feat: persistent storage, httpclient, eventpipeline

.swiftlint.yml

@@ -8,3 +8,10 @@ identifier_name:
   allowed_symbols: "_"
   min_length: 1
 cyclomatic_complexity: 25
+nesting:
+  type_level:
+    warning: 3
+    error: 6
+  function_level:
+    warning: 5
+    error: 10

Examples/Apps/IOSExample/README.md

@@ -0,0 +1,4 @@
+## iOS Example
+TODO: This is the location to put iOS Example.
+
+However, got some problem when creating a new Swift Project here. Tried to convert the SDK Package to Project then delete the folder reference to only track file changes by git. Got some other problems when converting the Package to Project. Leave a comment here to revisit.

Sources/Amplitude/Amplitude.swift

@@ -11,7 +11,7 @@ public class Amplitude {
     lazy var timeline: Timeline = {
         return Timeline()
     }()
-    lazy var logger: any Logger = {
+    lazy var logger: (any Logger)? = {
         return self.configuration.loggerProvider
     }()
 
@@ -108,7 +108,7 @@ public class Amplitude {
         return self
     }
 
-    func onEnterForeground(timestamp: Double) {
+    func onEnterForeground(timestamp: Int64) {
         inForeground = true
 
         let dummySessionStartEvent = BaseEvent(eventType: "session_start")
@@ -131,10 +131,10 @@ public class Amplitude {
 
     private func process(event: BaseEvent) {
         if configuration.optOut {
-            logger.log(message: "Skip event based on opt out configuration")
+            logger?.log(message: "Skip event based on opt out configuration")
             return
         }
-        event.timestamp = event.timestamp ?? NSDate().timeIntervalSince1970
+        event.timestamp = event.timestamp ?? Int64(NSDate().timeIntervalSince1970 * 1000)
         timeline.process(event: event)
     }
 }

Sources/Amplitude/Configuration.swift

@@ -38,7 +38,7 @@ public class Configuration {
         flushIntervalMillis: Int = Constants.Configuration.FLUSH_INTERVAL_MILLIS,
         instanceName: String = Constants.Configuration.DEFAULT_INSTANCE,
         optOut: Bool = false,
-        storageProvider: any Storage = PersistentStorage(),
+        storageProvider: (any Storage)? = nil,
         logLevel: LogLevelEnum = LogLevelEnum.WARN,
         loggerProvider: any Logger = ConsoleLogger(),
         minIdLength: Int? = nil,
@@ -63,7 +63,7 @@ public class Configuration {
         self.flushIntervalMillis = flushIntervalMillis
         self.instanceName = instanceName
         self.optOut = optOut
-        self.storageProvider = storageProvider
+        self.storageProvider = storageProvider ?? PersistentStorage(apiKey: apiKey)
         self.logLevel = logLevel
         self.loggerProvider = loggerProvider
         self.minIdLength = minIdLength

Sources/Amplitude/Events/BaseEvent.swift

@@ -59,9 +59,9 @@ public class BaseEvent: EventOptions, Codable {
     init(
         userId: String? = nil,
         deviceId: String? = nil,
-        timestamp: Double? = nil,
-        eventId: Double? = nil,
-        sessionId: Double? = -1,
+        timestamp: Int64? = nil,
+        eventId: Int64? = nil,
+        sessionId: Int64? = -1,
         insertId: String? = nil,
         locationLat: Double? = nil,
         locationLng: Double? = nil,
@@ -200,9 +200,9 @@ public class BaseEvent: EventOptions, Codable {
         super.init()
         userId = try values.decode(String.self, forKey: .userId)
         deviceId = try values.decode(String.self, forKey: .deviceId)
-        timestamp = try values.decode(Double.self, forKey: .timestamp)
-        eventId = try values.decode(Double.self, forKey: .eventId)
-        sessionId = try values.decode(Double.self, forKey: .sessionId)
+        timestamp = try values.decode(Int64.self, forKey: .timestamp)
+        eventId = try values.decode(Int64.self, forKey: .eventId)
+        sessionId = try values.decode(Int64.self, forKey: .sessionId)
         locationLat = try values.decode(Double.self, forKey: .locationLat)
         locationLng = try values.decode(Double.self, forKey: .locationLng)
         appVersion = try values.decode(String.self, forKey: .appVersion)

