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fabianfettfabianfett
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Added AWSLambdaEvents library
1 parent 2cd6bce commit db7f9e6

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‎Package.swift

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@@ -6,6 +6,7 @@ let package = Package(
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name: "swift-aws-lambda-runtime",
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products: [
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.library(name: "AWSLambdaRuntime", targets: ["AWSLambdaRuntime"]),
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.library(name: "AWSLambdaEvents", targets: ["AWSLambdaEvents"]),
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],
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dependencies: [
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.package(url: "https://github.com/apple/swift-nio.git", from: "2.8.0"),
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.product(name: "NIOFoundationCompat", package: "swift-nio"),
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]),
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.testTarget(name: "AWSLambdaRuntimeTests", dependencies: ["AWSLambdaRuntime"]),
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.target(name: "AWSLambdaEvents", dependencies: [
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.product(name: "NIOHTTP1", package: "swift-nio"),
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.product(name: "NIOFoundationCompat", package: "swift-nio"),
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]),
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.testTarget(name: "AWSLambdaEventsTests", dependencies: ["AWSLambdaEvents"]),
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// samples
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.target(name: "StringSample", dependencies: ["AWSLambdaRuntime"]),
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.target(name: "CodableSample", dependencies: ["AWSLambdaRuntime"]),

‎Sources/AWSLambdaEvents/ALB.swift

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//===----------------------------------------------------------------------===//
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//
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// This source file is part of the SwiftAWSLambdaRuntime open source project
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//
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// Copyright (c) 2017-2020 Apple Inc. and the SwiftAWSLambdaRuntime project authors
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// Licensed under Apache License v2.0
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//
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// See LICENSE.txt for license information
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// See CONTRIBUTORS.txt for the list of SwiftAWSLambdaRuntime project authors
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//
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// SPDX-License-Identifier: Apache-2.0
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//
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//===----------------------------------------------------------------------===//
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import class Foundation.JSONEncoder
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import NIO
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import NIOFoundationCompat
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import NIOHTTP1
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// https://github.com/aws/aws-lambda-go/blob/master/events/alb.go
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public enum ALB {
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/// ALBTargetGroupRequest contains data originating from the ALB Lambda target group integration
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public struct TargetGroupRequest: DecodableBody {
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/// ALBTargetGroupRequestContext contains the information to identify the load balancer invoking the lambda
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public struct Context: Codable {
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public let elb: ELBContext
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}
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public let httpMethod: HTTPMethod
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public let path: String
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public let queryStringParameters: [String: [String]]
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public let headers: HTTPHeaders
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public let requestContext: Context
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public let isBase64Encoded: Bool
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public let body: String?
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}
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/// ELBContext contains the information to identify the ARN invoking the lambda
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public struct ELBContext: Codable {
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public let targetGroupArn: String
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}
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public struct TargetGroupResponse {
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public let statusCode: HTTPResponseStatus
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public let statusDescription: String?
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public let headers: HTTPHeaders?
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public let body: String
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public let isBase64Encoded: Bool
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public init(
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statusCode: HTTPResponseStatus,
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statusDescription: String? = nil,
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headers: HTTPHeaders? = nil,
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body: String = "",
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isBase64Encoded: Bool = false
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) {
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self.statusCode = statusCode
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self.statusDescription = statusDescription
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self.headers = headers
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self.body = body
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self.isBase64Encoded = isBase64Encoded
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}
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}
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}
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// MARK: - Request -
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extension ALB.TargetGroupRequest: Decodable {
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enum CodingKeys: String, CodingKey {
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case httpMethod
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case path
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case queryStringParameters
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case multiValueQueryStringParameters
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case headers
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case multiValueHeaders
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case requestContext
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case isBase64Encoded
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case body
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}
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public init(from decoder: Decoder) throws {
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let container = try decoder.container(keyedBy: CodingKeys.self)
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let method = try container.decode(String.self, forKey: .httpMethod)
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self.httpMethod = HTTPMethod(rawValue: method)
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self.path = try container.decode(String.self, forKey: .path)
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// crazy multiple headers
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// https://docs.aws.amazon.com/elasticloadbalancing/latest/application/lambda-functions.html#multi-value-headers
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if let multiValueQueryStringParameters =
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try container.decodeIfPresent([String: [String]].self, forKey: .multiValueQueryStringParameters) {
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self.queryStringParameters = multiValueQueryStringParameters
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} else {
