extension URL : ExpressibleByStringLiteral

Author: kaunteya

MacCacheCleaner/AppDelegate.swift

@@ -7,12 +7,12 @@
 //
 
 import Cocoa
-let sourceJSONPath = "https://raw.githubusercontent.com/kaunteya/MacCacheCleaner/master/Source.json"
+let sourceJSONPath: URL = "https://raw.githubusercontent.com/kaunteya/MacCacheCleaner/master/Source.json"
 
 @NSApplicationMain
 class AppDelegate: NSObject, NSApplicationDelegate {
 
-    let cacheListFetcher = CacheFetcher(urlString: sourceJSONPath)
+    let cacheListFetcher = CacheFetcher.init(url: sourceJSONPath)
 
     let cacheList = CacheList()
 

MacCacheCleaner/Extensions/URLSession+Result.swift

@@ -14,12 +14,13 @@ enum Result<Value> {
 }
 
 extension URLSession {
-    func dataTask<T: Decodable>(
-        with request: URLRequest,
+
+    func jsonDecodableTask<T: Decodable>(
+        with url: URL,
         completion: @escaping (Result<T>) -> Void
         ) -> URLSessionDataTask {
 
-        return self.dataTask(with: request) { (data, response, error) in
+        return self.dataTask(with: url) { (data, response, error) in
             guard error == nil else {
                 completion(.failure(error!))
                 return
@@ -29,8 +30,33 @@ extension URLSession {
                 return
             }
 
-            let decoded = try! JSONDecoder().decode(T.self, from: data)
-            completion(.success(decoded))
+            if let decoded = try? JSONDecoder().decode(T.self, from: data) {
+                completion(.success(decoded))
+            } else {
+                completion(.failure(nil))
+            }
+        }
+    }
+
+    func jsonSerializedTask<T>(
+        with request: URL,
+        completion: @escaping (Result<T>) -> Void
+        ) -> URLSessionDataTask {
+
+        return self.dataTask(with: request) { (data, response, error) in
+            guard error == nil else {
+                completion(.failure(error!))
+                return
+            }
+            guard let data = data, let _ = response else {
+                completion(.failure(nil))
+                return
+            }
+            if let json = try! JSONSerialization.jsonObject(with: data, options: []) as? T {
+                completion(.success(json))
+            } else {
+                completion(.failure(nil))
+            }
         }
     }
 }

MacCacheCleaner/Models/CacheFetcher.swift

@@ -14,12 +14,12 @@ struct SourceJSON: Decodable {
 }
 
 struct CacheFetcher {
-    let urlString: String
+    let url: URL
 
     func fromNetwork(completion: @escaping([CacheItem]) -> Void,
                  failure: ((Error?) -> Void)?) {
-        let urlRequest = URLRequest(url: URL(string: urlString)!)
-        URLSession.shared.dataTask(with: urlRequest) { (result:Result<SourceJSON>)  in
+
+        URLSession.shared.jsonDecodableTask(with: url) { (result:Result<SourceJSON>)  in
             switch result {
             case .success(let decoded):
                 assert(decoded.version == 1)

MacCacheCleaner/Others/Other.swift

@@ -8,3 +8,10 @@
 
 import AppKit
 
+extension URL : ExpressibleByStringLiteral {
+    public typealias StringLiteralType = String
+
+    public init(stringLiteral value: StringLiteralType) {
+        self.init(string: value)!
+    }
+}