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Dynamically Sassy

Dynamically Sassy

Generating dynamic CSS in Ruby on Rails

Jeremy Fairbank

April 22, 2015
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Transcript

  1. Dynamically Sassy
    Generating Dynamic CSS in Rails
    Jeremy Fairbank

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  2. What are we
    going to talk
    about?

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  3. Generate dynamic CSS

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  4. Write Sass functions in Ruby

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  5. Identify performance issues

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  6. Caching and background
    processing

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  7. Hi, I'm Jeremy
    ...or
    @elpapapollo

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  8. pushagency.io

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  9. simplybuilt.com

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  10. Our Problem

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  11. Implementation
    Issues

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  12. Same Sass style sheet for
    default and custom color
    palettes

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  13. Rendering custom color style
    sheets from a controller

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  14. Slow Sass render times

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  15. Caching generated CSS

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  16. Rendering in a worker

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  17. Syntactically Awesome Style Sheets
    sass-lang.com

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  18. /
    / V
    a
    r
    i
    a
    b
    l
    e
    s
    $
    f
    o
    n
    t
    -
    s
    i
    z
    e
    : 1
    2
    p
    x
    ;
    /
    / N
    e
    s
    t
    e
    d r
    u
    l
    e
    s
    #
    f
    o
    o {
    .
    b
    a
    r {
    f
    o
    n
    t
    -
    s
    i
    z
    e
    : $
    f
    o
    n
    t
    -
    s
    i
    z
    e
    ;
    }
    }
    /
    / I
    n
    c
    l
    u
    d
    e o
    t
    h
    e
    r S
    a
    s
    s s
    t
    y
    l
    e s
    h
    e
    e
    t
    s
    @
    i
    m
    p
    o
    r
    t '
    b
    a
    r
    '
    ;
    /
    / M
    i
    x
    i
    n
    s
    @
    m
    i
    x
    i
    n h
    a
    s
    -
    c
    a
    t
    s {
    &
    :
    :
    b
    e
    f
    o
    r
    e {
    c
    o
    n
    t
    e
    n
    t
    : '
    m
    e
    o
    w
    '
    ;
    d
    i
    s
    p
    l
    a
    y
    : b
    l
    o
    c
    k
    ;
    }
    }
    #
    i
    n
    t
    e
    r
    n
    e
    t {
    @
    i
    n
    c
    l
    u
    d
    e h
    a
    s
    -
    c
    a
    t
    s
    ;
    }

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  19. So What?

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  20. Modularity

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  21. DRY

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  22. Data Structures

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  23. Scripting

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  24. Color Functions

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  25. That's Sass

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  26. Reusing style
    sheets

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  27. It's all in the
    variables

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  28. Static Context

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  29. /
    / _
    m
    y
    -
    u
    i
    .
    s
    c
    s
    s
    #
    f
    o
    o {
    b
    a
    c
    k
    g
    r
    o
    u
    n
    d
    : n
    t
    h
    (
    $
    p
    a
    l
    e
    t
    t
    e
    , 1
    )
    ;
    c
    o
    l
    o
    r
    : n
    t
    h
    (
    $
    p
    a
    l
    e
    t
    t
    e
    , 2
    )
    ;
    }
    /
    / p
    a
    l
    e
    t
    t
    e
    1
    .
    s
    c
    s
    s
    $
    p
    a
    l
    e
    t
    t
    e
    : (
    r
    e
    d g
    r
    e
    e
    n
    )
    ;
    @
    i
    m
    p
    o
    r
    t '
    m
    y
    -
    u
    i
    '
    ;
    /
    / p
    a
    l
    e
    t
    t
    e
    2
    .
    s
    c
    s
    s
    $
    p
    a
    l
    e
    t
    t
    e
    : (
    b
    l
    u
    e y
    e
    l
    l
    o
    w
    )
    ;
    @
    i
    m
    p
    o
    r
    t '
    m
    y
    -
    u
    i
    '
    ;

