For just over a year, Swift has been available as a formal release on Linux and frameworks like Kitura and Vapor have made it possible to build mobile backends and web applications on the server. Running Server Swift is however not your own option for becoming a fullstack engineer and building backends in Swift. Amazon, Microsoft, Google, IBM and others are all also providing the ability to run Serverless (aka Lambdas or Functions), with some of those supporting the use of Swift. This session will introduce you to Serverless Swift, highlight how it compares to Server Swift and show you some applications that have been built with Server(less) Swift.

1. Server(less) Swift
with Kitura and OpenWhisk
Chris Bailey
@Chris__Bailey
FrenchKit 2017
September 22nd

2. 2
(less) SwiftServer

3. 3
SwiftServer

4. 4
FullStack
0
17.5
35
52.5
70
FullStack
Backend
Frontend
11.9
24.4
63.7

5. 5
FullStack
0
17.5
35
52.5
70
FullStack
Backend
Frontend
11.9
24.4
63.7
0
40
80
120
160
141.5
16.2
4.34
Fast

6. 6
FullStack
0
17.5
35
52.5
70
FullStack
Backend
Frontend
11.9
24.4
63.7
0
40
80
120
160
141.5
16.2
4.34
Fast
0
15
30
45
60
50.2
31.3
29.9
11.7
Efficient

7. 7
iOS APP
Hosted Services
GATEWAY
PUBLIC NETWORK CLOUD NETWORK
SWAGGER
DATA
PUSH ANALYTICS
DEVOPS AVAILABILITY MONITORINGSCALING
SOCIAL
COGNATIVE
AUTH
WEB APP

8. 8

9. import Kitura
import SwiftyJSON
9

10. import Kitura
import SwiftyJSON
router.all("/*", middleware: BodyParser())
router.post(path, handler: handleCreate)
10

11. import Kitura
import SwiftyJSON
router.all("/*", middleware: BodyParser())
router.post(path, handler: handleCreate)
func handleCreate(request: RouterRequest, response: RouterResponse,
next: @escaping () -> Void) {
}
11

12. import Kitura
import SwiftyJSON
router.all("/*", middleware: BodyParser())
router.post(path, handler: handleCreate)
func handleCreate(request: RouterRequest, response: RouterResponse,
next: @escaping () -> Void) {
guard case .json(let json)? = request.body else {
response.status(.badRequest)
response.send(json: JSON([ "error": "Request not JSON" ]))
return next()
}
}
12

13. import Kitura
import SwiftyJSON
router.all("/*", middleware: BodyParser())
router.post(path, handler: handleCreate)
func handleCreate(request: RouterRequest, response: RouterResponse,
next: @escaping () -> Void) {
guard case .json(let json)? = request.body else {
response.status(.badRequest)
response.send(json: JSON([ "error": "Request not JSON" ]))
return next()
}
let name = json["name"].string
let rating = json[“rating"].number
// etc
// etc
}
13

14. import Kitura
import SwiftyJSON
router.all("/*", middleware: BodyParser())
router.post(path, handler: handleCreate)
func handleCreate(request: RouterRequest, response: RouterResponse,
next: @escaping () -> Void) {
guard case .json(let json)? = request.body else {
response.status(.badRequest)
response.send(json: JSON([ "error": "Request not JSON" ]))
return next()
}
let name = json["name"].string
let rating = json[“rating"].number
// etc
// etc
next()
}
14

15. 15
Decreasing concern (and control)
over stack implementation
Increasingfocusonbusinesslogic
IaaS

16. 16
Decreasing concern (and control)
over stack implementation
Increasingfocusonbusinesslogic
IaaS

17. 17
Decreasing concern (and control)
over stack implementation
Increasingfocusonbusinesslogic
IaaS
CaaS

18. 18
Decreasing concern (and control)
over stack implementation
Increasingfocusonbusinesslogic
IaaS
CaaS
PaaS

19. 19
Decreasing concern (and control)
over stack implementation
Increasingfocusonbusinesslogic
IaaS
CaaS
PaaS
?

