Implement #684

Source/SocketIO/Engine/SocketEngine.swift

@@ -44,6 +44,9 @@ public final class SocketEngine : NSObject, URLSessionDelegate, SocketEnginePoll
         }
     }
 
+    /// A dictionary of extra http headers that will be set during connection.
+    public var extraHeaders: [String: String]?
+
     /// A queue of engine.io messages waiting for POSTing
     ///
     /// **You should not touch this directly**
@@ -73,9 +76,6 @@ public final class SocketEngine : NSObject, URLSessionDelegate, SocketEnginePoll
     /// An array of HTTPCookies that are sent during the connection.
     public private(set) var cookies: [HTTPCookie]?
 
-    /// A dictionary of extra http headers that will be set during connection.
-    public private(set) var extraHeaders: [String: String]?
-
     /// When `true`, the engine is in the process of switching to WebSockets.
     ///
     /// **Do not touch this directly**

Source/SocketIO/Engine/SocketEngineSpec.swift

@@ -52,7 +52,7 @@ import Starscream
     var engineQueue: DispatchQueue { get }
 
     /// A dictionary of extra http headers that will be set during connection.
-    var extraHeaders: [String: String]? { get }
+    var extraHeaders: [String: String]? { get set }
 
     /// When `true`, the engine is in the process of switching to WebSockets.
     var fastUpgrade: Bool { get }

Tests/TestSocketIO/SocketEngineTest.swift

@@ -192,6 +192,14 @@ class SocketEngineTest: XCTestCase {
         XCTAssertTrue(manager.engine!.forceWebsockets)
     }
 
+    func testChangingEngineHeadersAfterInit() {
+        engine.extraHeaders = ["Hello": "World"]
+
+        let req = engine.createRequestForPostWithPostWait()
+
+        XCTAssertEqual("World", req.allHTTPHeaderFields?["Hello"])
+    }
+
     var manager: SocketManager!
     var socket: SocketIOClient!
     var engine: SocketEngine!

Tests/TestSocketIO/SocketSideEffectTest.swift

@@ -450,7 +450,7 @@ class TestEngine : SocketEngineSpec {
     var connectParams: [String: Any]? = nil
     private(set) var cookies: [HTTPCookie]? = nil
     private(set) var engineQueue = DispatchQueue.main
-    private(set) var extraHeaders: [String: String]? = nil
+    var extraHeaders: [String: String]? = nil
     private(set) var fastUpgrade = false
     private(set) var forcePolling = false
     private(set) var forceWebsockets = false