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  30. Dynamic Context

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  31. Sass Functions

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  32. /
    / d
    y
    n
    a
    m
    i
    c
    -
    p
    a
    l
    e
    t
    t
    e
    .
    s
    c
    s
    s
    $
    p
    a
    l
    e
    t
    t
    e
    : g
    e
    t
    -
    d
    y
    n
    a
    m
    i
    c
    -
    p
    a
    l
    e
    t
    t
    e
    (
    )
    ;
    @
    i
    m
    p
    o
    r
    t '
    m
    y
    -
    u
    i
    '
    ;
    # c
    o
    n
    f
    i
    g
    /
    i
    n
    i
    t
    i
    a
    l
    i
    z
    e
    r
    s
    /
    s
    a
    s
    s
    .
    r
    b
    m
    o
    d
    u
    l
    e S
    a
    s
    s
    :
    :
    S
    c
    r
    i
    p
    t
    :
    :
    F
    u
    n
    c
    t
    i
    o
    n
    s
    d
    e
    f g
    e
    t
    _
    d
    y
    n
    a
    m
    i
    c
    _
    p
    a
    l
    e
    t
    t
    e
    p
    a
    l
    e
    t
    t
    e = 2
    .
    t
    i
    m
    e
    s
    .
    m
    a
    p d
    o
    c
    o
    l
    o
    r = '
    #
    %
    0
    6
    x
    ' % (
    r
    a
    n
    d * 0
    x
    f
    f
    f
    f
    f
    f
    )
    S
    a
    s
    s
    :
    :
    S
    c
    r
    i
    p
    t
    :
    :
    V
    a
    l
    u
    e
    :
    :
    C
    o
    l
    o
    r
    .
    f
    r
    o
    m
    _
    h
    e
    x
    (
    c
    o
    l
    o
    r
    )
    e
    n
    d
    S
    a
    s
    s
    :
    :
    S
    c
    r
    i
    p
    t
    :
    :
    V
    a
    l
    u
    e
    :
    :
    L
    i
    s
    t
    .
    n
    e
    w
    (
    p
    a
    l
    e
    t
    t
    e
    , :
    s
    p
    a
    c
    e
    )
    e
    n
    d
    e
    n
    d

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  33. Injecting data
    from a user?

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  34. /
    / a
    p
    p
    /
    a
    s
    s
    e
    t
    s
    /
    s
    t
    y
    l
    e
    s
    h
    e
    e
    t
    s
    /
    d
    y
    n
    a
    m
    i
    c
    -
    p
    a
    l
    e
    t
    t
    e
    -
    r
    a
    i
    l
    s
    .
    c
    s
    s
    .
    s
    c
    s
    s
    $
    p
    a
    l
    e
    t
    t
    e
    : g
    e
    t
    -
    d
    y
    n
    a
    m
    i
    c
    -
    p
    a
    l
    e
    t
    t
    e
    -
    f
    r
    o
    m
    -
    u
    s
    e
    r
    -
    s
    o
    m
    e
    h
    o
    w
    -
    m
    a
    g
    i
    c
    a
    l
    l
    y
    (
    )
    ;
    @
    i
    m
    p
    o
    r
    t '
    m
    y
    -
    u
    i
    '
    ;

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  35. Use the asset
    pipeline?

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  36. "Static" context
    in the tilt
    template

