feat: poc: Telemetry architecture

ConfidenceDemoApp/ConfidenceDemoApp/ConfidenceDemoApp.swift

@@ -20,7 +20,7 @@ struct ConfidenceDemoApp: App {
         WindowGroup {
             let secret = ProcessInfo.processInfo.environment["CLIENT_SECRET"] ?? ""
             let confidence = Confidence.Builder(clientSecret: secret, loggerLevel: .TRACE)
-                .withContext(initialContext: ["targeting_key": ConfidenceValue(string: UUID.init().uuidString)])
+//                .withContext(initialContext: ["targeting_key": ConfidenceValue(string: UUID.init().uuidString)])
                 .build()
 
             let status = Status()
@@ -42,6 +42,6 @@ struct ConfidenceDemoApp: App {
 
 extension ConfidenceDemoApp {
     func setup(confidence: Confidence) async throws {
-        try await confidence.fetchAndActivate()
+//        try await confidence.fetchAndActivate()
     }
 }

ConfidenceDemoApp/ConfidenceDemoApp/ContentView.swift

@@ -6,6 +6,10 @@ struct ContentView: View {
     @ObservedObject var status: Status
     @StateObject var text = DisplayText()
     @StateObject var color = FlagColor()
+    @State private var user = "logged out"
+    @State private var logginIn = false
+    @State private var evaluationReason = "Last Reason: ---"
+    @State private var evaluationError = "Last Error: ---"
 
     private let confidence: Confidence
 
@@ -17,24 +21,88 @@ struct ContentView: View {
     var body: some View {
         if case .ready = status.state {
             VStack {
+                Text("Current user:")
+                if (logginIn) {
+                    ProgressView()
+                } else {
+                    Text("\(user)")
+                        .font(.title)
+                        .bold()
+                }
+                Spacer()
                 Image(systemName: "flag")
                     .imageScale(.large)
+                    .font(.title)
                     .foregroundColor(color.color)
                     .padding(10)
                 Text(text.text)
+                Spacer()
+                Button("Login yellow user") {
+                    confidence.putContext(key: "user_id", value: ConfidenceValue.init(string: "user1"))
+                    Task {
+                        logginIn = true
+                        try await confidence.fetchAndActivate()
+                        user = "yellow_user"
+                        logginIn = false
+                    }
+                }
+                Button("Login green user") {
+                    confidence.putContext(key: "user_id", value: ConfidenceValue.init(string: "user2"))
+                    Task {
+                        logginIn = true
+                        try await confidence.fetchAndActivate()
+                        logginIn = false
+                        user = "green_user"
+                    }
+                }
+                .padding(.bottom)
                 Button("Get remote flag value") {
-                    text.text = confidence.getValue(key: "swift-demoapp.color", defaultValue: "ERROR")
+                    let eval = confidence.getEvaluation(key: "swift-demoapp.color", defaultValue: "DefaultValue")
+                    evaluationReason = "Last Reason: \(eval.reason)"
+                    evaluationError = "Last Error: \(eval.errorCode?.description ?? .none ?? "None")"
+                    text.text = eval.value
                     if text.text == "Green" {
                         color.color = .green
                     } else if text.text == "Yellow" {
                         color.color = .yellow
                     } else {
-                        color.color = .red
+                        color.color = .gray
                     }
                 }
+                VStack(alignment: .leading) {
+                    HStack {
+                        Text(evaluationReason)
+                            .padding(.horizontal)
+                        Spacer()
+                    }
+                    HStack {
+                        Text(evaluationError)
+                            .padding(.horizontal)
+                        Spacer()
+                    }
+                }
+                .padding(.bottom)
+                Button("Get remote flag value with TypeMismatch ⚠️") {
+                    let eval = confidence.getEvaluation(key: "swift-demoapp.color", defaultValue: true)
+                    evaluationReason = "Last Reason: \(eval.reason)"
+                    evaluationError = "Last Error: \(eval.errorCode?.description ?? .none ?? "None")"
+                    if text.text == "Green" {
+                        color.color = .green
+                    } else if text.text == "Yellow" {
+                        color.color = .yellow
+                    } else {
+                        color.color = .gray
+                    }
+                }
+                .padding(.bottom)
+                Button("Generate event") {
+                    try! confidence.track(eventName: "Test", data: [:])
+                }
+                .padding(.top)
                 Button("Flush 🚽") {
                     confidence.flush()
                 }
+                .padding(.bottom)
             }
             .padding()
         } else if case .error(let error) = status.state {
@@ -51,6 +119,10 @@ struct ContentView: View {
     }
 }
 
