms status Evaluating: First Meaningful Paint +54ms status Evaluating: Page load is fast enough on mobile networks +10ms status Evaluating: Speed Index +33ms status Evaluating: Screenshot Thumbnails +529ms status Evaluating: Final Screenshot +287ms status Evaluating: Estimated Input Latency +2ms status Evaluating: No browser errors logged to the console +16ms status Evaluating: Server response times are low (TTFB) +1ms status Evaluating: First CPU Idle +1ms status Evaluating: Time to Interactive +30ms status Evaluating: User Timing marks and measures +0ms status Evaluating: Minimize Critical Requests Depth +2ms status Evaluating: Avoid multiple page redirects +3ms status Evaluating: Web app manifest meets the installability requirements +2ms status Evaluating: Configured for a custom splash screen +1ms status Evaluating: Sets an address-bar theme color +0ms status Evaluating: Content is sized correctly for the viewport +1ms status Evaluating: Displays images with correct aspect ratio +0ms status Evaluating: Avoids deprecated APIs +1ms status Evaluating: Minimizes main-thread work +0ms status Evaluating: JavaScript execution time +11ms status Evaluating: Preload key requests +3ms status Evaluating: Preconnect to required origins +2ms status Evaluating: All text remains visible during webfont loads +2ms status Evaluating: Network Requests +1ms status Evaluating: Metrics +2ms status Evaluating: start_url responds with a 200 when offline +1ms status Evaluating: Site works cross-browser +1ms status Evaluating: Page transitions don't feel like they block on the network +0ms status Evaluating: Each page has a URL +0ms status Evaluating: `[aria-*]` attributes match their roles +1ms status Evaluating: `[role]`s have all required `[aria-*]` attributes +1ms status Evaluating: Elements with `[role]` that require specific children `[role]`s, are present +0ms status Evaluating: `[role]`s are contained by their required parent element +1ms status Evaluating: `[role]` values are valid +1ms status Evaluating: `[aria-*]` attributes have valid values +0ms status Evaluating: `[aria-*]` attributes are valid and not misspelled +1ms status Evaluating: `<audio>` elements contain a `<track>` element with `[kind="captions"]` +1ms status Evaluating: Buttons have an accessible name +1ms status Evaluating: The page contains a heading, skip link, or landmark region +1ms status Evaluating: Background and foreground colors have a sufficient contrast ratio +1ms status Evaluating: `<dl>`'s contain only properly-ordered `<dt>` and `<dd>` groups, `<script>` or `<template>` elements. +1ms status Evaluating: Definition list items are wrapped in `<dl>` elements +0ms status Evaluating: Document has a `<title>` element +1ms status Evaluating: `[id]` attributes on the page are unique +1ms status Evaluating: `<frame>` or `<iframe>` elements have a title +1ms status Evaluating: `<html>` element has a `[lang]` attribute +0ms status Evaluating: `<html>` element has a valid value for its `[lang]` attribute +1ms status Evaluating: Image elements have `[alt]` attributes +1ms status Evaluating: `<input type="image">` elements have `[alt]` text +1ms status Evaluating: Form elements have associated labels +0ms status Evaluating: Presentational `<table>` elements avoid using `<th>`, `<caption>` or the `[summary]` attribute. +1ms status Evaluating: Links have a discernible name +1ms status Evaluating: Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`). +1ms status Evaluating: List items (`<li>`) are contained within `<ul>` or `<ol>` parent elements +1ms status Evaluating: The document does not use `<meta http-equiv="refresh">` +0ms status Evaluating: `[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5. +1ms status Evaluating: `<object>` elements have `[alt]` text +1ms status Evaluating: No element has a `[tabindex]` value greater than 0 +1ms status Evaluating: Cells in a `<table>` element that use the `[headers]` attribute only refer to other cells of that same table. +1ms status Evaluating: `<th>` elements and elements with `[role="columnheader"/"rowheader"]` have data cells they