Slide 1
Slide 1 text
PROTOCOL-ORIENTED
PROGRAMMING
IN NETWORKING
ISHKAWA
Slide 2
Slide 2 text
ISHKAWA?
Slide 3
Slide 3 text
OVERVIEW
PROTOCOL-ORIENTED PROGRAMMING IN NETWORKING
1. Wrapping NSURLSession using protocols
2. Generic programming on the protocols
3. Combination with RxSwift
Slide 4
Slide 4 text
TOPIC 1
Wrapping NSURLSession using protocols
To make call-site code simpler
To get responses type-safely
Slide 5
Slide 5 text
GOAL
Slide 6
Slide 6 text
GOAL
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Slide 7
Slide 7 text
GOAL
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The type of result changes depending on the request type
Slide 8
Slide 8 text
WHY PROTOCOL?
1. To associate response type with request type
2. To provide flexible default implementation
Slide 9
Slide 9 text
WHY PROTOCOL?
1. To associate response type with request type
2. To provide flexible default implementation
Slide 10
Slide 10 text
ASSOCIATING RESPONSE TYPE
WITH REQUEST TYPE
p
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Slide 11
Slide 11 text
ASSOCIATING RESPONSE TYPE
WITH REQUEST TYPE
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Slide 12
Slide 12 text
ASSOCIATING RESPONSE TYPE
WITH REQUEST TYPE
l
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t = C
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The type of result changes depending on the request type
Slide 13
Slide 13 text
WHY PROTOCOL?
2. To provide flexible default implementation
1. To associate response type with request type
Slide 14
Slide 14 text
PROVIDING DEFAULT IMPLEMENTATION
PART 1: COMMON CONFIGURATIONS
p
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Slide 15
Slide 15 text
PROVIDING DEFAULT IMPLEMENTATION
PART 2: PROTOCOL FOR JSON DECODING
s
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Slide 16
Slide 16 text
PROVIDING DEFAULT IMPLEMENTATION
PART 2: PROTOCOL FOR JSON DECODING
p
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}
Slide 17
Slide 17 text
PROVIDING DEFAULT IMPLEMENTATION
PART 2: PROTOCOL FOR JSON DECODING
e
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Slide 18
Slide 18 text
PROVIDING DEFAULT IMPLEMENTATION
PART 2: PROTOCOL FOR JSON DECODING
s
t
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t S
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Slide 19
Slide 19 text
WHY PROTOCOL?
1. To associate response type with request type
Simpler and safer call-site
2. To provide flexible default implementation
Documentation-like request definition
Slide 20
Slide 20 text
LINKS
APIKit:
RequestType, Session, etc.
Himotoki:
Decodable, etc.
https://github.com/ishkawa/APIKit
https://github.com/ikesyo/Himotoki
Slide 21
Slide 21 text
TOPIC 2
Practical example of generic programming on protocols
Example: Pagination
Slide 22
Slide 22 text
PAGINATION REQUEST
c
u
r
l -
v h
t
t
p
s
:
/
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g
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?
q
=
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&
p
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e
=
1
Slide 23
Slide 23 text
PAGINATION REQUEST
p
r
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t
o
c
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l P
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t
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p
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> S
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l
f
}
Slide 24
Slide 24 text
PAGINATION RESPONSE
H
T
T
P
/
1
.
1 2
0
0 O
K
S
e
r
v
e
r
: G
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Slide 25
Slide 25 text
PAGINATION RESPONSE
p
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t
o
c
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l P
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g
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a
t
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n
R
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}
Slide 26
Slide 26 text
PAGINATION CLIENT
c
l
a
s
s P
a
g
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Slide 27
Slide 27 text
PAGINATION CLIENT
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Slide 28
Slide 28 text
GENERIC PROGRAMMING ON PROTOCOLS
More type constraints,
more detailed implementation
Slide 29
Slide 29 text
TOPIC 3
Advanced example with reactive streams
Slide 30
Slide 30 text
RXPAGINATION
Slide 31
Slide 31 text
PAGINATION VM WITH RXSWIFT
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Slide 32
Slide 32 text
LIVE!
Slide 33
Slide 33 text
STEPS TO IMPLEMENT PAGINATION
Give a base request to ViewModel
Bind input and output streams
Slide 34
Slide 34 text
CONCLUSION
PROTOCOL-ORIENTED IN NETWORKING
1. Protocol is a good choice for abstraction of networking
2. More type constraints, more detailed implementation
3. Abstraction of event stream is also nice
Slide 35
Slide 35 text
TRY! POP