+class Model: ObservableObject {
+
+}
+
 class DisplayText: ObservableObject {
     @Published var text = "Hello World!"
 }

Package.resolved

@@ -1,6 +1,15 @@
 {
   "object": {
     "pins": [
+      {
+        "package": "SwiftProtobuf",
+        "repositoryURL": "https://github.com/apple/swift-protobuf.git",
+        "state": {
+          "branch": null,
+          "revision": "ebc7251dd5b37f627c93698e4374084d98409633",
+          "version": "1.28.2"
+        }
+      },
       {
         "package": "OpenFeature",
         "repositoryURL": "[email protected]:open-feature/swift-sdk.git",

Package.swift

@@ -19,11 +19,14 @@ let package = Package(
     ],
     dependencies: [
         .package(url: "[email protected]:open-feature/swift-sdk.git", from: "0.1.0"),
+        .package(url: "https://github.com/apple/swift-protobuf.git", from: "1.0.0"),
     ],
     targets: [
         .target(
             name: "Confidence",
-            dependencies: [],
+            dependencies: [
+                .product(name: "SwiftProtobuf", package: "swift-protobuf")
+            ],
             plugins: []
         ),
         .target(

Sources/Confidence/Apply/FlagApplierWithRetries.swift

@@ -11,6 +11,7 @@ final class FlagApplierWithRetries: FlagApplier {
     private let cacheDataInteractor: CacheDataActor
     private let metadata: ConfidenceMetadata
     private let debugLogger: DebugLogger?
+    private let telemetry = Telemetry.shared
 
     init(
         httpClient: HttpClient,
@@ -139,7 +140,8 @@ final class FlagApplierWithRetries: FlagApplier {
         request: ApplyFlagsRequest
     ) async -> ApplyFlagResult {
         do {
-            return try await httpClient.post(path: ":apply", data: request)
+            let header: Data = telemetry.getSnapshot()
+            return try await httpClient.post(path: ":apply", data: request, header: header)
         } catch {
             return .failure(handleError(error: error))
         }

Sources/Confidence/Confidence.swift

@@ -23,8 +23,6 @@ public class Confidence: ConfidenceEventSender {
     internal let remoteFlagResolver: ConfidenceResolveClient
     internal let contextReconciliatedChanges = PassthroughSubject<String, Never>()
 
-    public static let sdkId: String = "SDK_ID_SWIFT_CONFIDENCE"
-
     required init(
         clientSecret: String,
         region: ConfidenceRegion,
@@ -398,9 +396,7 @@ extension Confidence {
                 credentials: ConfidenceClientCredentials.clientSecret(secret: clientSecret),
                 region: region,
                 timeoutIntervalForRequest: timeout)
-            let metadata = ConfidenceMetadata(
-                name: sdkId,
-                version: "1.0.1") // x-release-please-version
+            let metadata = ConfidenceMetadata.defaultMetadata
             let uploader = RemoteConfidenceClient(
                 options: options,
                 metadata: metadata,

Sources/Confidence/ConfidenceMetadata.swift

@@ -1,11 +1,15 @@
 import Foundation
 
 struct ConfidenceMetadata {
+    private static let sdkName: String = "SDK_ID_SWIFT_CONFIDENCE"
+    private static let sdkId: Int = 13 // TODO enstablish cross-language identifiers
+
+    public var id: Int
     public var name: String
     public var version: String
 
-    public init(name: String, version: String) {
-        self.name = name
-        self.version = version
-    }
+    public static let defaultMetadata = ConfidenceMetadata(
+        id: sdkId,
+        name: sdkName,
+        version: "1.0.1") // x-release-please-version
 }

Sources/Confidence/FlagEvaluation.swift

@@ -8,12 +8,27 @@ public struct Evaluation<T> {
     public let errorMessage: String?
 }
 
-public enum ErrorCode {
+public enum ErrorCode: CustomStringConvertible {
     case providerNotReady
     case invalidContext
     case flagNotFound
     case evaluationError
     case typeMismatch
+
+    public var description: String {
+        switch self {
+        case .providerNotReady:
+            return "Provider is not ready."
+        case .invalidContext:
+            return "Invalid context."
+        case .flagNotFound:
+            return "Flag not found."
+        case .evaluationError:
+            return "Evaluation error occurred."
+        case .typeMismatch:
+            return "Type mismatch encountered."
+        }
+    }
 }
 
 struct FlagResolution: Encodable, Decodable, Equatable {
@@ -75,6 +90,7 @@ extension FlagResolution {
                 var resolveReason: ResolveReason = .match
                 if self.context != context {
                     resolveReason = .stale
+                    Telemetry.shared.incrementStaleAccess()
                 }
                 if let typedValue = typedValue {
                     return Evaluation(
@@ -95,6 +111,7 @@ extension FlagResolution {
                             errorMessage: nil
                         )
                     } else {
+                        Telemetry.shared.incrementFlagTypeMismatch()
                         return Evaluation(
                             value: defaultValue,
                             variant: nil,