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  37. # s
    a
    s
    s
    -
    r
    a
    i
    l
    s
    /
    l
    i
    b
    /
    s
    a
    s
    s
    /
    r
    a
    i
    l
    s
    /
    t
    e
    m
    p
    l
    a
    t
    e
    .
    r
    b
    m
    o
    d
    u
    l
    e S
    a
    s
    s
    m
    o
    d
    u
    l
    e R
    a
    i
    l
    s
    c
    l
    a
    s
    s S
    a
    s
    s
    T
    e
    m
    p
    l
    a
    t
    e < T
    i
    l
    t
    :
    :
    T
    e
    m
    p
    l
    a
    t
    e
    # .
    .
    .
    d
    e
    f e
    v
    a
    l
    u
    a
    t
    e
    (
    c
    o
    n
    t
    e
    x
    t
    , l
    o
    c
    a
    l
    s
    , &
    b
    l
    o
    c
    k
    )
    c
    a
    c
    h
    e
    _
    s
    t
    o
    r
    e = C
    a
    c
    h
    e
    S
    t
    o
    r
    e
    .
    n
    e
    w
    (
    c
    o
    n
    t
    e
    x
    t
    .
    e
    n
    v
    i
    r
    o
    n
    m
    e
    n
    t
    )
    o
    p
    t
    i
    o
    n
    s = {
    :
    f
    i
    l
    e
    n
    a
    m
    e =
    > e
    v
    a
    l
    _
    f
    i
    l
    e
    ,
    :
    l
    i
    n
    e =
    > l
    i
    n
    e
    ,
    :
    s
    y
    n
    t
    a
    x =
    > s
    y
    n
    t
    a
    x
    ,
    :
    c
    a
    c
    h
    e
    _
    s
    t
    o
    r
    e =
    > c
    a
    c
    h
    e
    _
    s
    t
    o
    r
    e
    ,
    :
    i
    m
    p
    o
    r
    t
    e
    r =
    > i
    m
    p
    o
    r
    t
    e
    r
    _
    c
    l
    a
    s
    s
    .
    n
    e
    w
    (
    c
    o
    n
    t
    e
    x
    t
    .
    p
    a
    t
    h
    n
    a
    m
    e
    .
    t
    o
    _
    s
    )
    ,
    :
    l
    o
    a
    d
    _
    p
    a
    t
    h
    s =
    > c
    o
    n
    t
    e
    x
    t
    .
    e
    n
    v
    i
    r
    o
    n
    m
    e
    n
    t
    .
    p
    a
    t
    h
    s
    .
    m
    a
    p { |
    p
    a
    t
    h
    | i
    m
    p
    o
    r
    t
    e
    r
    _
    c
    l
    a
    s
    s
    .
    n
    e
    w
    (
    p
    a
    t
    h
    .
    t
    o
    _
    s
    ) }
    ,
    :
    s
    p
    r
    o
    c
    k
    e
    t
    s =
    > {
    :
    c
    o
    n
    t
    e
    x
    t =
    > c
    o
    n
    t
    e
    x
    t
    ,
    :
    e
    n
    v
    i
    r
    o
    n
    m
    e
    n
    t =
    > c
    o
    n
    t
    e
    x
    t
    .
    e
    n
    v
    i
    r
    o
    n
    m
    e
    n
    t
    }
    }
    s
    a
    s
    s
    _
    c
    o
    n
    f
    i
    g = c
    o
    n
    t
    e
    x
    t
    .
    s
    a
    s
    s
    _
    c
    o
    n
    f
    i
    g
    .
    m
    e
    r
    g
    e
    (
    o
    p
    t
    i
    o
    n
    s
    )
    e
    n
    g
    i
    n
    e = :
    :
    S
    a
    s
    s
    :
    :
    E
    n
    g
    i
    n
    e
    .
    n
    e
    w
    (
    d
    a
    t
    a
    , s
    a
    s
    s
    _
    c
    o
    n
    f
    i
    g
    )
    c
    s
    s = e
    n
    g
    i
    n
    e
    .
    r
    e
    n
    d
    e
    r
    e
    n
    g
    i
    n
    e
    .
    d
    e
    p
    e
    n
    d
    e
    n
    c
    i
    e
    s
    .
    m
    a
    p d
    o |
    d
    e
    p
    e
    n
    d
    e
    n
    c
    y
    |
    c
    o
    n
    t
    e
    x
    t
    .
    d
    e
    p
    e
    n
    d
    _
    o
    n
    (
    d
    e
    p
    e
    n
    d
    e
    n
    c
    y
    .
    o
    p
    t
    i
    o
    n
    s
    [
    :
    f
    i
    l
    e
    n
    a
    m
    e
    ]
    )
    e
    n
    d
    c
    s
    s
    r
    e
    s
    c
    u
    e :
    :
    S
    a
    s
    s
    :
    :
    S
    y
    n
    t
    a
    x
    E
    r
    r
    o
    r =
    > e
    c
    o
    n
    t
    e
    x
    t
    .
    _
    _
    L
    I
    N
    E
    _
    _ = e
    .
    s
    a
    s
    s
    _
    b
    a
    c
    k
    t
    r
    a
    c
    e
    .
    f
    i
    r
    s
    t
    [
    :
    l
    i
    n
    e
    ]
    r
    a
    i
    s
    e e
    e
    n
    d
    # .
    .
    .
    e
    n
    d
    e
    n
    d
    e
    n
    d

