feat: Logging decoding errors

Author: plajdo

Sources/GoodNetworking/Extensions/DecodingErrorFormatter.swift

@@ -0,0 +1,47 @@
+//
+//  DecodingErrorFormatter.swift
+//  GoodNetworking
+//
+//  Created by Filip Šašala on 29/09/2025.
+//
+
+import Foundation
+
+internal extension DecodingError {
+
+    var prettyPrinted: String {
+        switch self {
+        case .typeMismatch(_, let context),
+             .valueNotFound(_, let context),
+             .keyNotFound(_, let context),
+             .dataCorrupted(let context):
+            """
+            ⛔️ Decoding failed - \(context.debugDescription)
+               Coding path: \(context.codingPath.prettyPrinted)
+            """
+
+        @unknown default:
+            "⛔️ Decoding failed - unknown error"
+        }
+    }
+
+}
+
+private extension Array where Element == CodingKey {
+
+    var prettyPrinted: String {
+        map { $0.prettyPrinted }.joined(separator: " → ")
+    }
+
+}
+
+private extension CodingKey {
+
+    var prettyPrinted: String {
+        if let intValue = intValue {
+            return "[\(intValue)]"
+        }
+        return stringValue
+    }
+
+}

Sources/GoodNetworking/Session/NetworkSession.swift

@@ -227,6 +227,12 @@ extension NetworkSession {
             let model = try decoder.decode(T.self, from: data)
             return model
         } catch let error as DecodingError {
+            logger.logNetworkEvent(
+                message: error.prettyPrinted,
+                level: .error,
+                file: #file,
+                line: #line
+            )
             throw error.asNetworkError()
         } catch {
             throw URLError(.cannotDecodeRawData).asNetworkError()