API client - initial commit

.gitignore

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+TestCredentials.swift

ChangellyAPI.podspec

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+#
+# Be sure to run `pod lib lint ChangellyAPI.podspec' to ensure this is a
+# valid spec before submitting.
+#
+# Any lines starting with a # are optional, but their use is encouraged
+# To learn more about a Podspec see https://guides.cocoapods.org/syntax/podspec.html
+#
+
+Pod::Spec.new do |s|
+  s.name             = 'ChangellyAPI'
+  s.version          = '0.1.0'
+  s.summary          = 'A short description of ChangellyAPI.'
+
+# This description is used to generate tags and improve search results.
+#   * Think: What does it do? Why did you write it? What is the focus?
+#   * Try to keep it short, snappy and to the point.
+#   * Write the description between the DESC delimiters below.
+#   * Finally, don't worry about the indent, CocoaPods strips it!
+
+  s.description      = <<-DESC
+TODO: Add long description of the pod here.
+                       DESC
+
+  s.homepage         = 'https://github.com/coinpaprika/changelly-api-swift-client'
+  s.license          = { :type => 'MIT', :file => 'LICENSE' }
+  s.author           = { 'Dominique Stranz' => '[email protected]' }
+  s.source           = { :git => 'https://github.com/coinpaprika/changelly-api-swift-client.git', :tag => s.version.to_s }
+  s.source           = { :git => 'https://github.com/Dominique Stranz/ChangellyAPI.git', :tag => s.version.to_s }
+  s.social_media_url = 'https://twitter.com/coinpaprika'
+
+  s.ios.deployment_target = '10.0'
+
+  s.source_files = 'ChangellyAPI/Classes/**/*'
+
+  # s.resource_bundles = {
+  #   'ChangellyAPI' => ['ChangellyAPI/Assets/*.png']
+  # }
+
+  # s.public_header_files = 'Pod/Classes/**/*.h'
+  # s.frameworks = 'UIKit', 'MapKit'
+  s.dependency 'CoinpaprikaAPI/Networking'
+end

ChangellyAPI/Classes/ChangellyAPI.swift

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+//
+//  ChangellyAPI.swift
+//  ChangellyAPI
+//
+//  Created by Dominique Stranz on 10/04/2019.
+//
+
+import Foundation
+
+public struct ChangellyAPI {
+    private let credentials: Credentials
+    private let baseUrl: URL = URL(string: "https://api.changelly.com")!
+
+    public init(key: String, secret: String) {
+        self.credentials = Credentials(key: key, secret: secret)
+    }
+
+    public func getCurrencies() -> JsonRpcRequest<[String]> {
+        return JsonRpcRequest<[String]>(baseUrl: baseUrl, method: "getCurrencies", params: [:], credentials: credentials)
+    }
+
+    public func getCurrenciesFull() -> JsonRpcRequest<[Currency]> {
+        return JsonRpcRequest<[Currency]>(baseUrl: baseUrl, method: "getCurrenciesFull", params: [:], credentials: credentials)
+    }
+
+    public func getMinAmount(from: String, to: String) -> JsonRpcRequest<Decimal> {
+        return JsonRpcRequest<Decimal>(baseUrl: baseUrl, method: "getMinAmount", params: ["from": from, "to": to], credentials: credentials)
+    }
+
+    public func getExchangeAmount(from: String, to: String, amount: Decimal) -> JsonRpcRequest<String> {
+        return JsonRpcRequest<String>(baseUrl: baseUrl, method: "getExchangeAmount", params: ["from": from, "to": to, "amount": amount], credentials: credentials)
+    }
+
+    public func createTransaction(from: String, to: String, amount: Decimal, address: String, extraId: String? = nil, refundAddress: String? = nil, refundExtraId: String? = nil) -> JsonRpcRequest<Transaction> {
+        var params: [String : Any] = ["from": from, "to": to, "amount": amount, "address": address]
+        params["extraId"] = extraId
+        params["refundAddress"] = refundAddress
+        params["refundExtraId"] = refundExtraId
+        return JsonRpcRequest<Transaction>(baseUrl: baseUrl, method: "createTransaction", params: params, credentials: credentials)
+    }
+
+    public func getTransactions(currency: String? = nil, address: String? = nil, extraId: String? = nil, limit: Int? = nil, offset: Int? = nil) -> JsonRpcRequest<[TransactionLog]> {
+        var params = [String : Any]()
+        params["currency"] = currency
+        params["address"] = address
+        params["extraId"] = extraId
+        params["limit"] = limit
+        params["offset"] = offset
+        return JsonRpcRequest<[TransactionLog]>(baseUrl: baseUrl, method: "getTransactions", params: params, credentials: credentials)
+    }
+
+    public func getStatus(id: String) -> JsonRpcRequest<Transaction.Status> {
+        return JsonRpcRequest<Transaction.Status>(baseUrl: baseUrl, method: "getStatus", params: ["id": id], credentials: credentials)
+    }
+
+
+
+}