    View Slide

  38. Oh, and assets are precompiled
    for production

    View Slide

  39. We need our own render class
    for dynamic content

    View Slide

  40. S
    a
    s
    s
    :
    :
    E
    n
    g
    i
    n
    e
    to the rescue

    View Slide

  41. # l
    i
    b
    /
    s
    a
    s
    s
    _
    c
    u
    s
    t
    o
    m
    _
    p
    a
    l
    e
    t
    t
    e
    .
    r
    b
    c
    l
    a
    s
    s S
    a
    s
    s
    C
    u
    s
    t
    o
    m
    P
    a
    l
    e
    t
    t
    e
    T
    E
    M
    P
    L
    A
    T
    E = <
    <
    -
    E
    O
    S
    .
    f
    r
    e
    e
    z
    e
    $
    p
    a
    l
    e
    t
    t
    e
    : g
    e
    t
    -
    c
    u
    s
    t
    o
    m
    -
    p
    a
    l
    e
    t
    t
    e
    (
    )
    ;
    @
    i
    m
    p
    o
    r
    t '
    m
    y
    -
    u
    i
    '
    ;
    E
    O
    S
    d
    e
    f i
    n
    i
    t
    i
    a
    l
    i
    z
    e
    (
    c
    o
    l
    o
    r
    )
    @
    c
    o
    l
    o
    r = c
    o
    l
    o
    r
    e
    n
    d
    d
    e
    f r
    e
    n
    d
    e
    r
    S
    a
    s
    s
    :
    :
    E
    n
    g
    i
    n
    e
    .
    n
    e
    w
    (
    T
    E
    M
    P
    L
    A
    T
    E
    , s
    a
    s
    s
    _
    c
    u
    s
    t
    o
    m
    _
    o
    p
    t
    i
    o
    n
    s
    )
    .
    r
    e
    n
    d
    e
    r
    e
    n
    d
    p
    r
    i
    v
    a
    t
    e
    d
    e
    f s
    a
    s
    s
    _
    c
    u
    s
    t
    o
    m
    _
    o
    p
    t
    i
    o
    n
    s
    { s
    y
    n
    t
    a
    x
    : :
    s
    c
    s
    s
    ,
    s
    t
    y
    l
    e
    : :
    e
    x
    p
    a
    n
    d
    e
    d
    ,
    c
    u
    s
    t
    o
    m
    : { c
    o
    l
    o
    r
    : @
    c
    o
    l
    o
    r } }
    e
    n
    d
    e
    n
    d

    View Slide

  42. # c
    o
    n
    f
    i
    g
    /
    i
    n
    i
    t
    i
    a
    l
    i
    z
    e
    r
    s
    /
    s
    a
    s
    s
    .
    r
    b
    m
    o
    d
    u
    l
    e S
    a
    s
    s
    :
    :
    S
    c
    r
    i
    p
    t
    :
    :
    F
    u
    n
    c
    t
    i
    o
    n
    s
    d
    e
    f g
    e
    t
    _
    c
    u
    s
    t
    o
    m
    _
    p
    a
    l
    e
    t
    t
    e
    c
    o
    l
    o
    r = S
    a
    s
    s
    :
    :
    S
    c
    r
    i
    p
    t
    :
    :
    V
    a
    l
    u
    e
    :
    :
    C
    o
    l
    o
    r
    .
    f
    r
    o
    m
    _
    h
    e
    x
    (
    o
    p
    t
    i
    o
    n
    s
    [
    :
    c
    u
    s
    t
    o
    m
    ]
    [
    :
    c
    o
    l
    o
    r
    ]
    )
    f
    a
    c
    t
    o
    r = S
    a
    s
    s
    :
    :
    S
    c
    r
    i
    p
    t
    :
    :
    V
    a
    l
    u
    e
    :
    :
    N
    u
    m
    b
    e
    r
    .
    n
    e
    w
    (
    2
    0
    , '
    %
    '
    )
    p
    a
    l
    e
    t
    t
    e = [
    l
    i
    g
    h
    t
    e
    n
    (
    c
    o
    l
    o
    r
    , f
    a
    c
    t
    o
    r
    )
    ,
    d
    a
    r
    k
    e
    n
    (
    c
    o
    l
    o
    r
    , f
    a
    c
    t
    o
    r
    )
    ]
    S
    a
    s
    s
    :
    :
    S
    c
    r
    i
    p
    t
    :
    :
    V
    a
    l
    u
    e
    :
    :
    L
    i
    s
    t
    .
    n
    e
    w
    (
    p
    a
    l
    e
    t
    t
    e
    , :
    s
    p
    a
    c
    e
    )
    e
    n
    d
    e
    n
    d

