add more sense to readme, fix 400 error because of id

README.md

@@ -40,7 +40,36 @@ Import the framework in your project:
 
 [Create an OpenAI API key](https://platform.openai.com/account/api-keys) and add it to your configuration:
 
-`let openAI = OpenAISwift(authToken: "TOKEN")`
+`let openAI: OpenAISwift = OpenAISwift(config: OpenAISwift.Config.makeDefaultOpenAI(apiKey: "TOKEN"))`
+
+
+To follow [OpenAI requirements](https://platform.openai.com/docs/api-reference/authentication) 
+
+>  Remember that your API key is a secret! Do not share it with others or expose it in any client-side code (browsers, apps). Production requests must be routed through your own backend server where your API key can be securely loaded from an environment variable or key management service.
+
+and basic industrial safety you should not call OpenAI API directly. 
+
+```swift
+private lazy var proxyOpenAIBackend: OpenAISwift = .init(
+        config: OpenAISwift.Config(
+            baseURL: "http://localhost",
+            endpointPrivider: OpenAIEndpointProvider(source: .proxy(path: { _ -> String in
+                "/chat/completions"
+            }, method: { _ -> String in
+                "POST"
+            })),
+            session: session,
+            authorizeRequest: { [weak self] request in
+                self?.authorizeRequest(&request)
+            }
+        ))
+
+    private func authorizeRequest(_ request: inout URLRequest) {
+        if let apiKey = try? Encryptor.getApiToken() {
+            request.setValue(apiKey, forHTTPHeaderField: "X-API-KEY")
+        }
+    }
+```
 
 This framework supports Swift concurrency; each example below has both an async/await and completion handler variant.
 

Sources/OpenAISwift/Models/ChatMessage.swift

@@ -34,6 +34,18 @@ public struct ChatMessage: Codable, Identifiable {
         self.role = role
         self.content = content
     }
+
+
+    // MARK: - Custom Encoding
+    public func encode(to encoder: Encoder) throws {
+        var container = encoder.container(keyedBy: CodingKeys.self)
+        try container.encodeIfPresent(role, forKey: .role)
+        try container.encodeIfPresent(content, forKey: .content)
+    }
+
+    private enum CodingKeys: String, CodingKey {
+        case role, content
+    }
 }
 
 /// A structure that represents a chat conversation.

Sources/OpenAISwift/OpenAISwift.swift

@@ -5,6 +5,7 @@ import FoundationXML
 #endif
 
 public enum OpenAIError: Error {
+    case networkError(code: Int)
     case genericError(error: Error)
     case decodingError(error: Error)
     case chatError(error: ChatError.Payload)
@@ -294,11 +295,15 @@ extension OpenAISwift {
         let task = session.dataTask(with: request) { (data, response, error) in
             if let error = error {
                 completionHandler(.failure(error))
+            } else if let response = response as? HTTPURLResponse, !(200...299).contains(response.statusCode) {
+                completionHandler(.failure(OpenAIError.networkError(code: response.statusCode)))
             } else if let data = data {
                 completionHandler(.success(data))
+            } else {
+                let error = NSError(domain: "OpenAI", code: 6666, userInfo: [NSLocalizedDescriptionKey: "Unknown error"])
+                completionHandler(.failure(OpenAIError.genericError(error: error)))
             }
         }
-
         task.resume()
     }