End-to-end: Building a Web Service in Swift (MCE 2016)

Now that Swift is Open Source, Apple has created a new range of
possibilities. You can now take your existing knowledge, code and
apply them to web application development. I'm going to show you
how you can reuse existing skills to build and deploy your first
web service in Swift.

Transcript

1. End-to-end:
   Building a Web Service in Swift
   

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2. Who am I?
   

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4. How many of you
   have build web
   services or APIs?
   

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5. What is a web
   service?
   

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6. Why Swift on
   Server?
   

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7. Swift
   

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8. Why do many use scripting
   languages for the web?
   

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10. Code Sharing
    

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11. Accessible to
    mobile developers
    

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12. Performance
    

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13. Performance Graph
    Server | Language | request/sec | Comparison
    ---------|----------|-------------|------------
    Curassow | Swift | 7715.83 |
    Gunicorn | Python | 5269.49 | 32% less req/s than Curassow
    Unicorn | Ruby | 4253.33 | 45% less req/s Curassow
    

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15. How
    

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16. /// Format the given string for presentation
    func formatForDate(date: NSDate) -> String {
    let formatter = NSDateFormatter()
    formatter.formatString = "DD MM yyyy"
    return formatter.stringForDate(date)
    }
    

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17. func viewDidLoad() {
    super.viewDidLoad()
    // Using our date formatting in iOS
    button.title = formatForDate(NSDate())
    }
    

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18. import Frank
    get {
    return formatForDate(NSDate())
    }
    

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19. $ swift build
    $ .build/debug/date-example
    

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20. $ curl http://localhost:8000/
    21 04 2016
    

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22. Where to begin
    

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23. Life-cycle
    

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24. Planning
    

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25. https://apiblueprint.org/
    

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26. # Render [POST /render]
    + Request (application/json)
    {
    "template": "Hello {{ name }}",
    "context": {
    "name": "Kyle"
    }
    }
    

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27. # Preview [POST /preview]
    + Response 200
    Hello Kyle
    

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28. Development
    

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29. Swift Package
    Manager
    

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30. Swift 2 vs Swift 3
    

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31. swiftenv
    https://swiftenv.fuller.li/
    

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32. $ swiftenv install 2.2
    

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33. $ swiftenv local DEVELOPMENT-SNAPSHOT-2016-02-08-a
    

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34. $ cat .swift-version
    DEVELOPMENT-SNAPSHOT-2016-02-08-a
    

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35. $ swift --version
    Apple Swift version 2.2
    $ cd Stencil
    $ swift --version
    Apple Swift version 3.0-dev
    

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36. Web Frameworks
    

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37. Separation of
    Concerns
    Web Servers / Web Frameworks
    

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38. Frank
    

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39. get("users", "kyle", "followers") { request in
    }
    

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40. get("users", *) { (request, username: String) in
    }
    

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41. Custom Parameter Type
    enum Status {
    case Open
    case Closed
    }
    

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42. Custom Parameter Type
    extension Status : ParameterConvertible {
    init?(parser: ParameterParser) {
    switch parser.shift() ?? "" {
    case "open":
    self = .Open
    case "closed":
    self = .Closed
    default:
    return nil
    }
    }
    }
    

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43. get("issues", *) { (request, status: Status) in
    return "Issues using status: \(status)"
    }
    

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44. Swift Safety
    get("/users/:username") { (request, params) in
    let username = params["username"]!
    return "Hello \(username)"
    }
    

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46. let router = Router()
    router.get("/users/:username") { request, response, next in
    let username = request.params["username"] ?? "(nil)"
    try response.status(HttpStatusCode.OK).send("Hello \(username)")
    }
    let server = HttpServer.listen(8090, delegate: router)
    Server.run()
    

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47. Web Server
    

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48. Curassow
    https://curassow.fuller.li/
    

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49. $ curassow --workers 5
    [INFO] Listening at http://localhost:8080 (65416)
    [INFO] Booting worker process with pid: 65417
    [INFO] Booting worker process with pid: 65418
    [INFO] Booting worker process with pid: 65419
    [INFO] Booting worker process with pid: 65420
    [INFO] Booting worker process with pid: 65421
    