    View Slide

  43. # a
    p
    p
    /
    c
    o
    n
    t
    r
    o
    l
    l
    e
    r
    s
    /
    p
    a
    l
    e
    t
    t
    e
    s
    _
    c
    o
    n
    t
    r
    o
    l
    l
    e
    r
    .
    r
    b
    c
    l
    a
    s
    s P
    a
    l
    e
    t
    t
    e
    s
    C
    o
    n
    t
    r
    o
    l
    l
    e
    r < A
    p
    p
    l
    i
    c
    a
    t
    i
    o
    n
    C
    o
    n
    t
    r
    o
    l
    l
    e
    r
    d
    e
    f c
    u
    s
    t
    o
    m
    _
    p
    a
    l
    e
    t
    t
    e
    c
    u
    s
    t
    o
    m
    _
    r
    e
    n
    d
    e
    r
    e
    r = S
    a
    s
    s
    C
    u
    s
    t
    o
    m
    P
    a
    l
    e
    t
    t
    e
    .
    n
    e
    w
    (
    p
    a
    r
    a
    m
    s
    [
    :
    c
    u
    s
    t
    o
    m
    _
    c
    o
    l
    o
    r
    ]
    )
    @
    c
    s
    s = c
    u
    s
    t
    o
    m
    _
    r
    e
    n
    d
    e
    r
    e
    r
    .
    r
    e
    n
    d
    e
    r
    e
    n
    d
    e
    n
    d
    -
    # a
    p
    p
    /
    v
    i
    e
    w
    s
    /
    p
    a
    l
    e
    t
    t
    e
    s
    /
    c
    u
    s
    t
    o
    m
    _
    p
    a
    l
    e
    t
    t
    e
    .
    c
    s
    s
    .
    h
    a
    m
    l
    = @
    c
    s
    s
    .
    h
    t
    m
    l
    _
    s
    a
    f
    e

    View Slide

  44. Try it out...

    View Slide

  45. S
    a
    s
    s
    :
    :
    S
    y
    n
    t
    a
    x
    E
    r
    r
    o
    r - F
    i
    l
    e t
    o i
    m
    p
    o
    r
    t n
    o
    t f
    o
    u
    n
    d o
    r u
    n
    r
    e
    a
    d
    a
    b
    l
    e
    : m
    y
    -
    u
    i
    .
    -
    _
    _
    -