Sources/Amplitude/Events/EventOptions.swift

@@ -10,9 +10,9 @@ import Foundation
 public class EventOptions {
     var userId: String?
     var deviceId: String?
-    var timestamp: Double?
-    var eventId: Double?
-    var sessionId: Double? = -1
+    var timestamp: Int64?
+    var eventId: Int64?
+    var sessionId: Int64? = -1
     var insertId: String?
     var locationLat: Double?
     var locationLng: Double?
@@ -45,14 +45,14 @@ public class EventOptions {
     var extra: [String: Any]?
     var callback: EventCallBack?
     var partnerId: String?
-    private var attempts: Int
+    internal var attempts: Int
 
     init(
         userId: String? = nil,
         deviceId: String? = nil,
-        timestamp: Double? = nil,
-        eventId: Double? = nil,
-        sessionId: Double? = -1,
+        timestamp: Int64? = nil,
+        eventId: Int64? = nil,
+        sessionId: Int64? = -1,
         insertId: String? = nil,
         locationLat: Double? = nil,
         locationLng: Double? = nil,

Sources/Amplitude/Mediator.swift

@@ -23,8 +23,8 @@ internal class Mediator {
         var result: BaseEvent? = event
         plugins.forEach { plugin in
             if let r = result {
-                if plugin is DestinationPlugin {
-                    _ = plugin.execute(event: r)
+                if let p = plugin as? DestinationPlugin {
+                    _ = p.process(event: r)
                 } else if let p = plugin as? EventPlugin {
                     result = p.execute(event: r)
                     if let rr = result {

Sources/Amplitude/Plugins/AmplitudeDestinationPlugin.swift

@@ -19,7 +19,6 @@ public class AmplitudeDestinationPlugin: DestinationPlugin {
                 logger?.error(message: "Event is invalid for missing information like userId and deviceId")
             }
         }
-
     }
 
     public func track(event: BaseEvent) -> BaseEvent? {

Sources/Amplitude/Plugins/ContextPlugin.swift

@@ -76,7 +76,7 @@ class ContextPlugin: Plugin {
 
     internal func mergeContext(event: BaseEvent, context: [String: Any]) {
         if event.timestamp == nil {
-            event.timestamp = NSDate().timeIntervalSince1970 * 1000
+            event.timestamp = Int64(NSDate().timeIntervalSince1970 * 1000)
         }
         if event.insertId == nil {
             event.insertId = NSUUID().uuidString

Sources/Amplitude/Plugins/Mac/MacOSLifecycleMonitor.swift

@@ -82,7 +82,7 @@
 
     extension AmplitudeDestinationPlugin: MacOSLifecycle {
         public func applicationDidBecomeActive() {
-            let timestamp = NSDate().timeIntervalSince1970
+            let timestamp = Int64(NSDate().timeIntervalSince1970 * 1000)
             self.amplitude?.onEnterForeground(timestamp: timestamp)
         }
 

Sources/Amplitude/Plugins/iOS/IOSLifecycleMonitor.swift

@@ -94,7 +94,7 @@
 
     extension AmplitudeDestinationPlugin: IOSLifecycle {
         public func applicationWillEnterForeground(application: UIApplication?) {
-            let timestamp = NSDate().timeIntervalSince1970
+            let timestamp = Int64(NSDate().timeIntervalSince1970 * 1000)
             self.amplitude?.onEnterForeground(timestamp: timestamp)
         }
 

