This document contains the transcript of a presentation by Chris Heilmann on web development. Some of the key points discussed include: - The benefits of progressive enhancement and using HTML, CSS, and JavaScript together to build robust and accessible websites. - How limitations in early design can foster creativity. - The importance of error handling and defensive coding practices. - Embracing new technologies like Service Workers and Manifests to build Progressive Web Apps. - Rethinking the idea that JavaScript is unreliable and should not be depended on, as modern browsers have made it a capable tool.

1. Chris Heilmann @codepo8, DrupalJam, May 2017

2. Of innovation and impatience
Chris Heilmann @codepo8, Future Decoded, London, Nov 2015
CHRIS HEILMANN
@CODEPO8

3. codepo8.github.io/logo-o-matic
codepo8.github.io/canvas-images-and-pixels
Pixels are my thing… :)

4. We all know this
character, right?
https://en.wikipedia.org/wiki/Mario#Concept_and_creation

5. But do you know
why it looks like it
does?
https://en.wikipedia.org/wiki/Mario#Concept_and_creation

6. Red and Blue offered the
best contrast to the skin,
boots and the game
background.
https://en.wikipedia.org/wiki/Mario#Concept_and_creation

7. The cap meant there was
no need to worry about
hair style, eyebrows and
forehead.
(There were also not enough
pixels for waving hair when
falling down a hole)

8. The large nose and
moustache made it
possible to avoid a mouth
and facial expressions.

9. Design by limitations.
!

10. Design by lack of definition.
🌎🕸

11. Flexibility and forgiveness…
💧 HTML and CSS are fault tolerant…

12. Knives, bees and footguns…
🦂 JavaScript is not fault tolerant

13. With HTML and CSS you’re
relying on the user agent to
do the right thing…🙁

14. Using JavaScript, you have a
means to test if what you’re
trying to do succeeded…✅

15. Predicting things is tough…
🔮

16. That’s why progressive
enhancement was a great
idea to solve this issue…

17. But is it still enough?
🔬

18. And what does it mean?
🤔

19. JavaScript can’t be trusted and
can be turned off.
💣

20. Everybody has JavaScript, and
we can do everything with it?
🔨

21. !

22. Story time…🐷*3🐺+🏠+🌳

23. https://a-k-apart.com/

24. Excellent, let’s do this!
https://codepo8.github.io/10kb-CSS-colour-game/

25. That was fun…
😎 Written on a plane, offline and in
roughly two hours
😎 Works on desktop and mobile,
independent of input and is
responsive
😎 All in all < 8 kb with the biggest
part being icons
https://codepo8.github.io/10kb-CSS-colour-game/

26. Well done, Chris!
https://www.google.com/patents/US4608967

27. Here’s the source… …Luke?

28. The structure was not hard…
😎 Have an array of all the possible colours.
😎 Get a random cut of n elements, display them as a list; store the name of the colour
as a data attribute
😎 Get one item of the list as the colour to match, show its name.
😎 Use event delegation on the list to add one click handler (also allows for keyboard)
😎 Compare the data attribute of the target of the event with the colour to match
😎 If true, display a new random list
😎 If false, decrease the possible moves counter
😎 If no more moves left, show game over
💩 Only issue: there is no array_rand()

29. Computers and smartphones are
powerful.
Browsers can do a lot and are open to
feedback.
JavaScript is flexible and has evolved.
CSS has become amazing.
Developer tools in browsers give us great
debugging and even design capabilities
😍
🦄
🎉

30. The beauty of HTML, CSS and JS…
😍 All is contained in one package
😍 Everything is running on the end users
environments
😍 You use what the OS and the hardware gives
you. It can be a web site or an app,
depending on who runs it where
😍 You wouldn’t even need ServiceWorker to
make this work offline - inlining everything
would be enough
📦