    View Slide

  46. There's always a
    load path

    View Slide

  47. c
    l
    a
    s
    s S
    a
    s
    s
    C
    u
    s
    t
    o
    m
    P
    a
    l
    e
    t
    t
    e
    p
    r
    i
    v
    a
    t
    e
    d
    e
    f l
    o
    a
    d
    _
    p
    a
    t
    h
    s
    r
    o
    o
    t = R
    a
    i
    l
    s
    .
    r
    o
    o
    t
    .
    j
    o
    i
    n
    (
    '
    a
    p
    p
    '
    , '
    a
    s
    s
    e
    t
    s
    '
    , '
    s
    t
    y
    l
    e
    s
    h
    e
    e
    t
    s
    '
    )
    D
    i
    r
    [
    r
    o
    o
    t
    .
    j
    o
    i
    n
    (
    '
    i
    n
    c
    l
    u
    d
    e
    s
    '
    )
    ]
    e
    n
    d
    d
    e
    f s
    a
    s
    s
    _
    c
    u
    s
    t
    o
    m
    _
    o
    p
    t
    i
    o
    n
    s
    { s
    y
    n
    t
    a
    x
    : :
    s
    c
    s
    s
    ,
    s
    t
    y
    l
    e
    : :
    e
    x
    p
    a
    n
    d
    e
    d
    ,
    l
    o
    a
    d
    _
    p
    a
    t
    h
    s
    : l
    o
    a
    d
    _
    p
    a
    t
    h
    s
    ,
    c
    u
    s
    t
    o
    m
    : { c
    o
    l
    o
    r
    : @
    c
    o
    l
    o
    r } }
    e
    n
    d
    e
    n
    d
    /
    / a
    p
    p
    /
    a
    s
    s
    e
    t
    s
    /
    s
    t
    y
    l
    e
    s
    h
    e
    e
    t
    s
    /
    i
    n
    c
    l
    u
    d
    e
    s
    /
    _
    m
    y
    -
    u
    i
    .
    s
    c
    s
    s
    #
    f
    o
    o {
    b
    a
    c
    k
    g
    r
    o
    u
    n
    d
    : n
    t
    h
    (
    $
    p
    a
    l
    e
    t
    t
    e
    , 1
    )
    ;
    c
    o
    l
    o
    r
    : n
    t
    h
    (
    $
    p
    a
    l
    e
    t
    t
    e
    , 2
    )
    ;
    }

    View Slide

  48. Dynamic Sass Demo
    sassy-demos.jeremyfairbank.com/palettes

    View Slide

  49. Implementing in
    SimplyBuilt

    View Slide

  50. GET
    /custom_palette.css?
    custom_color=%23f00

    View Slide

  51. ...waiting
    ...waiting
    ...waiting

    View Slide

  52. Done!

    View Slide

  53. View Slide

  54. What's the
    problem?

    View Slide

  55. Slow render
    times
    (1-1.5 seconds!)

    View Slide

  56. Complex Sass
    rules

    View Slide

  57. Many file
    dependencies

    View Slide

  58. Loops

    View Slide

  59. Data structure
    lookups

    View Slide

  60. Compass
    functions

    View Slide

  61. Can impact the
    whole server

    View Slide

  62. Web Server

    View Slide

  63. Web Server

    View Slide

  64. Web Server

    View Slide

  65. Web Server

    View Slide

  66. Web Server

    View Slide

  67. Yup, we need
    caching

    View Slide

  68. Memcached
    /
    memcached.org github.com/mperham/dalli

    View Slide

  69. # c
    o
    n
    f
    i
    g
    /
    e
    n
    v
    i
    r
    o
    n
    m
    e
    n
    t
    s
    /
    p
    r
    o
    d
    u
    c
    t
    i
    o
    n
    .
    r
    b
    c
    o
    n
    f
    i
    g
    .
    c
    a
    c
    h
    e
    _
    s
    t
    o
    r
    e = :
    m
    e
    m
    _
    c
    a
    c
    h
    e
    _
    s
    t
    o
    r
    e
    , \
    M
    E
    M
    _
    C
    A
    C
    H
    E
    _
    S
    E
    R
    V
    E
    R
    , M
    E
    M
    _
    C
    A
    C
    H
    E
    _
    O
    P
    T
    I
    O
    N
    S
    R
    a
    i
    l
    s
    .
    c
    a
    c
    h
    e
    .
    w
    r
    i
    t
    e
    (
    '
    f
    o
    o
    '
    , '
    b
    a
    r
    '
    )
    R
    a
    i
    l
    s
    .
    c
    a
    c
    h
    e
    .
    f
    e
    t
    c
    h
    (
    '
    f
    o
    o
    '
    ) #
    =
    > '
    b
    a
    r
    '