20. 20
Decreasing concern (and control)
over stack implementation
Increasingfocusonbusinesslogic
IaaS
CaaS
PaaS
? Serverless
Serverless

21. 21
Functions-as-a-Service

22. 22
PaaS FaaS
OpenWhisk

23. 23
PaaS
Write application centric business
logic.
FaaS
Write event-driven business logic.
OpenWhisk

24. 24
PaaS
Write application centric business
logic.
Treat compute resources as utilities.
FaaS
Write event-driven business logic.
Treat compute resources as utilities.
OpenWhisk

25. 25
PaaS
Write application centric business
logic.
Treat compute resources as utilities.
Provides scaling, resilience and
availability
FaaS
Write event-driven business logic.
Treat compute resources as utilities.
Provides scaling, resilience and
availability
OpenWhisk

26. 26
“If your PaaS can efficiently start instances in 20ms
that run for half a second, then call it serverless.”
- Adrian Cockcroft

27. 27

28. 28

29. 29
func main(args: [String:Any]) -> [String:Any] {
// Action code
// goes here
return [ “result" : "value" ]
}

30. 30
func main(args: [String:Any]) -> [String:Any] {
// Action code
// goes here
return [ “result" : "value" ]
}
Entry Point

31. 31
func main(args: [String:Any]) -> [String:Any] {
// Action code
// goes here
return [ “result" : "value" ]
}
Entry Point Event Parameters

32. 32
func main(args: [String:Any]) -> [String:Any] {
// Action code
// goes here
return [ “result" : "value" ]
}
Entry Point Event Parameters
Result

33. 33
func main(args: [String:Any]) -> [String:Any] {
}

34. 34
func main(args: [String:Any]) -> [String:Any] {
if let name = args["name"] as? String {
}
}

35. 35
func main(args: [String:Any]) -> [String:Any] {
if let name = args["name"] as? String {
return [ "greeting" : "Hello (name)!" ]
}
}

36. 36
func main(args: [String:Any]) -> [String:Any] {
if let name = args["name"] as? String {
return [ "greeting" : "Hello (name)!" ]
} else {
return [ "greeting" : "Hello stranger!" ]
}
}

37. 37
$ git clone https://github.com/openwhisk/openwhisk.git
Get OpenWhisk

38. 38
$ git clone https://github.com/openwhisk/openwhisk.git
$ cd openwhisk/tools/vagrant
$ vagrant up
Get OpenWhisk

39. 39
$ git clone https://github.com/openwhisk/openwhisk.git
$ cd openwhisk/tools/vagrant
$ vagrant up
Get OpenWhisk
Start OpenWhisk
(in a Linux VM)

40. 40

41. $ wsk action create hello main.swift
41

42. $ wsk action create hello main.swift
42
Create
Action

43. $ wsk action create hello main.swift
43
Create
Action Called

44. $ wsk action create hello main.swift
44
Create
Action Called From

45. $ wsk action create hello main.swift
ok: created action hello
45
Create
Action Called From

46. $ wsk action create hello main.swift
ok: created action hello
$ wsk action list
46
Create
Action Called From

47. $ wsk action create hello main.swift
ok: created action hello
$ wsk action list
actions
hello private
47
Create
Action Called From

48. $ wsk action create hello main.swift
ok: created action hello
$ wsk action list
actions
hello private
48
Create
Action
Our Action
Called From

49. $ wsk action invoke --result hello --param name World
49

50. $ wsk action invoke --result hello --param name World
50
Invoke
Action

51. $ wsk action invoke --result hello --param name World
51
Invoke
Action Called

52. $ wsk action invoke --result hello --param name World
52
Invoke
Action Called
With
Parameters

53. $ wsk action invoke --result hello --param name World
{
“greeting" : “Hello World!”
}
53
Invoke
Action Called
With
Parameters

54. 54
T
Triggers
• Database update
• IoT sensor activation
• GitHub hook
• Slack notification
• REST request
T

55. 55
T A
Triggers
• Database update
• IoT sensor activation
• GitHub hook
• Slack notification
• REST request
Actions
• Your code
• Single task
• Any language
• Docker binary
• Returns JSON
AT

56. 56
T A R
Triggers
• Database update
• IoT sensor activation
• GitHub hook
• Slack notification
• REST request
Actions
• Your code
• Single task
• Any language
• Docker binary
• Returns JSON
Rules
• Link Triggers to
Actions
• Create sequences
• Many to many maps
become possible
ATR :=

57. 57
T A R
Triggers
• Database update
• IoT sensor activation
• GitHub hook
• Slack notification
• REST request
Actions
• Your code
• Single task
• Any language
• Docker binary
• Returns JSON
Rules
• Link Triggers to
Actions
• Create sequences
• Many to many maps
become possible
ATR A
A1
A2
A3
:= + +:=