31. Then I read the contest
guidelines…
😟

32. https://a-k-apart.com/faq http://stateofjs.com/

33. I FAQed up…
😭

34. Should I try to make this
a NodeJS, universal,
functional, gluten-free…🤔

35. Sod it, I know PHP…
🤓

36. New, more sturdy structure…
😎 Write a PHP API with the named colours as the content
😎 Use array_rand() to get a cut of that, pick one as the one to match
😎 Write out a list of buttons with the same name and the colour as the value.
😎 If the colour matches the button that was clicked, get a new list
😎 If the colour doesn’t match, decrease the amount of moves and show the list again.
😠 Oh, crap…

37. As we don’t keep the
state of the game in the
browser, I need to
maintain the random
array in between
reloads…
👜

38. The amount is not much,
but you better make sure
that there is no way to
inject code to the server.
🚨

40. Constant vigilance,
Harry…

41. Now it works without JS, let’s add some…
😎 Load the API content with AJAX
🤔 Repeat the rest of the functionality client-side, or do
a lot of unnecessary server roundtrips…
🍕

42. The better, sturdier, more webby version
🤔 Almost same amount of
JavaScript content
🤔 Doesn’t work offline, unless
we also create a different
API
🤔 But it does work with
JavaScript disabled.
😨 It also allows bad people
to inject code unless we
are very vigilant in keeping
our backend secure.

43. How about some heresy?
😯

44. The “JavaScript not available”
argument is largely bogus
and is holding back the web!
➡
🎤

45. The “JavaScript is flaky and
will break” argument is very
much alive and will always be
that way…
🚧

46. Until the first successful load,
you have no JavaScript
functionality. That is a fact.B

47. We call this “programming”
C

48. 🖥→💻→📱
Evolution is happening around us…
…and user numbers are shifting.

49. This means that new error
cases become much more
important than “JavaScript is
not available”
⚠

50. ✏ Small initial payload
✏ Form factor supporting content
✏ Form factor supporting interfaces
✏ Offline/Flaky connection support
✏ Taking advantage of the power of
the end user device
✏ Avoiding interaction latency
❤📲

51. This is achievable using
HTML, JavaScript and CSS,
but it is much harder - if
not impossible - without
client side scripting.
👷

52. Which is annoying, as the
HTML5 revolution
promised a move from
documents to apps…

53. The problem is that eight
years after the proposal
and five years after
HTML5’s “last call”, there
are still many basic support
issues…
😦

54. https://vimeo.com/176453149
Monica Dinculescu < INPUT >
HTML Special, CSS Day

55. https://www.filamentgroup.com/lab/type-number.html

56. And the bad people of the
internet don’t stop abusing
old technology either…💀

57. In UGC, we can’t have nice things…
https://mathiasbynens.github.io/rel-noopener/
https://medium.com/@jitbit/target-blank-the-most-underestimated-vulnerability-ever-96e328301f4c#.mjuw7q3cf

58. Keep users on this page…
https://mathiasbynens.github.io/rel-noopener/
https://medium.com/@jitbit/target-blank-the-most-underestimated-vulnerability-ever-96e328301f4c#.mjuw7q3cf
🔓💩

59. Fix for newer browsers…
https://mathiasbynens.github.io/rel-noopener/
https://medium.com/@jitbit/target-blank-the-most-underestimated-vulnerability-ever-96e328301f4c#.mjuw7q3cf

60. Fix for all browsers…
https://mathiasbynens.github.io/rel-noopener/
https://medium.com/@jitbit/target-blank-the-most-underestimated-vulnerability-ever-96e328301f4c#.mjuw7q3cf

61. Almost…
Listen for the click event and prevent the default
browser behavior of opening a new tab. Inject a
hidden iframe that opens the new tab, then
immediately remove the iframe.“
https://github.com/danielstjules/blankshield

62. Our solutions should have
excellent error handling
instead of automatic
tolerance.
👌

63. And they should be great
solutions and not just
“good enough without
breaking”.
https://twitter.com/dieni/status/767589581046841344

64. Non-defensive coding is a problem…

65. We all make mistakes and errors happen…

66. There is a culture of “let’s
use whatever until it works”
😐

67. Standing on the shoulders of… …people?

68. http://status.npmjs.org/incidents/dw8cr1lwxkcr

69. http://status.npmjs.org/incidents/dw8cr1lwxkcr

70. http://status.npmjs.org/incidents/dw8cr1lwxkcr
Better be safe and require()…
More detail: the "fs" package is a non-functional
package. It simply logs the word "I am fs" and exits.
There is no reason it should be included in any
modules. However, something like 1000 packages *do*
mistakenly depend on "fs", probably because they were
trying to use a built-in node module called "fs".