Sources/Amplitude/Plugins/watchOS/WatchOSLifecycleMonitor.swift

@@ -88,7 +88,7 @@
 
     extension AmplitudeDestinationPlugin: WatchOSLifecycle {
         public func applicationWillEnterForeground(watchExtension: WKExtension) {
-            let timestamp = NSDate().timeIntervalSince1970
+            let timestamp = Int64(NSDate().timeIntervalSince1970 * 1000)
             self.amplitude?.onEnterForeground(timestamp: timestamp)
         }
 

Sources/Amplitude/Storages/InMemoryStorage.swift

@@ -19,14 +19,12 @@ class InMemoryStorage: Storage {
     func reset() async {
 
     }
-}
 
-extension InMemoryStorage {
-    enum StorageKey: String, CaseIterable {
-        case LAST_EVENT_ID = "last_event_id"
-        case PREVIOUS_SESSION_ID = "previous_session_id"
-        case LAST_EVENT_TIME = "last_event_time"
-        case OPT_OUT = "opt_out"
-        case EVENTS = "events"
+    func rollover() async {
+
+    }
+
+    func getEventsString(eventBlock: Any) async -> String? {
+        return nil
     }
 }

Sources/Amplitude/Storages/PersistentStorage.swift

@@ -1,5 +1,5 @@
 //
-//  File.swift
+//  PersistentStorage.swift
 //
 //
 //  Created by Marvin Liu on 10/28/22.
@@ -47,6 +47,17 @@ actor PersistentStorage: Storage {
         return result
     }
 
+    func getEventsString(eventBlock: Any) async -> String? {
+        var content: String?
+        guard let eventBlock = eventBlock as? URL else { return content }
+        do {
+            content = try String(contentsOf: eventBlock, encoding: .utf8)
+        } catch {
+            amplitude?.logger?.error(message: error.localizedDescription)
+        }
+        return content
+    }
+
     func reset() async {
         let urls = getEventFiles(includeUnfinished: true)
         let keys = userDefaults?.dictionaryRepresentation().keys
@@ -58,6 +69,19 @@ actor PersistentStorage: Storage {
         }
     }
 
+    func rollover() async {
+        let currentFile = getCurrentFile()
+        if fileManager?.fileExists(atPath: currentFile.path) == false {
+            return
+        }
+        if let attributes = try? fileManager?.attributesOfItem(atPath: currentFile.path),
+            let fileSize = attributes[FileAttributeKey.size] as? UInt64,
+            fileSize >= 0
+        {
+            finish(file: currentFile)
+        }
+    }
+
     func isBasicType(value: Any?) -> Bool {
         var result = false
         if value == nil {
@@ -80,14 +104,6 @@ extension PersistentStorage {
     static let MAX_FILE_SIZE = 975000  // 975KB
     static let TEMP_FILE_EXTENSION = "tmp"
 
-    enum StorageKey: String, CaseIterable {
-        case LAST_EVENT_ID = "last_event_id"
-        case PREVIOUS_SESSION_ID = "previous_session_id"
-        case LAST_EVENT_TIME = "last_event_time"
-        case OPT_OUT = "opt_out"
-        case EVENTS = "events"
-    }
-
     enum Exception: Error {
         case unsupportedType
     }
@@ -186,15 +202,15 @@ extension PersistentStorage {
         let jsonString = event.toString()
         do {
             if outputStream == nil {
-                amplitude?.logger.error(message: "OutputStream is nil with file: \(storeFile)")
+                amplitude?.logger?.error(message: "OutputStream is nil with file: \(storeFile)")
             }
             if newFile == false {
                 // prepare for the next entry
                 try outputStream?.write(",")
             }
             try outputStream?.write(jsonString)
         } catch {
-            amplitude?.logger.error(message: error.localizedDescription)
+            amplitude?.logger?.error(message: error.localizedDescription)
         }
     }
 