    View Slide

  70. Introduce
    caching into our
    Sass rendering

    View Slide

  71. c
    l
    a
    s
    s S
    a
    s
    s
    R
    e
    n
    d
    e
    r
    e
    r
    d
    e
    f i
    n
    i
    t
    i
    a
    l
    i
    z
    e
    (
    t
    e
    m
    p
    l
    a
    t
    e
    , c
    a
    c
    h
    e
    _
    k
    e
    y
    , o
    p
    t
    i
    o
    n
    s
    )
    @
    c
    a
    c
    h
    e
    _
    k
    e
    y = c
    a
    c
    h
    e
    _
    k
    e
    y
    @
    e
    n
    g
    i
    n
    e = S
    a
    s
    s
    :
    :
    E
    n
    g
    i
    n
    e
    .
    n
    e
    w
    (
    t
    e
    m
    p
    l
    a
    t
    e
    , o
    p
    t
    i
    o
    n
    s
    )
    e
    n
    d
    d
    e
    f r
    e
    n
    d
    e
    r
    f
    r
    o
    m
    _
    c
    a
    c
    h
    e { @
    e
    n
    g
    i
    n
    e
    .
    r
    e
    n
    d
    e
    r }
    e
    n
    d
    d
    e
    f c
    a
    c
    h
    e
    d
    ?
    R
    a
    i
    l
    s
    .
    c
    a
    c
    h
    e
    .
    e
    x
    i
    s
    t
    ?
    (
    @
    c
    a
    c
    h
    e
    _
    k
    e
    y
    )
    e
    n
    d
    d
    e
    f g
    e
    t
    _
    c
    a
    c
    h
    e
    d
    _
    c
    s
    s
    R
    a
    i
    l
    s
    .
    c
    a
    c
    h
    e
    .
    f
    e
    t
    c
    h
    (
    @
    c
    a
    c
    h
    e
    _
    k
    e
    y
    )
    e
    n
    d
    p
    r
    i
    v
    a
    t
    e
    d
    e
    f s
    e
    t
    _
    c
    a
    c
    h
    e
    d
    _
    c
    s
    s
    (
    c
    s
    s
    )
    R
    a
    i
    l
    s
    .
    c
    a
    c
    h
    e
    .
    w
    r
    i
    t
    e
    (
    @
    c
    a
    c
    h
    e
    _
    k
    e
    y
    , c
    s
    s
    )
    e
    n
    d
    d
    e
    f f
    r
    o
    m
    _
    c
    a
    c
    h
    e
    (
    &
    w
    r
    i
    t
    e
    _
    b
    l
    o
    c
    k
    )
    g
    e
    t
    _
    c
    a
    c
    h
    e
    d
    _
    c
    s
    s |
    | w
    r
    i
    t
    e
    _
    b
    l
    o
    c
    k
    .
    c
    a
    l
    l
    .
    t
    a
    p { |
    c
    s
    s
    | s
    e
    t
    _
    c
    a
    c
    h
    e
    d
    _
    c
    s
    s
    (
    c
    s
    s
    ) }
    e
    n
    d
    e
    n
    d

    View Slide

  72. Incorporate into
    S
    a
    s
    s
    C
    u
    s
    t
    o
    m
    P
    a
    l
    e
    t
    t
    e

    View Slide

  73. c
    l
    a
    s
    s S
    a
    s
    s
    C
    u
    s
    t
    o
    m
    P
    a
    l
    e
    t
    t
    e
    d
    e
    f i
    n
    i
    t
    i
    a
    l
    i
    z
    e
    (
    c
    o
    l
    o
    r
    )
    @
    c
    o
    l
    o
    r = c
    o
    l
    o
    r
    @
    c
    a
    c
    h
    e
    _
    k
    e
    y = "
    c
    u
    s
    t
    o
    m
    _
    p
    a
    l
    e
    t
    t
    e
    /
    #
    {
    @
    c
    o
    l
    o
    r
    }
    "
    @
    e
    n
    g
    i
    n
    e = S
    a
    s
    s
    R
    e
    n
    d
    e
    r
    e
    r
    .
    n
    e
    w
    (
    T
    E
    M
    P
    L
    A
    T
    E
    , @
    c
    a
    c
    h
    e
    _
    k
    e
    y
    , s
    a
    s
    s
    _
    c
    u
    s
    t
    o
    m
    _
    o
    p
    t
    i
    o
    n
    s
    )
    e
    n
    d
    d
    e
    l
    e
    g
    a
    t
    e :
    r
    e
    n
    d
    e
    r
    , t
    o
    : :
    @
    e
    n
    g
    i
    n
    e
    e
    n
    d

