CDNフル活用でつくる、高速Webアプリ / Using CDN To Improve Web Performance

Transcript

1. CDNフル活用でつくる
   高速Webアプリ
   ~ こえのブログ実装例 ~
   Oct. 23 2019, Yamagoya 2019
   Kazunari Hara, CyberAgent
   Using CDN To Improve Web Performance
   

   View Slide

2. CyberAgent Web Team is now on
   Performance Accessibility Security
   

   View Slide

3. CyberAgent Web Team is now on
   WebパフォーマンスとプロダクトKPIの相関を可視化
   する話 https://developers.cyberagent.co.jp/blog/archives/9540/
   アクセシビリティへの取り組み
   https://www.cyberagent.co.jp/way/csr/accessibility/
   アメブロ2017 – 大規模サービスhttps化
   https://developers.cyberagent.co.jp/blog/archives/7743/
   

   View Slide

4. CyberAgent Web Team is now
   

   View Slide

5. View Slide

6. Posting a blog entry just by speaking
   

   View Slide

7. こんにちは 今日はFastly
   山小屋にきました
   Cloud
   Speech-to-Text
   

   View Slide

8. こえのブログ
   is
   

   View Slide

9. https://twitter.com/sisidovski/status/1158980641955823616
   Lighthouse
   score with
   firework
   

   View Slide

10. Performance:
    - Fast
    - Consistant
    

    View Slide

11. “Spike” -
    a sharp increase
    in the
    magnitude or
    concentration of
    visitors
    Spike reasons:
    - Breaking news
    - Launch days
    - Disasters
    - Bots
    - System issues
    

    View Slide

12. When your site is slow...
    

    View Slide

13. When your site is down...
    

    View Slide

14. Cache helps
    performance
    improvement by
    reusing
    resources and
    removing
    unnecessary
    calculation on
    servers
    Origin
    CDN
    

    View Slide

15. こえのブログ
    is made with
    Fastly and
    GCP to
    maintain
    backends
    more easily
    

    View Slide

16. Cache Stats of こえのブログ
    

    View Slide

17. 98%
    cache hit ratio on
    CDN
    

    View Slide

18. 98% cache hit
    ratio on CDN
    if you have
    cats
    

    View Slide

19. 98% cache hit
    ratio on CDN
    if you have
    cats
    

    View Slide

20. 99%
    cache coverage
    on CDN
    

    View Slide

21. 99% cache
    coverage on
    CDN if you
    have cats
    

    View Slide

22. 99% cache
    coverage on
    CDN if you
    have cats
    

    View Slide

23. 98%
    cache coverage
    in browser on
    repeat view
    

    View Slide

24. Fast and
    consistent
    even during
    spike as CDN
    returns cache
    CDN Origin
    Client
    98%
    

    View Slide

25. Less network
    access on
    repeat view CDN Origin
    Client
    98%
    

    View Slide

26. Cache Strategy
    

    View Slide

27. Cache strategy
    - Keep resources static
    - Define consistent URLs
    - Set long cache time (TTL)
    - Divide endpoint if the resource
    changes frequently
    - Tagging cacheable resources and
    purging if necessary
    

    View Slide

28. Static:
    - Same for everyone
    - Cacheable
    Dynamic:
    - Variable by user/session
    - Hard to cache efficiently
    Keep as many
    resources
    static as
    possible
    

    View Slide

29. Keep as many
    resources
    static as
    possible
    Web App Assets:
    Entry Assets:
    {

    “id”: “12345”, 

    “title”: “voice” 

    }

    

    

    View Slide

30. Most
    resources of
    こえのブログ
    are static since
    the app was
    made by a
    Client Side
    Rendering
    (CSR) App
    {

    “id”: “12345”, 

    “title”: “voice” 

    }

    

    Fetch data from JS
    when necessary
    

    View Slide

31. User data is
    rendered
    asynchronousl
    y
    Displayed later
    than ranking
    

    View Slide

32. Define
    consistent
    URLs using
    HTTP methods
    GET
    - Retrieve resource
    information only
    - Do not change the state
    of the resource
    - Return the same result
    every time
    

    View Slide

33. Define
    consistent
    URLs using
    HTTP methods
    POST/PUT/DELETE
    - create/update/delete
    resources
    - Not cacheable
    

    View Slide

34. Define
    resources as
    cacheable or
    not
    Cacheable:
    - Most GET endpoints
    Not cacheable:
    - Few GET endpoints with
    session
    - Few POST/PUT/DELETE
    endpoints
    

