change fetch function from network layer to one with an escaping closure #3
Conversation
test FeedDataManager test models gotten from network call can be mapped to cell view models
| enum TweetAPIError: Error { | ||
| case noData | ||
| case response | ||
| case parsingData | ||
| } | ||
|
|
||
| class FeedDataManager: FeedDataManagerProtocol { |
There was a problem hiding this comment.
Any class that does not implement inheritance should be defined as final class.
There was a problem hiding this comment.
It is a good practice to define all classes as final when there is no inheritance. This help to the compiler's performance.
| } | ||
|
|
||
|
|
||
| let decoder = JSONDecoder() |
There was a problem hiding this comment.
I think is better to pass the JSONDecoder instance as a parameter instead of creating it inside this method. If you do that, you are applying dependency injection because the JSONDecoder is a dependency for your method.
| let url = URL(string: "https://gist.githubusercontent.com/ferdelarosa-wz/0c73ab5311c845fb7dfac4b62ab6c652/raw/6a39cffe68d87f1613f222372c62bd4e89ad06fa/tweets.json") | ||
| guard let url else { return } | ||
|
|
||
| let request = URLRequest(url: url) |
There was a problem hiding this comment.
the request should be a parameter for the fetch method. I understand that it is just one url for this project but I just trying to do this in a general way.
| } | ||
|
|
||
| do { | ||
| let jsonData = try decoder.decode(TweetsResponse.self, from: data) |
There was a problem hiding this comment.
It only works for the TweetsResponse. Here you can define a generic method to do the data decoding. Just like this:
func decode<T: Decodable>(data: Data?, decoder: JSONDecoder = JSONDecoder()) -> T? {
return try? decoder.decode(T.self, from: data ?? Data())
}
| import XCTest | ||
| @testable import MiniBootcamp | ||
|
|
||
| class FeedDataManagerTests: XCTestCase { |
There was a problem hiding this comment.
Also, it's good to define final the classes for the test cases.
test FeedDataManager
test models gotten from network call can be mapped to cell view models