    View Slide

  74. And?

    View Slide

  75. View Slide

  76. What about the
    first render?

    View Slide

  77. Process in the
    background

    View Slide

  78. sidekiq.org

    View Slide

  79. Why Bother?

    View Slide

  80. Free up server thread quickly
    to handle new request

    View Slide

  81. No thread concurrency
    guarantees with MRI

    View Slide

  82. But...

    View Slide

  83. Code complexity

    View Slide

  84. Polling client

    View Slide

  85. Websockets

    View Slide

  86. Failing jobs

    View Slide

  87. Waiting on an
    available worker

    View Slide

  88. Network traffic

    View Slide

  89. Setting up a
    Sidekiq worker

    View Slide

  90. # a
    p
    p
    /
    w
    o
    r
    k
    e
    r
    s
    /
    s
    a
    s
    s
    _
    c
    u
    s
    t
    o
    m
    _
    p
    a
    l
    e
    t
    t
    e
    _
    w
    o
    r
    k
    e
    r
    .
    r
    b
    c
    l
    a
    s
    s S
    a
    s
    s
    C
    u
    s
    t
    o
    m
    P
    a
    l
    e
    t
    t
    e
    W
    o
    r
    k
    e
    r
    i
    n
    c
    l
    u
    d
    e S
    i
    d
    e
    k
    i
    q
    :
    :
    W
    o
    r
    k
    e
    r
    d
    e
    f p
    e
    r
    f
    o
    r
    m
    (
    c
    o
    l
    o
    r
    )
    S
    a
    s
    s
    C
    u
    s
    t
    o
    m
    P
    a
    l
    e
    t
    t
    e
    .
    n
    e
    w
    (
    c
    o
    l
    o
    r
    )
    .
    r
    e
    n
    d
    e
    r
    e
    n
    d
    e
    n
    d
    c
    l
    a
    s
    s S
    a
    s
    s
    C
    u
    s
    t
    o
    m
    P
    a
    l
    e
    t
    t
    e
    d
    e
    f r
    e
    n
    d
    e
    r
    _
    a
    s
    y
    n
    c
    u
    n
    l
    e
    s
    s @
    e
    n
    g
    i
    n
    e
    .
    c
    a
    c
    h
    e
    d
    ?
    S
    a
    s
    s
    C
    u
    s
    t
    o
    m
    P
    a
    l
    e
    t
    t
    e
    W
    o
    r
    k
    e
    r
    .
    p
    e
    f
    o
    r
    m
    _
    a
    s
    y
    n
    c
    (
    @
    c
    o
    l
    o
    r
    )
    e
    n
    d
    @
    c
    a
    c
    h
    e
    _
    k
    e
    y
    e
    n
    d
    e
    n
    d

    View Slide

  91. c
    l
    a
    s
    s S
    a
    s
    s
    R
    e
    n
    d
    e
    r
    e
    r
    d
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  92. What would polling look like?

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  93. Polling

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  94. Polling

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  95. Polling

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  96. Polling

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  97. Polling

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  98. Polling

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  99. Polling

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  100. Polling

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  101. c
    l
    a
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  102. Is this the best
    answer?

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  103. Can refactoring
    simplify our
    Sass?

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  104. YES!

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  105. Identified areas for code
    improvement

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  106. Acceptable render times

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  107. Eliminate need for background
    processing

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  108. Recap

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  109. Reuse Sass style sheets to
    render static and dynamic
    content

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  110. Sass rendering isn't always fast

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  111. Web server performance

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  112. Importance of caching

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  113. Background processing

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  114. Sometimes refactoring is all
    you need

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  115. So what does this mean?

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  116. Things aren't always simple

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  117. We always have to consider
    performance

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  118. Thanks!
    Slides:
    Demo Source:
    Blog:
    sassy-talk.jeremyfairbank.com
    github.com/jfairbank/dynamically-sassy-demos
    blog.jeremyfairbank.com
    [email protected]
    @elpapapollo
    github.com/jfairbank

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