ChangellyAPI/Classes/Models/Currency.swift

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+//
+//  Currency.swift
+//  ChangellyAPI
+//
+//  Created by Dominique Stranz on 10/04/2019.
+//
+
+import Foundation
+
+public struct Currency: Codable {
+    public let name: String
+    public let fullName: String
+    public let enabled: Bool
+    public let fixRateEnabled: Bool
+    public let payinConfirmations: Int
+    public let extraIdName: String?
+    public let addressUrl: String?
+    public let transactionUrl: String?
+    public let image: URL
+    public let fixedTime: Int
+}

ChangellyAPI/Classes/Models/Transaction.swift

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+//
+//  Transaction.swift
+//  ChangellyAPI
+//
+//  Created by Dominique Stranz on 10/04/2019.
+//
+
+import Foundation
+import CoinpaprikaAPI
+
+public struct Transaction: Codable, CodableModel {
+    public let id: String
+    public let apiExtraFee: String
+    public let changellyFee: String
+    public let payinExtraId: String?
+    public let payoutExtraId: String?
+    public let amountExpectedFrom: Decimal
+    public let amountExpectedTo: String
+    public let status: Status
+    public let currencyFrom: String
+    public let currencyTo: String
+    public let payinAddress: String
+    public let payoutAddress: String
+    public let createdAt: Date
+    public let kycRequired: Bool
+
+    public enum Status: String, Codable {
+        case new
+        case waiting
+        case confirming
+        case exchanging
+        case sending
+        case finished
+        case failed
+        case refunded
+        case overdue
+        case hold
+
+        var localizedDescription: String {
+            switch self {
+            case .new:
+                return "Freshly created transaction."
+            case .waiting:
+                return "Transaction is waiting for an incoming payment."
+            case .confirming:
+                return "We have received payin and are waiting for certain amount of confirmations depending of incoming currency."
+            case .exchanging:
+                return "Payment was confirmed and is being exchanged."
+            case .sending:
+                return "Coins are being sent to the recipient address."
+            case .finished:
+                return "Coins were successfully sent to the recipient address."
+            case .failed:
+                return "Transaction has failed. In most cases, the amount was less than the minimum. Please contact support and provide a transaction id."
+            case .refunded:
+                return "Exchange failed and coins were refunded to user's wallet. The wallet address should be provided by user."
+            case .overdue:
+                return "We did not receive any payment since 36 hours from transaction creation."
+            case .hold:
+                return "Due to AML/KYC procedure, exchange may be delayed"
+            }
+        }
+
+        static var dateFormatter: DateFormatter {
+            let formatter = DateFormatter()
+            formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"
+            return formatter
+        }
+
+        static var dateDecodingStrategy: JSONDecoder.DateDecodingStrategy? {
+            return .formatted(dateFormatter)
+        }
+    }
+}

ChangellyAPI/Classes/Models/TransactionLog.swift

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+//
+//  TransactionLog.swift
+//  ChangellyAPI
+//
+//  Created by Dominique Stranz on 10/04/2019.
+//
+
+import Foundation
+import CoinpaprikaAPI
+
+public struct TransactionLog: Codable, CodableModel {
+    public let id: String
+    public let createdAt: Date
+    public let moneyReceived: Decimal
+    public let moneySent: Decimal
+    public let payinConfirmations: String
+    public let status: Transaction.Status
+    public let currencyFrom: String
+    public let currencyTo: String
+    public let payinAddress: String
+    public let payinExtraId: String?
+    public let payinHash: String?
+    public let amountExpectedFrom: String
+    public let payoutAddress: String
+    public let payoutExtraId: String?
+    public let payoutHash: String?
+    public let refundHash: String?
+    public let amountFrom: String
+    public let amountTo: String
+    public let networkFee: String?
+    public let changellyFee: String
+    public let apiExtraFee: String
+
+    static var dateDecodingStrategy: JSONDecoder.DateDecodingStrategy? {
+        return .secondsSince1970
+    }
+}