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50. Standards
    

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51. Learn from others' mistakes
    

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52. Tight Coupling
    

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53. Nest
    https://github.com/nestproject/Nest
    

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54. func application(request: RequestType) -> ResponseType {
    return Response(.Ok, body: "Hello World")
    }
    

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55. Nest Enhancement
    Proposals
    

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56. Template Languages
    

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57. Stencil
    http://stencil.fuller.li/
    

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58. There are {{ articles.count }} articles.
    {% for article in articles %}
    - {{ article.title }} by {{ article.author }}.
    {% endfor %}
    

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59. Users
    
    {% for user in users %}
    {{ user }}
    {% endfor %}
    
    

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60. Persistence
    

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61. ORM
    Object Relational Mapping
    

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62. QueryKit
    http://querykit.org/
    let user = User.queryset(context)
    .filter { $0.name == "Kyle" }
    .orderBy {}
    .first
    

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64. Redis (Redbird)
    let client = try Redbird(config: ...)
    // Set name to MCE
    try client.command("SET", params: ["name", "MCE"])
    // Get the name
    try client.command("GET", params: ["name"])
    

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65. PostgreSQL
    let connection = Connection(host: "localhost", databaseName: "db")
    try connection.open()
    let usernames = try connection.execute("SELECT username FROM users").map {
    try $0.data("username")
    }
    

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66. Testing
    

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67. Spectre
    http://spectre.fuller.li/
    

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68. describe("a person") {
    let person = Person(name: "Kyle")
    $0.it("has a name") {
    try expect(person.name) == "Kyle"
    }
    $0.it("returns the name as description") {
    try expect(person.description) == "Kyle"
    }
    }
    

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70. XCTest
    

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71. class PersonTests: XCTestCase {
    let person = Person(name: "Kyle")
    func testPersonName() {
    XCTAssertEqual(person.name, "Kyle")
    }
    func testPersonDescription() {
    XCTAssertEqual(person.description, "Kyle")
    }
    }
    

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72. extension PersonTests: XCTestCaseProvider {
    var allTests : [(String, () throws -> Void)] {
    return [
    ("testPersonName", testPersonName),
    ("testPersonDescription", testPersonDescription),
    ]
    }
    }
    XCTMain([
    PersonTests(),
    ])
    

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73. Dredd
    https://github.com/apiaryio/dredd
    

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74. Swift on Travis CI
    https://swiftenv.fuller.li/en/latest/
    integrations/travis-ci.html
    

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75. Deployment
    

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76. https://github.com/kylef/heroku-buildpack-swift
    

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77. $ cat Package.swift
    import PackageDescription
    let package = Package(
    name: "Hello",
    dependencies: [
    .Package(url: "https://github.com/nestproject/Frank.git",
    majorVersion: 0, minor: 3),
    ]
    )
    

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78. $ cat Sources/main.swift
    import Frank
    get { _ in
    return "Hello World"
    }
    get(*) { (_, username: String) in
    return "Hello \(username)"
    }
    

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79. $ cat .swift-version
    2.2-SNAPSHOT-2016-01-11-a
    

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80. $ swift build
    $ .build/debug/Hello
    [INFO] Listening at http://0.0.0.0:8000 (48827)
    [INFO] Booting worker process with pid: 48828
    

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81. $ cat Procfile
    web: Hello
    

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82. $ heroku create --buildpack https://github.com/kylef/heroku-buildpack-swift.git
    $ git push heroku master
    remote: -----> Swift app detected
    remote: -----> Installing 2.2-SNAPSHOT-2016-01-11-a
    remote: -----> Installing clang-3.7.0
    remote: -----> Building Package
    remote: -----> Copying binaries to 'bin'
    

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85. Manual Deployment
    

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86. Monitoring
    

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87. Logging
    

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88. print("ERROR: Connection to database failed \(error)")
    

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89. Papertrail
    

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92. What's Next?
    

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93. Swift 3
    

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94. Stability
    

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95. Maturity
    

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96. What have we covered today
    • Why you might want to build a web application
    in Swift
    • How you can design, develop, deploy Swift web
    applications
    

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97. kylefuller
    https://fuller.li/talks
    

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