    View Slide

35. URL example
    GET /
    GET /editor
    GET /src/**/*.js
    GET /images/**/*.{png|jpeg|svg}
    GET /assets/audios/${userId}/${entryId}/
    GET /assets/images/${userId}/${entryId}/
    GET /api/entry/${userId}/${entryId}/
    POST /api/entry/${userId}/
    PUT /api/entry/${userId}/${entryId}/
    DELETE /api/entry/${userId}/${entryId}/
    GET /api/auth/${userId}/status/
    Cacheable
    

    View Slide

36. 93%
    of endpoints are
    cacheable
    

    View Slide

37. Set cache TTL
    as long as
    possible
    Response header for
    CDN:
    “Surrogate-Control: max-age=”
    - Default: 2592000 (30 days)
    - Fallback: 86400 (1 day)
    

    View Slide

38. Set cache TTL
    as long as
    possible
    Response header for
    browsers:
    “Cache-Control: max-age=”
    - Default: ※
    120 (2 minutes)
    - Fallback: 86400 (1 day)
    ※ Enabled longer cache with service worker
    

    View Slide

39. Divide
    endpoint if the
    resource
    changes
    frequently
    Entry
    {
    “id”: “12345”,
    “title”: “voice”,
    “view-count”:
    2946
    }
    Meta data is
    immutable
    View count
    changes
    frequently
    

    View Slide

40. Divide
    endpoint if the
    resource
    changes
    frequently
    Response header for
    stale content:
    “Stale-While-Revalidate:”
    CDN Origin
    Update data in background
    

    View Slide

41. Tagging
    cacheable
    resources with
    surrogate key
    “webapp” “blogger/
    ameba”
    “entry/12345 blogger/ameba”
    

    View Slide

42. Purge the tag
    when
    resources have
    been updated
    New version release
    curl -XPOST -H “Fastly-Key:${KEY}” \n
    -H “Accept:application/json” \n
    “https://api.fastly.com/service/${SERVICE}/pu
    rge/webapp”
    

    View Slide

43. Purge the tag
    when
    resources have
    been updated
    Data updated
    curl -XPOST -H “Fastly-Key:${KEY}” \n
    -H “Accept:application/json” \n
    -H “Surrogate-Key:blogger/ameba
    entry/12345” \n
    “https://api.fastly.com/service/...”
    Cloud
    Filestore
    

    View Slide

44. These key
    ideas are also
    useful even
    when your
    app uses
    server side
    rendering
    (SSR)
    To be continued in the
    fastly meetup #3
    

    View Slide

45. Backends
    

    View Slide

46. Cloud
    Filestore
    Cloud
    Storage
    Cloud
    Functions
    Stable Serverless with Fastly and
    GCP
    - High CDN cache coverage
    - Event-driven execution
    - Auto scalling
    - Deployability
    

    View Slide

47. Cloud Storage
    Static files in Cloud
    Storage
    - Scalable
    - As an origin server
    - HMAC Authentication
    https://docs.fastly.com/en/guides/google-cloud-storage
    

    View Slide

48. Cloud Storage
    Cloud Filestore
    Event-driven functions
    Cloud Functions
    Some actions
    Event
    Cloud Storage
    

    View Slide

49. onDatabaseUpdate
    Cloud Filestore Cloud Functions
    Update
    entryId: 12345
    Purge
    Surrogate-Key: entry/12345
    

    View Slide

50. onDatabaseDelete
    Cloud Filestore Cloud Functions
    Delete
    entryId: 12345
    Purge
    Surrogate-Key: entry/12345
    Cloud Storage
    Delete audio
    

    View Slide

51. “deployability”
    is an important
    metric for app
    quality
    Over 1,000
    web app releasesin 10 month
    Over 200
    VCL deploymentsin 10 month
    

    View Slide

52. https://speakerdeck.com/herablog/web-app-checklist-2019-at-inside-frontend?slide=134
    

    View Slide

53. Browser Cache
    

    View Slide

54. Browser cache
    strategy
    No Service Worker:
    - Cache-Control header
    Service Worker:
    - Precaching
    - Runtime caching
    Service Worker is available in most modern browsers today
    

    View Slide

55. Web app
    assets are
    cached with
    service worker
    at first visit
    and are never
    re-fetched
    until updated
    // service-worker.js
    workbox.precaching.precacheAndRoute([
    {
    url: "images/title_service_header.svg",
    revision: "6a048b548112674c9e65ed"
    },
    {
    url: "index.html",
    revision: "6805b47012688211c81521"
    },
    {
    url: "src/components/voice-app.js",
    revision: "fdf10df6f530cbce55c8f5"
    },
    ...
    ]);
    

    View Slide

56. Other
    resources are
    cached as
    runtime cache
    and can be
    used when
    offline
    CDN
    

    View Slide

57. VCL Recipes
    

    View Slide

58. Cache key to
    normalize
    method=${req.request};
    origin=${req.http.host};
    url=${req.url};
    vary=${req.http.Accept-Encoding};
    URL and vary can be
    variable
    

