Implement new messaging API

SignalServiceKit/src/Loki/LokiMessage.swift

@@ -0,0 +1,49 @@
+import PromiseKit
+
+@objc public final class LokiMessage : NSObject {
+    /// The hex encoded public key of the receiver.
+    let destination: String
+    /// The content of the message.
+    let data: LosslessStringConvertible
+    /// The time to live for the message.
+    let ttl: UInt64
+    /// When the proof of work was calculated.
+    let timestamp: UInt64
+    /// The base 64 encoded proof of work.
+    let nonce: String
+    
+    init(destination: String, data: LosslessStringConvertible, ttl: UInt64, timestamp: UInt64, nonce: String) {
+        self.destination = destination
+        self.data = data
+        self.ttl = ttl
+        self.timestamp = timestamp
+        self.nonce = nonce
+    }
+    
+    public static func fromSignalMessage(_ signalMessage: SignalMessage) -> Promise<LokiMessage> {
+        return Promise<LokiMessage> { seal in
+            DispatchQueue.global(qos: .default).async {
+                let destination = signalMessage["destination"]!
+                let data = signalMessage["content"]!
+                let ttl = LokiMessagingAPI.defaultTTL
+                let timestamp = UInt64(Date().timeIntervalSince1970)
+                if let nonce = ProofOfWork.calculate(data: data, pubKey: destination, timestamp: timestamp, ttl: Int(ttl)) {
+                    let result = LokiMessage(destination: destination, data: data, ttl: ttl, timestamp: timestamp, nonce: nonce)
+                    seal.fulfill(result)
+                } else {
+                    seal.reject(LokiMessagingAPI.Error.proofOfWorkCalculationFailed)
+                }
+            }
+        }
+    }
+    
+    func toJSON() -> [String:String] {
+        return [
+            "destination" : destination,
+            "data" : data.description,
+            "ttl" : String(ttl),
+            "timestamp" : String(timestamp),
+            "nonce" : nonce
+        ]
+    }
+}

SignalServiceKit/src/Loki/LokiMessagingAPI.swift

@@ -5,6 +5,7 @@ import PromiseKit
     private static var baseURL: String { return textSecureServerURL }
     private static var port: String { return "8080" }
     private static var apiVersion: String { return "v1" }
+    public static let defaultTTL: UInt64 = 4 * 24 * 60 * 60
     
     // MARK: Types
     private enum Method : String {
@@ -14,18 +15,32 @@ import PromiseKit
     
     public typealias RawResponse = TSNetworkManager.NetworkManagerResult
     
+    public enum Error : LocalizedError {
+        case proofOfWorkCalculationFailed
+        
+        public var errorDescription: String? {
+            switch self {
+            case .proofOfWorkCalculationFailed: return NSLocalizedString("Failed to calculate proof of work.", comment: "")
+            }
+        }
+    }
+    
     // MARK: Lifecycle
     override private init() { }
     
     // MARK: API
-    private static func invoke(_ method: Method, parameters: [String:String] = [:]) -> (request: TSRequest, promise: Promise<RawResponse>) {
+    private static func invoke(_ method: Method, parameters: [String:String] = [:]) -> Promise<RawResponse> {
         let url = URL(string: "\(baseURL):\(port)/\(apiVersion)/storage_rpc")!
         let request = TSRequest(url: url, method: "POST", parameters: [ "method" : method.rawValue, "params" : parameters ])
-        return (request, TSNetworkManager.shared().makePromise(request: request))
+        return TSNetworkManager.shared().makePromise(request: request)
     }
 
-    @objc public static func sendMessage(_ message: [String:String]) -> TSRequest {
-        return invoke(.sendMessage, parameters: message).request
+    public static func sendSignalMessage(_ signalMessage: SignalMessage, to destination: String) -> Promise<RawResponse> {
+        return LokiMessage.fromSignalMessage(signalMessage).then(sendMessage)
+    }
+    
+    public static func sendMessage(_ lokiMessage: LokiMessage) -> Promise<RawResponse> {
+        return invoke(.sendMessage, parameters: lokiMessage.toJSON())
     }
     
     public static func retrieveAllMessages() -> Promise<RawResponse> {
@@ -33,6 +48,6 @@ import PromiseKit
             "pubKey" : OWSIdentityManager.shared().identityKeyPair()!.hexEncodedPublicKey,
             "lastHash" : "" // TODO: Implement
         ]
-        return invoke(.retrieveAllMessages, parameters: parameters).promise
+        return invoke(.retrieveAllMessages, parameters: parameters)
     }
 }

SignalServiceKit/src/Loki/SignalMessage.swift

@@ -0,0 +1,2 @@
+
+public typealias SignalMessage = [String:String]

SignalServiceKit/src/Network/API/Requests/OWSRequestFactory.m

@@ -405,7 +405,7 @@ NS_ASSUME_NONNULL_BEGIN
     NSString *path = [textSecureMessagesAPI stringByAppendingString:recipientId];
     NSDictionary *parameters = [lokiMessages objectAtIndex:0];
 
-    return [LokiMessagingAPI sendMessage:parameters];
+    return [TSRequest new]; // TODO: Just here to make things build
 }
 
 + (TSRequest *)submitMessageRequestWithRecipient:(NSString *)recipientId