@@ -205,7 +221,7 @@ extension PersistentStorage {
             try outputStream?.create()
             try outputStream?.write(contents)
         } catch {
-            amplitude?.logger.error(message: error.localizedDescription)
+            amplitude?.logger?.error(message: error.localizedDescription)
         }
     }
 
@@ -215,15 +231,15 @@ extension PersistentStorage {
             do {
                 outputStream = try OutputFileStream(fileURL: file)
             } catch {
-                amplitude?.logger.error(message: error.localizedDescription)
+                amplitude?.logger?.error(message: error.localizedDescription)
             }
         }
 
         if let outputStream = outputStream {
             do {
                 try outputStream.open()
             } catch {
-                amplitude?.logger.error(message: error.localizedDescription)
+                amplitude?.logger?.error(message: error.localizedDescription)
             }
         }
     }
@@ -237,7 +253,7 @@ extension PersistentStorage {
         do {
             try outputStream.write(fileEnding)
         } catch {
-            amplitude?.logger.error(message: error.localizedDescription)
+            amplitude?.logger?.error(message: error.localizedDescription)
         }
         outputStream.close()
         self.outputStream = nil
@@ -246,7 +262,7 @@ extension PersistentStorage {
         do {
             try fileManager?.moveItem(at: file, to: fileWithoutTemp)
         } catch {
-            amplitude?.logger.error(message: "Unable to rename file: \(file.path)")
+            amplitude?.logger?.error(message: "Unable to rename file: \(file.path)")
         }
 
         let currentFileIndex: Int = (userDefaults?.integer(forKey: eventsFileKey) ?? 0) + 1

Sources/Amplitude/Timeline.swift

@@ -21,7 +21,6 @@ public class Timeline {
         let beforeResult = applyPlugin(pluginType: PluginType.before, event: event)
         let enrichmentResult = applyPlugin(pluginType: PluginType.enrichment, event: beforeResult)
         _ = applyPlugin(pluginType: PluginType.destination, event: enrichmentResult)
-
     }
 
     internal func applyPlugin(pluginType: PluginType, event: BaseEvent?) -> BaseEvent? {
@@ -30,7 +29,6 @@ public class Timeline {
             result = mediator.execute(event: event!)
         }
         return result
-
     }
 
     internal func add(plugin: Plugin) {

Sources/Amplitude/Types.swift

@@ -22,12 +22,21 @@ public protocol EventCallBack {
 }
 
 public protocol Storage {
-    associatedtype StorageKey: RawRepresentable where StorageKey.RawValue: StringProtocol
     func write(key: StorageKey, value: Any?) async throws
     func read<T>(key: StorageKey) async -> T?
+    func getEventsString(eventBlock: Any) async -> String?
+    func rollover() async
     func reset() async
 }
 
+public enum StorageKey: String, CaseIterable {
+    case LAST_EVENT_ID = "last_event_id"
+    case PREVIOUS_SESSION_ID = "previous_session_id"
+    case LAST_EVENT_TIME = "last_event_time"
+    case OPT_OUT = "opt_out"
+    case EVENTS = "events"
+}
+
 public protocol Logger {
     associatedtype LogLevel: RawRepresentable
     var logLevel: Int? { get set }

Sources/Amplitude/Utilities/Atomic.swift

@@ -0,0 +1,35 @@
+//
+//  Atomic.swift
+//
+//
+//  Created by Marvin Liu on 11/29/22.
+//
+
+import Foundation
+
+@propertyWrapper
+public struct Atomic<T> {
+    var value: T
+    private let lock = NSLock()
+
+    public init(wrappedValue value: T) {
+        self.value = value
+    }
+
+    public var wrappedValue: T {
+        get { return load() }
+        set { store(newValue: newValue) }
+    }
+
+    func load() -> T {
+        lock.lock()
+        defer { lock.unlock() }
+        return value
+    }
+
+    mutating func store(newValue: T) {
+        lock.lock()
+        defer { lock.unlock() }
+        value = newValue
+    }
+}