    View Slide

59. Query
    normalization
    import querystring;
    sub vcl_recv {
    set req.url = querystring.sort(req.url);
    set req.url = querystring.regfilter_except(
    req.url,
    "^(language|format|offset|limit)$"
    );
    }
    https://docs.fastly.com/vcl/query-string-manipulation/
    

    View Slide

60. Vary
    normalization
    sub vcl_recv {
    if (req.http.User-Agent !~ "Edge" &&
    req.http.User-Agent ~ "Chrome/([^.]*)") {
    set req.http.X-UA = "esm";
    } else {
    set req.http.X-UA = "es5";
    }
    }
    sub vcl_fetch {
    set beresp.http.Vary =
    "Accept-Encoding, X-UA";
    }
    https://docs.fastly.com/vcl/query-string-manipulation/
    

    View Slide

61. Basic Auth
    table customer_keys {
    "Basic a2FrZXJ1OmthZXJ1": "kakeru",
    "Basic a2FlcnU6a2FrZXJ1": "kaeru"
    }
    sub vcl_recv {
    if (!table.lookup(
    customer_keys,
    req.http.Authorization
    )) {
    error 401 "Restricted";
    }
    }
    https://docs.fastly.com/en/guides/basic-authentication
    

    View Slide

62. Basic Auth
    sub vcl_error {
    if (obj.status == 401) {
    set obj.http.Content-Type = "text/html;
    charset=utf-8";
    set obj.http.WWW-Authenticate = "Basic
    realm=Secured";
    synthetic {".."};
    return (deliver);
    }
    }
    https://docs.fastly.com/en/guides/basic-authentication
    

    View Slide

63. Access control
    acl office_ip_ranges {
    "192.0.2.0"/24;
    "198.51.100.4";
    }
    sub vcl_recv {
    if (!(client.ip ~ office_ip_ranges)) {
    error 403 "Forbidden";
    }
    }
    https://docs.fastly.com/en/guides/about-acls
    

    View Slide

64. Routing to
    different
    origins
    sub assets_origin {
    set req.backend = F_assets_origin;
    set req.http.host = "${api-assets-domain}";
    }
    sub api_origin {
    set req.backend = F_api_origin;
    set req.http.host = "${api-org-domain}";
    }
    sub vcl_recv {
    if (req.url.path ~ "^/assets/") {
    call assets_origin;
    } else if (req.url.path ~ "^/api/") {
    call api_origin;
    }...
    }
    

    View Slide

65. Adding
    surrogate key
    sub vcl_fetch {
    declare local var.SurrogateKey STRING;
    set var.SurrogateKey = "assets";
    if (req.http.x-url ~
    "/audios/standard/([a-z0-9-]{3,24})/([a-zA-Z0-9]+)") {
    set var.SurrogateKey =
    var.SurrogateKey + " blogger/" + re.group.1 + " entry/"
    + re.group.2;
    }
    set beresp.http.Surrogate-Key = var.SurrogateKey;
    }
    Extracting keys
    from URL path
    

    View Slide

66. Modifying
    response
    headers
    sub vcl_deliver {
    unset resp.http.via;
    unset resp.http.server;
    add resp.http.Server-Timing =
    fastly_info.state {", fastly;desc="Edge time";dur="}
    time.elapsed.msec;
    set resp.http.Referrer-Policy = "origin-when-cross-origin";
    set resp.http.Strict-Transport-Security = "max-age=31536000";
    set resp.http.X-Content-Type-Options = "nosniff";
    add resp.http.Content-Security-Policy = "default-src 'self';...”
    add resp.http.Content-Security-Policy =
    "upgrade-insecure-requests";
    }
    Removing unnecessary
    headrers
    Adding useful headers
    

    View Slide

67. (CDN) makes your app
    stable, predictable,
    efficient, deployable and
    enjoyable
    

    View Slide

68. (CDN) makes your app
    

    View Slide

69. @herablog
    Related documents:
    - アメブロ2019: こえのブログでのPWA
    https://developers.cyberagent.co.jp/blog/archives/20506/
    - Web App Checklist 〜高品質のWebアプリケーションをつくる
    ために〜
    https://speakerdeck.com/herablog/web-app-checklist-2019-at-inside-frontend
    - こえのブログでのPWA ~ PWA編 ~
    https://speakerdeck.com/herablog/pwa-night-vol-dot-4
    - こえのブログでのPWA ~ 開発現場編 ~
    https://speakerdeck.com/herablog/koe-no-blog-pwa
    - 最新CDN入門 WEB+DB PRESS Vol.109
    https://gihyo.jp/magazine/wdpress/archive/2019/vol109
    

    View Slide