58. 58
T A R P
Triggers
• Database update
• IoT sensor activation
• GitHub hook
• Slack notification
• REST request
Actions
• Your code
• Single task
• Any language
• Docker binary
• Returns JSON
Rules
• Link Triggers to
Actions
• Create sequences
• Many to many maps
become possible
Packages
• Collection of triggers
and actions
ATR A
A1
A2
A3
AB
A2
A1
A4TR
:=
:=
+
+
+
+
:=
:=

59. $ wsk api create /hello get hello —response-type json
59

60. $ wsk api create /hello get hello —response-type json
60
Create
API

61. $ wsk api create /hello get hello —response-type json
61
Create
API
REST
Route Method

62. $ wsk api create /hello get hello —response-type json
62
Create
API
REST
Route Method
From
Action

63. $ wsk api create /hello get hello —response-type json
ok: created API /hello GET for action /_/hello
https://${APIHOST}:9001/api/21ef035/hello
63
Create
API
REST
Route Method
From
Action

64. $ wsk api create /hello get hello —response-type json
ok: created API /hello GET for action /_/hello
https://${APIHOST}:9001/api/21ef035/hello
$ curl https://${APIHOST}:9001/api/21ef035/hello?
name=World
64
Create
API
REST
Route Method
From
Action

65. 65

66. 66
• Mobile client SDK for iOS and watchOS.
• Fire remote triggers and invoke remote
actions.
• Swift 3, iOS9+ and watchOS 3.
• Install by using CocoaPods, Carthage,
Swift Package Manager, or from the
source directory.
https://github.com/apache/incubator-openwhisk-client-swift

67. var params = [String: String]()
params["payload"] = "Hello"
67

68. var params = [String: String]()
params["payload"] = "Hello"
do {
try whisk.invokeAction(name: "hello", parameters: params,
hasResult: true, callback:
{(reply, error) -> Void in
})
} catch {
print("Error (error)")
}
68

69. var params = [String: String]()
params["payload"] = "Hello"
do {
try whisk.invokeAction(name: "hello", parameters: params,
hasResult: true, callback:
{(reply, error) -> Void in
if let error = error {
print("Error invoking action (error.localizedDescription)")
} else {
var result = reply["result"]
print("Got result (result)")
}
})
} catch {
print("Error (error)")
}
69

70. 70
Weather Gods

71. Weather Gods
• Premium app from Meyume Ltd.
• Offers a rich interactive experience
unlike other weather apps.
• Sources high quality weather data from
multiple providers including The
Weather Company.
• Provides weather notifications:
• type (rain, snow etc.)
• schedule (evening, morning, or live)
• options (e.g. only notify about heavy
rain).
71

72. 72
3-minute
alarm
Group
scanner
Weather
collector
Wind
scanner
Rain
scanner
Fog
scanner
Alarm
trigger
Alarm
trigger
Alarm
trigger
Send
push
Send
push
Send
push
Push
notification
service

73. 73
BluePic

74. 74
BluePic
• Sample app from IBM
• iOS and Web front ends
• Provides photo sharing
• Adds image recognition and weather
data to the photo
• Provides notifications to users
• Social sharing
• Updates to data
https://github.com/IBM/BluePic

75. 75
PUBLIC NETWORK CLOUD NETWORK
iOS APP
WEB APP

76. 76
PUBLIC NETWORK CLOUD NETWORK
iOS APP
WEB APP

77. 77
PUBLIC NETWORK CLOUD NETWORK
iOS APP
WEB APP

78. 78
PUBLIC NETWORK CLOUD NETWORK
iOS APP
WEB APP

79. 79
PUBLIC NETWORK CLOUD NETWORK
iOS APP
WEB APP

80. 80
PUBLIC NETWORK CLOUD NETWORK
iOS APP
WEB APP

81. 81
PUBLIC NETWORK CLOUD NETWORK
iOS APP
WEB APP

82. 82
PUBLIC NETWORK CLOUD NETWORK
iOS APP
WEB APP

83. 83
Decreasing concern (and control)
over stack implementation
Increasingfocusonbusinesslogic

84. 84
Decreasing concern (and control)
over stack implementation
Increasingfocusonbusinesslogic
Server
Serverless