support older macos

Author: t089

Diff for: Package.swift

@@ -6,7 +6,6 @@ let swiftSettings: [SwiftSetting] = [.enableExperimentalFeature("StrictConcurren
 
 let package = Package(
     name: "swift-aws-lambda-events",
-    platforms: [.macOS(.v12)],
     products: [
         .library(name: "AWSLambdaEvents", targets: ["AWSLambdaEvents"])
     ],

Diff for: Sources/AWSLambdaEvents/Utils/DateWrappers.swift

@@ -18,6 +18,8 @@ import FoundationEssentials
 import Foundation
 #endif
 
+
+
 @propertyWrapper
 public struct ISO8601Coding: Decodable, Sendable {
     public let wrappedValue: Date
@@ -30,8 +32,16 @@ public struct ISO8601Coding: Decodable, Sendable {
         let container = try decoder.singleValueContainer()
         let dateString = try container.decode(String.self)
 
+        struct InvalidDateError: Error {}
+
         do {
-            self.wrappedValue = try Date(dateString, strategy: .iso8601)
+            if #available(macOS 12.0, *) {
+                self.wrappedValue = try Date(dateString, strategy: .iso8601)
+            } else if let date = Self.dateFormatter.date(from: dateString) {
+                self.wrappedValue = date
+            } else {
+                throw InvalidDateError()
+            }
         } catch {
             throw DecodingError.dataCorruptedError(
                 in: container,
@@ -40,6 +50,14 @@ public struct ISO8601Coding: Decodable, Sendable {
             )
         }
     }
+
+    private static var dateFormatter: DateFormatter {
+        let formatter = DateFormatter()
+        formatter.locale = Locale(identifier: "en_US_POSIX")
+        formatter.timeZone = TimeZone(secondsFromGMT: 0)
+        formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZZZZZ"
+        return formatter
+    }
 }
 
 @propertyWrapper
@@ -53,8 +71,17 @@ public struct ISO8601WithFractionalSecondsCoding: Decodable, Sendable {
     public init(from decoder: Decoder) throws {
         let container = try decoder.singleValueContainer()
         let dateString = try container.decode(String.self)
+
+        struct InvalidDateError: Error {}
+
         do {
-            self.wrappedValue = try Date(dateString, strategy: Self.iso8601WithFractionalSeconds)
+            if #available(macOS 12.0, *) {
+                self.wrappedValue = try Date(dateString, strategy: Self.iso8601WithFractionalSeconds)
+            } else if let date = Self.dateFormatter.date(from: dateString) {
+                self.wrappedValue = date
+            } else {
+                throw InvalidDateError()
+            }
         } catch {
             throw DecodingError.dataCorruptedError(
                 in: container,
@@ -64,6 +91,15 @@ public struct ISO8601WithFractionalSecondsCoding: Decodable, Sendable {
         }
     }
 
+    private static var dateFormatter: DateFormatter {
+        let formatter = DateFormatter()
+        formatter.locale = Locale(identifier: "en_US_POSIX")
+        formatter.timeZone = TimeZone(secondsFromGMT: 0)
+        formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSZZZZZ"
+        return formatter
+    }
+
+    @available(macOS 12.0, *)
     private static var iso8601WithFractionalSeconds: Date.ISO8601FormatStyle {
         Date.ISO8601FormatStyle(includingFractionalSeconds: true)
     }
@@ -82,7 +118,11 @@ public struct RFC5322DateTimeCoding: Decodable, Sendable {
         let string = try container.decode(String.self)
 
         do {
-            self.wrappedValue = try Date(string, strategy: RFC5322DateStrategy())
+            if #available(macOS 12.0, *) {
+                self.wrappedValue = try Date(string, strategy: RFC5322DateStrategy())
+            } else {
+                self.wrappedValue = try RFC5322DateStrategy().parse(string)
+            }
         } catch {
             throw DecodingError.dataCorruptedError(
             in: container,
@@ -95,7 +135,7 @@ public struct RFC5322DateTimeCoding: Decodable, Sendable {
 
 struct RFC5322DateParsingError: Error {}
 
-struct RFC5322DateStrategy: ParseStrategy {
+struct RFC5322DateStrategy {
     func parse(_ input: String) throws -> Date {
         guard let components = self.components(from: input) else {
             throw RFC5322DateParsingError()
@@ -219,11 +259,11 @@ struct RFC5322DateStrategy: ParseStrategy {
             guard it.expect(UInt8(ascii: ":")) else { return nil }
             guard let second = parseSecond(&it) else { return nil }
 
-            guard let timezoneOffset = parseTimezone(&it) else { return nil }
+            guard let timezoneOffsetMinutes = parseTimezone(&it) else { return nil }
 
             return DateComponents(
                 calendar: Calendar(identifier: .gregorian),
-                timeZone: TimeZone(secondsFromGMT: timezoneOffset * 60),
+                timeZone: TimeZone(secondsFromGMT: timezoneOffsetMinutes * 60),
                 year: year,
                 month: month,
                 day: day,
@@ -235,6 +275,9 @@ struct RFC5322DateStrategy: ParseStrategy {
     }
 }
 
+@available(macOS 12.0, *)
+extension RFC5322DateStrategy: ParseStrategy { }
+
 extension IteratorProtocol where Self.Element == UInt8 {
     mutating func expect(_ expected: UInt8) -> Bool {
         guard self.next() == expected else { return false }
@@ -305,5 +348,4 @@ let timezoneOffsetMap: [Array<UInt8> : Int] = [
     Array("CDT".utf8): -5 * 60,
     Array("MDT".utf8): -6 * 60,
     Array("PDT".utf8): -7 * 60,
-    
 ]