Merge pull request #244 from DP-3T/feature/travel

Add parameter for international key exchange

CHANGELOG.md

@@ -1,7 +1,10 @@
 # Changelog for DP3T-SDK iOS
 
+## Next version
+- Add support for international key exchange with parameter 'federationGateway'
+
 ## Version 2.1.0 (21.12.2020)
-- Add support for iOS 12.5 
+- Add support for iOS 12.5
 - Fix timeshift detection
 
 ## Version 2.0.0 (29.10.2020)

README.md

@@ -45,16 +45,17 @@ Included in this repository is a Calibration App that can run, debug and test th
 ### Initialization
 Name | Description | Function Name
 ---- | ----------- | -------------
-init | Initializes the SDK and configures it | `initialize(applicationDescriptor:urlSession:backgroundHandler)` 
+init | Initializes the SDK and configures it | `initialize(applicationDescriptor:urlSession:backgroundHandler:federationGateway)` 
 
-### Methods 
-Name | Description | Function Name
+### Methods & Properties
+Name | Description | Function/Variable Name
 ---- | ----------- | -------------
 startTracing | Starts EN tracing | `func startTracing(completionHandler:)` 
 stopTracing | Stops EN tracing | `func stopTracing(completionHandler:)` 
 sync | Pro-actively triggers sync with backend to refresh exposed list | `func sync(callback:)` 
 status | Returns a TracingState-Object describing the current state. This contains:<br/>- `numberOfHandshakes` : `Int` <br /> - `trackingState` : `TrackingState` <br /> - `lastSync` : `Date` <br /> - `infectionStatus`:`InfectionStatus`<br /> - `backgroundRefreshState`:`UIBackgroundRefreshStatus ` | `func status(callback:)` 
-iWasExposed | This method must be called upon positive test. | `func iWasExposed(onset:authentication:isFakeRequest:callback:)` 
+iWasExposed | This method must be called upon positive test. | `func iWasExposed(onset:authentication:isFakeRequest:callback:)`
+federationGateway | Specifies whether keys should be exchanged with other compatible countries. Possible values are 'yes', 'no', 'unspecified' (default) | `var federationGateway`
 reset | Removes all SDK related data | `func reset()`
 
 

Sources/DP3TSDK/DP3TSDK.swift

@@ -66,9 +66,11 @@ class DP3TSDK {
     ///   - applicationDescriptor: information about the backend to use
     ///   - urlSession: the url session to use for networking (app can set it to enable certificate pinning)
     ///   - backgroundHandler: handler which gets called on background execution
+    ///   - federationGateway: specifies whether keys should be shared with other countries
     convenience init(applicationDescriptor: ApplicationDescriptor,
                      urlSession: URLSession,
-                     backgroundHandler: DP3TBackgroundHandler?) {
+                     backgroundHandler: DP3TBackgroundHandler?,
+                     federationGateway: FederationGateway) {
         // reset keychain on first launch
         let defaults = Default.shared
         if defaults.isFirstLaunch {
@@ -78,26 +80,28 @@ class DP3TSDK {
             defaults.reset()
         }
 
+        defaults.federationGateway = federationGateway
+
         let exposureDayStorage = ExposureDayStorage()
 
         let manager = ENManager()
         let tracer = ExposureNotificationTracer(manager: manager)
         let matcher = ExposureNotificationMatcher(manager: manager, exposureDayStorage: exposureDayStorage)
         let diagnosisKeysProvider: DiagnosisKeysProvider = manager
 
-        let service = ExposeeServiceClient(descriptor: applicationDescriptor, urlSession: urlSession)
+        let serviceClient = ExposeeServiceClient(descriptor: applicationDescriptor, urlSession: urlSession, federationGateway: federationGateway)
 
-        let synchronizer = KnownCasesSynchronizer(matcher: matcher, service: service, descriptor: applicationDescriptor)
+        let synchronizer = KnownCasesSynchronizer(matcher: matcher, service: serviceClient, descriptor: applicationDescriptor)
 
-        let backgroundTaskManager = DP3TBackgroundTaskManager(handler: backgroundHandler, keyProvider: manager, serviceClient: service, tracer: tracer, manager: manager)
+        let backgroundTaskManager = DP3TBackgroundTaskManager(handler: backgroundHandler, keyProvider: manager, serviceClient: serviceClient, tracer: tracer, manager: manager)
 
         self.init(applicationDescriptor: applicationDescriptor,
                   urlSession: urlSession,
                   tracer: tracer,
                   matcher: matcher,
                   diagnosisKeysProvider: diagnosisKeysProvider,
                   exposureDayStorage: exposureDayStorage,
-                  service: service,
+                  service: serviceClient,
                   synchronizer: synchronizer,
                   backgroundTaskManager: backgroundTaskManager,
                   defaults: defaults)
@@ -222,6 +226,16 @@ class DP3TSDK {
         return state
     }
 
