NetNewsWire/Shared/HTMLMetadata/HTMLMetadataDownloader.swift

44 lines
1.2 KiB
Swift

//
// HTMLMetadataDownloader.swift
// NetNewsWire
//
// Created by Brent Simmons on 11/26/17.
// Copyright © 2017 Ranchero Software. All rights reserved.
//
import Foundation
import RSWeb
import RSParser
struct HTMLMetadataDownloader {
static let serialDispatchQueue = DispatchQueue(label: "HTMLMetadataDownloader")
static func downloadMetadata(for url: String, _ completion: @escaping (RSHTMLMetadata?) -> Void) {
guard let actualURL = URL(unicodeString: url) else {
completion(nil)
return
}
downloadUsingCache(actualURL) { (data, response, error) in
if let data = data, !data.isEmpty, let response = response, response.statusIsOK, error == nil {
let urlToUse = response.url ?? actualURL
let parserData = ParserData(url: urlToUse.absoluteString, data: data)
parseMetadata(with: parserData, completion)
return
}
completion(nil)
}
}
private static func parseMetadata(with parserData: ParserData, _ completion: @escaping (RSHTMLMetadata?) -> Void) {
serialDispatchQueue.async {
let htmlMetadata = RSHTMLMetadataParser.htmlMetadata(with: parserData)
DispatchQueue.main.async {
completion(htmlMetadata)
}
}
}
}