ChangellyAPI/Classes/Request/Credentials.swift

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+//
+//  Credentials.swift
+//  ChangellyAPI
+//
+//  Created by Dominique Stranz on 10/04/2019.
+//
+
+import Foundation
+
+public struct Credentials {
+    public let key: String
+    public let secret: String
+
+    internal func signature(for data: Data) -> String? {
+        guard let jsonString = String(data: data, encoding: .utf8) else {
+            return nil
+        }
+
+        return jsonString.hmac(key: secret)
+    }
+}

ChangellyAPI/Classes/Request/JsonRpcRequest.swift

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+//
+//  Request+JSON-RPC.swift
+//  Coinpaprika
+//
+//  Created by Dominique Stranz on 06.09.2018.
+//  Copyright © 2018 Grey Wizard sp. z o.o. All rights reserved.
+//
+
+import Foundation
+import CoinpaprikaAPI
+
+public struct JsonRpcRequest<Model: Codable> {
+
+    let request: Request<JsonRpcResponseEvelope<Model>>
+
+    init(baseUrl: URL, method: String, params: [String: Any], credentials: Credentials) {
+        let requestId = JsonRpcIdentifier.next()
+        let rpcBody = ["jsonrpc": "2.0", "method": method, "id": requestId, "params": params] as [String: Any]
+        request = Request<JsonRpcResponseEvelope<Model>>(baseUrl: baseUrl, method: .post, path: "", params: rpcBody, userAgent: "Changelly API Client - Swift", authorisation: .dynamic(signer: { (request) in
+            guard let jsonData = request.httpBody, let signature = credentials.signature(for: jsonData) else {
+                return
+            }
+
+            request.addValue(credentials.key, forHTTPHeaderField: "api-key")
+            request.addValue(signature, forHTTPHeaderField: "sign")
+        }))
+    }
+
+    public func perform(responseQueue: DispatchQueue? = nil, cachePolicy: URLRequest.CachePolicy? = nil, _ callback: @escaping (Result<Model, Error>) -> Void) {
+        request.perform(responseQueue: responseQueue, cachePolicy: cachePolicy) { (response) in
+            switch response {
+            case .success(let envelope):
+                if let result = envelope.result {
+                    callback(Result.success(result))
+                } else if let error = envelope.error {
+                    callback(Result.failure(JsonRpcError.serviceError(code: error.code, message: error.message)))
+                } else {
+                    callback(Result.failure(JsonRpcError.unableToDecodeEnvelope))
+                }
+            case .failure(let error):
+                callback(Result.failure(error))
+            }
+        }
+    }
+}
+
+struct JsonRpcIdentifier {
+    private static var currentId: Int = 1
+
+    static func next() -> Int {
+        defer { currentId += 1 }
+        return currentId
+    }
+}
+
+enum JsonRpcError: Error {
+    case unableToDecodeEnvelope
+    case serviceError(code: Int, message: String)
+}
+
+extension JsonRpcError: LocalizedError {
+    public var errorDescription: String? {
+        switch self {
+        case .unableToDecodeEnvelope:
+            return "Unable to decode response"
+        case .serviceError(_, let message):
+            return "\(message)"
+        }
+    }
+}
+
+struct JsonRpcResponseEvelope<Model: Codable>: Codable, CodableModel {
+    let id: Int
+    let result: Model?
+    let error: JsonRpcErrorEnvelope?
+
+    static var dateDecodingStrategy: JSONDecoder.DateDecodingStrategy? {
+        if codableModel = model as? CodableModel {
+            return Model.dateDecodingStrategy
+        }
+
+        return nil
+    }
+}
+
+struct JsonRpcErrorEnvelope: Codable {
+    let code: Int
+    let message: String
+}

ChangellyAPI/Classes/Request/String+HMAC.swift

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+//
+//  String+HMAC.swift
+//  ChangellyAPI
+//
+//  Created by Dominique Stranz on 10/04/2019.
+//
+
+import Foundation
+import CommonCrypto
+
+extension String {
+    func hmac(key: String) -> String {
+        var digest = [UInt8](repeating: 0, count: Int(CC_SHA512_DIGEST_LENGTH))
+        CCHmac(CCHmacAlgorithm(kCCHmacAlgSHA512), key, key.count, self, self.count, &digest)
+        let data = Data(bytes: digest)
+        return data.map { String(format: "%02hhx", $0) }.joined()
+    }
+}