+    var federationGateway: FederationGateway {
+        get {
+            return defaults.federationGateway
+        }
+        set {
+            defaults.federationGateway = newValue
+            service.federationGateway = newValue
+        }
+    }
+
     /// tell the SDK that the user was exposed
     /// This will stop tracing
     /// - Parameters:
@@ -275,7 +289,18 @@ class DP3TSDK {
 
                 mutableKeys.append(contentsOf: self.diagnosisKeysProvider.getFakeKeys(count: fakeKeyCount, startingFrom: startingFrom))
 
+                let withFederationGateway: Bool?
+                switch self.federationGateway {
+                case .yes:
+                    withFederationGateway = true
+                case .no:
+                    withFederationGateway = false
+                case .unspecified:
+                    withFederationGateway = nil
+                }
+
                 let model = ExposeeListModel(gaenKeys: mutableKeys,
+                                             withFederationGateway: withFederationGateway,
                                              fake: isFakeRequest)
 
                 self.service.addExposeeList(model, authentication: authentication) { [weak self] result in

Sources/DP3TSDK/DP3TTracing.swift

@@ -64,15 +64,18 @@ public enum DP3TTracing {
     ///   - enviroment: enviroment to use
     ///   - urlSession: the url session to use for networking (can used to enable certificate pinning)
     ///   - backgroundHandler: a delegate to perform background tasks
+    ///   - federationGateway: specifies whether keys should be shared with other countries
     @available(iOS 12.5, *)
     public static func initialize(with applicationDescriptor: ApplicationDescriptor,
                                   urlSession: URLSession = .shared,
-                                  backgroundHandler: DP3TBackgroundHandler? = nil) {
+                                  backgroundHandler: DP3TBackgroundHandler? = nil,
+                                  federationGateway: FederationGateway = .unspecified) {
         precondition(Self.isOSCompatible, "Operating System is not compatible")
         precondition(instance == nil, "DP3TSDK already initialized")
         instance = DP3TSDK(applicationDescriptor: applicationDescriptor,
                                urlSession: urlSession,
-                               backgroundHandler: backgroundHandler)
+                               backgroundHandler: backgroundHandler,
+                               federationGateway: federationGateway)
     }
 
     @available(iOS 12.5, *)

Sources/DP3TSDK/Models/ExposeeListModel.swift

@@ -23,17 +23,21 @@ struct ExposeeListModel: Encodable {
     /// Diagnosis keys
     let gaenKeys: [CodableDiagnosisKey]
 
+    let withFederationGateway: Bool?
+
     let fake: Bool
 
     func encode(to encoder: Encoder) throws {
         var container = encoder.container(keyedBy: CodingKeys.self)
         // Encode key
         try container.encode(gaenKeys, forKey: .gaenKeys)
-
+        if let withFederationGateway = withFederationGateway {
+            try container.encode(withFederationGateway ? 1 : 0, forKey: .withFederationGateway)
+        }
         try container.encode(fake ? 1 : 0, forKey: .fake)
     }
 
     enum CodingKeys: CodingKey {
-        case gaenKeys, fake
+        case gaenKeys, withFederationGateway, fake
     }
 }

Sources/DP3TSDK/Networking/Endpoints.swift

@@ -33,15 +33,29 @@ struct ExposeeEndpoint {
     /// Get the URL for the exposed people endpoint for a given lastKeyBundleTag
     /// - Parameters:
     ///  - lastKeyBundleTag: last published key tag if one is stored
-    func getExposee(lastKeyBundleTag: String?) -> URL {
+    func getExposee(lastKeyBundleTag: String?, federationGateway: FederationGateway) -> URL {
         let url = baseURLVersionned.appendingPathComponent("gaen")
             .appendingPathComponent("exposed")
 
         var urlComponents = URLComponents(url: url, resolvingAgainstBaseURL: false)
+
+        var queryItems: [URLQueryItem] = []
+
         if let lastKeyBundleTag = lastKeyBundleTag {
-            urlComponents?.queryItems = [
-                URLQueryItem(name: "lastKeyBundleTag", value: lastKeyBundleTag)
-            ]
+            queryItems.append(URLQueryItem(name: "lastKeyBundleTag", value: lastKeyBundleTag))
+        }
+
+        switch federationGateway {
+        case .yes:
+            queryItems.append(URLQueryItem(name: "withFederationGateway", value: "true"))
+        case .no:
+            queryItems.append(URLQueryItem(name: "withFederationGateway", value: "false"))
+        case .unspecified:
+            break
+        }
+
+        if !queryItems.isEmpty {
+            urlComponents?.queryItems = queryItems
         }
 
         guard let finalUrl = urlComponents?.url else {

Sources/DP3TSDK/Networking/ExposeeServiceClient.swift

@@ -23,6 +23,8 @@ protocol ExposeeServiceClientProtocol: class {
 
     var descriptor: ApplicationDescriptor { get }
 
+    var federationGateway: FederationGateway { get set }
+
     /// Get all exposee for a known lastKeyBundleTag
     /// - Parameters:
     ///  - since: last published key tag if one is stored
@@ -52,6 +54,8 @@ class ExposeeServiceClient: ExposeeServiceClientProtocol {
 
     private let jwtVerifier: DP3TJWTVerifier?
 