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let singleValueQueryStringParameters = try container.decode(
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[String: String].self,
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forKey: .queryStringParameters
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)
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self.queryStringParameters = singleValueQueryStringParameters.mapValues { [$0] }
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}
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if let multiValueHeaders =
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try container.decodeIfPresent([String: [String]].self, forKey: .multiValueHeaders) {
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self.headers = HTTPHeaders(awsHeaders: multiValueHeaders)
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} else {
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let singleValueHeaders = try container.decode(
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[String: String].self,
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forKey: .headers
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)
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let multiValueHeaders = singleValueHeaders.mapValues { [$0] }
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self.headers = HTTPHeaders(awsHeaders: multiValueHeaders)
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}
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self.requestContext = try container.decode(Context.self, forKey: .requestContext)
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self.isBase64Encoded = try container.decode(Bool.self, forKey: .isBase64Encoded)
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let body = try container.decode(String.self, forKey: .body)
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self.body = body != "" ? body : nil
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}
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}
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// MARK: - Response -
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extension ALB.TargetGroupResponse: Encodable {
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static let MultiValueHeadersEnabledKey =
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CodingUserInfoKey(rawValue: "ALB.TargetGroupResponse.MultiValueHeadersEnabledKey")!
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enum CodingKeys: String, CodingKey {
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case statusCode
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case statusDescription
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case headers
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case multiValueHeaders
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case body
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case isBase64Encoded
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}
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public func encode(to encoder: Encoder) throws {
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var container = encoder.container(keyedBy: CodingKeys.self)
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try container.encode(statusCode.code, forKey: .statusCode)
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let multiValueHeaderSupport =
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encoder.userInfo[ALB.TargetGroupResponse.MultiValueHeadersEnabledKey] as? Bool ?? false
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switch (multiValueHeaderSupport, headers) {
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case (true, .none):
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try container.encode([String: String](), forKey: .multiValueHeaders)
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case (false, .none):
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try container.encode([String: [String]](), forKey: .headers)
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case (true, .some(let headers)):
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var multiValueHeaders: [String: [String]] = [:]
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headers.forEach { name, value in
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var values = multiValueHeaders[name] ?? []
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values.append(value)
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multiValueHeaders[name] = values
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}
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try container.encode(multiValueHeaders, forKey: .multiValueHeaders)
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case (false, .some(let headers)):
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var singleValueHeaders: [String: String] = [:]
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headers.forEach { name, value in
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singleValueHeaders[name] = value
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}
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try container.encode(singleValueHeaders, forKey: .headers)
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}
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try container.encodeIfPresent(statusDescription, forKey: .statusDescription)
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try container.encodeIfPresent(body, forKey: .body)
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try container.encodeIfPresent(isBase64Encoded, forKey: .isBase64Encoded)
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}
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}
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extension ALB.TargetGroupResponse {
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public init<Payload: Encodable>(
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statusCode: HTTPResponseStatus,
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statusDescription: String? = nil,
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headers: HTTPHeaders? = nil,
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payload: Payload,
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encoder: JSONEncoder = JSONEncoder()
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) throws {
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var headers = headers ?? HTTPHeaders()
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headers.add(name: "Content-Type", value: "application/json")
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self.statusCode = statusCode
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self.statusDescription = statusDescription
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self.headers = headers
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var buffer = try encoder.encodeAsByteBuffer(payload, allocator: ByteBufferAllocator())
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guard let string = buffer.readString(length: buffer.readableBytes) else {
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fatalError("buffer.readString(length: buffer.readableBytes) failed")
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}
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self.body = string
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self.isBase64Encoded = false
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}
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/// Use this method to send any arbitrary byte buffer back to the API Gateway.
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/// Sadly Apple currently doesn't seem to be confident enough to advertise
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/// their base64 implementation publically. SAD. SO SAD. Therefore no
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/// ByteBuffer for you my friend.
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public init(
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statusCode: HTTPResponseStatus,
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statusDescription: String? = nil,
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headers: HTTPHeaders? = nil,
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buffer: NIO.ByteBuffer
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) {
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let headers = headers ?? HTTPHeaders()
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self.statusCode = statusCode
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self.statusDescription = statusDescription
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self.headers = headers
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self.body = buffer.withUnsafeReadableBytes { (ptr) -> String in
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String(base64Encoding: ptr)
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}
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self.isBase64Encoded = true
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}
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}

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