Sources/Confidence/Http/HttpClient.swift

@@ -4,6 +4,7 @@ typealias HttpClientResult<T> = Result<HttpClientResponse<T>, Error>
 
 internal protocol HttpClient {
     func post<T: Decodable>(path: String, data: Encodable) async throws -> HttpClientResult<T>
+    func post<T: Decodable>(path: String, data: Encodable, header: Data) async throws -> HttpClientResult<T>
 }
 
 struct HttpClientResponse<T> {

Sources/Confidence/Http/NetworkClient.swift

@@ -29,11 +29,22 @@
         self.timeoutIntervalForRequests = timeoutIntervalForRequests
     }
 
+    func post<T>(path: String, data: any Encodable, header: Data) async throws -> HttpClientResult<T> where T : Decodable {
+        let request = try buildRequest(path: path, data: data, header: header)
+        return try await post(request: request)
+    }
+
     public func post<T: Decodable>(
         path: String,
         data: Encodable
     ) async throws -> HttpClientResult<T> {
         let request = try buildRequest(path: path, data: data)
+        return try await post(request: request)
+    }
+
+    private func post<T: Decodable>(
+        request: URLRequest
+    ) async throws -> HttpClientResult<T>  {
         let requestResult = await perform(request: request, retry: self.retry)
         if let error = requestResult.error {
             return .failure(error)
@@ -96,7 +107,7 @@
         return URL(string: "\(normalisedBase)\(normalisedPath)")
     }
 
-    private func buildRequest(path: String, data: Encodable) throws -> URLRequest {
+    private func buildRequest(path: String, data: Encodable, header: Data? = nil) throws -> URLRequest {
         guard let url = constructURL(base: baseUrl, path: path) else {
             throw ConfidenceError.internalError(message: "Could not create service url")
         }
@@ -107,9 +118,17 @@
         request.addValue("application/json", forHTTPHeaderField: "Content-Type")
         request.addValue("application/json", forHTTPHeaderField: "Accept")
 
+
         let encoder = JSONEncoder()
         encoder.dateEncodingStrategy = .iso8601
 
+        if let header = header {
+            request.addValue(header.base64EncodedString(), forHTTPHeaderField: "Confidence-Metadata")
+            // TMP - TESTING
+            let telemetryData = try LibraryData(serializedBytes: header)
+            print(telemetryData)
+        }
+
         let jsonData = try encoder.encode(data)
         request.httpBody = jsonData
 

Sources/Confidence/RemoteConfidenceClient.swift

@@ -7,6 +7,7 @@ public class RemoteConfidenceClient: ConfidenceClient {
     private var httpClient: HttpClient
     private var baseUrl: String
     private let debugLogger: DebugLogger?
+    private let telemetry = Telemetry.shared
 
     init(
         options: ConfidenceClientOptions,
@@ -44,9 +45,10 @@ public class RemoteConfidenceClient: ConfidenceClient {
             sendTime: timeString,
             sdk: Sdk(id: metadata.name, version: metadata.version)
         )
+        let header = telemetry.getSnapshot()
         do {
             let result: HttpClientResult<PublishEventResponse> =
-            try await self.httpClient.post(path: ":publish", data: request)
+            try await self.httpClient.post(path: ":publish", data: request, header: header)
             switch result {
             case .success(let successData):
                 let status = successData.response.statusCode

Sources/Confidence/RemoteResolveConfidenceClient.swift

@@ -4,6 +4,7 @@ class RemoteConfidenceResolveClient: ConfidenceResolveClient {
     private let targetingKey = "targeting_key"
     private var options: ConfidenceClientOptions
     private let metadata: ConfidenceMetadata
+    private let telemetry = Telemetry.shared
 
     private var httpClient: HttpClient
     private var applyOnResolve: Bool
@@ -33,10 +34,10 @@ class RemoteConfidenceResolveClient: ConfidenceResolveClient {
             apply: applyOnResolve,
             sdk: Sdk(id: metadata.name, version: metadata.version)
         )
-
+        let header = telemetry.getSnapshot()
         do {
             let result: HttpClientResult<ResolveFlagsResponse> =
-            try await self.httpClient.post(path: ":resolve", data: request)
+            try await self.httpClient.post(path: ":resolve", data: request, header: header)
             switch result {
             case .success(let successData):
                 guard successData.response.status == .ok else {