describe. +0ms status Evaluating: `[lang]` attributes have a valid value +1ms status Evaluating: `<video>` elements contain a `<track>` element with `[kind="captions"]` +1ms status Evaluating: `<video>` elements contain a `<track>` element with `[kind="description"]` +1ms status Evaluating: `[accesskey]` values are unique +1ms status Evaluating: Custom controls have associated labels +0ms status Evaluating: Custom controls have ARIA roles +1ms status Evaluating: User focus is not accidentally trapped in a region +0ms status Evaluating: Interactive controls are keyboard focusable +0ms status Evaluating: Headings don't skip levels +0ms status Evaluating: Interactive elements indicate their purpose and state +1ms status Evaluating: The page has a logical tab order +0ms status Evaluating: The user's focus is directed to new content added to the page +1ms status Evaluating: Offscreen content is hidden from assistive technology +0ms status Evaluating: HTML5 landmark elements are used to improve navigation +0ms status Evaluating: Visual order on the page follows DOM order +0ms status Evaluating: Uses efficient cache policy on static assets +1ms status Evaluating: Avoids enormous network payloads +3ms status Evaluating: Defer offscreen images +1ms status Evaluating: Eliminate render-blocking resources +12ms status Evaluating: Minify CSS +28ms status Evaluating: Minify JavaScript +64ms status Evaluating: Defer unused CSS +69ms status Evaluating: Serve images in next-gen formats +12ms status Evaluating: Efficiently encode images +11ms status Evaluating: Enable text compression +6ms status Evaluating: Properly size images +6ms status Evaluating: Use video formats for animated content +7ms status Evaluating: Avoids Application Cache +11ms status Evaluating: Page has the HTML doctype +0ms status Evaluating: Avoids an excessive DOM size +1ms status Evaluating: Links to cross-origin destinations are safe +2ms status Evaluating: Avoids requesting the geolocation permission on page load +1ms status Evaluating: Avoids `document.write()` +0ms status Evaluating: Avoids front-end JavaScript libraries with known security vulnerabilities +0ms status Evaluating: Detected JavaScript libraries +9ms status Evaluating: Avoids requesting the notification permission on page load +1ms status Evaluating: Allows users to paste into password fields +0ms status Evaluating: Uses HTTP/2 for its own resources +0ms status Evaluating: Uses passive listeners to improve scrolling performance +1ms status Evaluating: Document has a meta description +0ms status Evaluating: Page has successful HTTP status code +1ms status Evaluating: Document uses legible font sizes +5ms status Evaluating: Links have descriptive text +1ms status Evaluating: Page isn’t blocked from indexing +1ms status Evaluating: robots.txt is valid +2ms status Evaluating: Document has a valid `hreflang` +1ms status Evaluating: Document avoids plugins +1ms status Evaluating: Document has a valid `rel=canonical` +0ms status Evaluating: Page is mobile friendly +1ms status Evaluating: Structured data is valid +0ms status Generating results... +0ms ChromeLauncher Killing Chrome instance 7098 +59ms Printer html output written to /home/chandan/techblog.co.rs.com_2019-01-20_19-29-35.report.html +46ms CLI Protip: Run lighthouse with `--view` to immediately open the HTML report in your browser +1ms
U poslednjem redu, možete videti putanju do izveštaja. Podrazumevano, izveštaj se generiše u HTML formatu, a možete ga pregledati preuzimanjem ili postavljanjem na web server.
Šta ako želite izveštaj u JSON formatu?
To je moguće na sledeći način:
lighthouse URL --chrome-flags="--headless" --output json --output-path URL.json
Korišćenjem Lighthouse CLI, imate potpunu kontrolu nad alatom i možete ga koristiti po potrebi. Preporučuje se da pregledate GitHub repozitorijum za više informacija o korišćenju CLI-a ili programski.
Zaključak
Google Lighthouse se čini kao veoma koristan alat za kontinuirano testiranje i poboljšanje performansi i upotrebljivosti sajta. Ako koristite WordPress i želite da vaš sajt učitava brže, pogledajte WP Rocket.