+    var federationGateway: FederationGateway
+
     private let log = Logger(ExposeeServiceClient.self, category: "exposeeServiceClient")
 
     /// The user agent to send with the requests
@@ -66,7 +70,7 @@ class ExposeeServiceClient: ExposeeServiceClientProtocol {
 
     /// Initialize the client with a  descriptor
     /// - Parameter descriptor: The descriptor to use
-    public init(descriptor: ApplicationDescriptor, urlSession: URLSession = .shared, urlCache: URLCache = .shared) {
+    public init(descriptor: ApplicationDescriptor, urlSession: URLSession = .shared, urlCache: URLCache = .shared, federationGateway: FederationGateway = .unspecified) {
         self.descriptor = descriptor
         self.urlSession = urlSession
         self.urlCache = urlCache
@@ -77,6 +81,7 @@ class ExposeeServiceClient: ExposeeServiceClientProtocol {
         } else {
             jwtVerifier = nil
         }
+        self.federationGateway = federationGateway
     }
     func detectTimeshift(response: HTTPURLResponse) -> DP3TNetworkingError? {
         guard let date = response.date else { return nil }
@@ -102,7 +107,7 @@ class ExposeeServiceClient: ExposeeServiceClientProtocol {
     /// - returns: array of objects or nil if they were already cached
     func getExposee(lastKeyBundleTag: String?, completion: @escaping (Result<ExposeeSuccess, DP3TNetworkingError>) -> Void) -> URLSessionDataTask {
         log.log("getExposeeSynchronously for lastPublishedKeyTag %{public}@", lastKeyBundleTag ?? "nil")
-        let url: URL = exposeeEndpoint.getExposee(lastKeyBundleTag: lastKeyBundleTag)
+        let url: URL = exposeeEndpoint.getExposee(lastKeyBundleTag: lastKeyBundleTag, federationGateway: federationGateway)
 
         var request = URLRequest(url: url, cachePolicy: .useProtocolCachePolicy, timeoutInterval: 60.0)
         request.setValue("application/zip", forHTTPHeaderField: "Accept")

Sources/DP3TSDK/Storage/Defaults.swift

@@ -10,6 +10,12 @@
 
 import Foundation
 
+public enum FederationGateway: Int, Codable {
+    case yes
+    case no
+    case unspecified
+}
+
 protocol DefaultStorage {
     /// stores if this is the first launch of the SDK
     var isFirstLaunch: Bool { get set }
@@ -27,6 +33,8 @@ protocol DefaultStorage {
 
     var exposureDetectionDates: [Date] { get set }
 
+    var federationGateway: FederationGateway { get set }
+
     func reset()
 }
 
@@ -53,6 +61,9 @@ class Default: DefaultStorage {
     @Persisted(userDefaultsKey: "org.dpppt.exposureDetectionDates", defaultValue: [])
     var exposureDetectionDates: [Date]
 
+    @Persisted(userDefaultsKey: "org.dpppt.federationGateway", defaultValue: .unspecified)
+    var federationGateway: FederationGateway
+
     /// Parameters
     private func saveParameters(_ parameters: DP3TParameters) {
 

Tests/DP3TSDKTests/Mocks/MockDefaults.swift

@@ -24,6 +24,8 @@ class MockDefaults: DefaultStorage {
 
     var didMarkAsInfected: Bool = false
 
+    var federationGateway: FederationGateway = .unspecified
+
     func reset() {
         exposureDetectionDates = []
         lastKeyBundleTag = nil

Tests/DP3TSDKTests/Mocks/MockService.swift

@@ -13,13 +13,14 @@ import Foundation
 
 class MockService: ExposeeServiceClientProtocol {
 
-
     static var descriptor: ApplicationDescriptor = .init(appId: "org.dpppt", bucketBaseUrl: URL(string: "https://bucket.dpppt.org")!, reportBaseUrl: URL(string: "https://report.bucket.dpppt.org")!)
 
     var descriptor: ApplicationDescriptor {
         Self.descriptor
     }
 
+    var federationGateway: FederationGateway = .unspecified
+
     var requests: [String?] = []
     let session = MockSession(data: "Data".data(using: .utf8), urlResponse: nil, error: nil)
     let queue = DispatchQueue(label: "synchronous")