71. This is not a JavaScript thing…

72. We have a lot of messy
solutions, and we keep
building more tools to undo
what clogs up the web.

73. Best practices can help with
that, but only when they
apply to the people who
build things and when they
solve current issues and
needs…

74. What about older browsers?

75. What about extreme
environment browsers?

76. These are valid concerns,
but edge cases. And
shouldn’t be used as a
punishment scenario.
🗞

77. What about accessibility, eh?
♿

78. Used sensibly, JavaScript is an
accessibility benefit.
Sometimes the only way to
make things accessible. ARIA
is not magic.
🕹

79. https://codepo8.github.io/gridnav/

80. It is more important for us
to get a grip on the overall
quality of the web and our
code…
🏅

81. Using
instead of a URL or using a
button is not JavaScript’s fault.
It is a bad idea and practice -
probably copy & paste.
💩
<a href="javascript:void(0)">

82. Instead of bashing bad use
of JavaScript, let’s embrace
and scrutinise new ideas like
components and paradigms
like functional programming.
🔎

83. There is a very cool thing
happening right now…
😃

84. Service Worker & PWAs
https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API
🔧 🦄

85. Making the game an App: Manifest
App Manifest (manifest.json)
Using a manifest, the game is
recognised by OS and search engines
as an installable app

86. Service Worker (sw.js)
Using ServiceWorker to cache content
locally so the game can be played
offline.
Making the game an App: Service Worker

87. Making the game an App: Service Worker
Service Worker (sw.js)
Using ServiceWorker to cache content
locally so the game can be played
offline.

88. ✅ Create and publish as much content
independent of JavaScript as you can
✅ JavaScript can make things much more
enjoyable.
✅ Some things are just not worth while to
implement without.
✅ Use JavaScript to benefit from the user’s
hardware
✅ Spend more time building great
interfaces, less time relying on what is
there and can’t break - in many cases it
is disappointing.
It is time to re-
think our best
practice for the
web approach…

89. 🙂 You don’t rely on automatic fixes.
JavaScript breaks and it is painful. It
allows us to analyse what went wrong.
🙂 Tooling is great - we detailed insights
into what happened when
🙂 We take responsibility of the interface. It
is our job to make it happen - not
browser makers to agree and find a
consensus
🙂 We have full control over what gets
loaded when, cached where and
rendered when.
Benefits of an “It’s
OK to rely on JS
for this”
approach…

90. ⚠ We shouldn’t hide functionality in
magical abstractions. A product that
relies on the availability and maintenance
of a framework is not a script
dependency - it is a support issue.
⚠ Just because we can do everything in
JavaScript, doesn’t mean we have to. Use
it when HTML is not good enough or too
broken to rely on.
⚠ While the client is powerful, it is also
unknown. A lot more can be done on
the server - and in JavaScript.
Dangers to be
aware of…

91. Important
considerations
independent of
technology used…
💣 Shit happens! Spend more time in
creating sensible error messaging and
fallbacks, spend less time in trying to
predict every possible error
💣 Slowness kills - our solutions must load
fast what is needed and enhance when
they can. They also need to be snappy.
💣 Offline and flaky is the norm - avoid
network dependency as much as you
can
💣 Security is paramount. A hacked
server sending out malware or spam is
worse than an app that needs a
restart…

92. We have to stop thinking in
binaries, and consider writing
great, secure and failure-
aware solutions using each
technology to its strengths.
🐝

93. Mario evolved - so can the web…

94. CHRIS HEILMANN
@CODEPO8
CHRISTIANHEILMANN.COM
THANKS!