어*랙트의 경우

1. API
*

2. Devjelly
*

3. * !

4. *
SNS **
:)

5. * ** **

6. *
!

7. ** URL
!

8. * 404
URL
onerror !

9. <img
src="http://instarstar.com/some.jpeg"
onerror="http://notfound.com/image.jpg"
alt=" "
/>

10. *
!

11. - -

12. !!

13. 404
!

14. * .

15. *
!

16. .

17. onerror
!

18. , API
URL !

19. !

20. !

21. URL
!

22. ?!! !!

23. **
!

24. **
!
API !!

25. ->
->
! ( )

26. ?!

27. !

28. xhr.request(“GET”, url)

29. = ..

30. !

31. …

32. !

33. ..?

34. !

35. !
!

36. .. .. …

37. .. ..
.. !! !!

39. ,
50
!
??

40. ,
!

41. 50 !

42. 2.5 !

43. !!!!
!

44. .

45. .

46. ..

47. 1.

48. 2.

49. 3.

50. = .

51. CS
2

52. ..

53. ..

54. *

55. ->
.

56. !

57. ..

58. ..
DOM IO .

59. 10 10 , 20 20

60. …

61. ..
~~

62. ..

63. ?

64. ?

65. !

66. !

67. =
!

68. …?

69. !

70. HTTP Method

71. GET, POST, PUT, DELETE

72. HEAD .

73. HEAD HEADER

74. GET

75. HEAD

76. !!!

77. 200
400 !

78. !

79. ?

80. HEAD GET

81. 100kB * 500
50MB

82. HEAD 100B * 500
50kB

83. 50MB, 50kB

84. 50000000B
>>>>>>>>>>>>>>>>>>>
50000B

85. 500 50kB !
!

86. !
MDN ..

88. …

89. !

91. TTFB(Time to first byte)
,

92. .
,

93. *
! ( )

95. 0. API ,
API
.

96. 1. API
.

97. 2.
IO .
..

98. 3. Resource
GET ,
HEAD
.

99. .

100. await Promise.all([…])
IO
!

101. - -